Influence of occlusal appliances on the masticatory muscle function in individuals with sleep bruxism: A systematic review and meta-analysis.

This systematic review answers the question: "Does occlusal appliance use influence masticatory muscle function of dentate individuals with sleep bruxism?". The literature search included six databases, grey literature, and manual search for articles. Randomized and non-randomized clinical trials were included comparing muscle function of sleep bruxers before and after receiving occlusal appliances. Risk of bias was assessed with risk of bias assessment for randomized and non-randomized clinical trials tool. Twelve studies, three represent randomized clinical trials, were included. Risk of bias was considered low, moderate, or serious. Meta-analyses indicated that soft and hard appliances did not influence muscle activity and bite force of bruxers. Qualitative analysis showed that occlusal appliance use did not influence masticatory performance and muscle volume. However, it was effective in reducing tongue force. Certainty of evidence was considered very low for muscle activity when evaluated with hard appliances, and for bite force evaluated with both appliance materials. Low certainty of evidence was observed for muscle activity with soft appliances. Based on the findings of this meta-analysis, occlusal appliances do not affect masticatory muscle function of sleep bruxers. Regardless of appliance material, the activity of masseter and temporal, and bite force of sleep bruxers was not influenced.

Does occlusal morphology of artificial teeth improve chewing of removable dentures wearers? A systematic review and meta-analysis.

PURPOSE: This systematic review aimed to verify whether anatomic, semi-anatomic, or nonanatomic occlusal morphology of artificial teeth improves the masticatory function of complete or removable partial denture wearers. MATERIALS AND METHODS: According to the PICO strategy, six databases and the grey literature were searched to identify randomized (RCT) and non-randomized clinical trials (N-RCT) comparing masticatory function, in terms of masticatory performance and efficiency, and muscle activity as primary outcomes; and patient-reported results (O) in individuals using removable dentures (P) with different occlusal morphologies of artificial teeth (I/C). Masticatory ability, satisfaction with the prosthetic treatment, and oral health-related quality of life (OHRQoL) were evaluated as secondary outcomes. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB 2.0) for RCT and Risk of Bias for non-randomized studies with intervention (ROBINS-I) for N-RCT studies. Meta-analyses were performed to compare primary outcomes and masticatory ability between the occlusal morphologies of artificial teeth of complete or removable partial dentures (α = 0.05). Certainty of the evidence was verified using the GRADE approach. RESULTS: Eleven studies (seven RCTs and four N-RCTs) were included. The risk of bias was considered low for two studies, some concerns for five, and high for the last four studies. Meta-analyses showed that removable partial dentures with anatomic artificial teeth improved masticatory efficiency for carrot chewing (MD 6.31; 95% CI [3.39, 9.22], I2 = 0%). However, masseter and temporal muscle activities increased when removable partial dentures with nonanatomic teeth were used (MD -756.97; 95% CI [-892.25, -621.68], I2 = 100%). Masticatory ability was not influenced by occlusal morphology during chewing of all foods in complete denture users: Carrot (MD -0.88, 95% CI [-8.98, 7.23], I2 = 57%); sausage (MD -8.86, 95% CI [-23.05, 5.33], I2 = 71%); apple (MD -5.78, 95% CI [-28.82, 17.26], I2 = 87%); and cheese (MD -4.16, 95% CI [-15.14, 6.82], I2 = 62%). The certainty of evidence for all evaluated outcomes was very low, mainly due to very serious problems found in the parameters of inconsistency, indirectness, and imprecision. CONCLUSIONS: Despite the very low certainty of evidence, the occlusal morphology of artificial teeth influences masticatory function. Anatomic teeth improved the masticatory efficiency and muscle activity of removable partial denture wearers. Nonanatomic teeth increased temporal and masseter muscle activity, which negatively affected chewing in removable partial denture users. However, patients using complete dentures with anatomic and semi-anatomic teeth presented similar masticatory ability.

Funding assistance and global productivity in the field of implant overdentures: A bibliometric analysis of 35 years.

STATEMENT OF PROBLEM: Implant overdentures have been widely used as a treatment option for edentulous patients. However, the development of implants, aside from commercial growth, requires funding assistance to determine scientific reliability and clinical applications. Nonetheless, bibliometric studies in the implant overdenture field are lacking. PURPOSE: The purpose of this bibliometric analysis was to evaluate the prevalence of funding and its bibliometric associated parameters according to the financial assistance granted and the implant overdenture documentation over time. MATERIAL AND METHODS: Six databases were assessed, and 12 bibliometric parameters related to the economy, geographical origin, publication details, and corresponding author metrics were recorded. An incidence rate ratio was applied by using a multiple Poisson regression model (α=.05) to assess the association between funding and each bibliometric parameter. RESULTS: In total, 1369 studies published between 1986 and 2021 were assessed bibliometrically. The prevalence of funded studies was 34.8% (n=477). The parameter associated with the presence of funding was country income (P<.01), with those having a high and upper-middle income being more funded than those with a lower-middle and low income. Oceania and South America were the continents more frequently funded (P<.05), with Africa being the least frequent. Randomized and nonrandomized controlled trials, in vitro studies, and in silico studies were more funded (P<.001) than case reports and series. Stud and ball attachment systems were more funded (P<.01) than studies with more than 1 retention system. Funding increased over time (P<.01), and corresponding authors with a higher h-index had more studies funded (P<.05). CONCLUSIONS: The number of funded studies on implant overdentures increased over the years. Other bibliometric parameters such as country income, continent, study design, retention system, and corresponding author h-index were associated with the frequency of funded studies published.

Influence of different presentations of denture adhesives on masticatory function of complete denture wearers: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Denture adhesives improve the mastication of complete denture wearers. However, the impact of denture adhesives with different presentations on mastication remains unclear. PURPOSE: The purpose of this systematic review was to answer the focused question, "Do different presentations of denture adhesives affect the masticatory function of complete denture wearers?". MATERIAL AND METHODS: This review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Six databases and the non-peer-reviewed literature were searched up to July 2021. Only clinical studies (randomized clinical trials and nonrandomized clinical trials) comparing the use of different denture adhesive presentations (cream, powder, or strips) were included, without language or follow-up restrictions. The risk of bias was assessed by using the Cochrane tools (RoB 2.0 and ROBINS-I). Masticatory performance, by using single and multiple sieves, masticatory performance with color-changing chewing gum (mixing ability), swallowing threshold (particle size and number of cycles), jaw kinematics, and occlusal force were considered. Meta-analyses were conducted to evaluate masticatory performance (single sieve) and occlusal force outcomes (α=.05), and the certainty of the evidence was determined with the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) evaluations. RESULTS: Nine studies (6 randomized and 3 nonrandomized clinical trials) were included. The risk of bias was considered moderate. Meta-analyses showed no differences between cream and powder denture adhesives for masticatory performance (standard mean difference=0.02; 95% CI=-0.46 to 0.50, P=.93) or between cream and strip denture adhesives for occlusal force (mean difference=14.35; 95% CI=-11.14 to 39.84, P=.27). Similarly, in qualitative analysis, cream and powder denture adhesives' performances were similar regarding masticatory performance with color-changing chewing gum (mixing ability), occlusal force, swallowing threshold (particle size and number of cycles), and jaw kinematics (P>.05). However, for resorbed ridges, cream denture adhesive resulted in a higher masticatory performance than strip (P<.05). When comparing powder to strip denture adhesives, the occlusal force was higher in the powder group (P<.05). The certainty of evidence was very low for all evaluated outcomes. CONCLUSIONS: Different presentations of denture adhesives seem to improve the masticatory function of complete denture wearers in a similar way. However, the qualitative analysis showed that, in patients with a resorbed ridge, a cream denture adhesive may be better than strips to improve mastication, although the certainty of evidence was very low.

Speech in implant-supported and removable complete denture wearers: A systematic review.

STATEMENT OF PROBLEM: Prosthetic rehabilitation, especially with removable complete dentures (CDs), can contribute to speech problems, although the prevalence of the problem is unclear. PURPOSE: The purpose of this systematic review was to examine the influence of implant-supported fixed complete dentures (FCDs), implant-supported overdentures, and removable CDs on speech articulation disorders in patients with at least 1 completely edentulous jaw. MATERIAL AND METHODS: This study was prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in the International Prospective Register of Systematic Reviews (CRD42020182705). The PubMed/Medline, Embase, Web of Science, Scopus, Latin American and Caribbean Health Sciences, Brazilian Clinical Trials Registry, and Cochrane Library databases were searched through April 2020 to identify clinical trials comparing maxillary and/or mandibular implant-supported dentures with removable CD use in terms of speech articulation in participants with at least 1 completely edentulous jaw. The risk of bias of selected studies was assessed with the Joanna Briggs Institute critical appraisal tools, and the quality of evidence was tested by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: Initially, 2586 articles were identified, and their titles and abstracts were read. Sixteen articles were read in full, and 8 studies (4 paired clinical trials and 4 cross-sectional studies) were included in this review. In total, 290 prosthesis users aged 29 to 90 years, approximately 44 of whom had hearing difficulties, were included. Four studies had a low risk of bias, and 4 studies had a high risk of bias. Distortions of the /s/ phoneme were observed more often in the first 6 months of maxillary FCD use than with removable CD use. Speech articulation did not differ between mandibular FCD and removable CD users. The quality of evidence for speech articulation disorders was low. CONCLUSIONS: Given the low quality of evidence on speech articulation disorders, further research on speech articulation disorders in prosthesis wearers is needed.

Clinical performance of polymer frameworks in dental prostheses: A systematic review.

STATEMENT OF PROBLEM: High-performance polymers including polyetheretherketone (PEEK) and polyetherketoneketone (PEKK) have been used as substitutes for metal frameworks in dental prostheses. However, the clinical performance of polymer-based frameworks is still uncertain. PURPOSE: The purpose of this systematic review was to compare the clinical performance of PEEK and PEKK with that of metal frameworks for different dental prostheses. MATERIAL AND METHODS: This review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Six databases and non-peer-reviewed literature (without language or follow-up restrictions) were searched for studies conducted before February 2022. Only clinical studies, either randomized clinical trials (RCTs) or nonrandomized clinical trials (N-RCTs), comparing the clinical performance of polymer and metal frameworks were included. The risk of bias and certainty of the evidence were assessed with the RoB 2.0, ROBINS-I, and GRADE. Biologic (plaque and gingival indices, probing depth, bleeding scores, implant stability quotient, marginal bone loss) and mechanical outcomes (ridge base relation, prosthetic marginal gap, and fracture) were assessed. RESULTS: Only 9 studies (7 RCTs and 2 N-RCTs) were included, all with moderate to serious risk of bias and low to very low certainty of evidence. No meta-analysis was possible, but qualitative analysis revealed lower plaque and gingival indices, probing depth, and marginal bone loss, with higher survival rates for implant-supported fixed prostheses and overdentures fabricated with PEEK than for metal frameworks. No significant differences were found between groups for removable partial dentures. The marginal fit of PEEK frameworks was also better for single crowns. Three fractures were reported in the 3 PEKK fixed dental prostheses with cantilevers. CONCLUSIONS: PEEK and PEKK seem to be promising materials for dental prostheses, with acceptable response from the periodontal tissue. However, further well-designed studies are necessary to better understand their clinical and long-term limitations.

Bibliometric assessment in implant-retained overdenture articles: Mapping citation and journal impact factor trends.

STATEMENT OF PROBLEM: Implant-retained overdentures are a recognized treatment option. However, a comprehensive assessment of all articles on implant-retained overdentures to identify publication standards such as mean citation and the Journal Citation Reports (JCR) impact factor is lacking. PURPOSE: The purpose of this bibliometric assessment was to evaluate the association of mean citation and JCR impact factor with bibliometric parameters in articles on implant-retained overdentures. MATERIAL AND METHODS: Articles reporting randomized controlled clinical trials (RCTs) and nonrandomized controlled clinical trials (N-RCTs); case reports and series; retrospective studies; and in silico, in vitro, or systematic reviews in 6 databases were included. Data were extracted, and 2 multiple Poisson regressions analyses were applied (α=.05). The dependent variables were mean citation and JCR impact factor, which were evaluated to identify their association with bibliometric parameters by using prevalence ratio (PR) values. RESULTS: A total of 1369 articles published from 1986 to 2021 were included. The data revealed a high mean citation and high JCR impact factor for RCT, N-RCT, retrospective, and in vitro studies (P<.05). In silico studies presented a high mean citation (P<.001). Senior researchers with a high h-index were more likely to have a high mean citation and publications with a high JCR impact factor (P<.001). Also, senior authors associated with an international network were more likely to have a high mean citation (P=.001). High-income countries had more studies with a high mean citation and JCR impact factor (P<.05). Higher JCR impact factors were associated with articles evaluating only the maxilla or mandible (P<.05). The topics "implant setting" and "macrodesign" were associated with a high mean citation (P<.05). CONCLUSIONS: The publication trends suggest a high mean citation and a high JCR impact factor for clinical designs (RCT, N-RCT, retrospective) and in vitro studies. The same pattern was also displayed for researchers with a high h-index and located in high-income countries.

Palatal coverage and oral stereognosis: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Complete denture wearers present with less sensory function than dentate individuals because of the loss of periodontal receptors. However, the role of the palatal receptors on such function is still unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the influence of palatal coverage associated with complete dentures or palatal devices on oral stereognosis in edentulous or dentate adults. MATERIAL AND METHODS: Eight major literature databases and the nonpeer-reviewed literature were searched up to December of 2021. Randomized clinical trials and nonrandomized clinical trials comparing oral stereognosis in edentulous or dentate participants using conventional complete dentures or implant-supported prostheses or those using palatal devices were included. Bias was assessed with Cochrane tools (ROBINS-I and RoB 2.0). Meta-analyses were conducted to compare oral stereognosis before and after palatal coverage (α=.05). Certainty of the evidence was verified using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Of 14 included studies, the risk of bias was considered low for 9 studies and moderate for 5 studies. Despite the very low certainty of evidence, meta-analyses showed no differences in oral stereognosis immediately after complete denture insertion (standardized mean difference [SMD]=0.302; 95% confidence interval [CI]: -0.124, 0.728; P=.165; I2=92.4%). Oral stereognosis scores improved after ≥1 month of complete denture use compared with initial evaluations without them. Qualitative analysis indicated that oral stereognosis was not influenced by palatal coverage shortly after complete denture installation and that oral stereognosis scores improved over time after prosthesis use. CONCLUSIONS: Oral stereognosis improved with the use of palate-covering prostheses over time. However, because of the very low certainty of evidence, the statement must be interpreted with caution.

Prosthetic rehabilitation status, dental prosthesis functionality and masticatory function in nursing home residents.

OBJECTIVE: To evaluate the association of masticatory function with prosthetic rehabilitation status and dental prosthesis functionality in nursing home residents. BACKGROUND: Prosthetic rehabilitation status and dental prosthesis functionality may adversely affect mastication of older people, and this relationship is underestimated in nursing home residents. MATERIALS AND METHODS: This cross-sectional study included 179 nursing home residents who used dental prostheses [mean (SD) age: 78.9 (9.0) years]. Masticatory function data were determined by assessing (a) masticatory performance using two-colour chewing gum, and (b) swallowing thresholds by counting the number of peanut chewing cycles. Older adults were categorised as: (1) using dental prostheses in both jaws (n = 100) and (2) partially dentate using removable partial dental prostheses (RPDPs) or complete dentures (CDs) in only one jaw (n = 41), or (3) edentulous using CD in only one jaw (n = 38). Stability, retention, occlusion, vertical dimension and defects were considered in assessing dental prosthesis functionality. RESULTS: Greater variance of hue (VOH) of the chewing gum and lower swallowing thresholds (worse masticatory function) was associated with edentulous using CD in only one jaw. Older adults wearing dental prostheses with poor occlusion and vertical dimensions presented worse masticatory function. Dental prosthesis stability was associated with lower VOH values. Higher number of chewing cycles while eating peanuts was associated with non-broken dental prosthesis use. CONCLUSION: Edentulous participants using CD in only one jaw and non-functional dental prosthesis use negatively affect the masticatory function of nursing home residents.

Speech and the swallowing threshold in single implant overdenture wearers: A paired control study.

BACKGROUND: Single implant mandibular overdentures (SIMOs) can improve mastication in edentulous elderly people. However, little attention has been paid to their effects on articulation disorders and the swallowing threshold relative to those of conventional complete dentures (CDs). OBJECTIVE: To compare the effects of new conventional CD set and SIMOs on articulation disorders, mandibular movements during speech and swallowing threshold using a paired study design. METHODS: Twenty-two edentulous Brazilian Portuguese-speaking elderly people (mean age 66.7 ± 4.6 years) were first evaluated whilst wearing their old conventional CDs. Articulation disorders were analysed by audio and video recordings, mandibular movements during speech were measured by kinesiography, and the swallowing threshold was assessed by masticatory cycle counting and medium particle size (X50 ) calculation. Participants then received new conventional CDs, and evaluations were repeated 2 months later. Subsequently, single implants were installed in the midlines of subjects' mandibles, and the conventional CDs were converted to SIMOs. After 2 months of SIMOs use, the evaluations were repeated. Data were submitted to the Cochran-Mantel-Haenszel and ANOVA. RESULTS: No difference in articulation disorders was found between new conventional CD and SIMO use. The frequency of anterior lisp during /s/ and /z/ phoneme pronunciation was reduced with new conventional CD use relative to old conventional CD use (p < .05). The X50 decreased progressively with new conventional CD and SIMO use (both p < .05). CONCLUSION: SIMOs do not alter speech relative to new well-fitted conventional CDs, but improved the swallowing threshold, in edentulous elderly people.

Masticatory function in nursing home residents: Correlation with the nutritional status and oral health-related quality of life.

BACKGROUND: Masticatory function of institutionalised elders and its relationship with nutrition and oral health-related quality of life (OHRQoL) are unknown. OBJECTIVES: This multicentre cross-sectional study evaluated the influence of the presence of teeth and dentures on masticatory function (masticatory performance and swallowing threshold) in institutionalised elders. Correlation of masticatory function with nutrition and OHRQoL was also verified. METHODS: Older adults (n = 344; mean age (SD) = 77.70 (9.10)), selected from nursing homes in two Brazilian cities, were classified as edentulous with or without complete dentures (CDs), and partially dentate with or without prosthesis. Masticatory performance was assessed using a two-colour chewing gum. Swallowing threshold was set by the number of chewing cycles performed until swallowing 3.7 g of peanuts. Nutrition was screened by Mini-Nutritional Assessment-Short Form and body composition. OHRQoL was evaluated through Geriatric Oral Health Assessment Index (GOHAI) and Oral Health Impact Profile (OHIP-14). The Kruskal-Wallis test and Spearman's correlation were used (α = 0.05). RESULTS: Edentulous elders without CDs had lower masticatory performance than those with CDs and partially dentate with or without prosthesis (P < .05). Swallowing threshold of edentulous elders with CDs and partially dentate with prosthesis was greater than edentulous elders without CDs and partially dentate without prosthesis (P < .05). Masticatory function was not correlated with nutrition. Masticatory performance was correlated (P < .05) with GOHAI (r2  = -.154) and swallowing threshold with GOHAI (r2  = .162) and OHIP-14 (r2  = -.146). CONCLUSION: The absence of teeth and dentures negatively affected the masticatory function. Although the masticatory function was not correlated with institutionalised elders' nutrition, their OHRQoL was negatively impacted.

Association of sleep bruxism with oral health-related quality of life and sleep quality.

OBJECTIVES: To compare the oral health-related quality of life (OHRQoL) and sleep quality of subjects with and without sleep bruxism (SB). MATERIALS AND METHODS: Participants of both genders were assigned as bruxers (n = 30, age 21-45 years) and non-bruxers (n = 30, age 24-40 years). SB was clinically diagnosed and confirmed with an electromyography/electrocardiograph portable device (Bruxoff). The OHRQoL was assessed using the Oral Health Impact Profile (OHIP-14). The sleep quality was determined using the Pittsburg Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) questionnaires. OHIP-14, PSQI, and ESS data were analyzed by one-way ANOVA, considering a significance level of 5%. RESULTS: Bruxers had worse OHRQoL (mean = 16.43) than controls (mean = 4.1), with an effect size (ES) of 1.58. Moreover, SB volunteers showed the highest PSQI scores (mean = 7.07; ES = 0.82) and excessive daytime sleepiness (mean = 10.33; ES = 0.65), compared to non-bruxers (means = 4.7 and 7.8, respectively). CONCLUSIONS: SB may be associated with a negative impact on OHRQoL and sleep quality. CLINICAL RELEVANCE: Determining that SB may have a marked role in OHRQoL and sleep quality is important for dental professionals establish proper multifactorial management, and understand patient-related psychosocial aspects.

Influence of lower complete denture use on masseter muscles and masticatory function: A longitudinal study.

BACKGROUND: Edentulism can reduce mastication, leading to changes in food pattern, with possible consequences to masticatory muscle thickness. OBJECTIVES: This study verified masticatory function and oral perception in subjects who did not use lower CDs, and whether the insertion of new upper and lower CDs would improve such variables. METHODS: Fifteen edentulous elderly who wore only the upper CD were selected and received new upper and lower CD. Volunteers were evaluated at baseline and after 1, 3 and 6 months of new prosthesis use. Masticatory performance (MP) was assessed by the sieving method (X50 values). Masseter thickness (MT) was evaluated by ultrasonography. Oral sensorial ability (OSA) was assessed by oral stereognosis test and maximum tongue pressure (MTP) was verified by pressure sensors. Data were submitted to repeated measures ANOVA and Tukey-Kramer posthoc tests (α = 0.05). Correlation between OSA and MTP was verified by Person's correlation. RESULTS: X50 and MTP decreased (P < 0.05) after 1 month and remained stable (P > 0.05) for next assessments. After 3 months, MT in rest position was increased (P < 0.05), while during maximum voluntary contraction 1 month was enough to increase MT (P < 0.05). There were no differences for OSA (P > 0.05) and no correlation between OSA and MTP. CONCLUSION: Masticatory performance and masseter thickness of elderly who did not use the lower dentures were improved after 2 months using new upper and lower CDs. However, new CDs in both dental arch decreased MTP. Brazilian Registry of Clinical Trials (ReBEC #RBR-37gdst).

Long-term survival analysis of standard-length and short implants with multifunctional abutments.

BACKGROUND: Spherical shape and connecting bypass screw of the OT Equator abutment (Rhein83, Italy) provides several retentive possibilities, even in non-parallel implants. OBJECTIVE: This study assessed the long-term survival of standard-length and short implants receiving this multifunctional abutment. METHODS: Partially, edentulous patients (44 males and 64 females) (mean age 58.2 ± 10.5 years) rehabilitated with a fixed implant-supported prosthesis where the OT Equator abutments (Rhein83) were applied. Follow-up evaluations were performed up to 5 years following prosthesis delivery. Kaplan-Meier survival analysis and Cox regression analysis were used to determine whether the distribution of time to failure differed based on implant characteristics (length and region), adjusting for sex (α = 0.05). RESULTS: In total, 216 implants (5 × 8 mm, n = 126; 5 × 6 mm, n = 90) (Betwice, Mech & Human, Italy) were installed. The average follow-up period was 25.3 months (±19.3 months). Eight failures occurred, with most observed before loading (n = 6). Cumulative survival rates (CSR) at implant and abutment levels were 94.3% and 97.1%, respectively. Regarding implant length, CSRs were 97.8% and 90.6% for short and standard-length implants, respectively, with no difference between subgroups (logrank: χ2  = 1.34, df = 1, P = 0.25). No significant difference was also found between implants of maxilla (CSR = 92.2%) and mandible (CSR = 95.5%; logrank: χ2  = 0.08, df = 1, P = 0.78). CONCLUSION: The OT Equator abutment (Rhein83) showed a stable clinical performance, with continuous and predictable survival.

Reinforcement of Single Implant-Retained Mandibular Overdenture with a Cobalt-Chromium Framework before Implant Surgery.

Previous clinical research has shown promising results in oral rehabilitation of elderly adults by a single implant-retained mandibular overdenture; however, the high incidence of fracture in the anterior region of these overdentures is a concern for clinicians. To minimize catastrophic overdenture fracture, we propose a technique to insert an individualized metal framework in single implant-retained overdentures prior to implant surgery.

Parkinson's disease impairs masticatory function.

OBJECTIVE: To evaluate masticatory function in individuals with Parkinson's disease (PD) during levodopa "on" period using new removable dental prosthesis. MATERIALS AND METHODS: A total of 34 elderly individuals with PD (n = 17, mean age = 69.41 ± 4.65 years) or without PD (n = 17, mean age = 70.71 ± 4.65 years) were recruited for this study. Participants received new complete dentures and/or removable partial dentures. Two months after the subjects were free of any prostheses discomfort, masticatory function was assessed. A kinesiographic device was used to measure the range of jaw motion and jaw movements while chewing a silicone test material (Optocal). Masticatory performance was determined by median particle size (X50) of the Optocal after 40 masticatory cycles. Maximum bite force was assessed by a strain sensor placed in the bilateral first molars region. Data were analyzed by t test (P < 0.05). RESULTS: The PD group showed a decreased range of jaw motion, longer duration and slower velocity of the masticatory cycle (P < 0.05), higher X50 value, and lower maximum bite force (P < 0.05). CONCLUSION: PD patients have impaired masticatory function during levodopa "on" periods compared to controls. CLINICAL RELEVANCE: Knowledge that PD is associated with impaired masticatory function is important to dental professionals in decision making related to prosthetics and general dental treatment.

Correlation of cognitive and masticatory function in Alzheimer's disease.

OBJECTIVES: This study investigated chewing function in elderly individuals with Alzheimer's disease (AD) and correlated chewing function with cognitive status. MATERIALS AND METHODS: Sixteen elderly individuals with mild AD (mean age 76.7 ± 6.3 years; 8 men, 8 women) and 16 age and gender-matched healthy controls (mean age 75.23 ± 4.4 years; 8 men, 8 women) were included in this study. All volunteers wore removable prostheses: 11 were totally edentulous and five were partially edentulous in each group. Chewing function was evaluated via masticatory performance (MP) using Optocal chewable test material and a sieve fractionation method. Cognitive functioning was assessed by the Mini Mental State Exam (MMSE), administered by a trained examiner. Data were analyzed by non-paired t test and Pearson's correlation with α = 0.05. RESULTS: Compared to controls, mild AD patients had decreased MP (P < 0.01) and MMSE (P = 0.01). MP showed a moderate negative correlation with MMSE (r = -0.69). CONCLUSIONS: Mild AD was associated with impaired chewing function. CLINICAL RELEVANCE: Knowledge that mild AD has an impact on chewing is important for dental professionals in decision-making related to prosthetics and general dental treatment.

Influence of a removable prosthesis on oral health-related quality of life and mastication in elders with Parkinson disease.

STATEMENT OF PROBLEM: Parkinson disease (PD) symptoms, such as muscle rigidity, tremors in the lips and tongue, and involuntary mandibular movements, may cause oral health-related problems, mastication difficulties, and denture discomfort because of the difficulty in controlling a prosthesis with the oral musculature. PURPOSE: The purpose of this observational clinical study was to evaluate the influence of oral rehabilitation with a removable prosthesis on oral health-related quality of life (OHRQoL) and masticatory efficiency (ME) in elders with PD. MATERIAL AND METHODS: Thirty-four elders with PD (n=17, mean age 69.4 ±4.7 years) or without PD (n=17, mean age 70.7 ±4.7 years) were recruited. All participants first underwent OHRQoL and ME evaluations. Two months after the insertion of new removable prostheses, the participants were reassessed. The OHRQoL was measured with the Oral Health Impact Profile (OHIP-49). ME was evaluated by determining the percentage weight of the comminuted silicone-based artificial material that passed through a 2.8 mm sieve. For each group, data were compared between baseline and after insertion of new removable prostheses by paired t test or Wilcoxon sign test/signed-rank test. Group differences were assessed at each time point by t test (α=.05). RESULTS: After the insertion of removable prostheses, elders with PD showed improved OHRQoL and ME. Controls also showed improvements on both measures after insertion of removable prostheses. At baseline, elders with PD had lower OHRQoL and ME compared with the controls (P<.05). After removable prosthesis insertion, the elders with PD continued to show lower ME values than the controls, but their OHRQoL was similar. CONCLUSIONS: Oral rehabilitation with new removable dental prostheses improved the OHRQoL and ME in elders with and without PD, although ME did not reach control levels in elders with PD.

Implant retainers for free-end removable partial dentures affect mastication and nutrient intake.

OBJECTIVES: This study measured swallowing threshold parameters and nutrient intake in partially dentate subjects rehabilitated by conventional free-end removable partial dentures (RPD) and by RPD over posterior implant retainers and ball attachments (BA). MATERIALS AND METHODS: Eight subjects (two men and six women; mean age 60.1 ± 6.6 years old) received conventional total maxillary dentures and free-end RPD in the mandible. Two months after denture insertion, swallowing threshold and nutrient intake assessments occurred, which included an evaluation of the number of masticatory cycles and medium particle size (X50) of a silicone test material (Optocal). A 3-day food diary verified nutrient intake based on a standard Brazilian Food Composition Table. Then, osseointegrated implants were placed bilaterally in the mandibular first molar region, followed by BA, which was fitted in the RPD bases after healing. After 2 months of the RPD over implants and BA use, variables were again assessed. Wilcoxon signed rank tests evaluated the data (P < 0.05). RESULTS: Masticatory cycles did not differ (P > 0.05); however, subjects showed decreased X50 values at the swallowing moment (P = 0.008) and increased daily energy (P = 0.008), carbohydrate (P = 0.016), protein (P = 0.023), calcium (P = 0.008), fiber (P = 0.016), and iron (P = 0.016) intake with RPD implants and BA inserts. No differences were found in fat consumption (P > 0.05). CONCLUSION: Implants and BA retainers over a free-end RPD resulted in smaller swallowed median particle size and improved nutrient intake.

Mastication movements and sleep quality of patients with myofascial pain: occlusal device therapy improvements.

STATEMENT OF PROBLEM: Patients with myofascial pain experience impaired mastication, which might also interfere with their sleep quality. PURPOSE: The purpose of this study was to evaluate the jaw motion and sleep quality of patients with myofascial pain and the impact of a stabilization device therapy on both parameters. MATERIAL AND METHODS: Fifty women diagnosed with myofascial pain by the Research Diagnostic Criteria were enrolled. Pain levels (visual analog scale), jaw movements (kinesiography), and sleep quality (Epworth Sleepiness Scale; Pittsburgh Sleep Quality Index) were evaluated before (control) and after stabilization device use. Range of motion (maximum opening, right and left excursions, and protrusion) and masticatory movements during Optosil mastication (opening, closing, and total cycle time; opening and closing angles; and maximum velocity) also were evaluated. Repeated-measures analysis of variance in a generalized linear mixed models procedure was used for statistical analysis (α=.05). RESULTS: At baseline, participants with myofascial pain showed a reduced range of jaw motion and poorer sleep quality. Treatment with a stabilization device reduced pain (P<.001) and increased both mouth opening (P<.001) and anteroposterior movement (P=.01). Also, after treatment, the maximum opening (P<.001) and closing (P=.04) velocities during mastication increased, and improvements in sleep scores for the Pittsburgh Sleep Quality Index (P<.001) and Epworth Sleepiness Scale (P=.04) were found. CONCLUSION: Myofascial pain impairs jaw motion and quality of sleep; the reduction of pain after the use of a stabilization device improves the range of motion and sleep parameters.