Literature overview implantology

Alongside safety in clinical application, a modern implant system provides scientific documentation which covers essential aspects. Users can therefore rely on a product system that has been carefully designed and tried and tested in its practical application. It is safe and efficient.

This literature overview provides a systematic presentation of scientific publications on the tioLogic® and Tiolox® implant systems. A large number of studies prove the long-term success of these products. Different treatment approaches and field reports on these implant systems are presented in brief content summaries of the relevant publication (incl. publication source in specialist journals or the name of the publisher in question).  

Each publication is subject to copyright protection and may only be used, beyond the legally defined limits, with the consent of the respective authors and publishers. Please understand therefore that, for legal reasons, we are not permitted to disclose these publications in full text. Please contact the publisher indicated in case a contribution is not freely accessible in the specialist literature.  

Take a look at the scientific documentation for Tiolox® and all tioLogic® implants – if you have any queries, please contact us.



All Studies Publications

Elsyad M, Hatem O, Shawky A, Emera R

Effect of Different Degres of Mesial Implant Inclination on the Retention and Stability of Two-Implant Mandibular Overdentures Retained with Stud
Attachments: An In Vitro Study

The International Journal of Oral & Maxillofacial Implants 2017

To evaluate the effect of different degrees of mesial implant inclinations on the retention and
stability of two-implant mandibular overdentures retained with stud attachments.

Materials and Methods:
Four experimental mandibular acrylic models were constructed. Two laboratory implants
were inserted in the canine areas of each model with the following degrees of mesial
inclinations: 0, 5, 10, and 20 degrees. Experimental overdentures were connected
to the implants with Locator extra-light retention (Le), Locator light retention (Li), and
Locator medium retention (Lm). Vertical (retention) and oblique (stability) dislodging
forces (anterior, posterior, and lateral) were measured at the beginning of the study
(initial retention) and after 540 cycles of denture insertion and removal (final retention).

The final retention was not signifi cantly affected by small (5 degrees) and large
(20 degrees) implant inclinations, but decreased with a moderate (10 degrees) inclination.
For a small implant inclination (5 degrees), Lm shows the highest fi nal retention/stability
an Le showed the lowest, while for moderate and large inclinations (10 and 20 degrees),
Le showed the highest fi nal retention/stability and Lm showed the lowest. Vertical dislodging
recorded the highest fi nal stability, and lateral dislodgment recorded the lowest

Within the limitations of this in vitro study, only moderate implant angulation (10 degrees)
negatively affects the final retention and stability of Locator-retained overdentures. Locator
medium retention for small angulation (5 degrees) and Locator extra-light retention for
moderate (10 degrees) and large (20 degrees) angulations are recommended to maintain
high retention and stability after 540 cycles of denture insertion and removal.

Elsyad M, Emera R, Ashmawy T

Effect of Distal Implant Inclination on Dislodging Forces of Different Locator Attachments Used for Mandibular Overdentures: An In Vitro Study

Journal of Prosthodontics 00 (2017) 1 – 9

To evaluate the effect of distal implant inclination on axial and nonaxial retentive forces of
different Locator attachments used to retain mandibular overdentures.

Materials and Methods:
Four duplicate mandibular edentulous acrylic models received 2 implants in the canine areas
with 0°, 5°, 10°, and 20° distal inclinations. Experimental overdentures were connected to
the implants with Locator extra light retention (Le), Locator light retention (Ll), and Locator
medium retention (Lm). For the 20° model, extended range Locator extra-light retention (Lee)
and Locator medium retention (Lem) were used. Axial and nonaxial (anterior, posterior, lateral)
retentive forces were measured initially and after 540 cycles of denture insertion and removal.
Three-way mixed ANOVA was used to analyze axial and nonaxial retentive forces.

After wear simulation, 20° angulation showed the highest axial retention for Le and Ll
while 5° showed the highest retention for Lm; 0° and 5° showed the highest anterior and
posterior retention for Lm; 20° showed the highest lateral retention for Le and Ll. For all
implant inclinations, Lm showed the highest axial and nonaxial retention, and Le and Lee
showed the lowest retention for 10° and 20° inclined implants, respectively.

Axial and nonaxial retention of Locator attachments for implantretained overdentures are
signifi cantly affected by the degree of distal implant inclination and the type of nylon inserts.
Lm is recommended to retain overdentures when implants have 5° or 10° distal inclination,
and Le and Ll are recommended with 20° inclination to maintain high axial and nonaxial
retention after wear.

Elsyad M, Eltowery S, Gebreel A

Peri-implant strain around mesially inclined two-implant-retained mandibular
overdentures with Locator attachments

Journal of Oral Science, Vol. 59, No. 4, 483-490, 2017

This study aimed to evaluate the periimplant strain around mesially inclined implants used to
retain mandibular overdentures with Locator resilient attachments. Four mandibular edentulous
acrylic resin models received two implants in the canine areas with 0°, 5°, 10°, and 20° mesial

Overdentures were connected to the implants using Locator attachments. Pink nylon inserts
(light retention) were used for all implant inclinations, and red inserts were used for 20° inclination
(20°red). Four strain gages were bonded on the mesial (M), distal (D), buccal (B), and lingual
(L) surfaces of each implant. Peri-implant strains were measured during bilateral and unilateral
loading. The 20° inclination showed the highest strain, followed by 10° and 5°, and both 0° and
20°red presented with the lowest strain. Site D was associated with the highest strain, followed
by M, B, and L, which showed the lowest strain values. Unilateral loading and the loading side
presented with signifi cantly higher strain values than bilateral loading and the nonloading side,
respectively. Hence, in this study, strains around the two-implant-retained overdentures with
Locator attachments increased with increases in mesial implant angulation, except when red
male inserts were used.

Elsyad M, Abid K, Elkhalek E

Effect of Buccal Implant Inclination on Stresses Around Two-Implant–Retained
Overdentures with Resilient Stud Attachments

The International Journal of Oral & Maxillofacial Implants April 2017

This study aimed to evaluate the effect of buccal implant inclination on stresses around
two-implant–retained overdentures with resilient stud attachments.
Materials and Methods:
Four acrylic models representing a mandibular edentulous ridge were constructed. For each
model, two implants were placed at canine areas. Models were classified into four types
according to the degree of buccal implant inclination: Group I (GI, 0 degrees), Group II
(GII, 10 degrees), Group III (GIII, 20 degrees), and Group IV (GIV, 30 degrees). Overdentures
were connected to the implants with Locator attachments. Regular light-retention inserts were
used for all groups, and extended range inserts were also used for GIV (GIVext), making a fifth
comparison group. Four strain gauges were bonded at the buccal, lingual, mesial, and
distal surfaces of each implant to monitor the stresses during bilateral and unilateral
load application.
Tensile stresses were recorded at distal and lingual gauges, and compressive stresses
were recorded at mesial and buccal gauges for all groups. GIV recorded the highest
stresses, followed by GIII, GII, GIVext, and GI. Distal position recorded the highest stresses,
followed by lingual, mesial, and buccal. Nonloading side was associated with significantly
higher stresses than loading side.
The peri-implant stresses increase as the buccal implant inclination increases when resilient
stud attachments are used for implant overdentures. Therefore, it is recommended to insert
the implants parallel to each other to decrease peri-implant stresses. However, when buccal
inclination is inevitable due to anatomical limitations, it should be limited to 10 degrees for
standard nylon inserts, or extended range inserts are recommended.

Elsyad M, Hammouda N

Expansion of Mandibular Knife-Edge Ridge and Simultaneous Implant
Placement to Retain Overdentures: One-Year Clinical and Radiographic Results of a
Prospective Study

Clinical Implant Dentistry and Related Research Volume 19, Number 1, 2017

The aim of this study was to evaluate and compare the clinical and radiographic outcomes
of two implants placed in expanded mandibular knife-edge ridge and implants placed in
unexpanded ridges to retain overdentures.

Materials and Methods:
Fifteen completely edentulous patients with knife-edge ridges at canine areas of the mandible
received two implants using the ridge expansion technique (study group, SG). Expansion was
performed using piezoelectric corticotomy, and self-threading expanders. The control group
(CG) comprised patients who received two-implant at canine areas without ridge expansion
but were all case matched to SG and served as historical cohort. In both groups, mandibular
overdentures were connected to the implants with Locator attachments 3 months after implant
placement. Clinical (Plaque index; PI, Gingival index; GI, Probing depth; PD, and implant
stability; ISQ) and radiographic (Vertical bone loss; VBL) parameters were recorded at time of
overdenture insertion (base line, T0), 6 months (T6), and 12 months (T12) after insertion.

The cumulative success rates were 100 % and 96.4 % for CG and SG, respectively, without
significant difference between groups. All tested parameters increased significantly with
advance of time in both groups. There was no significant difference in PI, GI, PD, and ISQ
between groups. However, SG recorded significant higher VBL than CG at T6 and T12.

Expansion of mandibular knife edge ridge and simultaneous placement of implants to retain
overdentures is associated with clinic and radiographic outcomes comparable to implants
placed in unexpanded ridges after 1 year. However, long term randomized controlled trials
with sufficient sample size are still needed to ensure the findings of the present study.

Elsyad M, Omran A, Fouad M

Strains Around Abutment Teeth with Different Attachments Used for Implant-
Assisted Distal Extension Partial Overdentures: An In Vitro Study

Journal of Prosthodontics 26 (2017) 42–47

The aim of this study was to evaluate and compare strain around abutment teeth with different
attachments used for implant-assisted distal extension partial overdentures (IADEPODs).

Materials and Methods:
A mandibular Kennedy class I acrylic model (remaining teeth from fi rst premolar to fi rst
premolar) was constructed. A conventional partial denture was constructed over the model
(control, group 1). Two laboratory implants were then placed bilaterally in the fi rst molar areas
parallel to each other and perpendicular to the residual ridge. Three additional experimental
partial overdentures (PODs) were constructed and connected to the implants using ball
(group 2), magnetic (group 3), and Locator (group 4) attachments. Three linear strain gauges
were bonded buccal, lingual, and distal to the fi rst premolar abutment tooth at the right
(loading) and the left (nonloading) sides. For each group, a universal testing device was used
to apply a unilateral vertical static load (50 N) on the fi rst molar area, and the strain was
recorded using a multichannel digital strainometer.

Signifi cant differences between groups and between sites of strain gauges were detected.
Strains recorded for all groups were compressive (negative) in nature. Group 1 demonstrated
the highest strain, followed by group 3 and group 4; group 2 recorded the lowest strain. For
group 2, the highest strain was recorded at the lingual nonloading side. For group 1, group 3,
and group 4, the highest strain was recorded at the buccal loading side.

Within the limitation of the present study, ball attachments used to retain IADEPODs to
the implants were associated with lower strains around abutment teeth than Locator and
magnetic attachments. The highest strain was recorded with conventional partial dentures.

Elsyad M, Setta F, Khirallah A

Strains around distally inclined implants retaining mandibular overdentures with Locator attachments: an in vitro study

J Adv Prosthodont 2016;8:116-24

The aim of the present study was to evaluate, by means of strain gauge analysis, the effect of different implant angulations on strains around two implants retaining mandibular overdenture with Locator attachments.

Materials and Methods:
Four duplicate mandibular acrylic models were constructed. Two implants were inserted in the canine regions using the following degrees of distal inclinations: group I (control); 0o, group II; 10o, group III; 20o, and group IV; 30o. Locator pink attachments were used to connect the overdenture to the implants and Locator red (designed for severely angled implants) was used for group IV (group IVred). For each group, two linear strain gauges were attached at the mesial and distal surfaces of the acrylic resin around each implant. Peri-implant strain was measured on loading and non-loading sides during bilateral and unilateral loading.

For all groups, the mesial surfaces of the implants at loading and non-loading sides experienced compressive (negative) strains, while the distal implant surfaces showed tensile (positive) strains.Group IV showed the highest strain, followed by group III, group II. Both group I and group IV red showed the lowest strain. The strain gauges at the mesial surface of the loading side recorded the highest strain, and the distal surface at non-loading side showed the lowest strain. Unilateral loading recorded signifi cantly higher strain than bilateral loading.

Peri-implant strains around two implants used to retain mandibular overdentures with Locator attachments increase as distal implant inclination increases, except when red nylon inserts were used.

Elsyad M, Mahanna F, Elshahat M, Elshoukouki A

Locators versus magnetic attachment effect on peri-implant tissue health of
immediate loaded two implants retaining a mandibular overdenture:
a 1-year randomised trial

Journal of Oral Rehabilitation 2016 43; 297–305

This study aimed to evaluate peri-implant tissue health of immediate loaded two implants
retaining a mandibular overdenture with either magnetic or locator attachment. Thirty two
completely edentulous patients (20 males / 12 females) were randomly assigned into two groups.
Each patient received two implants in the canine area of the mandible using flapless surgical
technique. Mandibular overdentures were immediately connected to the implants with either
magnetic (group I, GI) or locator (group II, GII) attachments. Peri-implant tissue health was evaluated
clinically in terms of plaque scores (PI), bleeding scores (BI), probing depth (PD), implant
stability (ISQ) and interleukin-1-b (IL-1b) concentrations in periimplant sulcular fluid. PI, BI and
PD were measured at mesial, distal, buccal and lingual surfaces of each implant. Radiographic
evaluation was performed in terms of vertical (VBL) and horizontal (HBLO) alveolar bone loss.
Evaluations were performed 2 weeks (T0), 6 months (T1) and 12 months (T2) after overdenture
insertion. Plague scores, PD, IL-1b, VBL and HBLO increased significantly with time. ISQ
decreased significantly with time. BI showed no significant differences between observation
times. GI recorded significant higher PI, ISQ and IL-1b at T2 compared to GII. GII recorded significant
higher VBL than GI at T2 only. For HBLO, no significant differences between groups were
noted. VBL and HBLO showed a significant positive correlation with PD. Locator attachments for
immediate loaded implants retaining mandibular overdentures are associated with decreased
plaque accumulation, decreased implant stability, decreased interleukin-1b concentration in
peri-implant crevicular fluid and increased perimplant vertical bone loss compared to magnetic
attachments after 1 year.

Elsyad M, Agha N, Habib A

Retention and Stability of Implant-Retained Mandibular Overdentures Using
Different Types of Resilient Attachments: An In Vitro Study

The International Journal of Oral & Maxillofacial Implants 2016; 31:1040-1048

The aim of this study was to evaluate and compare the retention and stability of mandibular
implant overdentures using different types of resilient attachments.

Materials and Methods:
Two implant analogs were inserted in the canine areas of an acrylic edentulous mandibular
model. A metal-reinforced experimental overdenture was constructed and connected to the
implant analogs (on two occasions) using either resilient telescopic or Locator attachments.
Locators were divided into three subgroups according to the degree of retention of the male
nylon insert: Locator extra-light retention (blue insert), Locator light retention (pink insert), and
Locator medium retention (transparent insert). Vertical and oblique (anterior, posterior,
and lateral) dislodging forces were measured at the beginning of the study (initial retention)
and after 540 cycles of denture insertion and removal (final retention).

For all dislodging forces, Locator medium recorded the highest initial and final retention.
Telescopic attachments recorded the lowest retention during vertical and anterior dislodging,
and Locator extra-light recorded the lowest retention during lateral and posterior
dislodging. For all types of Locator attachments, anterior dislodging recorded the highest
initial and final retention, and lateral dislodging recorded the lowest retention. For the
telescopic attachment, posterior dislodgment recorded the highest initial retention, and
anterior dislodging recorded the lowest retention.

After repeated denture insertions and removals, the highest retention and stability were
recorded with Locator medium followed by Locator light. The lowest retention was recorded
with resilient telescopic attachment, and the lowest stability was recorded with Locator

Elsyad M, Elhaddad A, Khirallah A

Retentive Properties of O-Ring and Locator Attachments for Implant-Retained
Maxillary Overdentures: An In Vitro Study

Journal of Prosthodontics 00 (2016) 1–9

To evaluate and compare retentive properties of O-ring and Locator attachments for
implant-retained maxillary overdentures.

Materials and Methods:
Four implant analogs were inserted in canine and second premolar areas of an acrylic
edentulous maxillary model. A metal-reinforced experimental acrylic overdenture was constructed
and connected to the analogs using either O-ring (group I) or Locator (group II)
attachments. Locators were divided into 3 subgroups according the degree of retention of the
patrix nylon insert: Locator extralight retention (group IIa), Locator light retention (group IIb),
and Locator medium retention (group IIc). Vertical and oblique (lateral, anterior, and posterior)
dislodging forces were measured at the beginning of the study (initial retention) and after 540
cycles of denture insertion and removal (final retention).

For vertical, lateral, and anterior dislodging, group IIc recorded the highest initial and
final retention, and group I recorded the lowest retention. For posterior dislodging,
group I recorded the highest retention, and group IIa recorded the lowest retention. For
group II, vertical dislodging recorded the highest initial and final retention, and lateral
dislodging recorded the lowest retention. For group I, posterior dislodging recorded the
highest initial and final retention, and lateral dislodging recorded the lowest retention. For
all dislodging forces (except posterior dislodging), the highest retention loss was recorded
in group I, and the lowest retention loss was recorded in group IIa.

Locator medium attachment was associated with favorable retention during axial (vertical)
and nonaxial (anterior and lateral) dislodging compared to other types of Locator inserts and
O-ring attachments after a simulated 6-month period of overdenture use.

Elsyad M, Elhddad A, Khirallah A

The effect of implant diameter on strain around implants retaining a mandibular
overdenture with Locator attachments: An in vitro study

Dental Materials Journal 2016; 35(6): 938–945

This study evaluated the effect of implant diameter on strain around implants retaining
mandibular overdentures with Locator attachments. Three mandibular acrylic resin models were
constructed with 2 implants inserted in canine areas and classified according to implant diameter
into 3 groups: large (4.2 mm), medium (3.7 mm), and small (3.3 mm) diameter implants.
Duplicate dentures were connected to the implants with Locator attachments. Four strain
gauges were bonded to the acrylic resin at mesial, distal, buccal and lingual surfaces of each
implant and strain was measured at loading and non-loading sides during 1st premolar and
1st molar loading. Small and large diameter implants recorded the highest and the lowest
strain, respectively. Buccal and lingual sites recorded the highest strain, and mesial site recorded
the lowest. First premolar loading recorded significant higher strain than first molar loading.
The largest possible implant diameter is recommended to minimize strains around implants
retaining mandibular overdentures with Locator attachments.

Elsyad M, Errabti H, Mustafa A

Mandibular Denture Base Deformation with Locator and Ball Attachments of
Implant-Retained Overdentures

Journal of Prosthodontics 25 (2016) 656–664

The aim of this in vitro study was to evaluate and compare mandibular denture base
deformation between ball and Locator attachments of implant-retained overdentures.

Materials and Methods:
An experimental acrylic model covered with resilient silicone mucosal simulation was
constructed. Two laboratory implants were placed in the canine areas of the model. Two
duplicate experimental overdentures were constructed and connected to the implants with
either ball (GI) or Locator (GII) attachments. To measure overdenture strain around the
attachments, 3 strain gauges were attached to the lingual polished surface of the overdentures
opposite to the right implant (loading side) 2 mm above the attachment level (Ch1), at
the attachment level (Ch2), and 2 mm below the attachment level (Ch3). Another 3 gauges
were bonded opposite to the left implant (non-loading side) in the same manner (Ch6, Ch7,
and Ch8). To measure strain at the midline of the overdentures, two strain gauges were
attached in the midline at 5 mm intervals (Ch4 and Ch5). A universal testing device was
used to deliver vertical static load of 50 N unilaterally and bilaterally to the first molar area to
measure strain using a multi-channel digital strain meter.

During bilateral load application, GII recorded higher compressive strains than GI at the
majority of channels. During unilateral load application, GI recorded higher tensile strains at
Ch1, Ch2, and Ch3, and GII recorded higher strains than GI at Ch6, Ch7, and Ch8. During
bilateral loading the highest strain was concentrated at Ch5 for both groups. During unilateral
loading, the highest strain was concentrated at Ch2 for GI, and at Ch5 for GII.

Ball attachments for implant-retained overdentures were associated with significant
mandibular denture base deformation over the implants compared to Locator attachments.
Therefore, denture base reinforcement may be recommended with ball attachmentz to
increase fracture resistance of the base.

Elsyad M, Elsaih E, Khirallah A

Marginal bone resorption around immediate and delayed loaded implants
supporting a locator-retained mandibular overdenture. A 1-year randomised
controlled trial

Journal of Oral Rehabilitation 2014 41; 608--618

The aim of this 1-year study was to evaluate and compare crestal bone loss and clinical
outcomes of immediate and delayed loaded implants supporting mandibular overdentures with
Locator attachments. In a randomised controlled clinical trial, 36 completely edentulous patients
(mean age 59.6 years) who desired to improve the stability of their mandibular dentures were
randomly assigned into two groups. Each patient received two implants in the canine area of
the mandible after a minimal flap reflection. Implants were loaded by mandibular overdentures
either 3 months (delayed loading group, G1) or the same day (immediate loading group, G2)
after implant placement. Locator attachments were used to retain all overdentures to the
implants. Peri-implant vertical (VBL) and horizontal (HBLO) bone losses and clinical parameters
[plaque scores (PI), gingival scores (GI), probing depths (PD) and implant stability (ISQ)] were
assessed at time of overdenture insertion (T0), 6 months (T6) and 12 months (T12) after
overdenture insertion. After 12 months of overdenture insertion, two implants (5.5 %) failed
in G2. Vertical bone loss was significantly higher in G2 compared with G1, while HBLO
demonstrated insignificant differences between groups. All clinical parameters (PI, GI, PD and
ISQ) did not differ significantly between groups. Vertical bone loss was significantly correlated
with PD and HBLO. Immediately loaded two implants supporting a Locator-retained mandibular
overdenture are associated with more vertical bone resorption when compared to delayed
loaded implants after 1 year. Clinical outcomes do not differ significantly between
loading protocols.

Botzenhart U, Kunert-Keil C, Heinemann F, Gredes T, Seiler J, Berniczei-Roykó A, Gedrange T

Osseointegration of short titan implants: A pilot study in pigs

Annals of Anatomy 2014 March

Reduced vertical bone level in the implantation area is often considered one of the
limiting factors before implant insertion. Inserting implants of reduced length might
be useful in order to avoid vertical bone augmentation prior to implantation. To the
present day, no official guidelines exist as to the optimal length for these implants. It
is nevertheless well known that the stability of an implant depends primarily on its osseointegration,
which could otherwise be influenced by modifying implant surface texture.
The aim of our study was to evaluate osseointegration in correlation with implant length
and surface texture. Three different variations of titan implants (n = 5) were compared:
two types, each with an acid-etched and ceramic blasted surface, were inserted in the
upper jaw of adult female minipigs at different lengths (tioLogic ST Shorty, 5 mm length;
tioLogic© ST, 9 mm length) and were compared to a control group (tioLogic© ST, 9 mm
length, ceramic blasted surface). Eight weeks after unloaded healing, bone tissue specimens
containing the implants were processed, stained with Masson–Goldner-trichrome
and analyzed histologically. Regardless of implant length and surface texture, new bone
formation with no signs of inflammation could be detected in the area of the threads.
Implants with a modified surface showed no statistically significant difference in boneimplant-
contact (BIC) (tioLogic© ST Shorty, 56.5%; tioLogic© ST; 77.2%), but a statistically
significant difference could be found, when the 9 mm implants were compared to
the control group (BIC 48.9%). Surface modification could positively influence osseointegration
as well as contribute to overcoming the adverse effects of length reduction.

Rahimi A

Numerische Simulation von Knochenumbauvorgängen um zahnärztliche Implantate
mit der Finite-Elemente-Methode

Bonn University Hospital 2013

Zur Untersuchung der Knochenumbauvorgange sind neben klinischen auch biomechanische
Methoden, die den Hauptgegenstand der vorliegenden Arbeit bilden, von besonderer
Bedeutung. Insbesondere numerische Simulationen der Knochenumbauprozesse können
erheblich zum Erkenntnisgewinn über diese Prozesse beitragen. Die Einheilung von Implantaten
ist entscheidend von diesen Prozessen abhängig. Da bei bisherigen Modellen
die spongiöse Knochenstruktur nur sehr bedingt mit der realen Situation vergleichbar
war, und gerade bei der Etablierung neuer numerischer Methoden auf eine geeignete
Validierung geachtet werden muss, wurde im Rahmen der vorliegenden Arbeit mit
der Finite-Elemente-Methode ein komplett neues computergeneriertes Knochenmodell
vorgestellt, welches nicht mehr nur rechnerisch, sondern auch optisch die realen
Knochenumbauprozesse nachbildet. Die Auslenkung der Implantate und die Knochendichte
sind die Hauptkriterien bei der Validierung der Modelle.

Die experimentelle und numerische Untersuchung des Einheilverhaltens zahlreicher
unterschiedlicher Implantattypen diente dabei als Grundlage für die Untersuchungen und
die Modellgenerierung. Dabei wurden mehrere Finite-Elemente-Modelle für die numerischen
Untersuchungen entwickelt. Diese Modelle umfassten verschiedene Komplexitätsgrade,
angefangen bei idealisierten Knochenmodellen über nachmodellierte Präparate bis hin zu
dem idealisiert-realistischen dreidimensionalen Modell, welches sich im Rahmen der FEMSimulation
zum Knochenumbau bildet. In systematischen Simulationen wurden die numerischen
Modelle zur Implantateinheilung entwickelt, optimiert und mit Hilfe experimentell
ermittelter Daten validiert und so konnte ein vergleichbares Verhalten erzielt werden.

Um auch eine Validierung nicht nur der numerischen, sondern auch der experimentell
gewonnenen Ergebnisse zu ermöglichen, waren auch in-vivo-Experimente erforderlich. Aus
früheren Studien ist bekannt, dass sich Rentiergeweihe für diesen Zweck als Tiermodell
besonders eignen, da sie ein sehr ähnliches physiologisches Verhalten zum menschlichen
Kieferknochen aufweisen.

Hierzu war die Entwicklung eines neuartigen Gerätes zur Simulation der im menschlichen
Kiefer auftretenden Belastungen erforderlich. Der dabei entstandene Kausimulator bringt
diese Belastungen als periodische Intervalle mittels eines Druckstempels auf ein im Rentiergeweih
inseriertes dentales Implantat auf. Sein hochgradig optimierter Stromverbrauch erlaubt
auch langfristige autonome Untersuchungen an frei laufenden Tieren. Die regelmassige
Kontrolle und Rekonfiguration mehrerer zeitgleich eingesetzter Kausimulatoren kann über
direkte Funkverbindung zu einem beliebigen Computer erfolgen. Ein Einfangen der Tiere
ist nur für die Implantation der dentalen Implantate in das Geweih notwendig. Dabei wird
ebenfalls der Kausimulator angebracht und in Betrieb genommen. Der Kausimulator konnte
erfolgreich an zwei Tieren getestet und die gewonnenen Daten ausgewertet werden.

Heinemann F, Biffar R, Schwahn C, Mundt T

Bone Level Changes in Dental Implants with Platform-Switched Design After
Immediate and Delayed Placement in the Maxilla

The international Journal of Priodontics & Restaurative Dentistry 2013 May/June, 33(3): 365-372

This study sought to evaluate platform-switched implants for immediate placement. A total
of 136 implants were placed in 58 patients using either an immediate or delayed implant
protocol. Bone level changes of the implants were measured mesially and distally and statistically
analyzed with linear mixed models. No implant was lost. There was no significant
difference between immediate and delayed implants in approximal bone level changes during
the first year (95% confidence interval: –0.10 to –0.01 for immediate versus –0.14 to
–0.07 for delayed implants). Subsequent bone resorption was negligible in both groups. (Int
J Periodontics Restorative Dent 2013;33:365–372. doi: 10.11607/prd.1276)

Hasan I, Keilig L, Stark H, Bourauel C

Biomechanlical analysis of tioLogic© ST implants

Poster Bonn University Hospital 2013

The maximum stresses and strains of the new implants with self-tapping threads were
comparable to values determined in earlier studies. Moreover, the displacements of the new
implants were even smaller than the current implants and the biomechanical properties of
the analysed implants were positively improved by integrating the self-tapping threads.

Heinemann F, Hasan I, Schwahn C, Bourauel C, Mundt T

Bone Level change of extraction sockets with Bio-Oss collagen and implant
placement: A clinical study

Annals of Anatomy 2012 November 194 (6): 508-512

To compare the reaction of the alveolar bone to the preservation of the extraction socket by
Bio- Oss Collagen with and without combination of implant treatment. To evaluate whether
early implant insertion 8–10 weeks thereafter could be a suitable time point for long term
bone stability around the implant.

A total of 25 patients were divided into three groups: The first group (seven patients) received
Bio-Oss Collagen after extraction and 8–10 weeks later an implant, the second group
(eight patients) received only Bio-Oss Collagen without implantation thereafter, while the
third group was considered as a control (eleven patients), where the sockets healed without
any treatment. The change in the vertical bone level of the alveolar crests were measured
from panoramic radiographs and statistically analysed.

Bone level change was significantly less for Group 1 than Group 3 (P < 0.001), while was not
significantly different for Group 2 and Group 3 (P = 0.23). However, the rate of bone level
change per year was statistically smaller for Group 1 compared to Group 3 (P = 0.019) and
as well as for Group 1 than for Group 2 (P = 0.003), whereas the change per year was not
significantly different for Group 2 vs. Group 3 (P = 0.122).

Bone level preservation of extraction sockets using Bio-Oss Collagen with implantation is
significantly better compared to using Bio-Oss Collagen only and untreated sockets. Implant
insertion 8–10 weeks after extraction is a suitable time point after socket augmentation.

Hasan I, Röger B, Heinemann F, Keilig L, Bourauel C

Influence of abutment design on the success of immediately loaded dental
implants: Experimental and numerical studies

Medical Engineering & Physics 2012 September, 34(7): 817– 825

The aim of the present study was to investigate experimentally and numerically the
influence of a fine threaded- against a roughened-cervical region of immediately loaded
dental implants in combination with straight and 20-angled abutments on the implant
primary stability. A total of 30 implants were inserted in bovine rib-segments, 14 cervically
roughened implants and 16 implants with fine cervical threads. Each implant system
received two abutments, straight and 20-angled. Implant displacements and rotations were
measured using a biomechanical measurement system. Subsequently, eight samples were
selected for geometrical reconstruction and numerical investigation of stress and strain
distributions in the bone by means of the finite element method. Experimentally, both
implant systems showed similar behaviour with the straight abutments concerning displacements
and rotations. However, fine threaded implants showed much less displacement and
rotation against roughened implants when angled abutments were considered. Numerically,
stresses were within 35–45 MPa in the cortical bone for both implant systems. The strains
showed highest values within the spongious bone with the roughened implants connected
to angled abutments. The results indicate that implants with fine cervical threads could be
recommended in particular with angled abutments. The outcomes of this study are currently
confirmed by long-term clinical investigations.

Kunert-Keil C, Gredes T, Richter D-U, Szyba M, Dominiak M, Gedrange T

The survival and proliferation of fibroblasts on ceramic implants: an in vitro study

Biomedizinische Technik/Biomedical Engineering 2012 January, 57(1): 11-15

To improve osseointegration, different possible dental implant surface modifications, e.g.,
alterations of surface chemistry and roughness, have been developed. The purpose of this
study was to examine the in vitro biocompatibility of newly designed zirconium implants
with different surface modifications in comparison with commercially available zirconium
and titanium implants. Therefore, cell viability and proliferation were measured after
21 days and correlated with surface structures. In the presence of new ceramic implants
with an “mds (blasted/etched)” and a “blasted” surface, cell viability was 1.29- and 1.26-
fold increased, respectively, compared to untreated cells, whereas cell viability was unchanged
in the presence of reference implants and new ceramic implants with an “etched”
surface. The cell viability findings correlate with the results of the cell cytotoxicity assay. The
etched implants showed a surface with high roughness and heterogeneity, whereas the
mds and blasted implants showed a similar, very rough-textured homogenate surface. The
in vitro biocompatibility of two new ceramic implants was significantly better in comparison
with the tested reference ceramic and titanium implants. The good biocompatibility may be
attributed to the homogenous surface of these implants, and these surfaces might hasten

Hasan I, Heinemann F, Keilig L, Bourauel C

Simulating the trabecular bone structure around dental implants: a case presentation

Biomedizinische Technik/Biomedical Engineering 2012 January, 57(1): 17-19

The effect of bone remodeling on the long-time success of dental implants is becoming critical
for implant design and presurgical assessments. This study applies a previously presented
remodeling simulation scheme on a computer tomography (CT)-based finite element model.
The CT data of a dental implant at the upper right central incisor region 6 years after implant
insertion was used. The time-dependent density change of the trabecular bone after osseointegration
was studied. The trabecular structure, by means of density distribution, around
the implant showed similarities to the CT images at many regions.

Bourauel C, Aitlahrach M, Heinemann F, Hasan I

Biomechanical finite element analysis of small diameter and short dental implants:
extensive study of commercial implants

Biomedizinische Technik/Biomedical Engineering 2012 January, 57(1): 21-32

In recent years, mini and short dental implants have become increasingly popular as treatment
alternatives for patients in whom the bone is unsuitable for a standard implant. As yet,
no detailed scientific analysis of the mechanical and biomechanical impact of the reduced
diameter and length of these implants has been published. We analysed 21 commercially
available implants (13 mini, eight short) with respect to material behaviour and load transfer
to the alveolar bone, using finite element (FE) analysis. Following μ CT scanning and geometry
reconstruction, FE models of mini implants and short implants were inserted into
idealised bone segments. Mini implants were analysed in the anterior mandibular jaw region
at a force of 150 N under immediate loading, using a contact analysis in the FE software
package Marc Mentat 2007. Short implants were inserted in posterior bone segments and
analysed in the osseointegrated state at an occlusal force of 300 N. Von Mises stresses (up
to 1150 MPa) in mini implants partly exceeded the ultimate strength. Implant diameter and
geometry had a pronounced effect on stresses in the cortical plate (up to 266 MPa). Strains
in spongy bone and stresses in cortical bone around short implants were markedly increased
compared to those in standard implants. An increased risk of bone damage or implant
failure may be assumed in critical clinical situations.

Bräuer L, Schicht M, Stengl C, Heinemann F, Götz W, Scholz M, Paulsen F

Detection of surfactant proteins A, B, C and D in human gingiva and saliva

Biomedizinische Technik/Biomedical Engineering 2012 January, 57(1): 59-64

The oral cavity along with the teeth and the surrounding gingival epithelium is open to the
oral environment and is thus exposed to multiple microbiological and pathogenic influences.
To prevent permanent inflammatory processes such as gingivitis or parodontitis, an efficient
defense system is necessary to sustain the physiological function of the oral cavity. Surfactant
proteins (SPs), originally known from pulmonary tissue, are important players of the immune
system and, beyond this, support the stability and rheology of gas or fluid interphases.

Here we evaluate the expression and presence of SPs (SP-A, SP-B, SP-C, and SP-D) in human
gingiva and saliva. Messenger RNA expression of SP-A, SP-B, SP-C, and SP-D was analyzed
by reverse transcriptase-polymerase chain reaction in healthy gingiva. The distribution of all
four SPs was further determined with monoclonal antibodies using Western blot analyses
and immunohistochemistry in healthy and pathologically changed tissues samples obtained
during biopsies and in saliva of volunteers.

Our results indicate that SP-A, SP-B, SP-C, and SP-D are peptides produced by healthy gingiva
that reveal a changed expression pattern in cases of gingival disease.

Based on the known direct and indirect antimicrobial effects, SP-A and SP-D appear to be
involved in immune defense within the oral cavity especially in direct proximity of teeth.
Gingiva affected by bacterial inflammation (gingivitis) seems to increase expression of SPs.
As a result, the rheology of saliva may be changed especially at the crest of the gingival
epithelium to support the function of antimicrobial substances present in saliva. Furthermore,
SPs could assist in pellicle formation on teeth, which needs to be determined in further

Botzenhart UU, Henningsen A, Quaas S, Luthardt RG, Proff P, Spassov A, Gedrange T

3D assisted morphological analysis of lingual upper central and lateral incisor surfaces

Biomedizinische Technik/Biomedical Engineering 2012 January, 57(1): 71-77

To determine the lingual surface morphology of central and lateral upper incisors evaluating
constant morphological regions for better adhesion of industrial prefabricated lingual

Material and methods:
A total of 102 randomly selected patients at the end of the first phase of second dentition
with intact central and lateral upper incisors participated in this study. After impression taking
and cast model preparation, 3D laser scans of the lingual surface of the upper central
and lateral incisors were taken (Laserscan 3D ® , Willytec, Munich, Germany), digitalised,
and transferred into CAD software to analyse the surface morphology by superimposition.
For better comparison of morphological variations and determination of the most constant
lingual regions, the surface was divided into five parts: incisal edge, mesial ridge, lateral
ridge, cingulum, and medial sector. Statistical analysis was performed by the paired t -test.

Statistically significant differences were found in all surfaces, with cingulum as the most
inconstant region. The most constant region was the medial sector and the mesial ridge.

As expected, the lingual surface underlies a high intra-individual variation complicating industrial
prefabricated lingual brackets adhesion. However, the mesial ridge and the medial
sector seem to be the most constant regions within intra-individual morphological variations.

Hasan I, Heinemann F, Bourauel C

The Relationship of Bone Resorption around Dental Implants to Abutment Design:
A Preliminary 1-Year Clinical Study

The International Journal of Prosthodontics 2011 September, 24(5): w.p.

The influence of abutment design on bone resorption around immediately loaded and
osseointegrated implants used to support fixed partial prostheses was investigated in a
1-year study. One hundred ten implants were placed in 24 anterior partially edentulous
maxillae. The probing depths of each implant were measured 6 and 12 months after
abutment placement and analyzed statistically. Total probing depth was 1.75 ± 0.75 mm.
There were significant differences between non- and submerged implants with angled
abutments and between submerged implants with straight and angled abutments. No
significant differences were observed between non- and submerged implants with straight
abutments and between nonsubmerged implants with straight and angled abutments.
Bone resorption around dental implants is influenced by the abutment design and the
associated implantation protocol.

Heinemann F, Hasan I, Schwahn C, Biffar R, Mundt T

Crestal bone resorption around platform-switched dental implants with fine
threaded neck after immediate and delayed loading

Biomed Tech (Berl). 2010 December, 55(6): 317-321

Abstract Bone resorption and peri-implantitis are some of the most important problems of
dental implantology. The implant macrodesign might decrease initial bone loss. The aim
of this longitudinal study was to investigate crestal bone loss around screw type, tapered
implants showing a fine threaded neck and platform switching design. In 32 patients of a
dental practice, 147 maxillary implants with a diameter of 3.7 mm and 4.2 mm were placed and
loaded according to clinical criteria. Immediate loading was exclusively performed in 3.7 mm
diameter implants when adequate splinting and implant stability could be guaranteed
(n=50). The remaining implants were loaded delayed. The bone level change was measured
mesially and distally of the implant shoulder using follow-up X-rays and calculated per year in
a linear mixed model. Bone resorption was low in all groups (3.7 immediate: -0.06 mm/year;
3.7 delayed: -0.16 mm/year; 4.2 delayed: -0.09 mm/year) after a mean follow-up period of
1.6 years (0.5-3.2 years). Based on the results of this study, it can be concluded that this
implant macrodesign showed negligible bone resorption for all loading times. Immediate
loading seems to be a reliable treatment option in the maxilla when clinical criteria are

Hasan I, Heinemann F, Aitlahrach M, Bourauel C

Biomechanical finite element analysis of small diameter and short dental implant

Biomedizinische Technik/Biomedical Engineering 2010 December, 55(6): 341-50

Short and mini dental implants have been widely used as treatment alternatives in certain
selected clinical situations. However, a profound scientific analysis of the mechanical and
biomechanical impact of the reduced length and diameter of these implant geometries
has not been published until now. Using finite element analysis, a series of different
experimentally designed short and mini implants have been analysed with regard to
their load transfer to the alveolar bone and have been compared to respective standard
commercial implants. Mini implants have been inserted in an idealised bone bed representing
the anterior mandibular jaw region and loaded with a force of 150 N. An immediate loading
condition was assumed and analysed using the contact analysis option of the FE package
MSC.Marc/Mentat. Short implants were inserted in an idealised posterior bone segment and
loaded in osseointegrated state with forces of 300 N. Clearly increased bone loading was
observed for the short and mini dental implants compared with standard implants, clearly
exceeding the physiological limit of 100 MPa. The determined biomechanical characteristics
could explain the slightly increased failure rate of short and mini dental implants.

Hasan I, Heinemann F, Reimann S, Keilig L, Bourauel C

Finite element investigation of implant-supported fixed partial prosthesis in the
premaxilla in immediately loaded and osseointegrated states

Comput Methods Biomech Biomed Engin. 2010 July, 27: 1 (epub ahead of print)

The aim of this study was to gain insight into the behaviour of the stresses and strains
at the bone-implant interface of an implant-supported fixed partial prosthesis (FPP) in the
premaxilla under immediate loading and osseointegrated conditions. Finite element models
of a four-unit FPP were generated. An extreme condition was simulated, using only two
immediately loaded implants in order to derive recommendations for possible clinical
application. Straight and 20 degrees-angled abutments and bonded or sliding contact
between the bridge and abutment were simulated. In addition, two models were
generated with two completely osseointegrated implants. A 150 N load to the prosthesis
at a 45 degrees angle to the long axis of each implant was applied. Minor differences were
observed in implant displacements, stress and strain distributions of the two abutment
designs. However, bone loading exceeded the physiological limits, including a risk of
bone atrophy. A considerable decrease in implant displacements and bone loading was
observed in the osseointegrated cases. An FPP supported by only two implants cannot be
recommended for immediate loading.

Lindigkeit J, Sterzl T

2 Millionen Mal kraftvoll zubeißen

CADFEM Infoplaner 2010 Februar: 18-19

tioLogic© ist ein innovatives Implantatsystem der Firma Dentaurum, in dem langjährige
klinische und prothetische Erfahrungen und zukunftsweisende implantologische Aspekte
umgesetzt sind. Das Implantatdesign hat ein mehrstufiges Entwicklungskonzept durchlaufen,
bei dem FEM-Berechnungen mit dem Programm ANSYS wichtige Informationen geliefert
haben, um den Dauerfestigkeitsnachweis nach DIN EN ISO 14801 auf Anhieb zu bestehen.

Ofer M, Sieg P, Jacobsen HC, Hakim SG

Implantatstabilität im Oberkiefer bei reduziertem Knochenangebot – Vergleich von
dynamischen Messwerten und Periotest®

Poster Universitätsklinikum Schleswig-Holstein Campus Lübeck 2010

Die Implantatstabilität im Oberkiefer lässt sich bei reduziertem Knochenangebot während
der Implantatinsertion häufig nur abschätzen. Neben der Knochen-beschaffenheit sind
auch das Implantatmaterial, die Implantatbeschichtung, das Implantatdesign und das
Einheilverhalten von großer Bedeutung. Spannungen und Verzerrungen des Knochens in der
Umgebung enossaler Implantate spielen für deren Langzeiterfolg eine entscheidende Rolle
und sind stark von den Implantateigenschaften abhängig.

In dieser Arbeit wird eine Methode vorgestellt, bei der durch Aufzeichnung des Drehmomentverlaufs
während der maschinellen Insertion die Primärstabilität quantifiziert
werden kann.

Heinemann F, Bourauel C, Hasan I, Gedrange T

Influence of the implant cervical topography on the crestal bone resorption and
immediate implant survival.

Journal of Physiology and Pharmacology 2009 December, 60 (Suppl 8): 99-105

The aim of the study was the investigation of the survival rate of immediate implants
in addition to the evaluation of the level of the alveolar bone around the neck region of
immediately placed implants of different macrodesigns. To address the question whether
the „biological“, highly polished area of the implant neck is more associated with crestal
resorption than the rough neck region, the influence of the surface characters of the
implant cervical region was studied. The survival rate of 129 implants from 52 patients was
evaluated on different time points after immediate implantation. The level of peri-implant
bone contacts to the implant border from 24 implants, which included implants types Tiolox®,
NobelReplace Tapered and PrimaConnex Tapered, was measured radiographically in seven
patients who received immediate implants followed by a healing period of 3-6 months.
Various periods from the time of insertion were considered for the measurement depending
on the clinically available data. No differences in the status of the alveolar crest around
highly polished and roughened cervical-implant regions were observed in the seven
patients. The most noticeable resorption was detected in the distal margin of the
alveolar crest. The present study shows that highly polished- or roughened neck implants are
inserted into a fresh extraction socket do not differ significantly in the clinical and
radiographical outcomes after various post-operative periods.

Heinemann F, Mundt T, Biffar R, Gedrange T, Goetz W

A 3-year clinical and radiographic study of implants placed simultaneously with
maxillary sinus floor augmentations using a new nanocrystalline hydroxyapatite.

Journal of Physiology and Pharmacology 2009 December, 60 (Suppl 8): 91-97

The aims of this case series was to evaluate the success rate of implants and their
restorations, the sinus bone graft resorption, and the marginal bone loss around the
implants when nanocristalline HA embedded in a silica matrix was exclusively used as
grafting material. In 13 partially edentulous patients of a private practice having missing
teeth in the posterior maxilla and a subantral bone height between 3 and 7 mm, 19 sinus
augmentations (100 % NanoBone, Artoss, Rostock, Germany) by the lateral lift technique
were performed. The implants (Tiolox®/Tiologic® Implants, Dentaurum, Ispringen, Germany)
were simultaneously placed. After 6 to 9 months 37 implants were restored with fixed
dental prostheses. The clinical evaluation included peri-implant parameters, periotest
measurements and the restorations. The radiographic bone heights over time were
estimated with linear mixed models. The implant success rate was 100 % after three years.
The periotest values (between -7 and -6) after implant abutment connection indicated a
solid osseointegration. The mean rates of the marginal bone loss over the first year were
higher (mesial: -0.55, distal: -0.51 mm) than the annual rates thereafter (mesial: -0.09 mm,
distal: -0.08 mm). The mean rates of changes in the total bone height were neglectable
(<0.2 mm) and not significant. The prosthodontic and esthetic evaluation revealed a
successful outcome. Within the limits of this clinical report it may be concluded that
maxillary sinus augmentation using 100 % nanocristalline HA embedded in a silica matrix to
support implants is a reliable procedure.

Rahimi A, Bourauel C, Jager A, Gedrange T, Heinemann F

Load transfer by fine threading the implant neck – a FEM study

Journal of Physiology and Pharmacology 2009 December, 60(Suppl 8): 107-12

Osseointegration of dental implants up-to-date is a well-confirmed phenomenon, however
the long-term stability and integrity of the bone and soft tissue collar is under discussion.
A homogenous distribution of the bone loading is a prerequisite for bone modelling and
preservation in the neck area while overload must be avoided. Based on the finite element
method (FEM) models of implants without and with a fine thread (implant types Tiolox®
and tioLogic®) with surrounding bone were generated and analysed using the FE program
system MSC.Marc/Mentat. The alveolar bone was considered to be an idealized segment
with a cortical bone thickness of 2 or 3 mm, respectively with an enclosed spongy bone. The
implants were loaded with forces up to 300 N in two different directions, in the first case
with a purely vertical force and in other case with an additional lateral force component
with an angle of 45 degrees with respect to the occlusal plane. The deflections of the
implants ranged from 0.004 to 0.017 mm in the load direction, depending on the implant
diameter and the cortical bone thickness. When considering a physiological vertical load of a
maximum of 100 N, the highest strains were about 2100 micro strain in the spongy
bone. Within the fine thread in the neck area of the implant, the maximum stresses were
increased in the cortical bone by 3 %. The improvement of implant anchorage in the cortical
bone reduced the strains in the spongious bone, at the same time there were no additional
stress peaks visible at the fine thread region.

Heinemann F, Mundt T, Pfeifer M, Götz W, Bourauel C, Biffar R

DVT, 3D-Planung und Navigation im Rahmen implantologischer Behandlungen

Digital Dental.News 2009 Dezember, 3(9): 56-63

In den vergangenen Jahren hat sich das Spektrum technischer, insbesondere computergestützter
Verfahren für die zahnmedizinische Diagnostik und Therapie dank der rasanten
Weiterentwicklung der Computertechnik hinsichtlich Hard- und Software sowie
Speichermöglichkeiten etc. enorm ausgedehnt. In Rahmen der Implantologie tragen dreidimensionale
Darstellungs- und Planungsmöglichkeiten zu einer Erweiterung der möglichen
Indikationen und somit zu einer Steigerung der Anzahl von Implantatversorgungen bei.
Gleichzeitig erhöht sich der Bedarf an dreidimensionaler Bildgebung für Kontrollen und

Canullo L, Pataccia O, Sisti A, Heinemann F

Implant Restoration 3 months after One Stage Sinus Lift Surgery in Severely
Resorbed Maxillae: 2-Year Results of a Multicenter Prospective Clinical Study

Clinical Implant Dentistry and Related Research 2009: 107-12

Objectives: This multicenter prospective study was aimed to clinically evaluate implant
behavior inserted in severely resorbed maxillae and restored 3 months after sinus grafting.

Materials and Methods: In three clinical centers, 67 totally rough wide diameter implants
were inserted during 30 consecutive sinus lifts. Computed tomography and panoramic
analysis were preoperatively requested for each patient. Sinus grafting was performed using
a nano-crystalline hydroxyapatite sole bone filler; no membrane was used to cover the
buccal window. Preoperative residual bone height ranged between 1–4 mm (mean value:
2.70 mm, standard deviation [SD]: 0.9 mm). Uncovering procedure was carried out
following 3 months of healing; 2 weeks later, a definitive restoration was seated using
platform switching concept. To monitor stability changes, resonance frequency analysis
was performed and implant stability quotient (ISQ) values were collected at the first surgery
(baseline, T0), at the abutment connection (T1), and at 2-year follow-up (T2). To measure
bone changes, patients underwent panoramic analysis after 2-year follow-up. The image
analysis software calculated the grafted bone height changes at level of implant site
comparing pre-operative and follow-up panoramic films; the software compensated for
eventual radiographic distortion.

Results: Mean ISQ value was 35.7 (SD: 8.8) at baseline, 66.61 (SD: 4.76) at T1, and 77.9
(SD: 4.7) at T2. Statistically significant differences (p 2 0.005) regarding ISQ mean values
were found between T1 and T0, as well as between T1 and T2. After 24 months of
functional loading, only two implants were lost (cumulative survival rate: 97 %). During the
same observation period, the mean value of radiographic vertical height of grafted sinus
was 13.75 mm (SD = 1.3 mm), with a mean gain of 11 mm.

Conclusions: Within the limits of this study, despite of preoperative residual bone height
ranging 1 to 4 mm and absence of the membrane covering the buccal bone wall, maxillary
sinus lift restoration 14 weeks after first surgery seems to be a reliable procedure using
totally-rough surfaced implants restored using platform switching concept and
nano-structured hydroxyapatite as sole bone filler.

Rahimi A, Heinemann F, Jäger A, Bourauel C

Biomechanical studies on the influence of variations in the geometry of the
tioLogic© implant

Poster Bonn University Hospital 2009

The maximal stresses in the cortical bone were increased by up to 3 % by the fine thread
on the implant next; strains in the cancellous bone were slightly reduced by the fine thread.
This indicates that the fine thread increases the load transmission in the cortical bone. This
should have a positive impact on the biomechanical properties and healing process.

Bourauel C, Reimann S, Rahimi A, Keilig L

Anwendung numerischer Methoden in der Zahnheilkunde – Computersimulation
kieferorthopädischer, implantologischer und prothetischer Behandlungsaufgaben
(Teil II)

Digital Dental.News 2007 Oktober, 1(7): 6-12

Im ersten Teil dieses Beitrags wurden die Einsatzmöglichkeiten numerischer Methoden in
der zahnärztlichen Behandlungsplanung auf der Basis von dreidimensionalen Patientendaten
vorgestellt. Dabei wurde zunächst das Grundprinzip der Finite-Elemente-Methode
(FEM) erläutert, bei der ein Körper in eine Vielzahl kleiner mechanischer Elemente zerlegt
wird. Unter Annahme bestimmter biomechanischer Bedingungen können mit dieser
Methode auch zahnmedizinische Fragestellungen simuliert werden. Die Anwendung auf die
kieferorthopädische Behandlungsplanung wurde bereits ausführlich beschrieben. In diesem
zweiten Teil folgen nunmehr Beispiele aus der zahnärztlichen Prothetik und der zahnärztlichen

Bourauel C, Reimann S, Rahimi A, Keilig L

Anwendung numerischer Methoden in der Zahnheilkunde – Computersimulation
kieferorthopädischer, implantologischer und prothetischer Behandlungsaufgaben
(Teil I)

Digital Dental.News 2007 September, 1(6): 14-18

Im Verlauf der letzten zwanzig Jahre haben computergestützte Methoden zur Unterstützung
der Behandlungsplanung verstärkt Einzug in alle medizinischen Fachbereiche gehalten.
Auch in der Zahnmedizin ist der Trend hin zu computergestützter Behandlungsplanung
offensichtlich. Ein klassisches Beispiel, das mittlerweile auch den meisten zahnmedizinischen
Patienten wohlbekannt sein dürfte, ist sicher das CAD/CAM-System CEREC (Sirona Dental
Systems, D-Bensheim). Hierbei wird der präparierte Zahn mittels eines hochauflösenden
Scanners intraoral in einen Computer eingelesen. Anschließend erfolgt mittels Grafikprogramm
die dreidimensionale Rekonstruktion von Zahn und Kavität sowie interaktiv
das Design z. B. des Inlays. Anschließend erfolgt in einem CAM-Schritt (Computer Aided
Manufacturing) die rechnergestützte Herstellung des Inlays.

Mundt T

TIOLOX® – Klinische Erfolgsbewertung von Implantaten und Suprastrukturen nach
5 bis 10 Jahren


Das Ziel der Untersuchung bestand in einer retrospektiven Langzeitstudie anhand der
Karteieintragungen, um die Überlebensrate der in der Praxis von Dr. Hotz in Sigmaringen
inserierten Implantate des Tiolox® System der Firma Dentaurum, Ispringen zu ermitteln. Die
Implantate werden von Dr. Hotz in den Jahren 1990 bis 1998 inseriert und größtenteils
auch prothetisch versorgt. Gleichzeitig wurden für eine Querschnittsuntersuchung 250
randomisierte Patienten einbestellt (Bruttostichprobe), um den gegenwärtigen Zustand der
Implantate inklusive der Suprakonstruktion zu evaluieren. Die Untersuchung wurde durch
Mitarbeiter und eine Promovendin der Poliklinik für Zahnärztliche Prothetik und Werkstoffkunde
der Ernst-Moritz-Arndt-Universität Greifswald vorbereitet und durchgeführt.

Von den einbestellten Patienten waren inzwischen 20 verstorben du 33 unbekannt
verzogen. Abzüglich dieser neutralen Ausfälle beläuft sich die Nettostichprobe auf 197
Patienten. Von diesen konnten 159 (94 Frauen, 65 Männer) mit einem durchschnittlichen
Alter von 53 Jahren untersucht werden. Die Response beträgt 80,7 %. Zum Kontrolltermin
wurde eine aktuelle Anamnese und ein Patientenzufriedenheitsbogen erhoben sowie eine
klinische und röntgenologische Untersuchung durchgeführt.

Insgesamt wurden 663 Tiolox®-Implantate inseriert, davon 367 im Oberkiefer und 296
im Unterkiefer. Jeweils ein Implantat pro Patient wurde klinisch untersucht, um die
Unabhängigkeit der Beobachtungen zu gewährleisten.

Die Implantathygiene war insgesamt gut (Grad 0-1: 67 %). Der Mittelwert der maximalen
Sondierungstiefen pro Implantat beträgt 4,51 mm, im Interquartilbereich schwankt sie
zwischen 3 und 6 mm und ist höher als in vergleichbaren Untersuchungen, die jedoch
die mittele Taschentiefe in ihrer Analyse berücksichtigt haben. Das Symptom Blutung auf
Sondierung war nur bei 26 von 152 Implantaten negativ. Daraus resultierten auch relativ
hohe Gingivalindexwerte entsprechend anderer Studien mit höherer Liegedauer. Bei
über der Hälfte der Implantate war keine fixe Mukosa vestibulär oder oral vorhanden. Ein
Regressionsmodell, das den Einfluss auf periimplantäre Parameter untersuchte, ergab jedoch
lediglich Korrelationen zwischen Plaque und den periimplantären Entzündungszustand.

Die Knochenabbaurate wurde longitudinal berechnet, sofern ein Anfangsröntgenbild
vorhanden war. Fehlende Werte wurden zu Verlaufs-OPGs linear interpoliert. Der Knochenabbau
im ersten Jahr liegt danach mit einem Median von 0,14 mm bzw. einem Mittelwert
von 0,34 mm unter den Werten vergleichbarer Studien. Danach befindet sich die durchschnittliche
jährliche Rate von 0,1 bis 0,2 mm im Größenbereich anderer Systeme. Teilweise
wurde sogar eine Knochenapposition gemessen. Ein Zusammenhang zwischen Sondierungstiefe
und aktueller Knochenhöhe wurde statistisch ermittelt. Das ist ein Hinweis dafür, dass
die Sondierungstiefe eher von der Schleimhautdicke und vom Knochenabbau abhängt als
vom Entzündungsgrad, da die Parodontalfasern fehlen.

370 der 663 Implantate waren festsitzend versorgt (rein implantatgetragene- und Verbundbrücken,
43 Einzelkronen) und 293 herausnehmbar außer einer abnehmbaren teleskopierenden
Brücke mit Stegprothesen. Die Komplikationsrate (Schraubenlockerungen,
Aufbaulockerungen, Keramikabplatzungen, Reparaturen, Neuanfertigungen) war im Vergleich
zu anderen Implantatstudien, insbesondere mit dem Brånemarksystem, sehr niedrig.
Das spricht für sichere und ausgereifte Prothetikkomponenten und für die Stabilität der
Implantat-Aufbau-Verbindung, obwohl hier ebenfalls auf ein Außenhexagon geschraubt
wird. Eine entsprechend exakte zahntechnische Verarbeitung ist ebenfalls Voraussetzung
für die Bewährung.

Die Patientenzufriedenheit mittels einer 10 cm-Skala von 0 (sehr zufrieden) bis 10 (völlig unzufrieden)
ist sowohl mit den Implantaten als auch mit den Suprakonstruktionen sehr hoch.
Die Patienten kennen in der Regel den Versorgungszustand ohne Implantate und lernen
die Vorteile mit Implantaten schätzen. Alle außer einem Patienten würden sich wieder einer
derartigen Therapie unterziehen, sogar diejenigen mit Implantatverlusten.

Die Kaplan-Meier-Schätzung der Überlebensrate für alle Implantate ergab einen 5-Jahres-
Wert von 95,9 % und für 10 Jahre 91,8 %. Damit ist das kumulative Überleben im Vergleich
zu anderen Studien sehr hoch. Im Oberkiefer (89 %) gehen die Implantate häufiger und
eher verloren als im Unterkiefer (96 %). Dabei ist im jeweiligen Kiefer der Seitenzahnbereich
mehr betroffen als der Frontzahnbereich. Bei Männern beträgt das kumulative Überleben
der Implantate nach 10 89,5 % und bei den Frauen 94,2 %. Die Art der Suprakonstruktion
spielt eine untergeordnete Rolle. In der Cox-Regression hat sich das Rauchverhalten der
Probanden als einzige signifikante Variable auf die Überlebensrate herausgestellt. Patienten,
die 40 Jahre lang rauchen, haben das 5,5fach erhöhte Risiko eines Implantatverlustes. Die
10-Jahres-Implantatüberlebensrate beträgt bei ehemaligen Rauchern 90,4 % und bei Nichtrauchern
96,4 %.

Das Tiolox®-Implantat stellt sich innerhalb der Studie als ein sehr stabiles und erfolgreiches
System dar. Dies gilt sowohl für das Implantat selbst als auch für die prothetischen Aufbaukomponenten.

Heinemann F, Mundt T, Biffar R

Retrospective evaluation of temporary cemented, tooth and implant supported
fixed partial dentures

Journal of Cranio-Maxillofacial Surgery, 2006 September, 34 (Suppl 2): 86-91

The aim of this study was to examine the clinical performance of this method, and
determine which temporary cement was the most appropriate.

Dental fixtures (Tiolox® implants GmbH, Germany) were implanted and crown and
bridgework applied in a private practice between 1998 and 2003. Copings made of pure
gold or titanium were permanently cemented onto the prepared teeth. The bridges were
attached with either conventional temporary cements (Zinc oxide/ calcium hydroxide based)
or acrylic/urethane cement (IMProv) both to the copings and to the implant abutments.
Complications were evaluated by a retrospective review in January 2006.

A total of 47 patients (response: 81 %) with 65 fixed partial dentures could be evaluated.
Removal and re-attaching without damage of the dentures was undertaken for the
following reasons: for follow-up examinations (n = 31), colour corrections (n = 15),
cleaning of the dentures (n = 12), treatment of peri-implantitis (n = 2), repair following
ceramic fractures (n = 5), implant failure (n = 1), tooth extractions (n = 2), root canal treatments
(n = 2), occlusal corrections (n = 2), or in the case of abutment loosening (n = 4).
Accidental detachments with conventional temporary cements occurred more frequently
and more rapidly than with IMProv (15 % versus 88.7 % survival rate after four years).

This method for dental implant supported fixed partial dentures is successful and efficient.

Mundt T, Mack F, Schwahn C, Biffar R

Private practice results of screw-type tapered implants: survival and evaluation of
risk factors

Int. Journal of Oral and Maxillofacial Implants 2006 August, 21(4): 607-614

The aims of this study were to examine the long-term survival and the prosthetic treatment
outcome of screw-type, tapered implants placed in a private practice setting and to explore
potential risk factors of implant failures.

In this retrospective analysis of patients treated with endosseous screw-type tapered
implants, data relative to implant placement and failure, implant length, location, prosthetic
treatment, medical history, smoking habits, and oral health behavior were gathered by chart
review and questionnaire. An oral examination was also conducted. Cumulative survival
rates were estimated through Kaplan-Meier methods. Comparisons between subgroups
of patients were made using the log-rank statistical test. The association between several
factors and implant failures was analyzed using Cox regression analyses (random and
dependent models). Differences were considered significant when P < .05.

The survival rate of 663 implants placed in 159 patients (65 men, 94 women; 80.7 % of 197
eligible patients) was 91.8 % after 120 months. Mandibular implants had a higher survival
rate than maxillary implants (96 % versus 89 %, P = .011). The failure rates for implants
were 15.0 % among current smokers, 9.6 % among former smokers, and 3.6 % among
nonsmokers. The differences between nonsmokers, former smokers, and current smokers
were significant (nonsmokers versus former smokers: P = .036, nonsmokers versus current
smokers: P < .001, former smokers versus current smokers: P = .003). Only number of years
of smoking was significantly associated with an increased risk of implant failures (P = .036
using dependent estimation; P = .004 using independent estimation). The HR increased to
6.6 for patients who had smoked for 45 years. Loosening of prosthetic components were
rare (n=12). No fractures of screws or implants were found.

Higher failure rates for former smokers and a dose-response effect between duration of
smoking and implant failure rates suggested that permanent tissue damage from smoking
may occur in addition to immediate local and systemic effects. The frequency of prosthetic
complications was comparable to other studies.

Screw-type tapered implants placed in a private dental office demonstrated a cumulative
survival rate of 91.8 %. The relative risk of implant failure increased with the duration of

Mundt T, Schwahn C, Hotz W, Biffar R

Long-term survival of Tiolox® implants in a dentist´s office

Poster # 0396 University of Greifswald 2005

The 10-year-survival of 91.8 % from a dentist´s private practice demonstrated positive
results similar to those achieved in university clinics using various implant systems. Mandibular
implants in the anterior region were most successful, while posterior maxillary implants
showed the highest failure rate. Not only current but also former smokers had more implant
failures compared to non-smokers. Higher failure rates even in former smokers and a dose/
response effect between smoking duration and implant failures point to permanent tissue
damage taking place due to smoking, in addition to immediate local and systemic effects of
cigarette compounds. Therefore, dental implants are indicated with restrictions in smokers
who have smoked for many years.

Kappert, HF

Titan als Werkstoff für die zahnärztliche Prothetik und Implantologie

Deutsche Zahnärztliche Zeitschrift 1994 Aug, 49(8): 573-578

Titan hat die bemerkenswerte Eigenschaft, dass es mit einer großen Affinität Sauerstoff
bindet und dadurch in Bruchteilen einer Sekunde eine dünne, aber dichte und beständige
Oxidschicht aufbauen kann. Es wird gezeigt, dass Titan hierdurch eine hohe Korrosionsfestigkeit
bei chemischer und elektrochemischer Beanspruchung aufweist und dass sich
auch die Bioverträglichkeit darauf zurückführen lässt. Andererseits ergeben sich Nachteile
und Schwierigkeiten bei der zahntechnischen Verarbeitung durch Gießen, Aufbrennen von
Keramik und bei den Fügetechniken Löten und Schweißen. Lediglich bei der Kunststoffverblendung
nach Silikatisieren wirkt sich die Sauerstoffaffinität wieder vorteilhaft aus. So ist
Titan optimal als Implantatwerkstoff, problematisch als prothetischer Zahnersatzwerkstoff.
Anhand einer Vielzahl von Untersuchungsergebnissen und Messwerten wird belegt, dass
dennoch Titan als Zahnersatzwerkstoff von der Wurzel bis zur Krone einen festen Platz in
der Zahnheilkunde einnehmen kann.

Siegele D, Hotz W, Willmann G

Calculating Stresses in the Jaw Bone around Threaded Implants

ZZI 1992 September, 8(3): 179-184

Stresses in the jaw around different threaded dental implants were calculated using the
finite element method. This involved, on the one hand, testing the main effect of thread
design on stress distribution in the bone and, on the other hand, testing stresses around
a TIOLOX® implant. The thread geometry of the TIOLOX® implant designed by W. Hotz is
contoured to ensure uniform, favourable stresses in the bone.

Hotz W

The Tiolox® implant system

Zahnärztliche Praxis 1991 July, 42(7): 254-256

Scientifically substantiated findings on the one hand and many years of practical experience
with numerous implant systems on the other hand have led to the development of an
endosteal implant which is suitable in many maxillary and mandibular indications. The
surgical technique is simple and meets the requirements of a universal implant system.

Dentaurum. Quality. Worldwide. Unique.