Poster 144, Sprache: EnglischBethlenfalvy, Eric von/Frech, Jens/Pioch, Thomas/Staehle, Hans Jörg/Dörfer, Christof E.Purpose: To compare the cleaning efficacy of a battery powered toothbrush (Spin Brush classicTM) and a standard flat trim manual toothbrush (ADA reference brush) in a single blind cross over study. Materials and Methods: 76 healthy subjects took part in this study. Subjects were asked to abstain from all oral hygiene procedures for 48 hours. Plaque was scored with the Turesky modification of the Quigley Hein Index. Then the subjects brushed their teeth for one minute with either one or the other brush according to a predetermined randomisation schedule. Immediately after brushing, plaque was scored again. All plaque scoring was done by the same investigator who was blind with respect to the brushes used. Subjects were instructed to continue with their usual oral care routine for 12-14 days. After this period they came back to the study centre having abstained from all oral hygiene for 48 hours prior to the visit. The evaluation sequence was repeated, this time the subjects were brushing with the alternate brush. To compare the cleaning efficacy of the two brushes, the percentage plaque reduction was calculated.
Results: Using the non-parametric Wilcoxon test for paired samples (pTM (pTM (pTM compared to 38.9±14.9% for the manual toothbrush (p=0.047), and for the proximal surfaces 32.7±14.6% and 36.3±13.7%, respectively (p=0.024). It is concluded, that both brushes removed a significant amount of plaque. The Spin Brush classicTM, however, failed to improve the plaque removing efficacy of a standard flat trimmed manual toothbrush. This study was sponsored by Oral-B Laboratories, Boston MA, USA.
Schlagwörter: battery toothbrush, manual toothbrush, plaque index
Poster 145, Sprache: DeutschBürklin, Thomas/Ratka-Krüger, Petra/Schacher, Beate/Böddinghaus, Boris/Hassenrück, Sabine/Eickholz, Peter/Kim, Ti-Sun/Renggli, Heinz H./Schaecken, Matthijs T.DNA probes are commonly used for improvement of periodontal diagnosis. In this present study, two simultaneously collected periodontal plaque samples were analyzed by two commercially available DNA probes (IAI PadoTest 4.5® and microDent®). The aim of this study was to compare the results of these tests and to determine their degree of correspondence.
In the first investigation, samples from 20 sites (10 sites each) were analyzed by each test. The percentage of corresponding sites in which both samples were tested positively are as follows (IAI PadoTest 4·5® / microDent®): A.a. 100%/ 100%, B.f. 70%/ 90%, P.g. 90%/ 100% and T.d. 60%/ 90%.
In a second investigation, a total of 271 plaque samples were analyzed by both tests. The results also displayed a high correspondence between the two tests: A.a. 82,6%, B.f. 76,6%, P.g. 80% and T.d. 67,4%.
Thus it can be concluded that the results of both tests are well corresponding concerning the pathogens A.a., B.f., P.g. and T.d. The results did not show any clear superiority for any one of the tests.
Nevertheless, the results of the second investigation give reason to carefully interpret results from DNA probe tests. Treatment planning should therefor not be based on test results alone, but additionally on good clinical judgement.
Schlagwörter: Parodontitis, DNA-Sonden, Mikrobiologie, Diagnostik
Poster 146, Sprache: EnglischHaessler, Dieter/Khoury, Fouad/Gehrke, Peter/Neugebauer, Jörg/Adam, Josef/Koke, UlrichWhen osseointegrated implants were first introduced, they were only recommended for the restoration of moderately or severely atrophied edentulous jaws. Disregarding anatomical structures standard cylinder implants were used, varying in length only. This compromise often caused fracture of prosthetic components, incessant screw loosening and eventually a failure of the implant. Today's efforts towards attaining esthetic and functional long-term success of implant-supported prostheses focus not only on prosthetic aspects but on preservation or reconstruction of skeletal and soft tissue structures. According to anatomical studies, root-analog implants corresponding in shape, diameter and length to the root geometry of the natural dentition are consistent with the anatomy of the maxilla and mandibula. The earliest possible placement of an anatomically shaped implant prevents the atrophy of alveolar process and maintains gingival height for better soft tissue esthetics.
An anatomic implant diameter is of importance for the:
Functional load distribution
Prosthetic and bio-mechanical stability
Higher degree of implant-to-bone contact
Correct soft tissue adhesion
Reconstruction of an anatomic emergence profile
When small diameter implants are used due to narrow ridge dimension, the finished restoration will be significantly larger than the implant. To achieve normal restorative dimensions the crown must be ridge-lapped which results in limited hygiene possibilities and stress on the implant and abutment screw. Whenever it is possible to match implant diameter to the size of the replaced tooth, a smoother and more natural emergence profile results. Therefore the availability of tooth analog implant diameters for the reconstruction of molars, premolars, canines, lateral ad central incisors expands treatment options and enhances the therapeutic outcome. An ideal implant placement according to anatomic considerations is achievable because of the flared root-analog stepped implant design, without risk of damage of adjacent anatomical structures.
The availability of an implant diameter according to root diameter, and the earliest possible implant placement post extraction are important parameters for a successful esthetic and functional result. Clinical cases will underline the benefits of root-analog wide diameter implants such as: increased prosthetic and bio-mechanical stability, reduced screw stress, higher degree of implant-to-bone contact, taking full advantage of remaining bone under the maxillary sinus in order that surgical procedures can be reduced, improved emergence profile and avoidance of ridge-lap designs.
Schlagwörter: root-analog implants, wide diameter implants, esthetics of implantcrowns, natural emergence profile, soft-tissue management, hygiene access of implants, functional load distribution, biomechanical stability, preservation of soft tissue, implant placement
Poster 147, Sprache: EnglischKneist, Susanne/Borutta, Annerose/Eherler, Dietrich/Chemnitius, Patrick/Merte, Anja/Stößer, LutzThe aim of the study was to investigate those factors that could be correlated with mutans streptococci (MS) transmission and caries decay (dmft) among children aged 30 months; 85 boys and 70 girls were included. A questionnaire concerning the nutrition history and childhood nursing practice was completed by the parents. The caries status of the children was examined, and the salivary MS of the children as well as their mothers (n = 155 pairs) were determined by Dentocult® SM. Two isolates were picked from spatulas from 34 mother-infant-pairs. The pure cultures (n=128) were identified by biochemical tests and by their membrane fatty acid profile (MIDI, Newark USA). Bacteriocine-fingerprinting was performed for all isolates to determine the similarity within each family and among the strains.
65% of the mothers and 24% of the children harboured high salivary MS (scores SM 2 and 3). Furthermore, higher counts could be estimated in 50% of the mothers and in 9% of the children.59% of the strains were bacteriocinogen against S. sanguis, S. oralis, S. gordonii, S. mitis and S. salivarius. 41% of mother-infant-pairs harboured the active strains and, furthermore, half of them harboured identical strains.
The caries decay of the children was registered at a mean dmft of 0.6 ± 2.0. Higher scores of MS correlated significantly with higher caries decay (Spearman's correlation coefficient 0,32712, X2-test p 0.0001). The upper incisors showed significantly more frequent decay (X2-test p 0.001). Furthermore, a positive correlation could be found between high MS counts in children and bottle-feeding at night (X2-test p 0.003). The data suggest that bottle-feeding, especially at night, may support the fidelity of MS transmission from mothers to infants and that bottle-feeding at night may contribute to a higher caries rate.
Schlagwörter: caries prevention, early childhood caries, behaviour of mothers, bottle-feeding, mutans streptococci, bacteriocin-fingerprinting, transmission
Poster 148, Sprache: DeutschKüttner, Christian/Schönweiler, Rainer/Schirdewan, Britta/Dempf, Rupert/Hausamen, Jarg-Erich/Ptok, MartinThere is still a controversy regarding the timing of repair of the deformities associated with cleft lip and palate (CLP). At Hannover Medical School 417 patients underwent primary palatoplasty and veloplasty at 24-30 months of age from 1985 to 1993. This study gives a premilary report of the long-term speech and language outcome of this collective. 30 patients were randomly selected and a retrospective evaluation of data collected from 1985 to 2000 was performed summarizing receptive and expressive speech and language skills. In a prospective evaluation those probands were reexamined (mean 13 years after palatoplasty) and the nasalance was determined with NasalViewTM. The materials used were the vowels /a:/, /e:/, /i:/, /o:/, /u:/, the sentences S1 'Die Schokolade ist sehr lecker' ('This chocolate is tasty') and S2 'Nenne meine Mamma Mimmi' ('Call my mum Mimmi'), and the text passages of LT1 'Nordwind und Sonne' 'Northwind and Sun'), LT2 'Kindergeburtstag' ('A childs birthday party') and LT3 'Der große Gesang' ('A famous song'). As a control-group 20 healthy children of the same age were selected. The median age was 14 years (range from 11 to 19 years). 27 patients (90%) did not feel any handicap, while 3 patients (10%) described little impairment. The mean nasalance for the vowels, for S1 (containing no nasal consonants), for LT2 (with many nasal sounds) and for LT3 was significantally higher than the mean nasalance of the control-group. For S2 and for LT1 there were no differances to the control. The clinical implications of these results were discussed and it is suggested that an earlier closure of the palate will lead to better functional results in CLP patients.
Schlagwörter: nasalance, nasality, cleft lip and palate, velopharyngeal incompetence, velopharyngeal insufficiency
Poster 149, Sprache: EnglischKüttner, Christian/Hausamen, Jarg-Erich/Dempf, Rupert/Brachvogel, PeterThe choice of surgical approach to tumors of the cranial base in children is determined by strict criteria. These include optimal visibility for the surgeon, a minimum possible impairment of facial skull growth and the preservation of motor and sensory nerve integrity. From 1993 to 1996, 3 children (6 years, 22 month, 8 month) were operated for cranial base tumors via a lateral transmandibular approach. In all these patients preauricular incision with temporal and submandibular extention was performed. After preparation of the mandible an osteotomy was made above the mandibular foramen and the capitulum could be temporarily exarticulated. Now a wide access to the cranial base was provided and the tumors could be resected. It was possible to follow-up two of these children, observing their further development until the present day. Considering the severity of conditions, the patients achieved good results. For tumor surgery the transmandibular approach to the cranial base. Growth impairment of the mandible can be corrected successfully by distraction osteogenesis technique.
Schlagwörter: transmandibulärer Zugang, Schädelbasis, Kleinkind, lateral transmandibular approach, skull base surgery, children
Poster 150, Sprache: DeutschLeitner, Christoph/Zanger, Philipp/Hoffmann, Jürgen/Kaiserling, Edwin/Reinert, SiegmarA case of a 68-year-old man is described who was referred to our department for further treatment of a malignant hemangiopericytoma of the left maxillary sinus. The referral diagnosis was made through an incisional biopsy. After angiographic verification of a highly vascularized tumour, embolisation of the left maxillary artery was performed. Further surgical treatment consisted of a hemimaxillectomy, partial resection of the orbital floor and removal of the ethmoidal cells. The histopathological examination of the removed tumour revealed a cellular infiltrate of spindle-shaped cells in a fibromyxoid stroma containing inflammatory cells consisting of lymphocytes, plasma cells and macrophages. The spindle-shaped cells expressed vimentin and a-smooth muscle actin positive immunophenotypes. Considering the histological features the initial diagnosis of a malignant hemangiopericytoma was withdrawn and the diagnosis of an inflammatory myofibroblastic tumour was made. In view of the changed diagnosis the initially planned exenteration of the left orbit did not have to be performed. This case report shows that an incisional biopsy remains problematic with regard to an accurate diagnosis of spindle-celled soft tissue tumours with overlapping morphological features and different clinical behaviour. In order to avoid unnecessary impairment of quality of life the treatment should not be performed too aggressively until the definitive histological diagnosis has been made on the removed tumour.
Schlagwörter: spindle-celled soft tissue tumour, malignant hemangiopericytoma, inflammatory myofibroblastic tumour, maxillary sinus
Poster 151, Sprache: DeutschMolzberger, Myriam/Janko, Steffanie/Weigl, Paul/Bauer, Axel/Lauer, Hans-ChristophThesis: Aim of this study was to compare newly developed and conventional retention systems by objective measurements of the clinical adhesion force of prostheses.
Material and methods: The adhesion force was measured for each prosthesis with a specially developed device. Therefore the prosthesis was connected with a plate at the occlusal surface. A centered fastened loop served as a loose coupling with a dynamometer-box (Fa. Typ U2A, Hottinger Baldwin Measurements, Marlborough, USA), which avoids the prosthesis to stand on edge during the pull-off phase. The device was calibrated prior to each series of measurements. 10 consecutive measurements for each prosthesis were performed in a prospective clinical trial. Mean values were calculated and defined as adhesion force.
Test group: 8 metal-free tapered crown prostheses (primary crown: ceramic, Empressâ 2; frame: fibre composite, Vectrisâ: Fa. Ivoclar Schaan-Liechtenstein) on 28 abutments (6 teeth, 22 implants).
Control group: 12 conventional tapered crown prostheses on 58 abutments (24 teeth, 34 implants).
Results: The relative standard deviation of the 10 single-measurements was 3,9 % on average. The average adhesion force of the test group (4,8N±1,7N) did not significantly differ from the control group (5,1N±2,9N); (Anova, p
Poster 152, Sprache: EnglischNeugebauer, Jörg/Gehrke, Peter/Apfel, Sören/Steveling, Helmut G./Haßfeld, StefanImmediate loading has become one of the most interesting topics in clinical research, since it can result in increased patient acceptance and reduce treatment time and management problems. Favourable results with different clinical procedures are shown in case presentations. All authors claim to gain a maximum of primary stability with the surgical and prosthetic procedures applied.The aim of this in vitro study was to evaluate the precision of osteotomies by using the same drills in various bone qualities and at different speeds. In addition, the insertion torque as a factor for primary stability was determined by various thread designs.
Self tapping threads require sufficient space for the prepared bone. Consequently, the thread design determines the size of the final osteotomy. The precision of the implant sites varies according to bone quality and the drilling speed. While better results are achieved by preparing bone of density type I with 800 rpm, the best results were obtained by preparing bone of density type IV with a higher speed of 1500 rpm. In cortical bone type I, highest primary stability was achieved with a precut thread and a low thread height of 0.1 or 0.2 mm. In bone of type III or I, 0.3 mm to 0.5 mm self-tapping threads provided the best results. Due to the difficult evaluation of the exact bone quality between type II and type III, a combination of the two thread heights seems to be optimal to ensure sufficient primary stability.
Schlagwörter: immediate loading, implant design, thread design, insertion torque, self-tapping implant design, bone quality, primary stability
Poster 153, Sprache: SpanischSobarzo-Navarro, Victor/Braun, AndreasEndodontic treatment of permanent teeth with open apexes using calcium hydroxide and mineral trioxide aggregate should be compared.
Medical histories of all patients were noncontributory. After clinical and radiographic investigation the pulp chamber was exposed after rubber dam placement. The working length of the canal was determined with a conventional or digital radiograph. The canal was instrumented with hand files. Sodium hypochlorite (2 per cent) was used as an irrigant. Method 1: the root canals were carefully dried and filled with a calcium hydroxide paste (Calcicur, Voco, Cuxhaven, Germany). The calcium hydroxide dressings were changed every two months until a calcific barrier formed at the apex after an average period of 16 months. Method 2: the calcium hydroxide dressing was changed twice in intervals of 15 days. Then mineral trioxide aggregate was placed for apical barrier formation. Six hours later, the canal was obturated. All canals were obturated by using a warm gutta-percha technique (ObturaTM, Obtura Corporation, Texceed, USA) and a sealer (SealapexTM, Kerr, Karlsruhe, Germany). Using a calcium hydroxide paste in combination with mineral trioxide aggregate for apical barrier formation it is possible to reduce the treatment time for about 87.5 per cent in comparison to the exclusive use of a calcium hydroxide dressing. The application of mineral trioxide aggregate within the apical part of the root canal was unproblematical.
Reducing the number of appointments, it is possible to reduce the stress factor of young patients and their parents. The use of digital radiography also contributes to reduce the fear of parents regarding high radiation dosis.
Schlagwörter: apical barrier formation, calcium hydroxide, mineral trioxide aggregate
Poster 154, Sprache: EnglischHenning, Thorsten/Heinrich-Weltzien, Roswitha/Röhrig, Bernd/Kehrer, Uwe/Stößer, LutzThis study was aimed to investigate the correlation between the protein composition of human mixed saliva from participants of a caries risk assessment study. The participating schoolchildren exhibited a caries incidence from 0.34 to 0.71 while ageing from 8 to 10 years.
Three unstimulated mixed saliva samples of 111 subjects were collected during 2 years and 50 µl were analysed by reversed phase HPLC (RPLC) (Hewlett-Packard ChemStation LC 1100, Zorbax 300 SB-C8 column (4.6 x 150 mm, 3.5 micron) at 35 °C, UV detection at 215 nm).
The protein content of nine fractions was determined using bovine serum albumin (BSA) as an internal standard. A cluster analysis (Ward method) with the protein contents of the nine protein fractions was performed, which allowed a separation of the subjects into two distinct cluster groups, distinguished to the two- or three-fold of the protein content for one group (Tab. 2). The number of test persons assigned to cluster 2 decreased dramatically with increasing age of children.
Schlagwörter: saliva, protein, caries risk, hplc, cluster analysis
Poster 155, Sprache: DeutschDietrich, Michael/Arnold, Wolfgang H./Braasch, Volker/Grimm, Wolf-DieterIntroduction: The surface characteristics of Ti-Implants have a direct influence on the proliferation and differentiation of the subepithelial-gingival as well as the periodontal-enossal fibroblasts. Therefore the structure of this surface influences the quality of the mucosal interface and the osseointegration of the implant.
The aim of this study is to review the ultrastructure and chemical composition of Ti-Implant systems.
Material and methods: The mucosal and enossal compartments of 10 Ti-Implants with different surface characteristics (acid-etched, machined screw, TPS-coated) were examined by a REM in a 2000x magnification. EDX analyses were made to evaluate the chemical composition. The roughness and hardness of the surface was measured in comparable regions of the mucosal and enossal compartment. Grade 1 and 4 Titanium is used in all implant systems.
Results: The ultrastructure of the mucosal interface shows the characteristic turning pattern with depths up to 15µm. The surfaces show different fracturing of metal chips and pitting attack. From the REM analyses it appears as if the diameter of the pits varies in the range of 0,1µm to 10µm. That suggests that the light particles are formed during turning and are loosely bond to the surface. The surface of the enossal regions show different patterns depending on the technology of manufacture. The surface of the mucosal regions show a roughness of 0,47-2,88µm, the enossal regions from 5,8 to 1,43µm. The hardness of the tested Ti-implant systems was measured between 1674 und 23330 N/mm2. The EDX analysis shows, that the chemical composition of the enossal spots was Ti: 90,9-100,0%; Al:8,90%; Cl 8,57%. At the mucosal surfaces there was mainly Titanium detected.
Conclusion: There must be demands for the transmucosal surface structure to provide the epithelial and mucosal attachement.
Schlagwörter: dental implants, surface pattern, ultrastructure, chemical composition