Digital oral health biomarkers for early detection of cognitive decline.

BACKGROUND: Oral health could influence cognitive function by stimulating brain activity and blood flow. The quantified oral status from oral inflammation, frailty and masticatory performance were rarely applied to the cognitive function screening. We aimed to adopt non-invasive digital biomarkers to quantify oral health and employ machine learning algorithms to detect cognitive decline in the community. METHODS: We conducted a prospective case-control study to recruit 196 participants between 50 and 80 years old from Puzi Hospital (Chiayi County, Taiwan) between December 01, 2021, and December 31, 2022, including 163 with normal cognitive function and 33 with cognitive decline. Demographics, daily interactions, electronically stored medical records, masticatory ability, plaque index, oral diadochokinesis (ODK), periodontal status, and digital oral health indicators were collected. Cognitive function was classified, and confirmed mild cognitive impairment diagnoses were used for sensitivity analysis. RESULTS: The cognitive decline group significantly differed in ODK rate (P = 0.003) and acidity from SILL-Ha (P = 0.04). Younger age, increased social interactions, fewer cariogenic bacteria, high leukocytes, and high buffering capacity led to lower risk of cognitive decline. Patients with slow ODK, high plaque index, variance of hue (VOH) from bicolor chewing gum, and acidity had increased risk of cognitive decline. The prediction model area under the curve was 0.86 and was 0.99 for the sensitivity analysis. CONCLUSIONS: A digital oral health biomarker approach is feasible for tracing cognitive function. When maintaining oral hygiene and oral health, cognitive status can be assessed simultaneously and early monitoring of cognitive status can prevent disease burden in the future.

Assessment of subjective and objective masticatory function among elderly individuals with mild cognitive impairment.

BACKGROUND: Masticatory function is known to be related to cognitive ability; therefore, factors for improving masticatory function should be identified. AIMS: This study aimed to identify factors influencing masticatory function associated with mild cognitive impairment (MCI) in elderly individuals. METHODS: A total of 123 elderly participants [mean age: 76.5 ± 6.5 years; 82 females (66.7%), 41 males (33.3%)] were included. Cognitive function was evaluated by the Korean version of the Mini-Mental State Examination (KMMSE). Questionnaires for subjective evaluation were administered, and dynamic objective masticatory function evaluations, including chewing tests and bite force measurements, were performed. Intergroup differences were evaluated by the Wilcoxon rank-sum and chi-square test, and correlations between cognitive ability and masticatory function were evaluated by multilinear logistic regression. RESULTS: The number of teeth, number of posterior teeth, bite force, masticatory ability index (MAI) and posterior support status showed significant differences between the normal (KMMSE > 23) and MCI (KMMSE ≤ 23) groups. However, only the MAI, representing dynamic masticatory performance, was significantly associated with MCI regardless of age, sex and removable prostheses. The number of teeth and posterior teeth, bite force, subjective masticatory ability and posterior occlusal support showed no significant association with MCI. DISCUSSION: These results suggested the importance of chewing function for preventing the progression of cognitive impairment. CONCLUSIONS: Considering that only the MAI was significantly associated with MCI, it is more important to improve chewing efficiency by harmonizing therapeutic prosthetics with the surrounding masticatory system than simply increasing the number of teeth to prevent or delay cognitive impairment in elderly individuals.

Mastication in health-related quality of life in patients treated for oral cancer: A systematic review.

INTRODUCTION: Treatment for oral cancer can impair oral functions such as mastication, which may negatively affect quality of life (QoL). In this review, an overview is provided of masticatory ability in patients treated for oral cancer. METHODS: The PubMed (MEDLINE), Embase and Cochrane databases were systematically searched for scientific literature on masticatory ability in relation to QoL in patients treated for oral cancer. Studies were included when oral cancer treatment was provided, and the University of Washington Quality of Life (UW-QoL) questionnaire was used. Risk of bias (MINORS) was independently assessed by two authors. RESULTS: The PubMed (MEDLINE), Embase and Cochrane search yielded 575 unique records of which 111 were assessed full text, and 27 studies were included. The UW-QoL mastication scores ranged from 31.9 to 97.4. There was a wide variety in methodology, patient groups, tumour site, treatment and assessment moment, to such a degree that outcome scores are difficult to compare. CONCLUSION: The wide variety in studies exploring health-related QoL in relation to mastication in oral cancer patients prevents the identification of possible relations between treatment, masticatory ability and QoL. Our findings underline the limitations in currently available literature and indicate the necessity for more comparable research.

Masticatory ability in older individuals: A qualitative interview study.

AIM: To explore older individuals' experienced masticatory ability and the impact of masticatory ability in daily life. MATERIAL AND METHODS: This study applied an open-ended exploratory approach using inductive reasoning. The design was inspired by the qualitative method grounded theory. The final sample consisted of twelve older participants. Seven were men, and five were women. The interviews were audio-recorded and transcribed verbatim. The interviewer successively read the transcribed data and analysed the material in cooperation with the authors. RESULTS: Three categories developed from the data; Deteriorating oral health and functional loss, Eating habits, Prosthetic rehabilitation and function. A core category named Adaptation emerged. Adaptation describes how individuals successfully could adapt to a decreased function and in spite of this develop a positive view of their masticatory ability. DISCUSSION: The participants described an experience of gradually deteriorating oral function that had affected their masticatory ability. By adapting to this functional degradation, some of the participants overcame the functional deficiencies. Most participants perceived their masticatory ability to be good, even though their ability to process some food types was described as inadequate. CONCLUSION: The participants had experienced deteriorating oral health and function throughout life, and they overcame this through adaptation by adjusting their eating habits. Even though prosthetic treatment might be considered successful by the participant, this does not necessarily improve dietary habits. Future research should therefore focus on how dental treatment can be combined with other interventions, such as dietary counselling and physiotherapy to recover physiological function.

Food avoidance is associated with reduced dentitions and edentulousness.

OBJECTIVES: To investigate associations between food avoidance and dental status, age, gender, and socio-economic status (SES). MATERIALS AND METHODS: The Chinese sample comprised 1463 dentulous (≥ 1 tooth in each jaw) and 124 edentulous (in one or both jaws) participants aged ≥ 40 yrs. The Vietnamese sample comprised 2820 dentulous and 253 edentulous participants aged ≥ 20 yrs. Food avoidance due to chewing difficulties was scored for regionally common 4 soft and 4 hard foods. Dental status was classified according to the multi-level hierarchical dental functional classification system (HDFC) based on the number and location of teeth and posterior occlusal pairs. Associations were analyzed using multivariate logistic regression analyses. RESULTS: For dentulous participants, the chance of avoiding foods was significantly larger with < 10 teeth in each jaw (OR = 2.26 (Chinese sample), respectively 1.74 (Vietnamese sample)), incomplete anterior region (OR = 1.78, respectively 1.84), "impaired" premolar region (OR = 2.22, respectively 1.71), or "impaired" molar region (OR = 2.46, respectively 1.84). Edentulous participants had twice the chance of avoiding foods (OR = 2.01 respectively 2.20). Avoiding foods was significantly associated with higher age. Participants of low SES (Chinese sample, OR = 1.93) and females (Vietnamese sample, OR = 1.27) had a larger chance of avoiding foods. CONCLUSIONS: Avoiding foods was significantly associated with reduced dentitions, edentulousness, and higher age; low SES only in the Chinese and being female only in the Vietnamese sample. CLINICAL RELEVANCE: Incomplete anterior regions, "impaired" premolar or molar regions, and especially edentulousness can be considered significant risk indicators for food avoidance.

Association between mastication-related factors and the prevalence of dementia in Korean elderly women visiting senior centres.

OBJECTIVE: The purpose of this study was to evaluate the mastication ability of elderly women by assessing the number of their remaining teeth, subjective mastication comfort, subjective chewing ability of five food items, relative occlusion balance and mastication performance involving in chewing gum. BACKGROUND: Korea has already entered an aged society, issues related to the elderly are also growing; for example, dementia is emerging as a social problem. In addition, oral health of the elderly is very important because it is directly related to nutrient intake. A total of 101 subjects aged ≥65 who attended senior citizen centres in Daegu city provided consent and were included in this study. MATERIALS AND METHODS: The Korean version of the Mini-Mental State Examination (MMSE-DS) was used to evaluate cognitive function. To assess the degree of objective mastication, we measured colour changes using a chewing gum and posterior occlusion force using a T-scan Ⅲ® system. RESULTS: There was an association between mastication ability and cognitive function, indicated by the colour changes in the chewing gum (P < .05). The participants with greater relative posterior occlusion forces had higher MMSE-DS scores than those with stronger relative anterior occlusion forces. There was a positive correlation between cognitive function and posterior occlusion force. CONCLUSION: The elderly having more occlusion force of posterior teeth rather than anterior teeth were associated with better cognitive ability. Therefore, it may be important for the elderly to restore the masticatory function for the posterior part to prevent against deterioration of cognitive function.

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.

Relationship between tooth loss, low masticatory ability, and nutritional indices in the elderly: a cross-sectional study.

BACKGROUND: Low masticatory ability and the resulting decrease in intake of masticable foods can result in undernutrition. The present study investigated the relationship between tooth loss, low masticatory ability, and nutritional indices in the elderly. METHODS: The data analyzed in this study were retrieved from the baseline data of the 2007 Fujiwara-kyo study, a prospective cohort study of community-dwelling elderly individuals. Subjects included 1591 men and 1543 women, both with a median age of 71 years. The maximum occlusal force was measured as an objective index of masticatory ability. Foods were divided into five groups based on hardness: Group 1 (bananas, etc.), 0.53 kg; Group 2 (boiled rice, etc.), 1.22 kg; Group 3 (raisins, etc.), 2.93 kg; Group 4 (raw carrots, etc.), 4.38 kg; and Group 5 (beef jerky), 6.56 kg. To obtain a subjective index of masticatory ability, a questionnaire-based survey was conducted to determine whether subjects could masticate foods within each group. As nutritional indices, serum albumin levels and body mass index (BMI) data were used. RESULTS: The median number of teeth was 21. The proportion of subjects for whom all five food groups were masticable showed a significant decrease in the number of teeth in both males and females. Logistic regression analysis showed that, after adjustment for confounders, no significant relationships were observed between the number of teeth and the masticatory ability with nutritional indices in males. In females, a maximum occlusal force of 100 to 300 N (OR = 1.65; 95% CI = 1.06-2.55) or less than 100 N (OR = 1.95; 95% CI = 1.15-3.31) showed a significant correlation with serum albumin levels below 4.4 g/dL (reference: 500 N or more). In addition, the masticability of all five food groups showed a significant correlation with BMI < 21.0 kg/m2 (OR = 0.62; 95% CI = 0.46-0.85) in females. CONCLUSIONS: A low number of teeth was associated with low masticatory ability in both males and females. Low masticatory ability was associated with low plasma albumin levels and low BMI in females. Not smoking, maintaining grip strength, preventing cancer, and masticatory ability are important for preventing undernutrition.

Relationship between oral health and Fried's frailty criteria in community-dwelling older persons.

BACKGROUND: Oral health and frailty might be linked through several pathways, but previous studies are scarce. This study examined the association between oral health and components of Fried's frailty phenotype. METHODS: This cross-sectional analysis was based on a sample of 992 community-dwelling persons aged 73 to 77 years observed in the 2011 follow-up of the Lausanne 65+ cohort (Lc65+) study. Data were collected through annual mailed questionnaires, interview and physical examination. Oral health was assessed according to self-reported oral pain and masticatory ability. Frailty was defined as meeting at least one criterion of the Fried's phenotype. RESULTS: Oral pain was reported by 14.8% and chewing problems by 9.7%. Impaired masticatory ability (IMA) was more frequent in subjects with missing teeth or removable dentures (13.5%) than among those with full dentition or fixed dental prostheses (3.2%). In logistic regression analyses adjusting for demographics, alcohol consumption, smoking, comorbidity and financial difficulties, persons with oral pain and those with chewing problems had significantly higher odds of being frail (adjusted ORpain = 1.72; 95% CI 1.17-2.53 and adjORIMA1.70; 1.07-2.72, respectively). Lack of endurance was associated with both oral pain (adjOR = 3.61; 1.92-6.76) and impaired masticatory ability (adjOR = 2.20; 1.03-4.72). The latter was additionally linked to low physical activity (adjOR = 2.35; 1.29-4.28) and low gait speed (adjOR = 3.12; 1.41-6.90), whereas oral pain was associated with weight loss (adjOR = 1.80; 1.09-2.96) and low handgrip strength (adjOR = 1.80; 1.17-2.77). CONCLUSION: Self-reported oral pain and chewing impairment had a significant relation with frailty and its components, not only through a nutritional pathway of involuntary weight loss. Longitudinal analyses are needed to examine whether a poor oral condition might be a risk factor for the onset of frailty.

Association between functional tooth units and chewing ability in older adults: a systematic review.

OBJECTIVES: To systematically review the current evidence on the relationship between dentition status and chewing ability in older adults, as the latter was subjectively perceived by questionnaires. BACKGROUND: Tooth loss is associated with functional impairment regarding chewing ability, depending on the number and the location of the remaining teeth. METHODS: A search of the English literature was undertaken using the appropriate electronic databases and keywords in order to answer the question of this review. Independent extraction of the related articles was carried out by two authors using predefined eligibility criteria. RESULTS: Full-text analysis was performed for 51 articles of possible relevance. Finally, data were extracted from 18 studies, published in 20 articles that met the inclusion criteria. CONCLUSIONS: Although there was a conflict between the studies relevant to the number of functional tooth units needed to maintain adequate oral function, it was revealed that chewing ability was closely related to the number and distribution of teeth remaining. Treatment plan should focus on the preservation of the strategic parts of the dental arch that are critical for adequate oral function. Long-term prospective studies, comprising well-defined criteria, clinical variables, methods and utilising comprehensive questionnaires, should be preferred to obtain a clearer picture on the association between masticatory ability and functional tooth units.

Relationship between masticatory ability and physical performance in community-dwelling edentulous older adults wearing complete dentures.

OBJECTIVE: This study aimed to elucidate the association between masticatory ability and physical performance in community-dwelling edentulous older adults wearing complete dentures. BACKGROUND: Physical performance parameters are significant predictors of decreased activities of daily living. Previous studies have shown the relationships between oral conditions and these parameters. Here, we focused on complete denture wearers. METHODS: Two hundred and ten edentulous adults aged ≥65 years and wearing complete dentures were enrolled. The following oral conditions were examined: masticatory ability measured by colour-changing chewing gum, number of foods considered chewable, pain when using dentures and denture base fit. Handgrip strength (HG) and one-leg standing time with eyes open (OLST) were used to evaluate muscle strength and static balance. Spearman's rank correlation coefficients were calculated to examine the correlations between oral conditions and physical performance. Forward stepwise linear regression models were applied with each physical performance parameters as the dependent variable and oral conditions as the independent variable. RESULTS: The women did not show significant correlations between oral conditions and the physical performance. In men, significant and positive correlations were found between the number of chewable foods and HG, and between the colour scores and OLST. The significant correlation between the colour scores and OLST was still noted in the stepwise liner regression analysis after adjusting for demographic, social and medical conditions, and other oral conditions. CONCLUSION: In Japanese elderly edentulous men wearing complete dentures, masticatory ability evaluated as the mixing ability may be associated with static balance.

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.

Effects of maxillofacial prosthetic treatment on oral health-related quality of life and masticatory ability of patients with head and neck tumors.

PURPOSE: Using multivariate analysis, this study investigated the effectiveness of maxillofacial prosthetic treatment in relation to oral health-related quality of life (OHR-QoL), masticatory ability (food intake status score and gum-jelly test score) and related factors in patients who had undergone surgery for head and neck tumors. METHODS: The study cohort comprised 112 patients who underwent surgical resection and prosthetic treatment among 224 patients with head and neck tumors seen at the Maxillofacial Prosthetics Clinic of Tohoku University Hospital in a 2-year period. Correlations between OHR-QoL, food intake status score, and gum-jelly test score (criterion variables), and age, sex, maxillary defect, tongue/soft tissue defect, reconstructive surgery, and chemoradiotherapy (explanatory variables) were investigated, and the data were examined statistically. RESULTS: Maxillary defect, tongue and soft palate tissue defect, and chemoradiotherapy were identified as factors that hindered the effectiveness of maxillofacial prosthetic treatment for improvement of the OHR-QoL, food intake status score, and gum-jelly test score. On the other hand, reconstructive surgery was a factor that facilitated the improvement of OHR-QoL and masticatory ability with maxillofacial prosthetic treatment. CONCLUSION: The factors identified to be related to the success or failure of maxillofacial prosthetic treatment suggest the importance of combining prosthetic intervention with surgical reconstruction.

Fabrication of a 3D-Printed Interim Bite Splint for a Hemimandibulectomy Patient: A Case Report.

Mandibular continuity defects can result in varying degrees of cosmetic disfigurement. Restoration of form and function may require surgical reconstruction of the affected area. While surgical reconstruction may improve the overall prognostic outcomes for the patient, the definitive prosthetic phase can commence only after a substantial time lag for adequate hard/soft tissue healing. This interim phase often challenges the patient's masticatory ability. The traditional reconstruction of hemimandibulectomy defects has its own limitations. This case report describes the fabrication of a 3D-printed bite splint for a patient with limited mouth opening and significant malocclusion due to surgical over-correction. The prosthesis given served as an appliance to improve the masticatory ability of the patient.

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.

Effect of masticatory training using confectioneries on oral function in elderly patients - A randomized controlled trial.

Background/purpose: The number of patients with oral hypofunction is increasing with the aging of the population, and such hypofunction increases their risk for dysphagia and malnutrition. The purpose of this study was to measure the hardness of commercially available confectioneries, select a confectionery with a hardness suitable for masticatory training for elderly patients, and evaluate the effects of 1-week masticatory training on oral function (occlusal force, masticatory ability, and tongue pressure). Materials and methods: The average hardness values of 25 confectioneries were determined. Among them, one of the softest confectioneries that the patients felt as "chewable but difficult to chew" was selected as the training confectionery for each patient. The patients in the training group continued training, which involved eating of approximately 5 g of one selected confectionery daily for 7 days. The patients in the control group did not undergo any training. Oral function (occlusal force, masticatory ability, and tongue pressure) on the first day and after 7 days was evaluated and compared between the groups. Results: The occlusal force of the patients in the training group increased significantly. However, their masticatory ability and tongue pressure did not change significantly. Conclusion: Patients aged 65 years and older underwent masticatory training, which involved eating of a confectionery with its hardness adjusted individually for a week. A significant increase in the occlusal force was observed, suggesting that masticatory training using confectioneries with a hardness suitable for each patient is effective.

Effects of food particle loss on the evaluation of masticatory ability using image analysis.

PURPOSE: To examine how particle loss affects the evaluation of masticatory ability using the image analysis method. METHODS: The subjects were divided into two groups:Y-group (healthy young adults: 10 male, 10 female; mean age 27.6 ± 1.9 years), and D-group (denture wearing older adults: 13 male, 9 female; mean age, 75.1 ± 5.3 years). Raw carrots, peanuts, and a combined test food from 5 daily food materials (mixed foods) were selected as test foods. Images of the boluses were captured and processed after the subjects freely masticated the test foods until the point of swallowing or completed half strokes of total chewing cycles. The median particle size (X50) was calculated from the data for each particle. We compared X50 calculated from all particles obtained from the masticatory bolus (as X50N) with the X50 of only selectively larger particles (as X50R). RESULTS: Significant correlations were observed between X50N and X50R (p < 0.01) determined in almost all masticatory conditions. In particular, for particle sizes of 2 mm or more, the correlation coefficient between X50N and X50R was notably strong (r > 0.75). CONCLUSION: The method of analyzing only larger particles makes it possible to evaluate masticatory ability without losing the characteristics of the original particle size distribution of the entire bolus. This finding can be applied for the evaluation of masticatory ability, especially among older adults who have difficulty retrieving the total amount of test food due to decreased activities of daily living.

Factors affecting subjective and objective masticatory function in older adults: Importance of an integrated approach.

OBJECTIVES: This study aimed to subjectively and objectively assess masticatory function and identify related factors in older adults. METHODS: From July 2017 to September 2018, we enrolled 115 healthy participants aged between 65 and 86 years. They underwent oral examination, and their stimulated salivary secretion rate and masseter muscle tone and biomechanical properties were assessed. Masticatory performance with two-colored chewing wax was objectively evaluated using the mixing ability index (MAI). Key food intake ability (KFIA) was subjectively assessed using a questionnaire. RESULTS: The MAI score was significantly associated with the number of remaining teeth (r = 0.524, p < 0.001) and the tone (r = -0.222, p = 0.017), elasticity (r = -0.242, p = 0.009), and dynamic stiffness (r = -0.265, p = 0.004) of the masseter muscles. In contrast, the KFIA score was only significantly associated with the number of remaining teeth (r = 0.450, p < 0.001). A weak association between the MAI and KFIA scores was observed (r = 0.304, p = 0.001). CONCLUSIONS: A combination of objective and subjective methods should be used to accurately assess masticatory function in older adults. In addition to physical factors such as the number of remaining teeth, properties of the masticatory muscles should be evaluated to improve the masticatory function of older adults. CLINICAL SIGNIFICANCE: In addition to dental problems, various maxillofacial and oral factors must be considered when establishing management strategies for the improvement of masticatory function in older adults.

Chewing ability and oral health-related quality of life in frail elders after new complete dentures insertion: A paired controlled clinical trial.

AIMS: To compare the effect of new complete dentures (CDs) on self-perceived masticatory ability (MA) and oral health-related quality of life (OHRQoL) in frail and nonfrail elders. METHODS AND RESULTS: Twenty completely edentulous elders were assigned to two groups: frail and nonfrail (n = 10/each). MA was evaluated using a visual analogue scale. OHRQoL was assessed with the Oral Health Impact Profile (OHIP-Edent). Variables were evaluated with volunteers wearing their old and unsatisfactory CDs. Then, a new set of CDs was manufactured and all outcomes were reassessed 2 months after the insertion. Data were analyzed by repeated measures' analyses of variance and Tukey tests. MA for lettuce and peanuts was improved (P < .05) for the frail group after new CD insertion. Psychological discomfort and handicap OHIP-Edent domain improved (P < .05) for both groups after prosthetic treatment. Before treatment, controls reported greater psychological discomfort than the frail group. Meanwhile, the handicap domain score of frail patients improved to a level similar to that of the nonfrail group after treatment. Regardless of frailty, elders showed better MA scores for most food types after treatment and decreased OHIP-Edent domain values. CONCLUSION: Self-reported MA and OHRQoL of frail elderly people were greatly improved after new CD use.

Masticatory function after bite-raising with light-cured orthodontic band cement in healthy adults.

OBJECTIVES: To evaluate the effects of bite-raising with light-cured orthodontic band cement, a method commonly used in contemporary orthodontic treatment, on masticatory function, as assessed by objective and subjective methods. MATERIALS AND METHODS: The objective evaluation of masticatory performance and subjective evaluation of masticatory ability were performed on 30 healthy volunteers (19 females and 11 males, 22.3 ± 1.56 years) with a normal occlusion. Assessment was performed before and immediately after bite-raising. The bite-raising was done by adding light-cured orthodontic band cement (3 × 5 × 2-mm width × length × height) on the palatal cusps of the upper first molars. The masticatory performance index (MPI) was calculated from chewed test food particles using a sieving method. For the subjective evaluation, the participants performed the food intake ability (FIA) test using a questionnaire with six types of food. The correlation between the evaluation methods was determined. RESULTS: The MPI and FIA scores of the participants were significantly reduced after bite-raising (P < .001). The MPI and FIA score reduction was not significantly different between females and males. No significant correlations were found between the changes in MPI and FIA scores. CONCLUSIONS: Masticatory function after bite-raising with light-cured orthodontic band cement was immediately reduced, both objectively and subjectively. However, because there was no significant correlation between the objective and subjective results, an individual may not perceive his/her decreased masticatory ability to the same degree as masticatory performance was reduced. Further study is required to evaluate the long-term adaptation to this bite-raising method.