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Mastication is a vital human function and uses an intricate coordination of muscle activation to break down food. Collection of detailed muscle activation patterns is complex and commonly only masseter and anterior temporalis muscle activation are recorded. Chewing is the orofacial task with the highest muscle forces, potentially leading to high temporomandibular joint (TMJ) loading. Increased TMJ loading is often associated with the onset and progression of temporomandibular disorders (TMD). Hence, studying TMJ mechanical stress during mastication is a central task. Current TMD self-management guidelines suggest eating small and soft pieces of food, but patient safety concerns inhibitin vivoinvestigations of TMJ biomechanics.For this purpose, we have developed a state-of-the-artin silicomodel, combining rigid body bones, finite element TMJ discs and line actuator muscles. To solve the problems regarding muscle activation measurement, we used a forward dynamics tracking approach, optimizing muscle activations driven by mandibular motion. We include a total of 256 different combinations of food bolus size, stiffness and position in our study and report kinematics, muscle activation patterns and TMJ disc von Mises stress.Computed mandibular kinematics agree well with previous measurements. The computed muscle activation pattern stayed stable over all simulations, with changes to the magnitude relative to stiffness and size of the bolus. Our results agree with the clinical guidelines regarding bolus modifications as smaller and softer food boluses lead to less TMJ loading. The results help to strengthen the confidence in TMD self-management recommendations, potentially reducing pain levels of patients.

Background Delayed gadolinium enhanced MRI of cartilage (dGEMRIC) is a quantitative method for assessment of glycosaminoglycan content in connective tissues. We hypothesize that the early diagnosis of degenerative changes in the temporomandibular joint could be diagnosed using dGEMRIC technique. Purpose To test the compositional MRI technique, dGEMRIC, at 3 Tesla to diagnosis early the degenerative changes in the fibrocartilaginous disc of the temporomandibular joint (TMJ) in patients with temporomandibular disorders (TMD) and to compare the dGEMRIC index of patients to the healthy volunteers. Methods Six volunteers (two men, four women; 20.8÷28.1 years) and eleven patients (22 TMJs, seven women, four men; 24÷54 years) were recruited for this prospective trial. Only patients with no morphological abnormality on MRI and without disc dislocations were included. Volunteers were used as a control group. The PD-weighted FSE sequence and the 3D GRE (DESS) sequence protocols were performed for morphological assessment. The Inversion recovery (IR) sequence was performed for T1 relaxation time measurements and intra-venous (IV) contrast agent administration was used according to the dGEMRIC protocol. T1 maps were calculated offline and ROIs were drawn on TMJ discs by a specialist trained in TMD disorders. Statistical evaluation was performed by ANOVA and correlations were calculated. Results The difference between the dGEMRIC values in the TMJ articular discs of the patients and the volunteers was statistically significant (P = .019). After contrast agent administration the T1 values dropped in both groups. In patient group was the T1 drop stronger (−54% from initial pre-contrast value), while in control group was the T1 drop less pronounced (−46% from initial pre-contrast value). Conclusions dGEMRIC seems to be a useful, compositional, quantitative method, suitable also for small joints, such as the articular disc of the TMJ. The results of the dGEMRIC index in the articular disc of the TMJ imply a lower GAG content in patients with TMJ disorders.

Objectives This study aimed to characterize surface properties such as roughness (Ra) and surface-free energy (SFE) of glazed and polished yttria-stabilized zirconia and to evaluate in vitro adherence of fungus Candida albicans and salivary bacteria, Staphylococcus epidermidis, mixed with C. albicans to these substrata. Additionally, the influence of salivary proteins (albumin, mucin and α-amylase) on yeast adhesion was studied. Material and methods Ra and SFE of glazed and polished zirconia discs were measured. Specimens were wetted with saliva and salivary proteins prior to incubation with C. albicans and mixed suspension of C. albicans and S. epidermidis for 24 hr, respectively. Microbial adhesion was quantified by counting colony-forming units (CFU). Differences in physicochemical properties were proved by t test. "Linear mixed model" with the factors "type of surface" and "wetting media" was applied to analyse the effects on fungal adhesion (p Results SFE and Ra of glazed specimens were significantly higher than corresponding values of polished ones. The wetting media significantly changed the fungal binding (p = .0016). Significantly higher quantities of adhering fungi were found after mucin incubation compared to saliva (p = .004). For the factor "surface" as well as the interaction between "surface" and "wetting media," no statistically significant differences have been found. In mixed suspension, the growth of Candida was completely prevented. Conclusions Glazed and polished zirconia differs in terms of physicochemical surface properties. These differences appear to be modulated by pellicle coating affecting the biomass of adhered Candida. Mucin seems to be good binding sites for adhesion of C. albicans.

Sleep bruxism is an oral parafunction that involves involuntary tooth grinding and clenching. Splints with a colored layer that gets removed during tooth grinding are a common tool for the initial diagnosis of sleep bruxism. Currently, such splints are either assessed qualitatively or using 2D photographs, leading to a non-neglectable error due to the 3D nature of the dentition. In this study we propose a new and fast method for the quantitative assessment of tooth grinding surfaces using 3D scanning and mesh processing. We assessed our diagnostic method by producing 18 standardized splints with 8 grinding surfaces each, giving us a total of 144 surfaces. Moreover, each splint was scanned and analyzed five times. The accuracy and repeatability of our method was assessed by computing the intraclass correlation coefficient (ICC) as well reporting means and standard deviations of surface measurements for intra- and intersplint measurements. An ICC of 0.998 was computed as well as a maximum standard deviation of 0.63 mm2 for repeated measures, suggesting an appropriate accuracy of our proposed method. Overall, this study proposes an innovative, fast and cost effective method to support the initial diagnosis of sleep bruxism.

Mastication is the motor task with the highest muscle activations of the jaw region, potentially leading to high temporomandibular joint (TMJ) loading. Since increased loading of the TMJ is associated with temporomandibular disorders (TMD), TMJ mechanics during chewing has potential clinical relevance in TMD treatment. TMD self-management guidelines suggest eating soft and small pieces of food to reduce TMJ pain. Since TMJ loading cannot be measured in vivo, due to patient safety restrictions, computer modeling is an important tool for investigations of the potential connection between TMJ loading and TMD. The objective of this study is to investigate the effect of food bolus variables on mechanical TMJ loading to help inform better self-management guidelines for TMD. A combined rigid-body-finite-element model of the jaw region was used to investigate the effect of bolus size, stiffness, and position. Mandibular motion and TMJ disc von Mises stress were reported. Computed mandibular motion generally agrees well with previous literature. Disc stress was higher during the closing phase of the chewing cycle and for the non-working side disc. Smaller and softer food boluses overall lead to less TMJ loading. The results reinforce current guidelines regarding bolus modifications and provide new potential guidelines for bolus positioning that could be verified through a future clinical trial. The paper presents a first in silico investigation of dynamic chewing with detailed TMJ stress for different bolus properties. The results help to strengthen the confidence in TMD self-management recommendations, potentially reducing pain levels of patients.

The delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) is a useful tool for the evaluation of a repair tissue status after cartilage transplantation. A previous study showed the feasibility of dGEMRIC at 3 Tesla in TMJ. This case report describes the application of dGEMRIC to a TMD patient. A 27 years old female patient reported TMJ (VAS 87) with increasing intensity. The examination according to RDC/TMD showed myofacial pain (group I) and arthralgia of the right and left joint (IIIa). The graded chronical pain score showed grade III. The conventional MRI showed no sign of discus dislocation. T2 mapping showed a significant signal in homogeneity in both disci, as well as an increased amount of fluid in both compartments and a flattened disc in the lateral area. The application of dGEMRIC with patients suffering from temporomandibular disorders could be very well suited for early detection of onset pathological change in fibrocartilage.

The masticatory region is an important human motion system that is essential for basic human tasks like mastication, speech or swallowing. An association between temporomandibular disorders (TMDs) and high temporomandibular joint (TMJ) stress has been suggested, but in vivo joint force measurements are not feasible to directly test this assumption. Consequently, biomechanical computer simulation remains as one of a few means to investigate this complex system. To thoroughly examine orofacial biomechanics, we developed a novel, dynamic computer model of the masticatory system. The model combines a muscle driven rigid body model of the jaw region with a detailed finite element model (FEM) disk and elastic foundation (EF) articular cartilage. The model is validated using high-resolution MRI data for protrusion and opening that were collected from the same volunteer. Joint stresses for a clenching task as well as protrusive and opening movements are computed. Simulations resulted in mandibular positions as well as disk positions and shapes that agree well with the MRI data. The model computes reasonable disk stress patterns for dynamic tasks. Moreover, to the best of our knowledge this model presents the first ever contact model using a combination of EF layers and a FEM body, which results in a clear decrease in computation time. In conclusion, the presented model is a valuable tool for the investigation of the human TMJ and can potentially help in the future to increase the understanding of the masticatory system and the relationship between TMD and joint stress and to highlight potential therapeutic approaches for the restoration of orofacial function.

Tumor surgery in the orofacial region frequently requires resection of major parts of the jawbone,.. .

Objectives Anterior disk dislocation (ADD) without reposition in the temporomandibular joint (TMJ) may be associated with morphological changes in the retrodiscal region of the bilaminar zone presenting as pseudo-disk (PD). The present study was initiated to investigate the development of retrodiscal fibrosis in a period of 4–8 years and to assess if patients with a PD show differences in the clinical and radiologic findings versus patients without a PD. Materials and Methods In a retrospective follow-up study of 33 consecutive patients with ADD without reposition in one or both TMJs, a clinical and MRI-supported evaluation was conducted 4 to 8 years after baseline diagnosis. Results In 45 % of the TMJs with ADD without reposition, a PD could be identified. Twenty-one of 31 patients who showed pain at the baseline examination (VAS mean 56 ± 38) were pain free. The mouth opening capacity (MO) of the mandible could be increased in 80 %. There were no statistical significant differences between patients with or without PD in these clinical features. The MRI parameters effusion and translation showed a statistical tendency for more improvement in the group with PD (p = 0.061, 0.064). Conclusion In about half of the patients, a structure corresponding to a pseudo-disk developed during follow-up. Pain and the mouth opening capacity improved in all patients independent of the development of a PD. Clinical Relevance Detection of a PD during follow-up of patients with ADD without spontaneous reposition does neither predict favorable nor worse therapy response and clinical course.

Temporomandibular joint disorders (TMD) are common dysfunctions of the masticatory region and are often linked to dislocation or changes of the temporomandibular joint (TMJ) disc. Magnetic resonance imaging (MRI) is the gold standard for TMJ imaging but standard clinical sequences do not deliver a sufficient resolution and contrast for the creation of detailed meshes of the TMJ disc. Additionally, bony structures cannot be captured appropriately using standard MRI sequences due to their low signal intensity. The objective of this study was to enable researchers to create high resolution representations of all structures of the TMJ and consequently investigate morphological as well as positional changes of the masticatory system. To create meshes of the bony structures, a single computed tomography (CT) scan was acquired. In addition, a high-resolution MRI sequence was produced, which is used to collect the thickness and position change of the disc for various static postures using bite blocks. Changes in thickness of the TMJ disc as well as disc translation were measured. The newly developed workflow successfully allows researchers to create high resolution models of all structures of the TMJ for various static positions, enabling the investigation of TMJ disc translation and deformation. Discs were thinnest in the lateral part and moved mainly anteriorly and slightly medially. The procedure offers the most comprehensive picture of disc positioning and thickness changes reported to date. The presented data can be used for the development of a biomechanical computer model of TMJ anatomy and to investigate dynamic and static loads on the components of the system, which could be useful for the prediction of TMD onset.

Introduction T2 mapping, as a quantitative biochemical MRI-technique that provides information on water and collagen fiber content and composition, was shown to be clinically feasible for the evaluation of healthy temporomandibular joints. Objectives The aim of our study was to compare the T2 values of whole discs in patients with and without disc dislocation, to evaluate the possible influence of morphological findings on T2 values and to assess the interrater agreement. Methods Sixty-six patients were included in the study. Three experienced examiners assessed the perceptibility of the morphological parameters and the position of the articular disc on the morphological MR images. On the T2 maps, the T2 values of the region-of-interest (ROI) were assessed. Results The ICC (Intraclass Correlation Coefficient) for the reproducibility of the T2 values was 0.717. The assessment of the morphologic parameters was excellent or good in most of the discs. There was no significant difference in the T2 values based on disc position or signal intensity. But, a statistically significant moderation effect (p = .014) could be identified, indicating that the effect of disc position differs for different signal intensities. Condyle position, effusion, and degenerative changes showed pronounced moderation effects on the T2 values. Conclusion Due to the high sensitivity to effusion, T2 mapping currently seems to be unsuitable as a diagnostic tool for routine use in the temporomandibular joint. The moderation effect clearly shows the influence of factors such as signal intensity, effusion, arthrosis, and condyle position. Perhaps a solution for these problems could be the development of dedicated TMJ coils for higher field strengths at 7.0 T.

To evaluate the regional collagen fiber network in the human temporomandibular joint (TMJ) disc by using biochemical magnetic resonance imaging (MRI) and quantitative histology.MRI of 5 heads (10 TMJ discs) obtained from partially dentate or edentulous cadavers was performed at 3-Tesla MRI by using a flexible, 8-channel transmit-receive coil. After MRI, all 10 discs were processed histologically. Percentages of coronal, sagittal, and transverse collagen fibers were assessed stereologically for the anterior, central, and posterior parts of the disc. An anisotropy index was calculated for collagen fiber arrangement in all three regions of interest.In the central part of the TMJ disc, collagen fibers were arranged anisotropically with a preferentially sagittal direction. In the anterior and posterior parts, evidence for fibers being arranged isotropically (randomly) without preferred direction was found. Mean MRI T2 values appeared to be correlated with the anisotropy index of collagen fibers (r = -0.45; P.05). When tested individually, T2 values of the isotropic anterior and posterior disc regions showed a partial but significant correlation with the anisotropy index of collagen fibers (r = -0.54; P.05), whereas the anisotropic central part did not (P.05).This study has provided the first systematic comparison of quantitative data on collagen fiber isotropy and anisotropy assessed in histologic sections with biochemical quantitative MRI for human TMJ fibrous cartilage.

Aims: To explore potential differences in characteristics of patients that might account for sex-specific differences in temporomandibular disorders (TMD). Methods: A total of 502 patients presenting with TMD during 2000 to 2002 at the Outpatient Unit for Functional Disorders of the Medical University of Vienna underwent detailed evaluation of their medical history and assessment of clinical findings. The data obtained were assessed for sex-specific differences by analysis of variance and multiple regression. Results: Overall, 404 females (mean age ± SD: 40 ± 16 years; range 12 to 96 years) and 98 males (mean age 41 ± 16 years; range 16 to 78 years) were included. Their rating of their pain on a visual analog scale (VAS) showed a significantly higher pain intensity for females than for males (P = .004). Clinical assessment showed a significantly lower degree of mouth opening for females than for males (P < .001). While no sex-specific differences were noted for clicking phenomena of the temporomandibular joint (TMJ) and for the bite class of the patients, bite anomalies were significantly more frequent in male patients (P = .03). Palpation of masticatory muscles and the TMJ revealed significantly higher tenderness on palpation in female as compared to male patients (P = .001). Grouping by clicking, crepitation, and bruxism also showed greater pain (VAS) and more tenderness on palpation in females versus males. Females also showed peaks of prevalence of TMD in the age group below 25 years and in the group 55 to 60 years, whereas males had a more even age distribution. No external factors, such as exposure to stress, were found that moderated the sex difference. Conclusion: Female TMD patients showed greater pain and muscle tenderness on palpation as compared to male TMD patients. They also showed a different age distribution of prevalence of TMD. These results were independent of subjective symptoms, clinical findings, and external factors. J OROFAC PAIN 2013;27:42–50. doi: 10.11607/jop.970

Objectives Microleakage testing of dental materials is a commonly accepted evaluation technique of margin integrity. Thermocycling has been utilized by many researchers to study the influence of temperature extremes on the marginal gap of cemented restorations. The aim of this investigation was to analyze microleakage data on cemented crowns, published in the dental literature until Dec 2009, to identify methodological factors that might potentially affect the results of in vitro microleakage tests and to compare the results. Methods The following databases were included: Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations and Ovid MEDLINE(R) 1950 to Present, Ovid-MEDLINE(R) 1950 to Present with Daily Update, EMBASE, EBM Reviews – Cochrane Database of Systematic Reviews and Pub Med. The search was limited to articles in English, French, Italian and German published until the end of 2009. Classical reviews, comments, animal studies, in vivo articles and studies investigating restorative materials or milk teeth were excluded. 33 different studies were finally selected. The studies were entered in a database and compared using selected literature criteria: sample, restoration procedures, thermocycling and mechanical cycling, evaluation method. For statistical analysis only 16 studies could be applied. Results It was not possible to make a quantitative synthesis of most of the data, due to the heterogeneity of the studies concerning methods, treatment and outcome variables. Comparing the main groups of materials (ceramics, gold alloys and base metal alloys), no significant difference in the proportion of teeth without microleakage was found. Furthermore no significant difference in the proportion of teeth showing microleakage less than two third of the wall or teeth showing microleakage including the entire wall was found. Using the mean values in the meta-analysis instead of the proportions does not change the results. Confidence intervals could only be calculated for two materials (gold alloy, metal alloy). No difference between materials was found. Significance Comparison of the results from different studies is critical, since there are no generally accepted standards for experimental parameters, such as type and concentration of the storage solution, time of storage, temperature during storage, type and duration of thermal cycling and/or mechanical cycling, and the scoring criteria. There is lack of standardization of experimental conditions, which would ensure confidence in the studies and would further allow better comparability of various results.

Purpose: The present study evaluated implant survival/success rate, peri-implant parameters and prosthodontic maintenance efforts for four implant-supported mandibular overdentures (IOD) rigidly retained on either milled bar or double crowns (telescopic) attachments. Material and methods: In a randomized prospective trial, 51 patients with edentulism received four mandibular interforaminal implants and complete maxillary dentures. For IOD, rigid denture stabilization was chosen randomly selecting 26 patients for milled bars (group I) and 25 patients for double (telescopic) crowns (group II). During a 3-year follow-up period, implant survival/success, peri-implant parameters (marginal bone resorption, pocket depth, plaque-, bleeding-, gingival index [BI and GI], calculus) and prosthodontic maintenance efforts were evaluated and compared between both retention modalities used. Results: Forty-five patients (23 group I, 22 group II) were available for a 3-year follow-up (dropout rate: 11.8%) presenting a high implant survival/success rate (100%). Peri-implant marginal bone resorption, pocket depth as well as BI and GI did not differ for both rigid retention modalities. However, annually higher values for plaque- (NS) and calculus index (P

Objectives: The aim of this study was to evaluate soft tissue development at concave circular macro-grooved titanium abutments in healed sites. Material and methods: In a split-mouth pilot study 10 patients received two implants each at healed posterior sites in contralateral maxillary or mandibular jaw quadrants. Either circular macro-grooved concave study abutments or conventional convex control abutments were immediately provisionalized and received permanent crowns 3 months postimplantation. Marginal bone level, papilla index, modified plaque and bleeding index were recorded. The esthetic outcome was evaluated with standardized perpendicular pictures according to the Pink Esthetic Score (PES). Statistical analysis included the description of all variables by mean value, standard deviation and range. PES values were compared using the Wilcoxon signed rank test for paired data. Results: Cumulative survival rate for all 20 implants was 100%. At the 1-year follow–up, there was no statistical significant difference of marginal bone levels between sites restored with the study (−0.11 ± 0.77 mm) vs. the control (−0.34 ± 0.53 mm) abutments (P>0.05). Esthetic evaluation (PES) revealed statistically significant differences in scores between the study group [study abutment group] (7.2 ± 2.82, 8 ± 1.89) and the control group [control abutment group] (9.5 ± 1.58, 10.5 ± 1.72) at the time of prosthetic delivery and the 1-year follow-up. Whereas PES scores for mesial papilla at control sites at the 1-year follow-up demonstrated statistically significant higher values, both soft tissue level and soft tissue contour at control sites revealed statistically significantly higher PES values (P

Krennmair G, Seemann R, Piehslinger E. Dental implants in patients with rheumatoid arthritis: clinical outcome and peri-implant findings. J Clin Periodontol 2010; 37: 928–936. doi: 10.1111/j.1600-051X.2010.01606.x. Abstract Purpose: Implant prosthodontic treatment outcomes for patients suffering from autoimmune rheumatoid arthritis (RA) with or without concomitant connective tissue diseases (CTD) were evaluated. Material and Methods: Thirty-four female patients' (25 isolated RA; nine RA+CTD) implant survival/success rate, peri-implant conditions (marginal bone loss, pocket depth, plaque index, gingiva index and bleeding index) and incidence of prosthodontic maintenance were retrospectively evaluated. Results: Implants evaluated presented a high implant survival (100%) and a 3.5-year success (93.8%) rate during the follow-up programme (mean 47.6 month) without difference between isolated RA (94.6%) and RA and concomitant CTD (92.3%), respectively. In isolated RA, acceptable marginal bone resorption (mean: 2.1 mm; SD: 0.5 mm), pocket depth (mean: 2.8 mm; SD:3.2 mm) and healthy soft-tissue conditions (plaque/bleeding/gingiva index Grade 0 in 80%) were noticed. However, patients with RA+CTD presented increased bone resorption (mean: 3.1 mm; SD: 0.7 mm) and more vulnerable soft-tissue conditions (higher bleeding index) differing significantly to patients with isolated RA (p

PURPOSE: Effectiveness of splint therapy or exercise therapy has been discussed controversially in literature. This retrospective study was intended to compare effectiveness of splint therapy or exercise therapy alone or with a combination of both methods. MATERIAL OR PATIENTS AND METHODS: The study evaluated 97 patients from the Clinic of Temporomandibular Dysfunction. Pain sensation, muscle pain on palpation, mouth opening and a subjective anamnestic index were assessed before and after therapy and compared. 29 patients received exercise therapy alone (group ET), 37 patients splint therapy alone (group S), and 31 patients a combination with splint therapy plus exercise therapy (group ET + S). RESULTS: Post-therapeutic or post-treatment results showed significant reduction of pain (p < 0.001) and muscle pain on palpation (p < 0.001) in patients of all groups with no significant differences between the individual groups. Mouth opening improved significantly in patients of groups ET and ET + S, but not in those in group S, who had already shown normal mouth opening in the baseline assessment. Subjective patient assessments of the individual items showed a significant improvement in all groups (p < 0.001). CONCLUSION: All treatment modalities for temporomandibular disorders evaluated in this study were shown to be effective with no statistically significant differences seen between the individual groups. However, it must be considered that the baseline findings for the patients in the group with combination therapy were inferior.

Objectives Assessment of dental material biocompatibility is gaining increasing importance for both patients and dentists. Dental cements may be in contact with oral soft tissues for prolonged periods of time and play an important role in prosthetic rehabilitation. The aim of the present study was to evaluate eight dental cements using a standardized L929-fibroblast cell culture test. Methods For each material, fresh specimens (added to the cultures immediately after preparation) and specimens preincubated for 7 days in cell culture medium were prepared according to the manufacturers’ recommendations. After exposure to test specimens, cell numbers were compared to glass controls. The main outcome was a two-sided 95% confidence interval for the mean value of the standardized cell number for each substance investigated. Results Fresh specimens of all tested cements showed significant cytotoxicity, which diminished after 7 days preincubation. Cytotoxicity of fresh adhesive and self-adhesive resin cements was lower when specimens were dual-cured compared to self-cured. A rank order of cytotoxicity was established based on mean values: Nexus 2 (dual-cured) showed least cytotoxicity, followed by Variolink II (dual-cured), Nexus 2 (self-cured), Harvard, RelyxUnicem (dual-cured), Panavia 21, Fujicem, Durelon, Variolink II (self-cured), RelyxUnicem (self-cured), Maxcem (dual-cured) and Maxcem (self-cured). When bondings were added to Nexus 2 or Variolink II specimens, a slight increase in cytotoxicity was observed. Significance Adhesive resin cements showed less cytotoxicity than self-adhesive and chemically setting cements. Bonding only slightly influenced cytotoxicity of the adhesive resin cements. Dual-cured specimens of adhesive and self-adhesive resin cements showed significantly less toxicity than self-cured specimens.

The Club of Female Professors of the Medical University Vienna (MUW) was founded in 2005 to strengthen and improve the impact of common concerns and ideas. The mission of this continuously growing club is to improve the situation of women, including colleagues, coworkers, students and patients, at the MUW. This important goal is pursued by continuous interaction with rectorate, academic senate and politicians.

The purpose of this study was to examine the differences in expert ratings of quality of magnetic resonance images (MRI) of the temporomandibular joint in 24 patients with suspected anterior disc displacement examined in randomized order at 1.5 and 3.0 T. Parasagittal (closed and opened mouth) and paracoronal sections were performed with a surface coil. Two experienced examiners blinded to patient status and type of MRI diagnosed the images according to position of condyle, position and changes in the signal, and disc shape. In addition, perceptibility of position and disc shape were assessed. A highly significant difference in the perceptibility of disc shape (P < 0.001) and position (P < 0.001) was obtained. With comparable examination sequences and identical resolution, the 3.0 T MRI of the temporomandibular joint increases the perceptibility of joint structures.

Zusammenfassung Hintergrund Patienten mit craniomandibularen Funktionsstorungen beschreiben als Hauptsymptome nicht nur Zahnschmerzen, sondern auch Gesichtsschmerzen, Beweglichkeitseinschrankungen und Spannungen im Kiefergelenk und in der Halswirbelsaule – eine interdisziplinare Uberlagerungssymptomatik (myofaszial – stomatognath – lymphogen – etc.). Eine rasche Besserung motiviert den Patienten und erleichtert weitere Therapien. Ziel Ziel dieser Studie ist es, die Sofort-Effekte von Mikrosystem-Akupunktur bei Schmerzpatienten mit Storungen im craniomandibularen System im Vergleich zu einer Kontrollgruppe zu untersuchen, wobei die subjektive Schmerzintensitat (VAS), die muskulare Funktionalitat (Druckdolenzen-Scores), die Mundoffnung, die Axiografie und vor allem die palpierten und therapierten Akupunkturareale die Hauptzielgrosen darstellen. Methodik Im Rahmen einer randomisierten, placebo-kontrollierten Studie wurden 23 Patienten mit Storungen des craniomandibularen Systems ausgewahlt und in zwei Gruppen eingeteilt. Die Verumgruppe erhielt eine Akupunkturtherapie nach der „Very Point”-Methode, die andere als Kontrollgruppe eine Placebolasertherapie. Vor und nach der Behandlung wurden bei beiden Gruppen folgende Befunde verblindet erhoben: subjektiver Schmerz (VAS), Mundoffnung in Millimeter, Druckdolenzen der Gesichts- und Nackenmuskulatur (0–3), die Druckempfindlichkeit (0–3) der Akupunkturareale (MAPS). Der Beurteiler wusste nicht, welcher Gruppe der Patient zugeteilt war, der Therapeut musste naturlich informiert sein. Ergebnisse Die Verbesserungen der muskularen Schmerzscores (Skala 0 = sehr gut – 3 = sehr schlecht) in der Akupunkturgruppe (19,1 ± 11,9) waren gegenuber der Placebogruppe (6,2 ± 14,8) signifikant (p = 0,03). Die Unterschiede der Druckdolenzen der Nacken- und Kaumuskulatur waren bei den meisten vor der Behandlung druckdolenten Muskeln in der Akupunkturgruppe signifikant (p Schlussfolgerung Aufgrund der Ergebnisse der vorliegenden Studie ist die Akupunktur ein geeignetes Mittel zur Akuttherapie bei craniomandibularen Storungen. Weitere Studien mit groserer Patientenzahl und Untersuchungen der Langzeitwirkungen sind in Arbeit.

Twenty consecutive patients suffering from myofascial pain dysfunction (MPD) were assigned to a waiting-list, serving as a no-treatment control period. Inclusion criteria were: (i) pain in the temporomandibular region for at least 3 months, (ii) no evidence of internal derangement or osteoarthritis and (iii) symptoms of postural dysfunction. Treatment consisted of active and passive jaw movement exercises, correction of body posture and relaxation techniques. The following main outcome measures were evaluated: (i) pain at rest, (ii) pain at stress, (iii) impairment, (iv) mouth opening at base-line, before and after treatment and at 6-month follow-up. All patients completed the study and no adverse effects occurred. During control period no significant changes occurred. After treatment six patients had no pain at all (chi-square: P

To evaluate the outcome of immediately loaded distally cantilevered mandibular full-arch prostheses according to the 'all-on-four' concept supported by implants placed in both fresh extraction and healed sites.A prospective study was conducted in 24 patients with extraction of all remaining mandibular teeth and placement of 4 implants per patient (2 mesial axial and 2 distal tilted) for full-arch mandibular restorations. Implants were inserted in fresh extraction sockets 2.3 ± 1.0 per patient and 1.7 ± 1.0 implants in healed sites. Implants placed in fresh extraction sites (n = 55) were significantly (P0.01) more deeply inserted than implants (n = 41) placed in healed sites (peri-implant alveolar crest: +1.6 ± 0.8 mm vs +0.6 ± 0.7 mm). Patients received an immediate provisional fixed dental prosthesis and, 3 months later, a definite resin veneered prosthesis with metal framework. At the 12-and 24-month follow-up, patients were evaluated for implants and prosthesis success, for prosthodontic maintenance efforts and patient satisfaction. At both follow-up examinations, peri-implant marginal bone level, implant pocket depth, plaque, bleeding, gingival and calculus indices were evaluated and compared between implants placed in fresh extraction and healed sites.At the 24-month follow-up, no implant failed and all prostheses were stable. There were five fractures of the provisional prosthesis in 5 patients but no fracture of the definite prostheses. For the definite prostheses, 15 acrylic teeth had to be renewed/repaired (in 10 patients) and 18 patients presented the need for the implant-supported prosthesis to be rebased. Peri-implant marginal bone level after 12 and 24 months was -0.18 ± 0.20 mm and -0.40 ± 0.29 mm for all implants (P0.001) representing bone level differences of 0.35 mm between implants placed in healed and post-extractive sites at both the 1st year (95%-CI:-0.49 to -0.20) and the 2nd year (95%-CI: -0.57 to -0.14) assessment. Plaque (1st year: 1.17 ± 0.48 versus 0.5 ± 0.6; P0.001; 2nd year: 1.21 ± 0.51 versus 0.55 ± 0.6; P0.001) and calculus indices (1st year: 0.92 ± 0.28 versus 0.45 ± 0.51; P0.001; 2nd year: 1.00 ± 0.42 versus 0.5 ± 0.51; P0.001) were significantly higher for implants placed in fresh extraction than in healed sites. Patients' subjective satisfaction score rating assessed by 5 items was high at the 1- (score: 4.6 ± 0.4) and 2-year evaluation (score: 4.7 ± 0.36).Within the limits of this study, immediately loaded full-arch prostheses can be supported by four implants placed simultaneously into healed and fresh extraction sites.

The background and purpose of this investigation was to evaluate the use of a treatment protocol which included active and passive jaw movements, manual therapy techniques, correction of body posture, and relaxation techniques for the treatment of temporomandibular joint (TMJ) osteoarthrosis (OA). Twenty consecutive patients suffering from TMJ OA participated in this study.a. pain in the temporomandibular region; b. symptoms lasting at least three months; and c. radiologically proven OA. All patients were assigned to a waiting list, serving as a no treatment control period. Nineteen patients completed the study. No adverse effects occurred. During the control period (mean duration 35 days), the parameters did not change significantly. After treatment (mean duration 46 days) pain, impairment, and incisal edge clearance improved significantly (Wilcoxon test p0.001). At follow-up, pain and impairment were further reduced. The number of patients experiencing no pain at rest (80%), chi-square test p = 0.02) and stress (47%), chi-square test p = 0.03), and no impairment (37%), chi-square test p = 0.05) increased significantly. This therapeutic treatment protocol seems to be useful treatment for the symptoms of clinical dysfunction in OA of the TMJ.

Nicolakis P, Erdogmus B, Kopf A, Djaber-Ansari A, Piehslinger E, Fialka-Moser V. Exercise therapy for craniomandibular disorders. Arch Phys Med Rehabil 2000;81:1137-42. Objective: To evaluate the use of exercise therapy for the treatment of craniomandibular disorders (CMDs). Design: Before-after trial. All patients were assigned to a waiting list, serving as a no-treatment control period. Setting: Outpatient clinic for physical medicine and rehabilitation of the University of Vienna. Patients: Thirty consecutive patients suffering from CMD with anterior disc displacement with reduction who were consulting a CMD service. Inclusion criteria: (1) symptoms lasting at least 3 months, (2) pain in the temporomandibular region, (3) a positive axiography, and (4) evidence of postural dysfunction. Twenty-six patients completed the study; no adverse effects occurred. Interventions: Active and passive jaw movement exercises, correction of body posture, and relaxation techniques. Main Outcome Measures: (1) Pain at rest, (2) pain at stress, (3) impairment, and (4) mouth opening at baseline, before and after treatment, and at 6-month follow-up. Results: During the control period, no changes occurred. After the treatment, pain and impairment were significantly reduced (Wilcoxon test, p 2 test, p 2 test, p Conclusion: Exercise therapy seems to be useful in the treatment of anterior disc displacement with reduction. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

The purpose of this research was to show that a relationship between craniomandibular disorders (CMD) and postural abnormalities has been repeatedly postulated, but still remains unproven. This study was intended to test this hypothesis. Twenty-five CMD patients (mean age 28.2 years) were compared with 25 gender and age matched controls (mean age 28.3 years) in a controlled, investigator-blinded trial. Twelve postural and ten muscle function parameters were examined. Measurements were separated into three subgroups, consisting of those variables associated with the cervical region, the trunk in the frontal plane, and the trunk in the sagittal plane. Within these subgroups, there was significantly more dysfunction in the patients, compared to control subjects (Mann-Whitney U test p0.001, p0.05, p0.01). Postural and muscle function abnormalities appeared to be more common in the CMD group. Since there is evidence of the mutual influence of posture and the craniomandibular system, control of body posture in CMD patients is recommended, especially if they do not respond to splint therapy. Whether poor posture is the reason or the result of CMD cannot be distinguished by the data presented here.

The lengths of the condylar pathways during protrusive and opening movements were investigated with computerized axiography in 100 individuals. Forty-two patients suffering from anterior disk displacement with reduction (ADD) in one or both temporomandibular joints (TMJ) and 28 patients with anterior overrotation clicking (AOC) of the TMJ were compared with 30 asymptomatic volunteers. Patients suffering from ADD showed significantly shorter tracings than did the two other groups. A significant difference of length of TMJ movement between men and women was found only in one group. The occlusal indices (OI) of the three groups were assessed and compared with each other. Here, a significant difference was found between volunteers and patients suffering ADD and between volunteers and patients with AOC. Between men and women a significant difference of the OI was found in the group with AOC, women presenting higher scores than men. Except for the group of patients with ADD, who showed shorter average lengths, volunteers as well as patients with AOC, were within the normal limits given in the literature for TMJ movement lengths recorded with axiography. The results of this examination therefore indicate that when considering movement length alone no discrimination between healthy and diseased TMJ can be made.

PURPOSE This retrospective study evaluated implant and prosthodontic survival/success rates of four-implant-supported distal cantilevered mandibular fixed prostheses over more than 5 years of clinical use. MATERIALS AND METHODS Patients with mandibular edentulism treated with four-implant mandibular prostheses with distal extensions were evaluated. Cumulative implant survival/success rates, peri-implant conditions, and prosthodontic maintenance efforts were assessed. Relationships between the degree of distal implant tilting, length of cantilevers, and implant-generated supporting zone were evaluated. RESULTS Thirty-eight patients with 152 implants (90.5% of the original sample) were available for follow-up after 5 to 7 years (mean follow-up, 66.5 ± 3.1 months). The cumulative survival and success rates for included implants were 100% and 98.6%, respectively. Denture cantilever length (mean, 14.7 ± 2.3 mm; range, 9 to 20 mm) and implant-generated supporting zone (mean, 318.9 ± 48.1 mm(2); range, 225 to 410 mm(2)) showed significant positive and negative correlations, respectively, with the inclination of tilted distal implants toward the occlusal plane (76 ± 7.2 degrees; range, 65 to 90 degrees). Peri-implant marginal bone resorption (1.5 ± 0.4 mm) and pocket depths (1.8 ± 0.8 mm) were similar for anterior and posterior implants and were not influenced by degree of tilting or cantilever length. Plaque and calculus conditions were poorer for anterior implants than for posterior implants. No dentures fractured; however, fractures of resin tooth veneer material, denture rebasing, and a strong need for cleaning as a result of resin discoloration were seen. CONCLUSION Fixed four-implant rehabilitations with distal cantilevers of a defined length with or without distally tilted implants showed high success rates. Inferior hygiene in the anterior mandible regions may be a result of reduced cleansability and variations in anatomical landmarks. Resin veneering proved advantageous for repair or modification but disadvantageous for discoloration.

The study investigated two mandibular positions based upon computerized axiography recordings of hinge axis movements of 262 subjects. Next to the well-known guided closure position RP (reference position by chin-point guidance), the position of final deglutition (FD) was quantified. FD represented the hinge axis position at the end of the swallowing movement. The results elicited average linear distances of 0.32 +/- 0.43 mm on the right and 0.33 +/- 0.40 mm on the left side between both positions in the sagittal plane. The average distance in the frontal plane was 0.02 mm (right) and 0.04 mm (left). Approximately 46 per cent of FD recordings were found anterior and inferior to RP, and showed significant difference to posterior and anterior-superior FD recordings. The replicability of both positions was tested on 53 subjects and averaged 0.04 mm (FD) and 0.09 mm (RP). Average deviations of repeated recordings within the subject ranged from 0.07 to 0.47 mm (FD) and 0.07 to 0.57 mm (RP) for each spatial direction. The results of this study showed a relative coincidence of an average FD and RP Variation of FD in anterior inferior direction questioned the clinical reliability of FD to reassure the guided closure position.

Symptoms of temporomandibular joint (TMJ) dysfunction can seriously compromise patients' quality of life. The aim of our study was to use magnetic resonance imaging (MRI) T2 mapping of the articular disc to determine whether T2 mapping of the TMJ disc is feasible in routine clinical imaging and to assess the normal T2 relaxation time distribution within the TMJ. Included were ten asymptomatic volunteers without pain, any mouth-opening limitations, or any clicking phenomena. MR imaging was performed on a 3-T MR scanner using a flexible, dedicated, eight-channel multielement coil. T2 mapping was performed in the oblique sagittal plane. The regions of interest (ROIs) for the T2 relaxation time maps of the disc were selected manually. The mean values for ROIs ranged between 22.4 and 28.8 ms, and the mean for all ROIs was 26.0 ± 5.0 ms. Intraclass correlation (ICC) for interobserver variability was 0.698, and ICC for intraobserver variability was 0.861. There was no statistically significant difference between raters (p = 0.091) or sides (p = 0.810). The T2 mapping technique enables ultrastructural analysis of the composition of TMJ disc. This biochemical technique is feasible in vivo, as shown in our study, when a high-field (3 T) MR and a dedicated TMJ coil are used. T2 mapping as a biochemical technique, together with morphological MRI, may help to gain more insights into the physiology and into the pathophysiology of the articular disc in the TMJ noninvasively and in vivo.

The effect of arbitrary mounting of maxillary casts on occlusal relationships was investigated in this study. Maxillary casts of 31 volunteers were mounted on an articulator by use of two split cast bases. This mounting was done first with the arbitrary face bow and second with a hinge bow. Three reference points were defined and measured on each maxillary cast with a three-dimensional digitizer. The measurements were taken from the arbitrarily mounted cast and from the cast mounted according to the hinge axis. Opening and closing movements that were transferred according to the hinge axis. Opening and closing movements that were transferred from the articulator to the mouth of the patient were simulated by a computer based on measurements of the reference points. The results revealed that the use of an arbitrary face bow causes a deviation of the hinge-axis points from the precise axis of more than 5 mm in 77% of the cases. Resulting occlusal errors depended on the angles between the arbitrary and precise axes and the direction of the axis shifts. The occlusal error is roughly proportional to the shift or tilting of the hinge axis in millimeters or degrees. For a given deviation of the arbitrary and precise axes, the occlusal error is proportional to the record height. For a record height of 2 mm or more, an occlusal error of more than 0.1 mm will occur. An average occlusal error of more than 0.1 mm would most likely lead to the necessity of extensive selective grinding of occlusal discrepancies in the patient's mouth.

Computerized axiography was used as an objective instrumental method of evaluating the response of patients with temporomandibular joint (TMJ) symptomatology to occlusal splint therapy. Diagnosis was performed in a standardized manner by systematically analyzing TMJ path tracings obtained by computerized axiography. Thirty-six patients were axiographed before and after therapy with full-arch occlusal stabilizing appliances, followed by assessing the effect of therapy on various path curve parameters. The data obtained for the patient group treated with splints was compared to that of six patients also axiographed, but left untreated for a period of six weeks before a second TMJ tracing was obtained. The results show that splints have a certain effect on reciprocal TMJ clicking (response rate 67%). Retral stability and path characteristics are also substantially improved (response rates 44% and 40%). Less influence was noted on hypomobile joint paths (response rate 29%), the quality of movements (response rate 28%) and Bennett angle values (response rate 23%). Patients with disk displacements without reduction were not treated with splints, they underwent surgery. Their results will be reported later. By contrast, TMJ tracings in the control group remained essentially unchanged.

To determine patient satisfaction and preference for implant-supported mandibular overdentures (IOD) retained with ball or Locator attachments. In addition, peri-implant conditions and prosthodontic maintenance efforts for the final attachments were evaluated after 1 year of function.In this crossover clinical trial, 20 edentulous patients were recruited to receive two mandibular implants in the canine region and were provided with implant-retained mandibular overdentures and new complete maxillary dentures. Implant-retained mandibular overdentures were stabilized with either ball attachments or Locator attachments, in random order. After 3 months of function, the attachments in the existing denture were changed. Questionnaires on satisfaction/complaints with the prostheses were administered at baseline (with the old dentures) and after 3 months of function with each attachment, thus providing for an intraindividual comparison. The decision for the final attachment chosen was based on the patient's preference. For the definitive attachment, peri-implant conditions (peri-implant marginal bone resorption, pocket depth, and Plaque Index, Gingival Index, and Bleeding Index) as well as prosthodontic maintenance efforts and satisfaction score were evaluated after an insertion period of 1 year.Nineteen (95%) patients completed the study (1 dropout). Patient satisfaction improved significantly (P.05) from baseline (old dentures) to the new prostheses retained with each of the two attachment types for all domains of satisfaction. However, there were no differences between ball or Locator attachment for any items of satisfaction evaluated and neither attachment had a significant patient preference. No differences for peri-implant parameters or for patient satisfaction were noted between the definitive attachments (ball, n=10; Locator, n=9) after 1 year. Although the overall incidence rate of prosthodontic maintenance did not significantly differ between both retention modalities, the Locator attachment required more postinsertion aftercare (activation of retention) than the ball anchors.

Unguided protrusive and retrusive mandibular movement was investigated in 76 asymptomatic volunteers and temporomandibular joint (TMJ) patients using computerized axiography. In 38 of these subjects, guided pro-/retrusion was also recorded. Measurements were performed in a three-dimensional Cartesian coordinate system (x = anteroposterior; y = transversal, toward the hinge axis; z = craniocaudal). Transversal shift (y) was measured and evaluated as well as the distance "s" and horizontal condylar inclination (HCl) at the point of maximum transversal deviation. The patterns of the tracings were analyzed with a view to diagnostic improvements. The objective of this study was to evaluate transversal shift and to examine the postulate of symmetrical behavior of the TMJs in pro-/retrusion. The mean mandibular shift was 0.15 mm to the left. This maximum deviation was seen in a mean distance "s" of 7.42 mm in relation to the Cartesian coordinate system in reference position. These results suggest a functional dominance of the right part of the mandible in protrusive and retrusive movement.

The objective of this series is to observe and analyze movements of the temporomandibular joint (TMJ). With the information from these studies, orthopedic standards for jaw movements will be established in further investigations according to the neutral-zero method used in general orthopedics. Any restricted range of motion can thus be defined as a deviation from these standards. Direct interpretation and objective evaluation of joint functions has major practical implications. With the aid of computerized axiography, mediotrusive movements of 48 asymptomatic volunteers and 66 jaw patients were evaluated. The movements performed were either free or guided. The mean curve lengths, as well as the Bennett angles at 3 mm and at the end point were recorded. An average group was defined, containing the values of 50% of all volunteers. The interquartile range was calculated for lengths of mediotrusive movements as well as for Bennett angles. The average range of free mediotrusive movement for female volunteers was 11.06-11.98 mm (mean 11.55 mm) on the right side and 10.47-11.75 mm (mean 11.24 mm) on the left side. Male volunteers showed an average range of 10.23-11.54 mm (mean 11.1 mm) on the right side and 10.24-11.73 mm (mean 11.12 mm) on the left side. The values for female patients amounted to 9.95-1.66 mm (mean 10.8 mm) on the right side and 9.75-11.28 mm (mean 10.55 mm) on the left side. The average range for male patients was 9.06-9.71 mm (mean 9.54 mm) on the right side and 9.17-10.23 mm (mean 9.73 mm) on the left side. The average range for Bennett angles at maximum excursion in free mediotrusive movement was between 0.41 and 5.89 degrees (mean 4.43 degrees) in the volunteers on the right side and between 2.45 and 10.07 degrees (mean 6.87 degrees), respectively, on the left side. The values for patients amounted to 0.19-12.65 degrees (mean 6.93 degrees), on the right side and 1.71-14.15 degrees (mean 6.73 degrees) on the left side.

Implant success, peri-implant conditions, and prosthodontic maintenance requirements were evaluated and compared for mandibular overdentures supported by two implants and retained with ball or resilient telescopic crown attachments during a 5-year period.Twenty-five patients with an edentulous mandible each received two root-form dental implants in the mandibular interforaminal (canine) region. The type of denture attachment was chosen randomly; 13 patients received ball attachments and 12 patients received resilient telescopic crowns. Implant success and peri-implant conditions (bone resorption, pocket depth, Plaque Index, Gingival Index, Bleeding Index) as well as prosthodontic maintenance and patient satisfaction were evaluated annually during a 5-year follow-up period and compared with respect to the two retention modalities used.Implant success, peri-implant conditions, and subjective patient satisfaction scores did not differ between the two retention modalities used. However, during the 5-year observation period, significantly more postinsertion complications/interventions for maintenance purposes were registered in the ball group (87 interventions, 61.1%) than in the telescopic crown group (53 interventions, 37.9%; P.01). Differences in prosthodontic maintenance efforts were most significant in the second and third years (P.05) of the follow-up period but were similar at the end of the study for both anchorage systems.Both ball attachments and resilient telescopic crowns on isolated implants in the atrophic mandible are viable treatment options for implant-supported overdentures. No implant losses, good peri-implant conditions, and general patient satisfaction were noted. Although the frequency of technical complications was initially higher with ball attachments than with resilient telescopic crowns over a 5-year period, similar frequencies of maintenance efforts may be anticipated for both retention modalities.

The present study evaluated implant survival/success rate, peri-implant parameters and prosthodontic maintenance efforts for four implant-supported mandibular overdentures (IOD) rigidly retained on either milled bar or double crowns (telescopic) attachments.In a randomized prospective trial, 51 patients with edentulism received four mandibular interforaminal implants and complete maxillary dentures. For IOD, rigid denture stabilization was chosen randomly selecting 26 patients for milled bars (group I) and 25 patients for double (telescopic) crowns (group II). During a 3-year follow-up period, implant survival/success, peri-implant parameters (marginal bone resorption, pocket depth, plaque-, bleeding-, gingival index [BI and GI], calculus) and prosthodontic maintenance efforts were evaluated and compared between both retention modalities used.Forty-five patients (23 group I, 22 group II) were available for a 3-year follow-up (dropout rate: 11.8%) presenting a high implant survival/success rate (100%). Peri-implant marginal bone resorption, pocket depth as well as BI and GI did not differ for both rigid retention modalities. However, annually higher values for plaque- (NS) and calculus index (P0.035) were noticed for the bar (group I) than for the telescopic crown (group II) attachments. Prevalence of prosthodontic maintenance did not differ between both retention modalities (group I: 0.41/maintenance efforts/year/patients vs. group II; 0.45 maintenance/efforts/year/patients). However, prosthodontic adaption for handling mechanism showed benefits for the bar retention.Rigid anchoring of IOD retained either by bar or telescopic attachments showed high implant success rates and minor prosthodontic maintenance efforts regardless of retention modalities used. Stable denture retention presented healthy peri-implant structure for implants in bar and telescopic anchoring systems. Drawbacks such as higher plaque/calculus for bar retention and less favorable handling properties (output) for telescopic crown attachment leave the decision on the selection at the discretion of the clinician.

The aim of this study was to evaluate soft tissue development at concave circular macro-grooved titanium abutments in healed sites.In a split-mouth pilot study 10 patients received two implants each at healed posterior sites in contralateral maxillary or mandibular jaw quadrants. Either circular macro-grooved concave study abutments or conventional convex control abutments were immediately provisionalized and received permanent crowns 3 months postimplantation. Marginal bone level, papilla index, modified plaque and bleeding index were recorded. The esthetic outcome was evaluated with standardized perpendicular pictures according to the Pink Esthetic Score (PES). Statistical analysis included the description of all variables by mean value, standard deviation and range. PES values were compared using the Wilcoxon signed rank test for paired data.Cumulative survival rate for all 20 implants was 100%. At the 1-year follow-up, there was no statistical significant difference of marginal bone levels between sites restored with the study (-0.11 ± 0.77 mm) vs. the control (-0.34 ± 0.53 mm) abutments (P0.05). Esthetic evaluation (PES) revealed statistically significant differences in scores between the study group [study abutment group] (7.2 ± 2.82, 8 ± 1.89) and the control group [control abutment group] (9.5 ± 1.58, 10.5 ± 1.72) at the time of prosthetic delivery and the 1-year follow-up. Whereas PES scores for mesial papilla at control sites at the 1-year follow-up demonstrated statistically significant higher values, both soft tissue level and soft tissue contour at control sites revealed statistically significantly higher PES values (P0.05) at time of prosthetic delivery and at 1-year follow-up when compared with study sites.Concave macro-grooved abutments in healed posterior maxillary and mandibular sites did not exhibit a superior soft tissue development compared with standard convex abutments.

The present study evaluated implant and peri-implant outcomes as well as prosthodontic maintenance efforts for implant/bar-supported mandibular prostheses with different prosthesis anchorage systems.Seventy-six patients who received two or four interforaminal implants were assigned to one of three different bar designs and subsequently to different prosthesis supporting systems. Forty-nine patients received implants and a mucosa-supported implant-retained overdenture (OD) with an ovoid bar (two implants; design 1) or multiple ovoid bars (four implants; design 2). Twenty-seven patients received four implants and a rigid implant-supported prosthesis (ISP) with a milled bar (design 3). Implant survival, peri-implant parameters (marginal bone resorption, pocket depth, and plaque, bleeding, gingival, and calculus indices), and postinsertion prosthodontic maintenance were followed over a 5-year period and compared among the different retention modalities. At the most recent follow-up examination, subjective patient satisfaction was additionally evaluated using a simplified scoring system (ranging from 1 = not satisfactory to 5 = excellent).Implant survival rates (100%) and all peri-implant parameters evaluated showed no differences among the three designs used for implant prosthesis anchorage. Prosthodontic maintenance did not differ between the different ODs (OD design 1: average of 1.04 maintenance visits/year/patient; OD design 2: 1.2 maintenance visits/year/patient), but it was significantly lower for the dentures that were rigidly stabilized with milled bars (ISP: 0.37 maintenance visits/year/patient). A high subjective satisfaction rate (range: 4.5 to 5.0) was registered at the final examination, without any differences among the designs used.Rigid anchorage with milled bars on four-implant prostheses combined with a metal-reinforced framework showed a lower extent of prosthodontic maintenance issues than round bars on two- or four-implant overdentures with resilient denture stabilization. Nevertheless, implants and peri-implant structures were not negatively affected by either resilient or rigid anchorage mechanisms.

The aim of this retrospective study was to evaluate the long-term survival and success rates of screw-type root-shaped (Camlog) implants of various diameters and their implant-prosthodontic reconstructions for more than 5 years of clinical use.A retrospective study of patients receiving root-shaped screw-type dental implants placed between May 2001 and July 2003 was conducted. The cumulative implant survival and success rates and peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index) as well as the prosthodontic maintenance requirements were evaluated.In all, 541 implants (3.8 mm: 237 implants; 4.3 mm: 211 implants, 5/6 mm: 93 implants) were placed and restored for implant prosthodontic rehabilitation in 216 patients (134 women, 82 men; mean age 54.3 +/- 9.1 years). Of the original 216 patients enrolled, 198 (91.6%; 510/541 implants [94.2%]) were available for a follow-up evaluation after 5 to 7 years (mean follow-up, 68.8 +/- 7.4 months). The overall cumulative 5-year survival and success rates were 98.3% and 97.3%, respectively. A failure rate of 3.7% (9/237) was seen for 3.8-mm-diameter implants; the corresponding figures for the 4.3-mm and wide-diameter (5.0/6.0-mm) implants were 1.4% (3/211) and 1.0% (1/93), respectively. For implants classified as successful, the average peri-implant marginal bone resorption value was 1.8 +/- 0.4 mm, with no differences among the different implant diameters evaluated. Peri-implant soft tissue conditions such as plaque, bleeding, and pocket depth were also satisfactory. All prostheses were functional throughout the observation period, with no fractures of implants, abutments, or screws. Abutment screw (4.5%) or isolated crown loosening (9.8%) for single-tooth restorations requiring recementation, retightening of screws, and adaptation of removable prostheses were the most frequent prosthodontic maintenance needs.The root-shaped implants and the associated prosthetic constructions used in this study showed excellent survival and success rates.

This retrospective study assessed implant and prosthodontic treatment outcomes of patients suffering from rheumatic disorders such as rheumatoid arthritis (RA) and connective tissue diseases (CTDs).This study included 22 patients (all women) suffering from autoimmune rheumatic disorders such as isolated RA (n = 16), RA with concomitant CTDs (n = 5), or isolated CTDs (n = 1). Overall, 89 implants were placed for rehabilitations such as single-tooth replacement (n = 8), fixed partial dentures (n = 14), complete dentures (n = 5), and overdentures (n = 2), and were evaluated after a mean of 42.6 +/- 25.2 months. The cumulative implant survival and success rates and peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index, and Calculus Index) were evaluated with a special focus on RA and CTDs. In addition, incidence and type of prosthodontic maintenance were evaluated.A high implant survival rate was noted during follow-up with a cumulative 3-year implant success rate of 96.1%. Patients with RA demonstrated acceptable marginal bone resorption (mean: 2.1 +/- 0.5 mm) and good soft tissue conditions, while CTD patients showed increased bone resorption (mean: 3.1 +/- 0.7 mm). This was especially noted in scleroderma patients, as were major peri-implant soft tissue alterations (Bleeding Index) in patients suffering from Sjogren syndrome.A high implant and prothodontic success rate can be anticipated even for patients suffering from autoimmune rheumatic disorders such as RA and CTDs. A scrupulous maintenance program that includes optimal oral hygiene could assist in ensuring stable long-term results for CTD patients with more vulnerable soft tissue conditions. Int J Prosthodont 2010;23:22-28.