The present review fully traces the historical development of therapeutic approaches to the management oftemporomandibular disorders (TMD), with emphasis on conservative prosthodontic approaches. The tremendous amount of clinical research on TMD results in universal understanding as follows: (1) TMD consists of the umbrella terms that describe several pathological conditions with similar signs and symptoms; (2) TMD is multifactorial on the basis of biopsychosocial model etiology; (3) The long-term management ofTMD should be done within the biopsychosocial mode; (4) Because each condition of TMD can expect a natural remission, reversible therapies should come first. Standardization of the methods used to measure treatment outcomes of TMDs should be strongly established in future studies.

View full abstract

Purpose: This manuscript inspects the therapeutic outcomes of pharmacological therapies, physical medicine modalities, and surgical modalities (found in published articles) that the oral surgery domain is mainly in charge of among various therapeutic modalities in temporomandibular arthrosis. It aims to determine the therapeutic modalities with conclusive evidence and also the necessary criteria for the selection of these obtained therapeutic modalities.
Method: On April 1, 2012, we electronically searched randomized controlled trials (RCTs), systematic reviews (SRs), the Cochrane Database of Systematic Reviews (Cochrane Reviews), and the meta-analysis (Meta-A) concerning pharmacological therapies, physical medicine modalities, and surgical modalities of temporomandibular arthrosis or TMD from the database of Medline and Ichushi. We next reevaluated the RCTs adopted by the selected articles about homogeneity and validity of research design.
Results: Information on pharmacological therapies, arthrocentesis, and arthroscopy was available in the Cochrane Reviews. A very large number of RCTs, SRs, and Meta-A about pharmacological therapies was available, and a lesser number offered data concerning surgical modalities.
Conclusions: The effectiveness of self-mouth opening exercises, internal use of NSAIDs, and acupuncture for temporomandibular arthrosis was revealed. In the future we expect to learn the effectiveness of the accumulation of homogeneous RCTs of temporomandibular arthrosis.

View full abstract

The management of temporomandibular disorders (TMD) is developing following the new findings of pathogenic, etiologic, and clinical research, but many questions remain. The purpose of this study was to clarify the historical change regarding psychosomatic management of TMD patients and to contribute to future direction. The scientific TMD documents for psychosomatic research and management were picked up using various search engines such as PubMed, research magazines, and books. As a result, the research papers of psychosomatic factors in the etiology of TMD and studies on the response of psychosomatic medicines are limited, and almost no high-quality research or evidence such as randomized controlled trials is available. However, many papers and books have suggested the importance of the relation between the psychosomatic factor and TMD, and further basic and clinical research is required for the psychosomatic management of TMD.

View full abstract

Purpose: In the present study, we clinically evaluated and investigated the setting of the mesiodistal width of crowns, which are important for the recovery of proximal contact of all-ceramic crowns prepared using CAD/CAM.
Methods: An all-ceramic crown preparation was performed on the lower first molar of 5 patients, and data on the shapes and positions of the abutment and adjacent teeth were collected from the master cast using the Everest®. and DECSY®. CAD/CAM systems. Crown fabrication involved the automated design of a standardized all-ceramic crown ("standard-type") and the design of an all-ceramic crown with increased mesio-distal width ("enhanced-type"), followed by ceramic block milling, polishing, and glazing. After measuring the mesiodistal width of the all-ceramic crowns, using a 3D CNC measuring system, we performed a trial insertion. Interdental separation was then measured, and a pull-out test was performed. The area of the contact points was also measured.
Results: The mesiodistal width of both the standard-type and enhanced-type crowns was stable. Interdental separation for the standard-type crown was within 50–110 µm, while the enhanced-type crown exhibited greater resistance to pull-out force than the standard-type crown. There was also no observed impact on the contact point area.
Conclusion: The present findings suggest that the mesiodistal widths of all-ceramic crowns automatically designed using CAD/CAM are within the clinically acceptable range.

View full abstract

Purpose: The objectives of this study were to determine how a change in head position while a patient undergoes dental treatment affects the condylar position, and to develop a set of standards for the patient's posture.
Methods: The condylar position was investigated in 8 subjects with normal occlusion and suffering no stomatognathic dysfunction. This was done by measuring deviation in the anteroposterior and vertical directions, and all 8 subjects attached an anterior jig. The measurement condition consisted of 4 kinds of headpositions (0 degrees, backward 10 degrees, forward 10 degrees, or forward 20 degrees from the referenceposition) while sitting and tapping on the incisal point. The measuring equipment was theexercise Gnathohexagraph®, which measures a 3-dimensional jaw with 6 degrees of freedom. The Frankfurt plane was adopted as the reference plane for Gnathohexagraph® measurement, and Beyron's point was used as the measurement point. The anteroposterior direction and the vertical direction were determined.
Results: Forward tilting of the head tended to cause a forward inclination of the condylar point, and backward tilting tended to cause backward condylar point inclination. The degree of backward mandibular inclination tended to decrease as the head was successively moved from 10 degrees backward to 0 degrees, from 10 degrees backward to 20 degrees forward.
Conclusion: It was suggested that the condylar point deviated significantly in the anteroposterior direction and the vertical direction because of changes in head positions. Consequently, it was necessary to consider the head position of the patient at the occlusal registration recording or the occlusal contact adjustment.

View full abstract

Purpose: The manufacturing process ofmouthguard sheets is either by extrusion or injection molding. The aim of this study was to investigate the thickness of mouthguard sheets after formationinrelationto the ditched mouthguard sheet and the manufacturing process of the mouthguard sheet material.
Methods: Two manufacturing processes of mouthguard sheets were compared: extrusion molding or injection molding. The sheets were formed by vacuum former being heated until they sagged 15 mm from the baseline. Thickness was measured by a measuring device at the parts fitted to the anterior teeth (labial surface and incisal edge) and the posterior teeth (buccal surface, central groove, buccal cusp, and lingualcusp). Two shapes of the sheet were compared: ordinary sheet and ditched sheet. The difference in the ratio of change of thickness, depending on the manufacturing process, and the shapes of the sheet were analyzed by two-factor ANOVA and Tukey's test.
Results: The part of the sheet fitted to the anterior teeth (labial surface and incisal edge) and to the posteriorteeth (buccal surface, central groove, and lingual cusp) of the ditched sheet on the extrusion molding was thicker than that of an ordinary sheet. It was not significant differences in the thickness by the sheet's shape on injection molding.
Conclusion: The present study suggests that the thickness of the mouthguard sheet in this study used after vacuum forming was affected by the shape of the sheet. Further, the ditched sheet could secure thickness in the parts of the anterior teeth and posterior teeth of the mouthguard sheet on the extrusion molding.

View full abstract

Purpose: A subjective evaluation has been mainly performed to determine the friction properties of denture base materials. In the present study, we used a surface friction tester in our attempts to quantify the subjective evaluation of denture base materials, such as "easiness of sliding" and "feeling of roughness" as objective data.
Methods: Three kinds of materials were used: heat curing acrylic resin, cobalt-chromium alloy, and elastic thermoplastic resin. The objective evaluation by surface friction tester and the subjective evaluation using a Visual Analogue Scale test were carried out. Dry and wet conditions were evaluated, and the surface roughness of each denture material was also measured. The obtained data were analyzed by analysis of variancefollowed by Tukey's post hoc test (α = 0.05). The Pearson coefficient between the objective evaluation by surface friction tester and surface roughness was calculated.
Results: The objective evaluation by surface friction tester revealed that thermoplastic resin showed a lower MIU value, indicating "easiness of sliding" and MMD value, indicating "feeling of roughness" under dry conditions. The wet conditions provided lower MIU and MMD values of all materials tested comparing dry conditions. A subjective evaluation showed similar results. From the correlation between data of the surface friction tester and surface roughness, it was suggested that the surface friction tester measured the surface friction properties by using many factors, similar to human sensitivities.
Conclusion: It was suggested that subjective surface friction properties could be assessed objectively by using a surface friction tester.

View full abstract

Patients: The patient was a 61-year-old male. He was treated with a fixed partial denture (FPD) supported by implants in the maxilla and in the right mandible. Using a motion-capture system, we measured masticatory ability and maximum occlusal force along wint the perioral soft tissue movement. The measurements were done before, after, and two years after implantation. For the control group, 11 adults with individual normal dentitions were analyzed.
Discussion: In this case, the values of masticatory ability and maximum occlusal force were recovered to some extent compared with the preoperative state, but not to the same extent as from the control group. Two years after implantation, these values were restored to compare equally to the control group. Asymmetric movement of the perioral soft tissue, which had been observed in the preoperative state, was decreasing in the postoperative state.
Conclusion: These results suggest that an improvement of masticatory ability may coordinate facial soft tissue movements. Evaluation of the masticatory functions may be possible by these observations.

View full abstract

Patient: The patient was a 60-year-old male having a chief complaint of esthetic dissatisfaction with maxillary anterior teeth, and he consulted a physician of prosthodontics and orthodontics. We diagnosed the case as overclosure and maxillary protrusion of the dental alveolus character. We did prosthetic restoration by mandibular removable partial denture and maxillary connected crowns that used leveling, retraction of maxillary anterior teeth, and cast metal teeth. The passing of the patient was uneventful four years after treatment.
Discussion: In each orthodontics and prosthodontics alone, treatment had a limit, and Ithought that I had difficulty in improving chief complaint. Therefore it seemed that if an interdisciplinary approach was done, a clear treatment plan could be shown and an excellent result obtained.
Conclusion: We used an interdisciplinary approach by orthodontics and prosthodontics for esthetic dissatisfaction by maxillary protrusion, and excellent results for esthetics and function were obtained.

View full abstract

Patient: A 72-year-old female patient presented to the prosthetic department of our hospital to request prosthetic planning after the extraction of a hopeless mandibular right first molar. The patient selected the removable bridge with magnetic bar attachment from several treatment options in consideration of the ease of oral care and repair, setting feeling, and the lateral and rotational stress release of abutment teeth.
Discussion: The patient was highly satisfied with the bridge. The retentive force was excellently maintained four years and nine months later. The bridge was placed in the mouth among mastication. The oral hygiene maintenance was easily maintained.
Conclusion: It was suggested that the removable bridge with magnetic bar attachment could be an option of the prosthetic treatment for dentate elderly patients to make oral care and repaires easier.

View full abstract

Patient: A 61-year-old woman presented with a chief complaint of difficulty in chewing caused by the missing of lower molars and the mobility of upper incisors. Implant-retained porcelain-fused-to-metal prostheses were fabricated for the mandibular bilateral free-end space to reestablish proper occlusal support. For the upper incisal region, teeth-retained splinted porcelain-fused-to-metal prostheses were fabricated. The patient was followed for more than 3 years after treatment, and a slight chipping of porcelain was observed in the prosthesis of the lower left second molar during the follow-up period. The chipping was treated by surface modification and polishing of the surface.
Discussion: The presence of minute cracks in the porcelain and the alteration of occlusal contacts by physiological teeth movement might both have caused the chipping of porcelain.
Conclusion: Functional problems caused by the loss of occlusal support were successfully rehabilitated using an implant-retained fixed partial denture.

View full abstract

Patient: A 54-year-old female patient presented to our clinic. She was cleft of lip and palate with edentulous maxillae and had never undergone orthodontic treatment or bone grafting. Because the denture space was inadequate, the prostheses accompanying bite raising were delivered. To evaluate changes of the stomatognathic function after prosthetic treatment, we used the surface electromyograms technique, and also the mixing ability test was assessed over a 30-week period.
Discussion: Because no differences were found between the stomatognathic function at 30 weeks or at 3 years and 1 month after delivery, the prostheses have been functioning through maintenance, and the prognosis was favorable.
Conclusion: The patient was satisfied with her new removable dentures accompanying bite raising.

View full abstract

Patient: The patient, a 52-year-old female, visited our clinic with chief complaints of aesthetic and masticatory disorders. We suggested that a root fracture of the upper right canine had been caused by an overload on the maxillary anterior teeth serving as the occlusal support. This had resulted from a decrease in the occlusal vertical dimension caused by long neglect of the edentulous lower bilateral molars. Occlusal reconstruction was done using a bite-raising denture anda temporary bridge.
Discussion: Occlusal reconstruction was done by bite-raising denture and temporary bridge for a case of the infraocclusion without occlusal support. But it is thought that periodical recall is necessary because there were few residual teeth and convalescence is uneasy.
Conclusion: Because infraocclusion with little occlusal support easily leads to occlusal collapse, aggressive treatment making use of bite raising and occlusal reconstruction is recommended for prevention.

View full abstract

Patient: The patient was a 63-year-old female with the chief complaint of missing the mandibular left first premolar. The tooth was extracted because of root fracture. She was scared of metal allergy and placed much value on visual effects. Therefore an all-ceramic fixed partial denture with zirconia framework was installed for the spaces to recover from functional and aesthetic disorders.
Discussion: An all-ceramic fixed partial denture with zirconia framework has adequate mechanical strength. Therefore it can be cemented temporarily, and the occlusion can be examined during the term of temporary cementing. After 5 years observations, no prosthetic or aesthetic complication was observed.
Conclusion: An all-ceramic fixed partial denture with zirconia framework provided satisfactory long-term functional and aesthetic results for a patient who was scared of metal allergy and had aesthetic demands with a missing posterior tooth.

View full abstract