Poster 230, Sprache: EnglischKleinheinz, Johannes/Faloppa, Ana Christina Breithaupt/Jayaraman, Mythili/Wiesmann, Hans-Peter/Joos, UlrichSuccessful clinical application of compound materials should involve detailed investigations on interaction between material and tissue. A desirable feature of scaffolds is the ability to support new blood vessel growth. With the present investigation, we examined the behaviour of endothelial cells on a type-I collagen matrix using histological and immunohistological methods. The endothelial cells were isolated from human umbilical cord veins and were identified as endothelial cells by staining with a panel of endothelial cell specific antibodies. After two passages cells were seeded in standard density on a type-I collagen matrix. After 1 and 7 days attachment, proliferation, differentiation and adhesion of the cells were analysed with specific markers. We could demonstrate that type-I collagen is an ideal matrix for endothelial cells concerning growth and maturation and that it could be used as a carrier matrix for different cell types during tissue engineering.
Schlagwörter: endothelial cells, collagen, adhesion, proliferation, differentiation
Poster 231, Sprache: EnglischBizhang, Mozhgan/Ley, Matthias/Zimmer, Stefan31 children were examined in this pilot study. They were between 11-13 years old and had at least one permanent second molar present. Status of oral hygiene (TURESKY modification of the QUIGLEY and HEIN plaque index, QHI, and Approximal plaque index, API), the gingivitis index (Papillary bleeding index, PBI), Status of caries (DMFS/dmfs), and values of ClinproTM Cario Diagnosis were recorded. Data analysis was accomplished using Kappa test (SPSS 10.0). We did not observe any good correlation between ClinproTM Cario Diagnosis and Caries lesions, nor between ClinproTM Cario Diagnosis and oral hygiene indices. These results suggest that ClinproTM Cario Diagnosis was not suitable for indication of caries and that it was different from oral hygiene indices.The study was supported by 3M ESPE.
Schlagwörter: QHI, API, lactic acid, caries risk, oral hygiene
Poster 232, Sprache: EnglischBekes, Katrin/Gernhardt, Christian Ralf/Schaller, Hans-Günter/Maurer, Peter/Schubert, JohannesObjectives: The study was performed to compare tensile bond strength obtained between composite and bone and between bone and bone using two different adhesive systems (Clearfil New Bond and Histoacryl) in vitro. Methods: Six mandibles of freshly sacrificed pigs were used to prepare ten specimens each using trephane burs under constant water cooling. Sixty bone specimens with a total thickness of 4.0 mm (± 0.5 mm) and a cortical layer of 1.5 mm (± 0.2 mm) were obtained under standardized conditions. Each ten specimens were assigned to four experimental groups (Group A: Clearfil New Bond (bone-composite); Group B: Clearfil New Bond (bone-bone); Group C: Histoacryl (bone-composite); Group D: Histoacryl (bone-bone)). Tensile bond strength of the above mentioned adhesive agents was measured 15 minutes after application and additional after light curing of the composite material (Tetric Ceram, colour A2; Group A,C) using an universal testing machine. Results: Following tensile bond strength were evaluated (mean value and standard deviation, printed in MPa): Group A: 8.00 (± 1.36); Group B: 6.39 (± 2.05); Group C: 5.22 (± 2.01); Group D: 1.95 (± 0.49). Statistical analysis showed a significant influence of the used adhesive system and the modality on tensile bond strength (p Conclusions: Regarding the limitations of an in vitro investigation, it can be concluded that adhesive systems might be a useful alternative in bone bonding. The use of dentin adhesives seemed to produce higher bond strength to bone compared to the cyanoacrylate adhesive.
Schlagwörter: bond strength, adhesive systems
Poster 233, Sprache: EnglischGernhardt, Christian Ralf/Hicyilmaz, Serkan/Schaller, Hans-GünterThe aim of the present investigation was to evaluate the influence of four different stress simulations on tensile bond strength of a single-component dentin adhesive (Excite). Therefore sixty caries-free third molars, stored in saline for a maximum of seven days after extraction, were used. All teeth were prepared in a special manner allowing the simulation of the dentin perfusion. Dentin specimen with a thickness of 3.5 mm were obtained under standardized conditions. The specimen were randomly assigned to four experimental groups of 15 each. Tensile bond strength after four different stress modalities (group A: max. load without cycles; group B: max. load after increasing cycles; group C: max. load after 100 constant cycles; group D: max. load after 200 constant cycles) was evaluated using an universal testing machine 15 minutes after application and light curing of the composite material (Tetric Ceram, colour A2). Following tensile bond strength were evaluated in MPa:Group A: 5.25 (± 0.87), Group B: 4.01 (± 1.10), Group C 5.80 (± 2.11), Group D: 8.23 (± 1.24). Statistical analysis showed a significant influence of the different stress modifications on tensile bond strength (p
Schlagwörter: dentin, dentin bonding, tensile bond strength, dentin bonding agent
Poster 234, Sprache: EnglischGernhardt, Christian Ralf/Stache, Carola/Kielbassa, Andrej M./Schaller, Hans-GünterThe aim of the present investigation was to evaluate the caries-protective effect of two dentin adhesives on development of root caries after tooth-brushing abrasion in vitro. The root surfaces of fifty freshly extracted human molars were cleaned using polishing discs, thereby removing the cementum. The teeth were then coated with acid-resistant nail varnish, exposing two retangular windows of 6mm2 each. One window served as control, while the other window was tooth-brushed for different brushing cycles (group A1/2: 400x, group B1/2: 800x, group C1/2: 1200x, group D1/2: 1600x, group E1/2: 2000x) after dentin adhesive application. Respectively, 25 specimen were treated with one of the two dentin adhesives (1: Optibond Solo; 2: Prime & Bond NT) as recommended by the manufacturer. After brushing all specimen were demineralized with acidified gel (HEC, pH 4.8, 37 °C). From each specimen, three dentinal slabs were cut. The lesion depth was determined using a polarized light microscope. All unbrushed control specimen showed no lesions. In case of Optibond Solo lesions could be observed after 800 brushing cycles (A1: 0µm; B1: 31µm; C1: 12µm; D1: 13µm; E1: 37µm). The brushed specimen treated with Prime & Bond NT exhibited following lesion depths: A2: 0µm; B2: 36µm; C2: 55µm; D2: 52µm; E2: 57µm. Pairwise comparison showed significant differences between the two materials in group C, D, and E (ANOVA; p
Schlagwörter: dentin, dentin adhesive, root caries, demineralization, abrasion
Poster 235, Sprache: EnglischStratul, Stefan-Ioan/Sculean, AntonAn oily Calcium Hydroxide suspension has been shown to enhance healing of various types of bone defects. The aim of this study was to evaluate de effect of a combination of an oily Calcium Hydroxide suspension (Osteoinductal®, Osteoinductal GmbH, Muenchen, Germany) with α-TCP (BioBase® α -pore, Biovision GmbH, Ilmenau, Germany) vs. α -TCP alone in the treatment of one- and two-wall intrabony pockets. 12 patients with moderate to severe chronic periodontitis and displaying a total of 26 intrabony defects were included in the study. The intrabony defects were randomly treated with either α-TCP alone or with the combination of α-TCP and Osteoinductal®. The following parameters were evaluated at baseline and six months after surgery: probing depth (PD), gingival recession (GR) and clinical attachment level (CAL). Post surgical care included administration of antibiotics (Amoxycillin) 3x500mg daily for one week and 0.2% chlorhexidine rinses twice daily for two weeks. At six months after surgery the results revealed in the combination group a mean CAL change from 8.07±1.44 mm to 4.21±1.81 mm (p
Schlagwörter: periodontal regeneration, oily calcium hydroxide suspension, alpha-TCP
Poster 236, Sprache: EnglischStratul, Stefan-Ioan/Rusu, Darian/Enache, Alexandra/Ogodescu, Alexandru/Jianu, Rodica/Popescu, Mugur GeorgeBone regeneration using bone substitutes and/or bone promoters have become a widely considered adjunct to surgical endodontic therapy. Numerous bone grafting materials claimed over the years to promote osseous healing of lesions of endodontic origin.
An oily Calcium Hydroxide suspension (Osteoinductal®, Osteoinductal GmbH, Muenchen, Germany), clinically proven to reduce post-extraction pain, inflammation and bleeding, has been used in this preliminary controlled study to promote bone healing in surgically treated periapical lesions.
16 lesions with diameters varying between 7-20 mm were randomly treated either with apicoectomy, curettage and Osteoinductal® (treatment group), or with apicoectomy and curettage alone (control group). Standardized radiographs were taken before and two months after the surgery. The Osteoinductal® group displayed an excellent clinical healing. Evaluation was made on the radiographs at two months by using a computer-assisted densitometric method. Statistical analysis used the Mann-Whitney non-parametric test.
Relative density between individual standard areas of sound bone and the periapical areas of surgically treated teeth varied between 50% and 108% within the Osteoinductal® group, with a mean value of 79 ± 19,7%, and between 64% and115% with a mean value of 89 ± 18,7% within the control group.
The results show that the oily Calcium hydroxide suspension did not improve the relative bone density of surgically treated periapical lesions at two months, but the difference between the groups was not statistically significant. Results also indicate the limits of the densitometric analysis in groups with large dispersion of the values, and, subsequently, a strong dependence of the analysis on the initial size of the defect and on the number of cases.
Schlagwörter: periapical healing, densitometry, oily calcium hydroxide suspension
Poster 237, Sprache: EnglischStratul, Stefan-Ioan/Benta, AncaThis is a case report of a 43-y.o. female patient who suffered a home accident, which resulted in the incomplete alveolar fracture of regio 23-25, labial luxation and displacement of 23. Primary trauma care missed the dental diagnosis and delayed with 48 hrs the report of the patient to the dentist, that referred her immediately to the endodontist. On examination, 23 labially out of alignment and severe pain at slightest touch were noticed. Standardized radiographs revealed a very thin, artifact-like horizontal fracture of the mid third root of 23. Many treatment options, varying from avulsion to transfixation of 23 were taken into consideration. As the endodontist' suggestion was the extreme conservative treatment attempt, the incomplete alveolar fracture was reduced under anesthesia, the root canal treatment with Ni-Ti rotary instruments (ProTaper - Dentsply-Maillefer) was performed and Root-MTA was placed into the canal as permanent dressing. 23 was splinted in correct position. There was no post-treatment simptomatology. At 4 months, the tooth remains asymptomatic with no mobility. Radiographic examination reveals a blurry profile of the fracture site, with very slight periradicular modifications. The case report suggests that 1) deep horizontal root fracture combined with teeth displacement can be successfully treated 2) the immediate intervention of the practitioner with the rationale application of the sequence replacement-rotary root canal treatment-Root-MTA-splinting spectacularly improves the conservative outcome of similar cases.
Schlagwörter: root fracture, displacement, RootMTA
Poster 238, Sprache: EnglischZipprich, Holger/Weigl, Paul/Fischbach-Sedlatschek, Silke/Lauer, Hans-ChristophIntroduction and Objectives: Implant-abutment connections (IAV) show in vivo loosenings (L) and fractures (F) probably as a result of preceding micro movements (MM). The failure modes and their causes shall be evaluated. Material and method: 9 IAV types ∅ = (4-5 mm, n=8) were exposed to 106 cyclic loadings each, (100 N, 90° to the implant axis, at a distance of 8 mm from the IAV). In addition to this, the actual force on the IAV per cycle was measured. A computer-assisted sound analysis was used for the online detection of MM, L and F. For the analysis of L and F X-ray, REM and light microscopic photos were used. At the IAVs which remained intact, the was measured as well. (the moment of solve of the abutment was intended.) Results: Two IAV types didn't show any failure modes, but wear traces at the connection areas as can be proved. By one IAV type, a MM was detected preceding a L. Fractures at the connection screws and the abutments appeared at six IAV types. Only at one IAV type implant fractures occured. At none conical IAV types the failure frequency correlates with decreasing implant-diameter. However, at conical IAVs there is no correlation between failure frequency and implant-diameter. Summary: The occurrence of wear traces or failure modes (MM, L, F) shows, that all of the IAVs, with regard to horizontal encumbrances, feature constructions-conditioned weaknesses, which, in case of a long -term osseointegration of implants, could lead to a clinical component-failure (constructional element-failure), particularly in case of single tooth implant restorations placed in the lateral region.
Schlagwörter: implant, abutment, failure mode, screw, fracture, loosening, Implantat, Aufbau, Pfosten, Versagensmodi, Schraube, Fraktur, Lockerung
Poster 239, Sprache: EnglischStricker, Andres/Schramm, Alexander/Bormann, Kai-Hendrik/Schmelzeisen, RainerOrientation of the distraction direction has to be defiened prior to the first movement. Mistakes in the way of angulation are very difficult to correct.Presenting the new bidirectional distraction device it can be demonstrated the way and the opportunity to correct misangulation during the distraction process. Clinical short- term results demonstrate that simultaneous vertical and horizontal bone augmentation is possible by this new bi-directional distraction device.
Schlagwörter: distraction, implant, bone augmentation