The International Journal of Prosthodontics, 03/2019

Purpose: To assess the impact of temporomandibular disorders (TMD) on general health quality of life in a Brazilian population-based cross-sectional survey. Materials and Methods: A total of 1,643 patients were assessed using the World Health Organization Quality of Life Bref (WHOQOL-Bref) and the Research Diagnostic Criteria for Temporomandibular Disorders Axes I and II (RDC/TMD). Cross-tabulation of the data was carried out to compare TMD subjects to controls in all domains of the WHOQOL-Bref and the RDC/ TMD. Results: TMD subjects had significantly worse quality of life than controls in Axes I and II of the RDC/TMD and in all WHOQOL-Bref domains except for disc displacement. Osteoarthrosis was significantly different only in the WHOQOL-Bref physical domain. Conclusion: TMD subjects had worse general health quality of life, particularly in Axis I groups with higher pain/disability levels (muscle disorders/arthralgia/ arthritis).

Purpose: To report the feasibility of oral rehabilitation in patients who had undergone marginal mandibulectomy and to describe the factors that impact the selection of a mandibular resection prosthesis. Materials and Methods: A retrospective review of patients who had undergone marginal mandibulectomy over a 14-year period at a tertiary care cancer center was undertaken. Measurements of the vertical height and width of the mandible and the distance between the alveolar crest and mandibular canal were measured after marginal mandibulectomy. The feasibility and success of tooth-borne or implant-supported resection prostheses were measured. Results: Following marginal mandibulectomy, the median heights between the alveolar crest and lower border of the mandible were 21.8 mm, 17.7 mm, and 14.3 mm in the anterior, premolar, and molar regions, respectively. However, the median distances between the alveolar crest and the mandibular canal in the premolar and molar regions were only 3.98 and 3.4 mm, respectively. These residual bone measurements are not satisfactory for implant-supported mandibular resection prostheses, which can be considered only in the anterior region of the mandible. Patients with marginal mandibulectomy in the premolar and molar regions can only be rehabilitated with removable dentures, provided they have remaining stable teeth to clasp and anchor the removable denture. Conclusion: Implant-supported resection prostheses after marginal mandibulectomy are feasible only in the anterior segment of the mandible and are not possible in the premolar and molar regions.

Purpose: To assess the prevalence of depression and somatization in patients with temporomandibular disorders (TMD) in a Brazilian population-based cross-sectional survey. Materials and Methods: A total of 1,643 subjects were assessed for TMD using the Research Diagnostic Criteria for Temporomandibular Disorders Axes I and II and were assessed for depression and somatization using the Graded Chronic Pain Scale. The data were cross-tabulated for comparison between TMD subjects and controls. Results: TMD subjects had significantly worse depression and somatization levels than controls in the RDC/TMD Axis II. The levels were also worse in most Axis I TMD groups (muscle disorders and arthralgia/osteoarthritis/ osteoarthrosis). Conclusion: TMD subjects had worse depression and somatization, particularly in diagnostic groups with higher pain/disability levels.

Purpose: To verify whether single-implant-supported mandibular overdentures improve thickness discrimination. Materials and Methods: A selection of edentulous patients treated with single-implant- supported overdentures underwent interocclusal thickness discrimination tests using dedicated metal strips. Fifteen patients were included, and recordings were repeated five times: with complete dentures in place before placement of implants, the day of the prosthetic connection, and 1 month, 1 year, and 6 years after the connection. Results and Conclusion: Thickness discrimination improved at the 1-month recall recording, while after 1 year, it remained stable at low levels.

Purpose: To clinically evaluate the use of ceria-stabilized zirconia/alumina nanocomposite (Ce-TZP/A) for the frameworks of removable dental prostheses (RDPs). Materials and Methods: A total of 20 Ce-TZP/A RDPs (10 complete dentures and 10 implant-supported overdentures) were used in 16 patients, and the presence/ absence of complications and patient complaints were evaluated. Results: The survival rate of the RDPs during a mean follow-up period of 55.6 months was 100%, with no major complications. Conclusion: The patients experienced uneventful courses functionally and esthetically. In addition, there was no incidence of breakage or repair related to the Ce-TZP/A frameworks.

Purpose: To synthesize the evidence on the impact of treatment with conventional complete dentures (CDs) on health-related quality of life (HRQoL) and oral health-related quality of life (OHRQoL). Materials and Methods: Interventional studies were included if they evaluated the impact of CD treatment on HRQoL or OHRQoL with or without a control group. Results: A total of 22 studies were included, 10 of which had comparison groups. The results suggest that CD treatment improves OHRQoL. Conclusion: CD treatment impacts HRQoL and OHRQoL, and the Oral Health Impact Profile-EDENT is the most used instrument to measure this impact.

Purpose: To assess the current diagnostic methods for sleep bruxism (SB). Materials and Methods: This review of the literature evaluates all available instrumental and noninstrumental methods of bruxism/SB diagnosis. Results: SB diagnosis can be performed using self-reports and clinical examination, but these methods have little agreement with polysomnography. Two portable electromyography/electrocardiography appliances have been validated against polysomnography (BiteStrip and Bruxoff), but they are indicated only for primary SB. Polysomnography is considered the gold standard and is indicated for secondary SB; however, it is expensive and time-consuming. Conclusion: No perfect method of SB diagnosis exists, and future research should concentrate on improving SB self-reports.

Purpose: To systematically review the available literature and determine the potential benefits of altered cast impression technique over conventional single-impression techniques for the fabrication of distal extension removable dental prostheses. Materials and Methods: The indexed English literature published up to April 30, 2018, was systematically searched for studies comparing altered cast impression technique to conventional single-impression techniques for the fabrication of distal extension removable dental prostheses using guidelines recommended by Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA). The databases searched were PubMed, the Cochrane Library, and MEDLINE (OVID). Two reviewers independently screened and shortlisted the relevant studies based on predefined inclusion and exclusion criteria. Results: Seven studies were included in this review; all were in vivo studies. All seven studies reported that cast removable partial dentures fabricated with altered cast impression technique displayed less vertical movement of denture bases compared to those fabricated using conventional impression techniques. Two of these studies reported that this difference in vertical movement was clinically insignificant, while the other five studies reported a statistically significant difference in vertical movement but were uncertain regarding clinical significance. Conclusion: The results of this literature review indicate that the altered cast impression technique did not offer significant advantages over conventional single-impression techniques. The lack of convincing data to predict superiority of the altered cast impression technique for distal extension removable dental prosthesis impressions emphasizes the need for more scientific research with larger sample sizes and longer performance reviews of removable dental prostheses.

Purpose: To evaluate whether treatment with new complete dentures improves quality of life in elderly patients. Materials and Methods: A literature search was conducted in the MEDLINE/PubMed, Scopus, LILACS, SciELO, Web of Science, and Cochrane Library databases using specific keywords for relevant articles published up to March 2018. Three reviewers obtained the data and compared the results from reports that evaluated denture wearers 60 years of age or older whose old dentures were replaced with new ones. Results and Conclusion: Of 282 published studies, 7 met the inclusion criteria (5 evaluated quality of life before and after treatment using the Oral Health Impact Profile, 1 using the Oral Impacts by Daily Performance, and 1 using the Geriatric Oral Health Assessment Index). The articles showed a similar increase in quality of life after elderly patients were treated with new complete dentures; however, the limited methodologic quality in the reported and analyzed studies underscores the need for more robust controlled investigations to strengthen the current body of evidence, which is limited.

Purpose: To clarify the relationship between the pressure generated during impressions (impression pressure) and the presssure beneath the corresponding denture base (functional pressure) and to examine the influence of tray modifications. Materials and Methods: Impression and functional pressures were measured on models with the same appearance but different bone morphologies for comparison. Pressures with modified trays with additional relief and escape holes were also measured for comparison. Results: The correlation between impression pressure and functional pressure was high, and both could be changed by tray modifications. Conclusion: The distribution of impression pressure will be recreated beneath the denture base, and modifications of trays can control the pressure distribution.

Purpose: To investigate whether hemostatic agents have any detrimental effects on polyether impressions and plaster casts after a clinically viable cleaning protocol. Materials and Methods: A total of 60 human molar teeth were manually standardized, prepared, and subdivided into five groups (G): G0 (control/ no contamination); G1 (ViscoStat Clear); G2 (ViscoStat); G3 (Astringedent); and G4 (Astringedent X). Each tooth was contaminated with a hemostatic agent for 3 minutes and cleaned with a 30-second air/water spray. Before and after contamination, an impression was taken and a plaster cast was poured. The impressions and plaster casts of all teeth were scanned using a light scanner. Data were matched using a three-dimensional analysis software that displayed color-coded maps. Means of the maximum positive/negative values and of the mean deviations in each group were calculated and compared. All color-coded maps were interpreted descriptively using the program's color scale, and all impressions and plaster casts were microscopically evaluated. Results: Values of mean deviations throughout all matched scans showed maximum values ranging from -30.1 to +17.5 μm. None of the groups showed significantly different deviation values or patterns when compared to each other. Impressions showed a thin, discontinuous coating for G2, G3, and G4; no changes were found for plaster casts. Conclusion: Presented deviations showed the same values and distribution patterns within all groups. A cleaning protocol of 30 seconds of air/water spray is sufficient to remove hemostatic agents, preventing effects to polyether impressions and plaster casts. However, ferric sulfate-containing hemostatic agents left discontinuous coatings on impression surfaces.

Purpose: To evaluate the precision and trueness of computerized optical impressions of maxillectomy defects. Materials and Methods: Three different maxillectomy defect models based on the Aramany classification system were used. Reference digitization of the models was performed with an industrial computerized tomography scanner. Each model was scanned five times using an intraoral scanner (True Definition). With the use of 3D evaluation software, the 3D datasets were geometrically superimposed using a best-fit algorithm to evaluate precision and trueness. Statistical analysis was performed to determine differences between the scans. Results: There was a statistically significant difference in both precision and trueness between Aramany classes (P .001). Conclusion: Digitizing maxillectomy defect models with an intraoral scanner appears to be accurate and reliable.

Purpose: To geometrically evaluate facial asymmetry in patients with mandibulectomy defects with and without their mandibular prostheses in place and to compare the results to a nonpatient group. Materials and Methods: Facial data from a convenience sample of 16 patients with mandibulectomy defects and a control group of 16 nonpatients were acquired using a noncontact 3D digitizer. Facial asymmetry was evaluated by superimposing a facial scan onto its mirror scan for each patient's 3D dataset using 3D evaluation software. Results: Facial asymmetry was significantly different between mandibulectomy patients and control participants. As expected, asymmetry was significantly different in mandibulectomy patients with and without their prostheses. Conclusion: Wearing a mandibular prosthesis notably improved facial asymmetry.