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Purpose: The aim of this prospective randomized controlled trial was to evaluate the influence of clinical baseline characteristics on the survival of 2 post systems., Materials and Methods: One hundred patients needing a post were included. Half the patients received a glass fiber-reinforced post (FRP), and the other half received metal screw posts (MSP). The posts were assigned randomly. In addition to demographic data, the following parameters were recorded: type of tooth (incisor/canine versus molar/premolar), length of the post in relation to root length (percentage), extent of coronal tooth destruction (percentage), ferrule height (in millimeters), type of restoration (fixed or removable partial denture), and presence of antagonistic contacts (yes/no). After at least 1 year (mean: 13.84 months), the patients were recalled. Statistical analysis was performed using the log-rank test and Cox regression analysis., Results: The survival rate of FRPs was 93.5%. In the MSP group, the survival rate was significantly lower (75.6%; log-rank test, P = .049). Additionally, the metal posts were associated with more unfavorable complications, for example, root fracture. The type of the tooth and the degree of coronal tooth destruction influenced the survival of MSPs, whereas no influence of these variables could be seen for FRPs., Conclusion: FRPs are superior to MSPs with respect to short-term clinical performance. Especially for MSPs, clinical survival depends on several variables.

Objectives: The purpose of this randomized clinical trial was to evaluate the clinical wear behavior of posterior, metal-free polymer crowns, with and without a glass-fiber framework, and to compare it with that of metal-ceramic crowns., Methods: Eighty single crowns manufactured from a newly designed polymer composite were set in posterior teeth. Half of these received a glass-fiber framework (group 1) whereas half were prepared without framework stabilization (group 2). All polymer crowns were adhesively luted with resin cement. As the control group, 40 conventional metal-ceramic crowns were inserted with hybrid cement. Wear was measured, by use of gypsum replicas, at baseline and after 12 months, by use of a 3D laser scanner. Statistical analysis was performed using mixed-effects regression model analyses., Results: The mean total wear of posterior single crowns was -8.1 microm (+/-9.7 microm) in group 1, -7.0 microm (+/-9.1 microm) in group 2, and -3.4 microm (+/-6.3 microm) in the control group. Statistical analysis revealed wear behavior was significantly different from the control group for group 1 (p=0.014) and group 2 (p<0.01). No significant difference was detected between groups 1 and 2. Age, gender, and opposing teeth had no significant effect on wear behavior., Conclusions: Within a 12-month observation period mean total wear of posterior polymer crowns with and without a glass-fiber framework was significantly greater than for metal-ceramic crowns. The selection of restorative materials should be based on knowledge of clinical wear in order to preserve occlusal stability.

Objectives: The aim of this study was to evaluate the clinical performance of posterior, metal-free polymer crowns with and without a glass-fiber framework, in comparison to metal-ceramic crowns., Methods: After randomisation, 80 single crowns, manufactured from a newly designed polymer composite, were set in posterior teeth. Half of these received a glass-fiber framework, while half were prepared without any framework stabilisation. All polymer crowns were adhesively luted with resin cement. As the control group, 40 conventional metal-ceramic crowns were inserted with hybrid cement. Documentation included failures and other complications, as well as gingival/plaque status and aesthetic performance., Results: During the 12-month observation period, eight polymer crowns and three metal-ceramic crowns showed clinically relevant complications. The most frequent complications were root canal treatments (n=4) and decementation (n=4) of the crowns. A total of two crowns (one polymer crown with fiber network and one crown of the control group) had to be replaced. After 12 months, polymer crowns with glass-fiber framework exhibited significantly higher plaque accumulation (p=0.005) and gingival index (p=0.04) than metal-ceramic crowns, while no significant differences could be demonstrated for polymer crowns without fiber reinforcement. Postoperative sensibility and aesthetic performance did not differ significantly between the groups., Conclusions: Within a 12-month observation period, posterior polymer crowns with and without glass-fiber framework demonstrated acceptable stability and aesthetic performance. Polymer crowns with fiber framework showed significant higher plaque accumulation and gingival index than metal-ceramic crowns.

Purpose: The aim of this study was to investigate the ability of clinical and magnetic resonance imaging (MRI) diagnoses to predict pain in the temporomandibular joint (TMJ)., Materials and Methods: One hundred forty-nine patients were examined by 2 calibrated examiners in strict accordance with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). All patients who presented with a defined clinical RDC/TMD diagnosis were included and underwent bilateral coronal and sagittal MRI of the TMJ. Two raters blinded to the clinical diagnosis interpreted the MRI scans for TMJ pathology. The results were tested against the clinical diagnosis according to the RDC/TMD, including pain-related disability and psychosocial status, for associations to TMJ arthralgia using logistic regression analysis (GENMOD procedure, P < .05)., Results: MRI-depicted anatomic changes, such as joint effusions, disc displacement, and osteoarthrosis, were not significantly correlated with the presence of pain in the TMJ. However, a significant relationship between pain on palpation of the masseter muscle origin (P = .0050) and psychosocial factors (P = .0452) and pain in the TMJ was demonstrated., Conclusions: Pain in the TMJ caused by the anatomic proximity of the muscle masseter origin and the lateral TMJ pole and the possible existence of trigger points in the musculature may lead to a false-positive or a false-negative diagnosis of arthralgia. Additionally, clinicians must consider the psychosocial aspects of pain in ideal treatment planning.

Objectives: The objective of this study was to examine the two-body wear resistance of nine different resin denture teeth and one experimental material., Methods: The two-body wear test was performed in a chewing simulator with an antagonistic Al(2)O(3) ball under an axial load of 40 N for 100,000 cycles. In each test series, an enamel sample was included as a reference. The wear was determined with an optical 3D surface profilometer. For statistical evaluation, SPSS for Windows was used., Results: The samples of Artiplus (18.7-SD 21.0) and e-Ha (21.2-SD 15.1) showed the lowest volumetric wear (in mm(3)x10(-3)) after 100,000 cycles. The difference from the other materials tested, except NC Veracia Posterior, was statistically significant (p=0.001-0.037). SR-Postaris-DCL (55.0-SD 6.8), SR-Orthosit-PE (61.1-SD 12.4) and Vitapan (72.1-SD 15.9) exhibited medium-sized wear values with low dispersion, whereas Orthognat (80.1-SD 31.6), Premium 8 (84.6-SD 31.4), NC Veracia Posterior (87.0-SD 52.7), SR-Orthotyp-PE (114.6-SD 28.0) and Trubyte Portrait (123.0-SD 45.6) showed high wear values with great variations. Statistically provable differences were found between SR-Orthotyp-PE and SR-Postaris-DCL (p=0.019) and also between SR-Orthotyp-PE and SR-Orthosit-PE (p=0.031). For enamel, a medium-sized wear value of 66.1-SD 76.8 was determined., Significance: The denture teeth examined showed differences in two-body wear resistance. The wear values determined were in some cases higher and in others lower than those of natural enamel. A definite connection between the wear resistance and the chemical composition of the materials could not be found in this investigation.

Objective: The aim of this study was to investigate the influence of the age of the subject on inter-examiner reliability of the clinical signs of temporomandibular disorder (TMD)., Methods: Forty-three elderly (ES) and 44 younger adults (YS) were selected. The female/male distribution was almost the same in the two groups. All participants underwent clinical examination according to the Research Diagnostic Criteria for TMD, performed successively by two clinicians., Results: For metric measurements - with the exception of unassisted opening - the ES gave a significantly lower range of motion with both examiners and significantly worse percentage agreement between the examiners. A remarkable inter-examiner disagreement in the elderly was found with laterotrusion and protrusion movements. The prevalence of joint sounds was rated inconsistently by the examiners. The reliability of detection was not different in the two groups. The prevalence of tender muscle sites was also inconsistent. The overall percentage agreement for subjects with at least one tender muscle point was not age dependent. Because of the very low prevalence in ES, further statistical assessment of reliability is not possible., Conclusions: The age-dependent lower range of motion and the inferior reliability of metric measurements in the elderly could lead to wrong diagnoses. The reliability of detecting joint sounds and tender muscles was not age dependent within the limitations of the study.

Objective: The aim of this study was to investigate factors associated with the oral health-related quality of life (OHRQoL) of institutionalized elderly in Germany., Material and Methods: One-hundred-and-fifty-eight subjects from old people's homes were selected (mean 82.8 years). OHRQoL was measured using the Oral Health Impact Profile (OHIP). Denture characteristics (kind and age of denture, retention of removable denture, number of teeth in static occlusion) and general issues (age, gender, education level, and general pain status) were assessed. All factors were subjected to bivariate testing for their effects on the OHIP summary score (OHIP-SC) and to multivariate testing in subjects with removable dentures (n = 128); a linear regression model with backward elimination was used, with OHIP-SC as the dependent variable., Results: In the context of other studies, a median OHIP-SC of 29 indicated highly impaired OHRQoL. According to the bivariate analysis, retention, age of denture, number of teeth in static occlusion, general pain status, and education all exhibited significant influence on OHIP-SC. In the final linear regression model, general pain status, education level, and retention of denture remained at a statistically significant level. The model explained 34% (R2 = 0.34) of the variance of the OHIP-SC. The kind of denture had no significant impact on OHIP-SC., Conclusions: In contrast to other groups, the kind of denture exhibited little impact on OHIP-SC for this highly specific collective. However, there were functional aspects of dentures which seemed to be important. Non-dental factors had a striking effect on OHRQoL.

Aims: To determine whether there is a difference in terms of reliability between experienced examiners and inexperienced examiners in the measurement of signs of temporomandibular disorders (TMD)., Methods: A total of 27 patients seen for treatment of TMD were rated blindly and in random sequence by 2 experienced and 2 inexperienced examiners. The examiners participated in a 4-hour calibration session on the day preceding the reliability study. Both experienced and inexperienced examiners participated in the calibration session to reduce the effect of examiner subjectivity and allow the study focus to be on the effect of experience. The rating followed the Research Diagnostic Criteria for Temporomandibular Disorders and included mandibular movements, joint sounds, and digital palpation of muscles and joints. Intraclass correlation coefficients and kappa statistics were calculated to estimate interrater reliability. The Wilcoxon signed rank test was performed to test for differences between experienced and inexperienced examiners' results, and the Friedman test was used for differences between all 6 examiner combinations., Results: Excellent overall reliability was found for vertical mandibular motions, acceptable reliability was found for the summed muscle palpation pain sites, and moderate to poor reliability was found for excursive movements, joint sounds, and single muscle palpation pain sites. No significant differences in the measurement results could be found between the experienced examiners and the inexperienced examiners., Conclusion: Examiner calibration rather than professional experience seems to be the most important factor for reliable measurement of TMD symptoms.

Aims: The aim of this in vitro study was to evaluate the fracture load of zircon frames veneered with a polymer glass holding box inlay-retained fixed partial dentures (FPDs). The influence of the position of the frame and the span length was tested. Additionally, the fracture load values of zircon frames veneered with a press ceramic were evaluated., Material and Methods: Box inlay cavities were prepared on mandibular molars and premolars. Forty-eight FPDs were manufactured using industrially prefabricated zircon frames veneered with the polymer glass Artglass. Sixteen FPDs received individually manufactured CAD/CAM zircon frames veneered with a press ceramic. All FPDs underwent thermal cycling and mechanical loading (ML). The load to fracture was measured and fracture sites were evaluated., Results: Four polymer veneered FPDs showed fractures in the veneering material after ML. The mean fracture resistance ranged from 531 N to 727 N. No significant influence of frame localization could be observed. Significantly greater fracture resistance values were found in the ceramic veneered FPDs (1276 N to 1413 N). There was no significant effect of span length in the polymer veneered group or in the all-ceramic group, with the exception of a significant peak in fracture load value for intermediate span lengths in the polymer group with a localized occlusal zircon frame., Conclusions: Polymer veneered FPDs with Y-TZP frames showed acceptable fracture resistance values, but they cannot yet be unreservedly recommended for clinical use. Fracture values for CAD/CAM manufactured Y-TZP frames combined with a press ceramic deserve further clinical investigation.

Purpose: The aim of this study was to describe the oral health related quality of life (OHRQoL) of institutionalized elderly., Material: 159 elderly were randomly selected for this, study ranging in age from 61 to 98 (mean age 82.8; 19.1% male, 80.9% female). For measuring the OHRQoL the Oral Health Impact Profile (OHIP) was used. Additionally, a dental status was evaluated., Results: 15% of the subjects had only natural teeth or fixed dentures, 80% removable dentures and 15% no dentures at all. OHIP-mean reached 33+/-25 points, between 0 and 112. The subcategory "functional limitation" showed the highest impairment (6.3%). The items with the highest impairment on OHRQoL in the different subcategories were: dentures not fitting properly, uncomfortable dentures, self-conscious due to teeth, avoid eating some foods, felt depressed, avoid going out and general health worsened., Conclusions: The OHIP summary score represents an overview of OHRQoL and answers detailed questions with the help of the single items. In institutionalized elderly many items showed impairment, especially in items concerning the prosthetic restorations. This demonstrates the need for dental aftercare and not only dental interventions for acute pain. Establishing aftercare and prophylaxis could increase the OHRQoL and subsequently the overall well-being.

Purpose: The objective of this study was to investigate whether a systematically arranged shade guide system (Vita 3D-Master) allows clinicians to achieve a better shade match of a restoration, as compared to a conventional shade guide with a design based on empirical values (Vita Classical)., Materials and Methods: Fifty-nine restorations in 42 patients being treated by student clinicians were assessed. Using 1 of the 2 shade systems assigned randomly, each student independently determined the tooth shade. With the aid of a visual rating scale, the accuracy of the shade match of the finished restoration was assessed., Results: All restorations whose shades had been determined with the 3D-Master could be placed without any further shade corrections. In contrast, almost 17% of restorations determined with the conventional system required subsequent shade modifications. The match of the shades selected with the 3D-Master was judged significantly better by the clinicians., Conclusion: Within the limitations of the study, clinicians with less clinical experience who use a system that guides them through the shade-taking procedure in a relatively systematic manner will be more successful in selecting the correct tooth shade and in avoiding shade corrections. Clinical assessment of the restoration shades showed significant differences between the shade guide with a systematic design and that based on empirical values.

Purpose: To assess the normal position of the temporomandibular joint (TMJ) disk relative to the condyle by using coronal magnetic resonance (MR) imaging in asymptomatic volunteers., Materials and Methods: This study was approved by the review committee for human research, and all subjects signed an informed consent form. Thirty symptom-free volunteers without histories of TMJ disorders underwent standardized clinical examinations. Afterward, bilateral sagittal oblique and coronal oblique MR images were acquired with the patient's mouth opened and closed. The coronal oblique opened- and closed-mouth images were analyzed by using computer software. The medial and lateral edges of both the TMJ disk and the condyle were marked for these imaging examinations by using the section through the posterior 3 mm of the disk. To eliminate the effect of different magnifications and/or distortions, the distance between these points was measured automatically and divided by the largest mediolateral dimensions of the condyle. To assess the reliability of the measurements, four observers evaluated the position of the disk in the coronal plane. To assess the changes in position of the posterior 3 mm of the disk in the coronal plane in the closed- and opened-mouth positions, the Wilcoxon signed rank test for matched pairs was used. Interobserver measurement reliability was evaluated by using interclass correlation coefficients (ICCs)., Results: Analysis of the coronal closed-mouth disk position revealed a medial position of the TMJ disk relative to the condyle in 11 (21%) of 52 analyzed joints. In the opened-mouth position, the medial location of the disk was more frequent: 29 (85%) of 34 analyzed joints exhibited a medial position of the disk relative to the condyle in this plane. This increasingly medial position of the disk was statistically significant (P < or = .001). Measurement reliability assessment revealed sufficient results (ICC > or = 0.7)., Conclusion: At both closed- and opened-mouth MR imaging, a medially located TMJ disk seems to be within the normal range of variation. The disk seems to shift even more medially when the mouth is opened.

Objective: To investigate the influence of location and preparation design on the survival and complication rate of metal-free polymer crowns within a prospective clinical study., Methods: After randomization, a total of 114 (68 posterior and 46 anterior) single crowns were prepared, either with a chamfer finishing line or with a shoulder combined with occlusal reduction of at least 1 mm. Build-ups were made with a composite material, using the corresponding dentin adhesive. After making impressions with polyether material, polymer crowns were manufactured on stone dies and adhesively luted with resin cement. Follow-ups were scheduled after 1 month, 1 year, 2 years and 3 years. Documentation included failures and other complications, as well as ratings of esthetic and functional performance. After 3 years, data from 100 single crowns were statistically evaluated., Results: Within a minimal observation period of 3 years, 10 complications occurred, including 3 total fractures, 3 partial fractures and 3 decementations. Only 4 crowns (3 total fractures +1 partial fracture) had to be replaced, whereas 2 partial fractures could be repaired and all loosened crowns could be recemented. Kaplan-Meier survival analysis did not show any influence of location or preparation design on the complication rate. Esthetic and functional evaluation by the patients revealed a high acceptance of single polymer crowns, indicated by medians of 9-10 on a 10-point-scale., Conclusion: Within the 3 year observation period, it can be concluded that 0.5 mm chamfer and shoulder preparation ensure that the stability of metal-free polymer crowns for anterior and posterior teeth is acceptable. Long-term stability and wear behavior has still to be evaluated.

Previous studies on the prevalence of signs of temporomandibular disorders (TMD) in elderly people have used non-standardized and invalidated examination protocols. The prevalence of the different signs of TMD in this group is therefore still unclear. The aim of this study was to evaluate the prevalence of signs of TMD in subjects of advanced aged, using a standardized and validated examination protocol. Additionally, young subjects were examined as a control group. Fifty-eight old peoples' home inhabitants and 44 young subjects were examined using a standardized and validated examination protocol. Differences between the groups were assessed using Mann-Whitney U-test or t-test. Geriatric subjects more often exhibited objective symptoms of TMD (38% exhibited joint sounds on opening), but rarely suffered from pain (pain at rest: 0%, joint pain: 0%, muscle pain: 12%). In contrast, young subjects rarely exhibited objective symptoms (joint sounds: 7%), but suffered more frequently from pain (facial: 7%, joint pain: 16%, muscle pain: 25%). The mandibular range of motion was higher in young subjects. Differences between the groups with respect to joint sounds, muscular palpation pain and mandibular range of motion were significant. Although older subjects more frequently exhibited objective signs (joint sounds) of TMD, they rarely suffered from pain. In contrast, younger subjects rarely exhibited objective TMD signs but more frequently suffered from subjective signs (muscular pain on palpation) and facial pain.

The aim of this study was to investigate the reliability between different examiners when using the axis I of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The hypothesis was that the standardized RDC/TMD examination protocol enables calibrated examiners to evaluate all examination items reliably. After calibration training by the RDC/TMD calibration team including the calibration of palpation pressure and the performance of the standardized examination protocol, four examiners, blinded to the patients' medical histories examined 24 subjects in a randomized sequence. One experienced examiner was the standard (hierarchical calibration). The recorded measurements strictly followed the RDC/TMD. Intraclass correlation coefficients (ICC), bias and precision were calculated to estimate interrater reliability. Acceptable (0.75 > or = CC > 0.4) to excellent (ICC > 0.75) reliability was found for 20 of the 23 (87%) examinations. Only sub-retromandibular muscle palpation and joint sound vibration recordings on lateral excursion showed poor-results (ICC < or = 0.4). The RDC/TMD examination protocol enables calibrated examiners to perform most (87%) examination items with satisfactory reliability. Therefore multi-site studies based on the RDC/TMD examination protocol may become feasible, keeping in mind the unsatisfactory reliability of 13% of the items (clicking during laterotrusion to the ipsilateral side, palpation of the posterior and submandibular region).

Objectives: The purpose of this study was to evaluate the clinical performance of two adhesively retained composite core materials and compare them with a metal-added glass ionomer. The main objective evaluated was total or partial loss of build-ups during the treatment prior to crown cementation., Methods: In 187 patients, 315 vital and non-vital teeth were built up after randomisation with either Rebilda D (RD), Rebilda SC (RSC) or Ketac Silver Aplicap (KSA). The composites were applied in the total-etch-technique with the corresponding dentin bonding agent. The metal-added glass ionomer was used with a conditioner. One group of patients was treated by experienced dentists, the other by dental students, in order to evaluate the effects of different levels of experience. Data were analysed using Mann-Whitney-U-Test and binomial logistic regression., Results: The early failure rate (partial or total loss) of core build-ups before crown cementation was significantly higher for KSA (28.8%), as compared to RSC (15.3%, p=0.037) and RD (15%, p=0.025). Most failures were observed during the removal of the temporary crowns. The rate of replacements was between 3.0 (RD/dentists) and 20.4% (KSA/students). Furthermore, we found that build-ups made by students had a significantly higher risk of loss than those made by dentists (p=0.028)., Conclusions: Adhesively retained self-curing composites show a better clinical short-term performance and can be recommended as core build-up materials.

Statement of Problem: The improved mechanical properties of contemporary composites have resulted in their extensive use for the restoration of posterior teeth. However, the influence of fiber reinforcement, cementation technique, and physical stress on the fracture resistance of metal-free crowns is unknown., Purpose: This in vitro study evaluated the effect of fiber reinforcement, physical stress, and cementation methods on the fracture resistance of posterior metal-free Sinfony crowns., Material and Methods: Ninety-six extracted human third molars received a standardized tooth preparation: 0.5-mm chamfer preparation and occlusal reduction of 1.3 to 1.5 mm. Sinfony (nonreinforced crowns, n=48) and Sinfony-Vectris (reinforced crowns, n=48) crowns restoring original tooth contour were prepared. Twenty-four specimens of each crown type were cemented, using either glass ionomer cement (GIC) or resin cement. Thirty-two crowns (one third) were stored in humidity for 48 hours. Another third was exposed to 10,000 thermal cycles (TC) between 5 degrees C and 55 degrees C. The remaining third was treated with thermal cycling and mechanical loading (TCML), consisting of 1.2 million axial loads of 50 N. The artificial crowns were then vertically loaded with a steel sphere until failure occurred. Significant differences in fracture resistance (N) between experimental groups were assessed by nonparametric Mann-Whitney U-test (alpha=.05)., Results: Fifty percent of the Sinfony and Sinfony-Vectris crowns cemented with glass ionomer cement loosened after thermal cycling. Thermal cycling resulted in a significant reduction in the mean fracture resistance for Sinfony crowns cemented with GIC, from 2037 N to 1282 N (P=.004). Additional fatigue produced no further effects. Fiber reinforcement significantly increased fracture resistance, from 1555 N to 2326 N (P=.001). The minimal fracture resistance was above 600 N for all combinations of material, cement and loading., Conclusion: Fracture resistance of metal-free Sinfony crowns was significantly increased by fiber reinforcement. Adhesive cementation may be recommended to avoid cementation failure.

Objectives: Effects of calibration on interrater agreement in evaluating magnetic resonance (MR) images of the temporomandibular joint (TMJ) have already been examined. The objectives of the present study were to assess to what extent the quality of MR images of the TMJ influences interrater agreement and to evaluate interrater agreement with respect to image quality assessment., Methods: Two non-calibrated medical radiologists and two general dentists evaluated sagittal images of 100 TMJs for both a rating of the image quality and the performance of five diagnostic tasks. The agreement between these raters with respect to the diagnoses was evaluated. Additionally, two additional raters, calibrated during a 5 h training including the evaluation of 70 MR images, also evaluated the diagnostic aspects and the image quality, on the basis of objective criteria. The agreement between the subjective diagnoses of the non-calibrated raters and the objective diagnoses of the calibrated raters was evaluated. Afterwards, the subjective and the objective quality assessments were compared using kappa statistics., Results: When good quality images were evaluated, higher kappa values were obtained for all diagnostic categories by the non-calibrated raters (mean Deltak for making diagnoses >0.1). This finding was confirmed by the value obtained for the agreement between the non-calibrated and the calibrated raters. The non-calibrated raters were in good agreement (k=0.67, standard error +/-0.09) with the calibrated raters for assessment of image quality., Conclusion: The present study shows that it is possible even without calibration to obtain a better interrater agreement when higher quality MR images of the TMJ are evaluated.

Objective: We sought to determine the prevalence of joint diseases in patients with either of 2 forms of myofascial pain (with and without limited mouth opening) and to verify the accuracy of temporomandibular joint-related clinical diagnoses through the use of magnetic resonance imaging (MRI)., Study Design: On the basis of the results of a clinical examination carried out according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), 61 patients were divided into 2 subgroups. The first group consisted of 36 patients who had myofascial pain with limited mouth opening (MPLO), whereas the other 25 patients were diagnosed with myofascial pain without limited mouth opening. MRI was carried out on all patients. The clinical joint-related diagnoses from RDC/TMD were compared with MRI results., Results: Patients with MPLO often had joint diseases that were not detected by means of a clinical examination alone. The kappa statistic was used to compare MRI and clinical diagnoses, confirming poor agreement in patients with MPLO (kappa=0.13) and acceptable agreement in patients with myofascial pain without limited mouth opening (kappa=0.72)., Conclusion: Restricted mandibular mobility is frequently associated with temporomandibular joint diseases that were not identified during a clinical examination. Therefore, an adaptation of the classification scheme used for the RDC/TMDs may result in the improvement of the sensitivity of clinical joint-related diagnoses, especially in patients with MPLO.

Aims: To investigate the course of myofascial pain defined by Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) over a period of 5 years, and to identify prognostic factors from baseline data., Methods: Subjects were 155 consecutive patients and 80 community cases identified from an age-stratified representative population sample; all met the primary selection criterion of reporting pain in the temporomandibular joint (TMJ) or masticatory muscles. The 2 groups were combined to yield a total sample of 235 subjects (50 male, 185 female; mean age = 39 years). Subjects were evaluated at baseline, 1 year, 3 years, and 5 years by trained examiners using standardized, reliable methods. Psychological and behavioral factors were assessed by self report., Results: According to RDC/TMD criteria, 50 (31%) of the 165 subjects presenting with myofascial pain (MFP) at baseline continued to have their disorder over a period of 5 years; 55 (33%) remitted, and 60 (36%) were recurrent cases. Bivariate statistics and multivariate logistic regression analyses indicated that baseline pain frequency, number of painful palpation sites, and total number of body sites with pain were significant predictors of persistent vs remitted and recurrent cases. No predictors that distinguished remission vs recurrence could be identified. Thirty subjects from the 70 without a diagnosis of MFP at baseline developed a new MFP. A high baseline somatization score (without pain items) was a significant risk factor for onset of MFP., Conclusion: Muscle disorders classified by RDC/TMD are predominantly chronic or fluctuating pain conditions, with a modest probability (31%) of remission.

The purpose of this study was to evaluate the possible structural variations of axial condyle morphology and horizontal condylar angle between patients with internal derangement and asymptomatic volunteers. Forty-five symptomatic patients and 31 asymptomatic volunteers (AV) were included in this study. All subjects had bilateral high-resolution magnetic resonance imaging scans. Axial condyle morphology was evaluated using these images and classified into four diagnostic groups: convex, flat, and concave anterior surfaces, and tapered form. The angulation between the condylar long axis and the transversal plane was then measured. A Wilcoxon-Whitney-Mann-U-test demonstrated no significant differences in the horizontal angulation of the patients with disk displacement with reduction (DDR) (24.35+/-9.31) as compared to patients with displacement without reduction (DDN) (25.61+/-10.11) and asymptomatic volunteers (25.68+/-9.31) (AV). Eighty percent of the flat type condyles and 73.3% of the tapered type condyles belonged to the symptomatic patients with disk displacement with reduction (DDR) and without reduction (DDN). Chi-square test demonstrated significant differences between the diagnostic groups of condyle types (p<0.01). A comparison of the angular difference of right and left joints of asymptomatic volunteers and patients using the Wilcoxon-Whitney-Mann-U test showed that the results of the asymptomatic volunteers were significantly lower (p = 0.05). The conclusion that an increase in the horizontal condylar angle is a predisposing factor for the development of internal derangement or that the derangement develops during the prognosis of the disorder could not be clearly stated based on the results of this study. It is proposed that the difference between condyle morphology in patients with disk displacement and asymptomatic volunteers may be a result of the remodeling or degeneration caused by the disorder.

Computed tomography (CT) and magnetic resonance imaging (MRI) are well established imaging modalities to examine the TMJ. MRI is superior to CT in delineating the morphological architecture of the TMJ, not only in cases of normal anatomy, inflammation or tumors, but also if dysfunction of the TMJ is present. This review article presents anatomy as well as imaging strategies of the TMJ.

Statement of Problem: Improved mechanical properties of contemporary composites has resulted in the extended use of composites for the restoration of posterior teeth. Although the indication of polymers was extended to metal-free individual crowns, the influence of tooth preparation design and cementation methods on the stability of these artificial crowns remains unknown., Purpose: This in vitro study evaluated the effect of axial tooth preparation design, occlusal dimension, and cementation technique on the fracture resistance of metal-free posterior Artglass crowns., Material and Methods: Seventy-two extracted human third molars, assigned to experimental groups by size, received standardized tooth preparation. Axial tooth preparation included an invasive approach with 1-mm deep shoulder and a less invasive 0.5-mm chamfer preparation, whereas occlusal reduction was either 0.5 mm or 1.3 mm. Artglass crowns that restored the original tooth contour were cemented with 3 cements: zinc phosphate cement (ZnP), glass ionomer cement (GIC), or a resinous cement in combination with a dentinal bonding agent. After 10,000 thermal cycles between 5 degrees C and 55 degrees C, artificial crowns were vertically loaded until compression to failure. Significant differences of fracture loads between experimental groups were assessed by paired Mann-Whitney U tests., Results: Minimal fracture resistance for all combinations excluded 500 N. However, 9 of 24 Artglass crowns cemented with ZnP loosened after thermocycling. Adhesive cementation resulted in a significantly greater fracture resistance compared with GIC and ZnP (P=.02). Increased occlusal thickness (0.5 to 1.3 mm) resulted in greater stability, whereas a 1-mm deep shoulder tooth preparation did not improve durability compared with a 0.5-mm chamfer finishing line., Conclusion: A minimally invasive 0.5-mm axial chamfer tooth preparation combined with sufficient occlusal reduction and adhesive cementation recorded the greatest stability for posterior metal-free Artglass crowns.

Within the framework of an on-going prospective clinical study begun in 1985, 120 adhesive-fixed partial dentures (AFPD) continued to be examined. The manufacture and the fitting of the AFPDs were carried out following a standard procedure. The preparation technique and the metal framework conditioning (silica-coating, sand-blasting and electrochemical etching) has varied throughout the duration of the study. Using Kaplan-Meier analysis, the survival rate was determined and an analysis of risk with regard to location factors (anterior, posterior; maxilla, mandible), conditioning and preparation techniques (retentive/non-retentive) was determined using the Cox regression model. The location of the AFPD had no influence on the survival rate. The survival time was determined mainly by the preparation technique. Strict preparation of seating grooves and pin holes made a 95% survival rate possible after 10 years (Kaplan-Meier estimation). Without retention, the risk of failure increased by a factor of 3.7.

This study determined the variability of temporomandibular joint (TMJ) disk position in medial, central, and lateral aspects of the joint using magnetic resonance imaging (MRI). Subjects had clinical evidence of reciprocal TMJ clicking (N = 123) or restricted mandibular motion (N = 52). Eighty-nine asymptomatic volunteers provided a control group. Disk position was quantified on MRI by measuring the angle formed by a line through the middle of the condyle and perpendicular to the Frankfort plane and a line through the same midpoint of the condyle and tangential to the posterior-most aspect of the disk. The disk position in asymptomatic TMJs varied considerably with a tendency toward farther anterior placement in more lateral images. In 47 TMJs from a total of 52 TMJ5 (90%), restricted mobility was associated with anterior disk displacement (ADD) without reduction. The disk position demonstrated a mean displacement of 77 degrees without significant differences at the medial and lateral aspects of the condyle. One hundred TMJs from a total of 123 TMJs (81%) with reciprocal clicking demonstrated ADD with reduction. Tomograms revealed larger lateral displacements or rotational displacements in these joints, whereas medial images frequently showed similar ranges of disk positions as compared with asymptomatic TMJs. The results suggest that disk positions of up to +15 degrees on medial tomograms and +30 degrees on lateral tomograms should be regarded as normal variations. Furthermore, multisection analysis of all parasagittal images improved the separation between disk displacement and asymptomatic TMJs.

After 7 years of clinical experience, the alumina ceramic, In-Ceram, can be regarded as a well-proven material for all-ceramic crowns. Because of its high strength, this material can also be used for small all-ceramic fixed partial dentures. First attempts at using this material for resin-bonded prostheses revealed a high failure rate. The aim of this article is to present a new preparation design for all-ceramic resin-bonded fixed partial dentures that allows fabrication of highly esthetic and also tooth-saving adhesive prostheses. Clinical results over a period of 4 years revealed that they are strong enough to replace anterior teeth. Nevertheless, positive long-term clinical results are necessary before a general recommendation can be given for this kind of prosthesis.

Objective of this study was to evaluate the diagnostic value of 3-D computed axiography to detect anterior disk displacements (ADD) of the TMJ. 65 patients with MRI confirmed ADD with reduction and 27 patients with ADD without reduction were examined by 3-D computed axiography. 44 healthy volunteers with normal disk position and joint function served as controls. A descriptive analysis of the axiographic opening/closing cycle revealed significantly higher rates of abrupt deviations, accelerations/decelerations, and crossings for ADD with reduction compared to healthy volunteers. A new axiographic index reduced the number of false positive to 10% and false negative to 14% of the diagnosis. ADD without reduction was characterized by significantly shorter opening curves. The optimum split point at 11 mm, resulted in 10% false positive and 20% false negative diagnosis. However, the diagnostic value of computed axiography was reduced by the significant influence of the clicking or limited joint on the contralateral TMJ.

Resin-bonded fixed partial dentures (FPD) with a metal framework have some disadvantages: a grey shimmer of the metal wings through the abutment teeth, a higher corrosion rate, and an allergenic potential of the non-precious alloys used. The Al2O3 ceramic In-Ceram seems to be strong enough to serve as a framework for resinbonded all-ceramic FPDs. Because of the fact that ceramic wings often don't have enough inter-occlusal space, a new preparation design was developed. The objective of this study was to determine the influence of load orientation (45 degrees and 60 degrees) and the design of the interproximal connector on the stress distribution in the bridges. A 3-dimensional finite-element model was developed to simulate the anatomical situation. The biting force was assumed as 250 N and oriented in oro-buccal direction. The loading-point was palatal 1.5 mm beneath the incisal edge. It was found that stress generally increased with an angle of the biting force of 60 degrees. A small interdental connector (3 mm height) and/or strong interdental separation resulted in stresses of up to 455 MPa (45 degrees) or 534 MPa (60 degrees). Less separation with rounded edges and a higher connector (4 mm) reduced the stress to 122 MPa (45 degrees) and 143 MPa (60 degrees). Due to an average tensile strength of In-Ceram at 340-400 MPa, an all-ceramic resin-bonded FPD may only be recommended if the height of the connector could be minimum 4 mm. Rounded edges and little interdental separation are significant for stress reduction.

One hundred forty-one adhesive fixed partial dentures were placed under controlled conditions for a 6-year longitudinal study. The influence of location (anterior/posterior, maxilla/mandible), tooth preparation techniques (retentive/less invasive), and four different methods of metal conditioning (sandblasting/electrolytic etching and/or pyrolytic/tribochemical silane coating) on the survival rate was investigated. Failures (23 of 24) were caused by loss of adhesion at the metal-cement interface. The retentive tooth preparation reduced the risk of failure to almost one twentieth, but the intraoral location did not influence survival time. The effect of silane-coating on longevity was extremely positive and was not reflected by successful retainers.

53 patients with 120 endosseous implants could be re-evaluated after a mean period of 2.7 years (maximum 5 years). Using casts from the upper with transfer posts and lower jaw, we measured the deviation of the implant axes from their ideal direction and localisation. Furthermore, we tried to find out, whether an unfavourable localisation compromised the prognosis of osseointegrated implants. Ideal, axial load by the prosthetic construction was often impossible because of unfavourable localisation of the implants. In a rank correlation analysis we found a significant influence of unfavourable localisation on prognosis in the group of hinge bars. Further weak correlations were revealed between loss of attachment and gingiva index which in turn was correlated with the plaque index.

A total of 107 bonded bridges could be re-evaluated after a mean period of 2.3 years and a maximum of 5 years. The preparation of mechanical retentive aids, such as grooves and bores resulted in a significant reduction of failure rates after one year. Electrolytical etching or silicoating of the CoCr restorations failed to have any effect on the failure rates of those bridges that were provided with adequate mechanical retention.

25 patients with reciprocal clicking in one or both temporomandibular joints were examined clinically and with an electronic axiographic system (SAS-System). Studying the direction of the sudden change of the condylar path during clicking, we established a tentative differential diagnosis of "centric anterior dislocations" of the disc and "eccentric posterior dislocations". Interpreting the axiographic pathways we found an eccentric posterior dislocation of the disc in 20 TMJs. But in at least 11 cases, which could be re-evaluated by magnetic resonance tomography (CMR), the diagnosis "eccentric posterior dislocation" was false. As we found several variations of anterior dislocations with a cranial and lateral deviation of the condylar path during opening clicking, the diagnosis of "eccentric disc dislocations" established by axiography was not reliable.

It's be reported on the clinical behaviour of 37 for the first time used adhesive bridges and of 11 new installations integrated since 1985. The comparatively high failure rate is explained by an insufficient standardization and above all by preparation defects.

From 1981 to 1984 987 patients of the Allergy Department of the Würzburg University Dermatological Hospital were evaluated with patch testing using a standard series; 199 patients were additionally tested with a specially composed metal battery. The results of the standard series with regard to the four metals contained in it, namely mercuric chloride, nickel sulphate, cobalt sulphate and potassium bichromate, were contrasted with the test results of the metal battery. Here there were conspicuous discrepancies between the two collectives, above all, with respect to cobalt. In comparison to the data contained in the literature we found appreciable differences in the metals copper, cobalt and potassium bichromate.