Effects of removable dental prostheses on masticatory performance of subjects with shortened dental arches: A systematic review

Comparison of perceived masticatory ability in completely edentulous patients treated with thermoplastic complete denture versus single implant-retained mandibular overdenture: a single-center prospective observational study

Background

This study aimed to compare the perceived masticatory ability (PrMA) in completely edentulous patients (EDPs) with thermoplastic conventional complete dentures (CDs) versus single implant-retained mandibular overdentures.

Methods

The current study was conducted in the outpatient Prosthodontic Clinic, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt. PrMA was evaluated in 45 completely edentulous patients (46% males, mean age 50.4 ± 4.7 years). Each patient received a thermoplastic PMMA complete denture (Polyan IC TM Bredent GmbH & Co.KG, Germany). The PrMA was evaluated at one-month and six-month intervals of denture use. An immediate loading single implant was placed into the mid-symphyseal for each patient, and the denture was adjusted. Subsequently, the PrMA was reevaluated after one month and six months. The data were collected and statistically analyzed using the SPSS@V25 to assess the changes in PrMA.

Results

The PrMA demonstrated improvement after six months of thermoplastic conventional denture use. However, this improvement was not statistically significant (p = 0.405). In addition, the PrMA showed a substantial increase following a single implant placement at one and six months (p < 0.001) of the overdenture use compared to the conventional denture. The PrMA insignificantly improved (p = 0.397) after six months of the single implant retained overdenture use.

Discussion

The study's findings indicate that using immediate loading single implant-retained mandibular overdentures significantly improved PrMA in completely edentulous patients.

The association between objective and subjective oral health conditions and the presence of anorexia of aging among Japanese older Adults1

Anorexia of aging is a risk factor for malnutrition among older adults. This study aimed to evaluate the association between objective and subjective oral health and anorexia among independent older adults. This cross-sectional study targeted independent older adults aged ≥65 years who participated in the Japan Gerontological Evaluation Study conducted in 2022. The outcome variable was the presence of anorexia, as assessed by the Simplified Nutritional Appetite Questionnaire. Exposure variables were dental status (≥20 teeth, 10-19 teeth with/without dentures, and 0-9 teeth with/without dentures) as objective oral health and oral health-related quality of life measured by five items of the short version of the Oral Impacts on Daily Performances (OIDP) (eating, speaking, smiling, emotional stability, and enjoying with others) as subjective oral health. We fitted the Poisson regression model, including possible confounders, and estimated prevalence ratios (PRs) and 95% confidence intervals. Among 19,787 participants (mean age: 74.6 years [1SD = 6.2], male: 48.5%), 9.0% were classified as having anorexia. After adjusting possible confounders, those with ≤19 teeth had a higher proportion of experiencing anorexia compared to those with ≥20 teeth; however, the association was less pronounced among those with dentures (0-9 teeth with dentures: PR = 1.48 [1.31-1.68], and 0-9 teeth without dentures: PR = 2.08 [1.65-2.63]). Even after adjusting for dental status, each item of OIDP was significantly associated with the presence of anorexia (all p < 0.05). The results showed that both objective and subjective poor oral health were significantly associated with a higher probability of developing anorexia of aging. Therefore, improving both objective and subjective oral health through appropriate dental care could contribute to maintaining appetite in later life.

Dental prosthesis use is associated with higher protein intake among older adults with tooth loss

BACKGROUND

Tooth loss is associated with reduced protein intake, which leads to sarcopenia and frailty in older adults.

OBJECTIVE

To evaluate the protective effect of dental prostheses on decreased protein intake in older adults with tooth loss.

METHODS

This cross-sectional study was based on a self-reported questionnaire targeting older adults. Data were obtained from the Iwanuma Survey of the Japan Gerontological Evaluation Study. We used % energy intake (%E) of total protein as the outcome and the use of dental prostheses and number of remaining teeth as explanatory variables. We estimated the controlled direct effects of tooth loss by fixing the use/non-use of dental prostheses based on a causal mediation analysis, including possible confounders.

RESULTS

Among 2095 participants, the mean age was 81.1 years (1SD = 5.1), and 43.9% were men. The average protein intake was 17.4%E (1SD = 3.4) of the total energy intake. Among participants with ≥20, 10-19 and 0-9 remaining teeth, the average protein intake was 17.7%E, 17.2%E/17.4%E and 17.0%E/15.4%E (with/without a dental prosthesis), respectively. Compared to participants with ≥20 remaining teeth, those with 10-19 remaining teeth without a dental prosthesis did not have a significantly different total protein intake (p > .05). Among those with 0-9 remaining teeth without a dental prosthesis, total protein intake was significantly low (-2.31%, p < .001); however, the use of dental prostheses mitigated the association by 79.4% (p < .001).

CONCLUSION

Our results suggest that prosthodontic treatment could contribute to maintaining protein intake in older adults with severe tooth loss.

Tooth loss, denture use, and all-cause and cause-specific mortality in older adults: a community cohort study

Objectives

The available evidence on the connections between tooth loss, denture use, and mortality from all causes or specific causes among older adults is inconclusive. Therefore, we aimed to investigate the association between tooth loss, denture use, and all-cause and cause-specific mortality in older adults.

Methods

A cohort of 5,403 participants aged 65 and older were recruited in the 2014 Chinese Longitudinal Healthy Longevity Survey wave and followed up in the 2018 wave. Cox proportional hazard models were used to examine the association between the number of natural teeth, denture use, and all-cause and cause-specific mortality.

Results

During a mean (SD) follow-up of 3.1  years (1.3), 2,126 deaths (39.3%) occurred. Individuals with 0 and 1-9 teeth had higher mortality due to all-cause, cardiovascular disease (CVD), cancer, and other causes (all p-trend <0.05) than those with 20+ teeth. At the same time, no association was found with respiratory disease mortality. Participants who used dentures had lower mortality due to all causes [hazard ratios (HR) 0.79, 95% confidence intervals (CI) 0.71-0.88], CVD (HR 0.80, 95% CI 0.64-1.00), respiratory disease (HR 0.66, 95% CI 0.48-0.92), and other causes (HR 0.77, 95% CI 0.68-0.88) than those without dentures. Joint analysis revealed that older adults with fewer natural teeth and no dentures had higher mortality. Additionally, interaction analyses showed that the effects of the number of natural teeth on all-cause mortality were more pronounced in older adults aged <80  years (p-value for interaction = 0.03).

Conclusion

Having fewer natural teeth, particularly less than 10 teeth, is linked to an increased risk of mortality from all causes, including CVD, cancer, and other causes, but not respiratory disease. The use of dentures would mitigate the adverse impact of tooth loss on all-cause and some cause-specific mortality.

Impact of unilateral removable partial dentures versus removable partial dentures with major connector on oral health-related quality of life of elder patients: a clinical study

OBJECTIVE

This study aimed to establish the survival rate of unilateral removable partial dentures (u-RPD) comparative with bilateral RPD (bi-RPD) with major connector in elder patients, as well as to determine both their treatment satisfaction and oral health.

METHODS

The study sample included 17 patients treated with u-RPD and 17 patients treated with bi-RPD with a major connector. The patients were followed over five years with recalls every 6 months. A 5- points Likert scale was used to determine the satisfaction of the patients. The Oral Health Impact Profile-14 (OHIP-14) questionnaire was used to evaluate their oral health after each type of administrated treatment. The local oral examined aspects included the maintenance of the abutment teeth periodontal health, the fractures of the removable dentures, the fractures of the connectors, the chipping of the aesthetic material. Kaplan-Meier survival analysis was conducted to evaluate the performance of the two treatments.

RESULTS

The mean survival time in years was 4.882 ± 0.114, 95% CI (4.659; 5.106) and 4.882 ± 0.078, 95% CI (4.729; 5.036), for the u-RPD and the bi-RPD, respectively. The five-year survival rates for the two dentures were 94.1% for u-RPD vs. 88.2% for bi-RPD with a major connector, without a statistically significant difference between them (Log-rank test χ2(1) = 0.301, p = 0.584). The patients receiving u-RPD presented significantly higher satisfaction scores compared to the patients receiving bi-RPD, 4.88 ± 0.48 vs. 4.41 ± 0.62, Mann-Whitney U test, p = 0.026.

CONCLUSION

Patients receiving u-RPD presented higher levels of treatment satisfaction and better oral health than patients receiving bi-RPD. The survival rates of the treatments u-RPD and bi-RPD were similar.

Oral status and incident functional disability: a 9-year prospective cohort study from the JAGES

INTRODUCTION

The population-attributable risk of oral status for incident functional disability remains unknown. We investigated the impact of a range of oral statuses (number of remaining teeth, chewing difficulty, dry mouth, and choking) on incident functional disability.

METHODS

Participants (n = 44,083) aged ≥ 65 years from the Japan Gerontological Evaluation Study were evaluated. The outcome variable was incident functional disability, and the explanatory variables were four select oral statuses. The possible confounders were included as covariates. Using the Cox proportional hazards model, we calculated hazard ratios (HRs), 95% confidence intervals (CIs), and their population-attributable fractions (PAFs).

RESULTS

The mean age of the participants was 73.7 (standard deviation=6.0) years at baseline, and 53.2% were women. A total of 8,091 participants (18.4%) developed functional disabilities during the follow-up period. Among the four oral statuses, the incidence rate of functional disability was the highest in those with chewing difficulty (3.27/100 person-years), followed by those with dry mouth (3.20/100 person-years), choking (3.10/100 person-years), and ≤19 remaining teeth (2.89/100 person-years). After adjusting for all covariates, chewing difficulty showed the highest risk of functional disability (HR=1.22, 95%CI=1.16-1.28), followed by ≤19 remaining teeth (HR=1.18, 95%CI=1.12-1.25), dry mouth (HR=1.18, 95%CI=1.12-1.24), and choking (HR=1.10, 95%CI=1.04-1.17). Regarding PAF, ≤19 remaining teeth (12.0%) were the largest, followed by chewing difficulty (7.2%), dry mouth (4.6%), and choking (1.9%).

CONCLUSIONS

Maintaining a good oral status may reduce the risk of functional disability later in life. Given its population contribution, tooth loss had the largest impact among the four oral conditions.

'Thermo-mechanical behavior of alternative material combinations for full-arch implant-supported hybrid prostheses with short cantilevers'

OBJECTIVES

To compare the fracture resistance (FR) of three combinations of materials for full-arch maxillary implant-supported hybrid prostheses (HPs) with short cantilevers (≤ 10 mm).

METHODS

Maxillary HPs were fabricated and classified as follows (n = 5 each): Group-1 (CC-A, control): acrylic-resin-veneered Co-Cr frameworks; Group-2 (CF-A): acrylic-resin-veneered carbon-fiber mesostructures; and Group-3 (CF-R): composite-resin-veneered carbon-fiber frames. Specimens were thermal-cycled (5,000 cycles; 5 °C-55 °C; dwell time: 30 s). Vertical loads were applied until failure, first at the 10-mm-long cantilever (LC), and, afterwards, at the anterior region (AR), using a universal testing machine (crosshead speed: 0.05 mm/s). The fracture pattern was assessed by stereomicroscope and SEM. The one-way ANOVA, the Bonferroni, and the independent samples t tests, were run (α= 0.05).

RESULTS

At LC, CF-A, and CC-A samples exhibited the highest FR values (p< 0.001), showing no differences to each other. At AR, CC-A specimens recorded the highest FR, followed by CF-A samples (p< 0.001). CF-R HPs displayed the lowest FR at both locations (p< 0.001). The only group with differences between the tested sites was the CC-A, the AR being more resistant (p< 0.001). Most CC-A and CF-A HPs failed cohesively. CF-R prostheses mainly failed adhesively.

CONCLUSIONS

Maxillary HPs with short cantilevers (≤ 10 mm) made of Co-Cr or carbon-fiber veneered with acrylic resin demonstrated an adequate mechanical resistance (> 900 N).

CLINICAL SIGNIFICANCE

For maxillary HPs with cantilevers up to 10 mm, acrylic-veneered carbon- fiber mesostructures may be recommended, whereas coating carbon-fiber frames with composite resin seems not suitable.

Association between masticatory performance and oral conditions in adults: A systematic review and meta-analysis

OBJECTIVES

To give an overview of the evidence on the associations between oral condition factors and masticatory performance of adults, and to evaluate the direction and level of the associations.

DATA/SOURCES

Medline (PubMed), Embase (Ovid) and CINAHL Plus (EBSCOhost) were searched up to May 2022 for cross-sectional studies on oral conditions and masticatory performance in adults. Methodological quality of the included studies was independently evaluated based on the Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between oral condition factors and masticatory performance were extracted. Meta-analysis was conducted on correlation coefficients.

STUDY SELECTION

Of the 8,035 records identified, 97 articles (88 studies) were included in the qualitative synthesis, and 18 studies were included in the meta-analyses. Among the oral condition factors that had associations with masticatory performance, the number of natural/remaining teeth or functional tooth pairs was reported by the largest number of studies, followed by perioral muscle status, dental prosthetic status, oral moisture status and periodontal status. Results of the meta-analyses showed that the positive association with the number of natural/remaining teeth was the strongest (pooled correlation coefficient: 0.51, 95%CI: 0.48 to 0.54), followed by the number of functional tooth pairs, maximum tongue force/pressure, while the association with the oral moisture status was the weakest.

CONCLUSIONS

Number of natural/remaining teeth and functional tooth pairs, perioral muscle status, oral moisture status, dental prosthetic status and periodontal status are the main oral condition factors influencing masticatory performance. Based on the limited evidence available, among these factors, the number of natural/remaining teeth has the strongest positive association, with a very low quality of evidence.

CLINICAL SIGNIFICANCE

This study provides valuable information on the oral condition factors associated with masticatory performance, which would be important for policymakers and clinical practitioners when deciding on the strategies for improving the masticatory performance of adults. This review highlights the need for standardization of measures and classifications of masticatory performance and oral conditions.

REGISTRATION

PROSPERO (registration number: CRD42021256824).

Long-term masticatory performance and ability following closed treatment for unilateral mandibular condylar neck or base fractures: a cross-sectional study

PURPOSE

The aim of this study was to find explanatory variables for objective and patient-reported long-term masticatory functioning in patients treated with maxillomandibular fixation for unilateral condylar neck or base fractures. These outcomes were compared to healthy control subjects.

METHODS

Patients treated between 1996 and 2013 were enrolled in the study. Objective measurements included the mixing ability test (MAT) for masticatory performance, and range of motion of the mandible. Patient-reported measurements included the mandibular function impairment questionnaire (MFIQ) for masticatory ability, and the visual analogue scale for pain. Healthy subjects were recruited between October 2018 and January 2019, and performed the MAT and MFIQ.

RESULTS

Twenty-one patients and 30 healthy subjects were included. The average follow-up period was 11.67 years. In adjusted regression analysis, the amount of occlusal units (OU) was associated with the MAT (P = 0.020; R² = 0.253) and MFIQ (P = 0.001, R² = 0.454). The MAT outcome was similar in both groups when correcting for OU (P = 0.001; R² = 0.201). The MFIQ was inferior in the patient group (P = 0.001).

CONCLUSION

Long-term masticatory performance was similar in patients with a history of condylar neck or base fracture and healthy subjects; however, masticatory ability was inferior in patients compared to healthy subjects.

Associations of general health conditions with masticatory performance and maximum bite force in older adults: A systematic review of cross-sectional studies

OBJECTIVES

To give an overview of the current evidence on the associations of general health conditions with masticatory performance and maximum bite force in older adults.

DATA/SOURCES

Three electronic databases (Medline via PubMed, Embase via Ovid and CINAHL Plus via EBSCOhost) were searched up to September 2021 for cross-sectional studies on general health conditions and masticatory performance or maximum bite force in older adults. Methodological quality of the included studies was independently evaluated based on Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between general health conditions and masticatory performance or maximum bite force were extracted.

STUDY SELECTION

Of the 5133 records identified, 39 studies (43 articles) were included in this review. Significant negative associations were found between masticatory performance and stroke, sarcopenia, amyotrophic lateral sclerosis, chronic obstructive pulmonary disease, dyspepsia, dysphagia, anorexia, and carotid atherosclerosis. Significant negative association was found between maximum bite force and sarcopenia. There were equivocal results on the association between masticatory performance and diabetes mellitus, and between maximum bite force and stroke, and amyotrophic lateral sclerosis. There was no significant association between masticatory performance and metabolic syndrome, and between maximum bite force and progress of Parkinson's disease. Most studies revealed positive associations of physical function with masticatory performance and maximum bite force.

CONCLUSIONS

Negative associations between masticatory function of older adults and presence of several systemic diseases have been reported in a number of studies while there are positive associations between masticatory function and some physical function indicators.

CLINICAL SIGNIFICANCE

This study provides valuable information on the association of masticatory function with general health, which draws clinicians' attention to the masticatory function of older adults who suffer from certain systemic diseases or physical dysfunction, and to the need to improve their masticatory ability to achieve healthy aging.

Dental prosthetic treatment reduced the risk of weight loss among older adults with tooth loss

OBJECTIVES

Weight loss is a critical health issue in older adults. Oral function is essential for nutrient intake and can be restored using dental prosthetic treatments in patients with tooth loss. This study aimed to investigate the relationship between tooth loss and weight loss among the older adults and to evaluate the magnitude of its risk reduction by dental prosthetic treatment.

DESIGN

Three-year follow-up longitudinal study based on a self-reported questionnaire.

SETTING

Community-dwelling older adults in Japan.

PARTICIPANTS

Adults aged 65 and older (n = 53,690).

MEASUREMENTS

We used >10% weight loss during follow-up, the number of remaining teeth, and the use of dental prostheses as the outcome variable, exposure variable, and mediator, respectively. We fitted the logistic regression model including possible confounders and calculated the odds ratios (ORs) and 95% confidence intervals (95% CIs) of the controlled direct effect (CDE) at the level of use or nonuse of the dental prosthesis based on a causal mediation analysis framework. Additionally, we calculated the proportion eliminated by the dental prosthesis.

RESULTS

The mean age of participants was 72.6 years (1 SD = 5.5), and 47.4% were males. About 5.8% (n = 3132) of them experienced >10% weight loss during the follow-up. Weight loss was observed in 6.8% of the participants with 0-19 remaining teeth and in 4.3% of them with ≥20 remaining teeth. The CDE of 0-19 remaining teeth was greater when no one used dental prosthesis (OR = 1.41; 95% CI = 1.26-1.59) compared with that when all participants used dental prosthesis (OR = 1.26; 95% CI = 1.08-1.46). This indicated that dental prosthesis decreased the risk of weight loss by 37.3%.

CONCLUSION

Our study revealed that tooth loss increased the risk of clinically critical levels of weight loss among community-dwelling older adults. However, this risk was reduced by dental prosthetic treatment.

A Prospective Comparative Study of Mastication Predominance and Masticatory Performance in Kennedy Class I Patients

Mastication predominance in Kennedy class I (KC I) patients has not been well defined. This study aimed to investigate mastication predominance and masticatory performance in KC I patients, including the significance of remaining posterior teeth and removable partial-denture (RPD) treatment. KC I patients who had differences in the number of posterior teeth between left and right sides (D+) and KC I patients who had no differences (D−) were enrolled. Healthy dentate (HD) subjects were also registered as a positive control. Mastication predominance, defined by mastication predominance index (MPI; range 0–100%) calculated from electromyogram activities during voluntary chewing, and masticatory performance were evaluated at pre- and post-RPD treatment. Pre-MPI in KC I D+ was significantly higher than in HD. RPD treatment could significantly improve MPI and masticatory performance in both KC I groups. However, there were significant differences in masticatory performance between each KC I group and HD, regardless of RPD treatment. It was considered that the mastication predominance in KC I patients was affected by the difference in the number of remaining posterior teeth. RPD treatment could improve mastication predominance and masticatory performance in KC I patients, although the latter was not similar to HD group.

The deterioration of oral function and orofacial appearance mediated the relationship between tooth loss and depression among community-dwelling older adults: A JAGES cohort study using causal mediation analysis

BACKGROUND

Depression is a major health problem among older adults, for which previous studies have suggested tooth loss as a risk factor. This study examined the mediating effect of oral function and orofacial appearance in the relationship between tooth loss and depression.

METHODS

This three-year follow-up longitudinal study was based on a self-reported questionnaire targeting community-dwelling older adults aged ≥65 years. We used the incidence of depressive symptoms during follow-up as the outcome, the number of remaining teeth (≥20/≤19) as the exposure, and the deterioration of oral function and orofacial appearance (speaking, smiling, and eating) as mediators. We fitted the logistic regression model including confounders and calculated the natural indirect effect (NIE), natural direct effect, and the proportion mediated (PM) by the deterioration of oral functions by applying the causal mediation analysis framework.

RESULTS

The mean age of the 8,875 participants was 72.7 years (1SD=5.5) and 48.0% were male. Depressive symptoms developed during follow-up in 11.5% of the participants (n=1,024). The incidence for those with ≤19 and ≥20 remaining teeth was 13.1% and 9.2%, respectively. Total effect of fewer remaining teeth (≤19) on depressive symptoms was OR=1.30 (95%CI=1.12-1.51). Difficulty in speaking (NIE OR=1.03, 95%CI=1.00-1.06, PM=12.4%), problems in smiling (NIE OR=1.04, 95%CI=1.01-1.07, PM=16.9%), and difficulty in chewing (NIE OR=1.05, 95%CI=1.02-1.09, PM=21.9%) significantly mediated the relationship.

LIMITATION

Selection bias due to dropout.

CONCLUSION

Deterioration of oral function and orofacial appearance were mediating factors of the mechanism for the relationship between tooth loss and the incidence of depressive symptoms.

What variables are associated with use of and need for dental prosthesis? A cross-sectional study

BACKGROUND

Population-based studies assessing the factors associated with use of and need for dental prosthesis among older adults are scarce.

OBJECTIVE

To evaluate the use of and need for dental prosthesis and associated factors in the older adult population of a southern city of Brazil.

MATERIAL AND METHODS

A cross-sectional study, involving community-dwelling older adults (≥60 years), was performed. A probabilistic per cluster sampling was used, and 282 participants from Veranópolis, Brazil, were included. A clinical oral health examination was performed, and a structured questionnaire was applied. Bivariate and multivariate analyses were performed to verify associations using Poisson regression with robust variance.

RESULTS

The prevalence of use of dental prosthesis was 87.2% (n = 246), while the prevalence of need for dental prosthesis was 27% (n = 76). Older adults with medium/high levels of education had 17.8% (P = .019) lower prevalence ratio (PR) for use of dental prosthesis. Unmarried and retired older adults had, respectively, 11.1% (PR:1.111; 95%CI:1.022-1.207) and 19.5% (PR:1.195; 95%CI:1.009-1.415) higher PR for use of prosthesis. Those without access to dental care had 11.8% (P = .012) higher PR for use of dental prosthesis. Older adults living in rural areas had 64.7% (PR:1.647; 95%CI:1.079-2.514) higher PR of need for dental prosthesis.

CONCLUSION

High and low prevalence of use of and need for dental prosthesis, respectively, were detected in this sample. Level of education, marital status, retirement status and access to dental care were associated with the use of dental prostheses. However, only residence area was associated with the need for oral rehabilitation.

Considerations for the Prosthetic Dental Treatment of Geriatric Patients in Germany

Demographic changes in the industrialized countries require that dentists adapt to the growing and heterogeneous group of elderly patients and develop concepts for the dental care of fit, frail, and dependent old and very old people. In general, dental care for old and very old people should be based on their individual everyday life. As a result of demographic changes, improved oral hygiene at home, and the establishment of professional teeth and denture cleaning, tooth loss occurs increasingly in higher ages, which implies that first extensive prosthetic rehabilitation with fixed or/and removable dental prostheses is shifting to a higher average age than ever before. This phenomenon requires that the individual diseases, potential multimorbidity and polypharmacy, and associated limitations are taken into consideration. Against this background, the current survey aims to summarize epidemiological trends associated with tooth loss, using Germany as a highly representative country for demographic changes as an example. Furthermore, the current narrative summary outlines general principles that should be followed in dental care, treatment of geriatric patients, and outlines current therapeutic options in prosthetic dentistry.

Breaking the vicious circle of diet, malnutrition and oral health for the independent elderly

Aging impairs senses, mastication, oral status and function, causing nutritional needs and diet insufficiencies. The present needs of independent older adults suggest that health research and oral health care should shift from reductionist disease management to integral and personal treatment plans, including lifestyle, psychological, nutritional and oral health coaching approaches. Dentists and other medical professionals that work in the field of gerodontology should be educated on the macro and micronutrient needs of the elderly and incorporate certain nutritional plans early in the life of their patients with their approval and cooperation, in order to postpone tooth loss and masticatory impairment. Old recipes such as the Mediterranean diet should be kept as a base for all the elderly and be enriched in a customized interpersonal way from the dentist as well as the medical professional according to the specific needs of one's oral and general health status. In this nonsystematic review paper, the basic aspects of the vicious cycle of nutrition and oral health status are discussed and suggestions of major nutrients' influence and needs for independent elders are reported. Based on the scientific data collected, suggestions are made for the food industry for better quality and dosage of foods for this category of individuals. Such strategies can be a whole new area of interest for the food industry in order to obtain better quality of food packaging for the independent OA with accepted texture, odor, colors, macronutrients and micronutrients' consistency and in specific portions.

Masticatory Adaptation to Occlusal Changes

This review deals with the frequent wide variability of masticatory capacity/incapacity. Neither researchers nor clinicians have taken sufficient account of this variability despite its implications for nutrition. Mastication in normal healthy oral conditions is first described, followed by a short presentation of the mechanisms of masticatory adaptation in the nervous system. Capacity, incapacity, and successful compensatory adaptation of mastication are then defined, along with the different methods used for their evaluation. Examples of adaptation needs are given, such as those concomitant with dental wear or occlusal changes. Finally, given its vital importance for deeply impaired mastication/deglutition function, the impact of masticatory adaptation processes on nutrition is examined.

Differences in comminution progress during mastication in healthy dentate and denture-wearing elderly people

PURPOSE

This study aimed to investigate the effect of removable denture prostheses on the comminution progress in elderly people.

METHODS

Twenty-two denture wearers of Eichner's classification B and C (75.1±5.3 years old) and 20 young fully dentate subjects (27.6±1.9 years old) participated in the masticatory examination, which used a combined test food from 5 daily food materials. Full masticatory cycles lasting until subjects needed to swallow and the half number of the cycles were adopted as masticatory conditions. Digital images of food particles under wet conditions were obtained for each bolus, and particles were analyzed by calculating the homogeneity and particle size indices.

RESULTS

The characteristic properties of the food particles were observed using a homogeneity index in the elderly denture group for half masticatory strokes. Their homogeneity index was significantly higher than that of the young dentate group. By contrast, no significant difference was observed in the indices for particles immediately before swallowing between two groups.

CONCLUSIONS

The comminuted particle size before swallowing in healthy denture wearers was not significantly different from that in the natural dentate group. The comminution of the first-half process in denture wearers was typical and could be one possible focus for meal property specifications in future studies.

Reciprocal cortical activation patterns during incisal and molar biting correlated with bite force levels: an fMRI study

In humans, the incisors and molars have distinct functions during mastication, analogous to the two main types of handgrip, the precision and power grips. In the present study, we investigated cortical activation and masticatory muscle activity during incisal and molar biting via simultaneous functional magnetic resonance imaging and electromyogram (EMG) recordings. We conducted recordings in 15 healthy adult participants while they performed incisal and molar biting tasks at three step-wise force levels using two custom-made splints. Regarding the results of the ROI analysis, we found a significantly stronger positive linear correlation between the blood oxygenation level dependent signal and EMG activity during molar biting than incisal biting, which was particularly prominent in the primary sensorimotor cortex and the cerebellum. We also found a significantly stronger negative linear correlation during incisal biting than molar biting, which was particularly prominent in the rostral cingulate motor area, superior frontal gyrus, and caudate nucleus. These findings indicate that molar biting enables powerful chewing: brain activity in several brain areas related to motor function was increased with increasing bite force levels, while incisal biting enables fine motor control: brain activity in several brain areas related to motor control was increased with reduced bite force levels.

The influence of habitual consumption of chewing gums in the outcome of masticatory performance tests using two-coloured chewing gums

The aim of this study is to assess the influence of regular consumption of chewing-gums on the Masticatory Performance (MP); and to determine if increasing the consumption improves the MP of non-regular consumers. We recorded the chewing-gums consumption rate (CGC) and measured the MP of 265 participants (µ = 47.09, σ = 22.49 years) using the Variance of the Histogram of the Hue (VhH) image processing method. Then, participants were instructed to increase the consumption, and the MP was measured again (SESSION) two and four days after. Normality of MP was verified with Kolmogorov-Smirnov and Shapiro-Wilk tests. The association between the age and the consumption rate was measured with GEE and the eta-squared statistic. Finally, a 3 × 3 mixed ANOVA with SESSION as the within-subject factor and CGC as the between-subjects factor was run. Session-wise and group-wise comparison were performed with post hoc Bonferroni. No systematic error was detected for VhH (p = 1.00). Kolmogorov-Smirnov and Shapiro-Wilk tests confirmed the normality of the distribution of MP (p > 0.05). There was a significant effect of SESSION on MP, F(1.746, 457.328) = 59.075, p < 0.001; furthermore, there were significant differences in MP between SESSIONs. Additionally, there was a significant effect of CGC on MP, with F (2, 356.53) = 564.73, p < 0.001. In conclusion, the chewing-gum consumption habits influence the two-coloured chewing gum mixing test. The apparent MP of non-regular consumers can be improved by prescribing a controlled increase in the consumption of chewing-gums for a few days.

The Association of Poor Oral Health Parameters with Malnutrition in Older Adults: A Review Considering the Potential Implications for Cognitive Impairment

Poor dental status and chewing deficiencies have been associated with cognitive decline. Altered dietary habits and malnutrition have been suggested as linking mechanisms. The aim of the present review was thus to investigate if poor oral health, and in particular tooth loss and impaired masticatory function, may affect dietary selection and nutritional intake in older adults, and moreover, to assess if prosthodontic dental care may improve nutritional status. Extensive tooth loss may impair masticatory function. Several studies in older populations have shown that severe tooth loss and masticatory impairment are associated with limited consumption of various food types (especially fruits and vegetables), increased consumption of sugary and easy-to-chew foods, and lower dietary intake of fibre and vitamins. However, these findings are not consistently reported, due to methodological variation among studies, potential adverse causalities, and the multifactorial nature of food choices. On the other hand, a few interventional studies revealed that prosthetic rehabilitation of missing teeth, when accompanied by dietary counselling, may improve dietary habits and nutritional intake. Further research is required to improve current knowledge of these associations. Under the limitations of the current study, a functional dental arch of natural or artificial teeth is important for maintaining adequate chewing efficiency and ability, but this only partly contributes to food choices and nutritional status. The multifactorial nature of food choices necessitates the interprofessional collaboration of dental professionals, dietetics practitioners, and primary care providers to improve dietary habits and nutritional intake.

Masticatory efficiency in patients with partially dentate dentitions

OBJECTIVES

To assess associations amongst masticatory performance, dental functional status, and perceived chewing problems with common soft and hard foods.

MATERIALS AND METHODS

387 adult participants with reduced natural dentitions were included and underwent an oral examination, completed a written structured questionnaire and performed a two-color chewing gum test for masticatory efficiency. A multivariate regression model was used to analyze associations between masticatory efficiency and a number of dental conditions, with age, gender and perceived chewing difficulties as background variables. Likelihood ratios were calculated to analyze the relationship between masticatory efficiency and dental conditions within a validated hierarchical dental functional classification system expressed by (1) number of teeth in upper and lower jaw, (2) completeness of anterior regions, (3) number of premolar occluding pairs, and (4) number of molar occluding pairs.

RESULTS

The regression model showed a significant positive association between unmixed ratio and self-reported problems with chewing (p = .004), and age (p < 0.001), and negative associations with having a sufficient premolar region (p < 0.001). In the hierarchical dental functional classification system, the likelihoods of having a high unmixed ratio and chewing problems with hard foods were highest for the predictor 'less than 10 teeth in each jaw' (LRs 4.01, respectively 13.06).

CONCLUSIONS

In partially dentates people, perceived chewing difficulties were associated with lower objective masticatory efficiency. Having fewer than 10 teeth in each jaw and having an impaired premolar region were best predictors for low masticatory efficiency.

CLINICAL SIGNIFICANCE

This study shows that having fewer than 10 teeth in each jaw and having an impaired premolar region are associated with low masticatory efficiency and chewing problems. Preservation of at least 10 teeth in each jaw and 3 to 4 premolars is important for preventing chewing difficulties.

The relationship between masticatory ability, age, and dental and prosthodontic status in an institutionalized elderly dentate population in Qingdao, China

Objectives

To identify relationships between masticatory ability and age, and dental and prosthodontic status amongst an institutionalized elderly dentate population in China.

Materials and methods

A sample of 512 elders living in eight nursing homes in Qingdao was categorized based on a hierarchical dental functional classification system with and without tooth replacements. Masticatory disability scores (MDSs) were analyzed using multiple regression models with only age, and age and dentition variables for participants having ≥ 10 natural and those having < 10 natural teeth in each jaw.

Results

Overall, associations between MDS and age, number of teeth, and number of teeth replaced by dental prostheses were identified. For participants having ≥ 10 natural teeth in each jaw, no significant associations between MDS and age and dental and prosthodontic status were found. Participants having < 10 natural teeth in each jaw had higher MDS (increasing chewing difficulties) at higher ages. However, when “premolar region sufficient” and “molar region sufficient” were included, MDS was not associated with age, but with these dentition variables. For participants having ≥ 10 teeth including prosthodontically replaced teeth in each jaw, age was the only variable associated with MDS. For participants having < 10 teeth including teeth replaced in each jaw, the significant factor was “premolar region sufficient.” Overall, lower MDS was associated with increasing number of teeth, as well as with increasing number of teeth replaced by dental prostheses.

Conclusions

In this population of institutionalized dentate elderly, masticatory ability was significantly associated with dental and prosthodontic status.

Clinical relevance

For institutionalized elderly, having less than ten natural teeth in each jaw is associated with chewing problems. Most important dentition factor is the presence of three to four premolar pairs. Teeth added by partial removable dental prostheses compensate impaired masticatory ability due to tooth loss for 50% compared to natural teeth.

Surveillance and monitoring of oral health in elderly people

Continued ageing of the global population is expected to pose significant challenges to maintaining optimum lifelong health in individuals and populations. Oral health is an essential element of general health and quality of life throughout an individual's life course, yet it is often neglected in integrated approaches to general health promotion. Surveillance and monitoring systems are essential for developing oral health policy and strategy at both national and community levels. As major oral diseases, dental caries and periodontal diseases are core indicators for surveillance at every stage of life. In addition, oral mucosal lesions and masticatory function are essential indicators, especially in an ageing population. The assessment of risk factors such as tobacco use, alcohol consumption or dietary habits (e.g., sugar intake) is also important for oral disease prevention. Although surveillance is conducted through clinical examinations (normative assessments), this method is becoming more difficult to use because of high costs and human resource shortages, even in high-income countries. Alternative and less resource-demanding approaches, such as self-reported protocols, are therefore needed at the global level. The World Health Organization's (WHO) oral health surveillance and monitoring activities have evolved into the Oral Health STEPwise approach, which includes questionnaire surveys (Step 1) and clinical examinations (Step 2). Collaboration between international organisations such as the World Dental Federation (FDI), WHO and the International Association for Dental Research (IADR) is now needed to coordinate global oral health surveillance and monitoring systems.

Shortened dental arch as a solution for maxillary sinus proximity in dental implant restoration

This case report demonstrates the benefit of using the shortened dental arch (SDA) design for a comprehensive implant-supported restoration and the avoidance of the complexities of implant placement near the maxillary sinus. The SDA concept as a treatment option is encouraging in terms of function, patient satisfaction, and cost-effectiveness.

Methods for objectively assessing clinical masticatory performance: protocol for a systematic review

BACKGROUND

Chewing and masticatory function constitutes one of the most important oral health factors that affect quality of life, especially in older individuals. Little consensus currently exists regarding ways to objectively assess clinical masticatory performance (in this context, performance refers an individual's objective ability to mix or comminute food bolus). That said, many methods were developed to assess masticatory performance. Consequently, systematic review of the literature would be of great value when it comes to identifying various methods for objectively assessing clinical masticatory performance and for evaluating these methods.

DESIGN

This study protocol describes a systematic review that intends to (i) identify methods to objectively assess clinical masticatory performance and (ii) evaluate psychometric properties (such as validity and reliability) of the identified methods. A systematic literature search is required to do so in these sources: MEDLINE (Ovid), Embase (embase.com), Web of Science Core Collection (Thomson Reuters), Cochrane (Wiley), and Cinahl (Ebsco).

INCLUSION CRITERIA

studies in scientific, full-text articles; development articles; validation articles; studies of the general adult population, ages ≥18.

EXCLUSION CRITERIA

topics and article types that cover interview methods and self-reported questionnaires; methods/instruments that measure subjective masticatory performance; qualitative studies and case studies; opinion and editorial pieces; animal studies; studies of humans with severe oral health complications.

DISCUSSION

This systematic review will result in a comprehensive assessment of various methods designed to objectively measure clinical masticatory performance. This systematic review will rate these methods, assess their reliability and validity, and identify one or more methods that can be recommended for use in clinical and scientific environments. From what is currently known, no systematic evaluation of various methods for objectively assessing clinical masticatory performance has been published.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016037700.

Annual review of selected scientific literature: Report of the committee on scientific investigation of the American Academy of Restorative Dentistry

STATEMENT OF PROBLEM

It is clear the contemporary dentist is confronted with a blizzard of information regarding materials and techniques from journal articles, advertisements, newsletters, the internet, and continuing education events. While some of that information is sound and helpful, much of it is misleading at best.

PURPOSE

This review identifies and discusses the most important scientific findings regarding outcomes of dental treatment to assist the practitioner in making evidence-based choices. This review was conducted to assist the busy dentist in keeping abreast of the latest scientific information regarding the clinical practice of dentistry.

MATERIAL AND METHODS

Each of the authors, who are considered experts in their disciplines, was asked to peruse the scientific literature published in 2015 in their discipline and review the articles for important information that may have an impact on treatment decisions. Comments on experimental methodology, statistical evaluation, and overall validity of the conclusions are included in many of the reviews.

RESULTS

The reviews are not meant to stand alone but are intended to inform the interested reader about what has been discovered in the past year. The readers are then invited to go to the source if they wish more detail.

CONCLUSIONS

Analysis of the scientific literature published in 2015 is divided into 7 sections, dental materials, periodontics, prosthodontics, occlusion and temporomandibular disorders, sleep-disordered breathing, cariology, and implant dentistry.