OBJECTIVE: Although poor oral health has been a potentially modifiable risk for mortality, the precise association between functional tooth units (FTUs) and premature death as well as the underlying mechanisms remains unclear.
METHODS: This study used data from the National Health and Nutrition Examination Survey (NHANES) 2009-2018. Mortality details were obtained from the National Death Index (NDI). The number of FTUs was defined as pairs of opposing natural and artificial teeth in the premolar and molar area. Weighted logistic regression models were employed to assess the relationship between FTU and premature death. Demographic characteristics, lifestyle habits, and disease histories were adjusted as confounding factors. The propensity score matching (PSM) was conducted to further assess the association between FTU and premature death. Mediation analyses were conducted to assess the role of diet-related diseases in the association between FTU and premature death.
RESULTS: The analysis included 4169 individuals aged between 60 and 74 years. Participants with 0 ≤ FTUs ≤ 3 had a significantly higher odds of premature death compared to the 10 ≤ FTUs ≤ 12 group (OR = 2.142, 95% CI 1.091-4.208). After missing data imputation, 0 ≤ FTUs ≤ 3 was still significantly associated with increased odds of premature death (OR = 2.115, 95% CI 1.125-3.975). The relationship between 0 ≤ FTUs ≤ 3 and reference group persisted (OR = 2.196, 95% CI 1.296-3.721) after PSM analyses. For mechanism, mediation analysis showed that diet-related diseases, including diabetes and hypertension, partially mediated the association between FTU and premature death with proportions of 5.089% and 8.437%, respectively.
CONCLUSIONS: The findings revealed a link between impairment of masticatory function and a heightened odds of premature death among older adults. Notably, 0 ≤ FTUs ≤ 3 is significantly correlated to premature death among this demographic, with diabetes and hypertension partially mediating the effect of FTU on premature death. Further longitudinal studies are required to validate the findings.

OBJECTIVE: Depression is prevalent among older adults. Although the number of missing teeth is considered to be associated with depression, the relationship between masticatory function, which is usually indicated by functional tooth units (FTUs), and depression in older adults remains unclear.
METHODS: This study used data from the National Health and Nutrition Examination Survey (NHANES) 2009-2018. The number of FTUs was defined as pairs of opposing natural and artificial teeth. Depression was accessed using the Patient Health Questionnaire (PHQ-9), and participants who scored ≥10 on PHQ-9 were diagnosed with depression. Logistic regression analyses, propensity score matching (PSM) analyses and subgroup analyses were conducted to assess the association between FTU and depression.
RESULTS: The analysis included 5764 individuals over 60 years. An association between FTU and the risk of depression among older adults was detected (odds ratio [OR] = 0.951, 95% confidence interval [CI] 0.915-0.989), suggesting protective roles of more FTUs. Significant increase in the risk of depression in 0 ≤ FTUs ≤ 3 was observed compared with 10 ≤ FTUs ≤ 12 (OR = 1.819, 95% CI 1.157-2.858). However, no significant increase in the risk of depression in 4 ≤ FTUs ≤ 9 was found. After PSM, significant increase in the risk of depression in 0 ≤ FTUs ≤ 3 was still detected compared with 4 ≤ FTUs ≤ 12 (OR = 1.484, 95% CI 1.030-2.136). Subgroup analyses demonstrated consistent results in all subgroups, except for individuals aged 76-80 and drinking regularly.
CONCLUSIONS: The findings suggested the association between impaired masticatory function and the risk of depression among older adults. Longitudinal studies are needed to elucidate the role of masticatory function impairment in the development of depression further.

OBJECTIVE: Emerging evidence points to a two-way relationship between periodontitis and dietary choices and, thus, nutrition. This study aimed to assess the potential cause-effect relationship between the periodontitis stage, loss of functional tooth units (FTUs), masticatory function, and intake of different food groups using path analysis.
METHODS: A single calibrated examiner determined the periodontitis stage of a consecutive sample of 241 Chinese subjects reporting for tooth replacement. Their masticatory function was quantified by the mixing ability of a two-colour chewing gum. Validated food frequency questionnaires were used to calculate the intake of 33 food group items by an experienced calibrated rater. After verification of assumptions, visual structural equation modeling was performed with Amos 23. The consistency of results and the potential modifying effect of age were assessed in 9043 subjects from the NHANES database.
RESULTS: Highly significant models were constructed using periodontitis stage and age as exogenous factors. Periodontitis stage diagnosis significantly affected the number of posterior FTUs and oral health-related quality of life (OHRQoL, path coefficient [PC] = -0.55 and -0.20, p < .05, respectively). In the model, FTUs also had an independent effect on OHRQoL (PC = 0.23, p < .05). FTUs determined the level of masticatory function (PC = -0.38, p < .05), which in turn affected vegetable intake but not fruit or meat intake (PC = -0.18, p < .0.5, PC = 0.06, NS and PC = 0.11, NS, respectively). The effect of age was significant for vegetable and meat intake and was also correlated with periodontitis stage diagnosis. Analysis of the NHANES database confirmed the negative impact of periodontitis on the number of occluding pairs and vegetable consumption for the 18-44, 45-60 and >60 age groups.
CONCLUSIONS: Periodontitis showed a potential cause-effect pathway affecting vegetable intake across cultures and age groups. The size of the effect is potentially of clinical and public health significance. Additional studies, including intervention trials, are required to test this potential mechanism linking oral health to nutrition.

OBJECTIVE: This study was designed to determine the efficacy of a traditional complete denture and a biofunctional prosthetic system of a complete denture, and risk factors affecting their efficacy.
METHODS: A retrospective analysis was performed on 95 patients with total dentition loss admitted to our hospital from January 2015 to June 2022. Among them, 45 patients who received traditional dentures were assigned to a control group, and the other 50 who received a biofunctional prosthetic system with complete dentures were assigned to an observation group. The clinical efficacy was compared between the two groups before and after treatment, and the masticatory function indexes and comfort scores of the two groups were also compared. Logistics regression analysis was conducted to analyze the risk factors affecting the efficacy of patients.
RESULTS: The observation group showed a higher total effective rate than the control group (P<0.05). After treatment, the observation group showed notably higher masticatory efficiency and absorbance of masticatory substances than the control group (P<0.05). In addition, the denture tenderness point in the observation group was notably lower than that in the control group (P<0.05). After treatment, the observation group had notably higher scores in General Comfort Questionnaire than the control group (P<0.05). Moreover, according to Logistics regression analysis, older age, dentition loss caused by tooth defect, smoking history and traditional denture restoration were independent risk factors for ineffective treatment.
CONCLUSIONS: The biofunctional prosthetic system of complete dentures can better improve the masticatory function and enhance the comfort of patients with total dentition loss, and with good efficacy.

BACKGROUND: Decreased masticatory function contributes to malnutrition in the elderly. The purpose of our study was to explore whether the masseter muscle is involved in masticatory function in older adults and to help determine if the masticatory function of the elderly can be improved by exercising the masseter muscle.
METHODS: Random sampling was adopted in our research, and a total of 413 older adults from 9 nursing homes in China were recruited from March 10 to June 12, 2022. The thickness and echo intensity of their masseter muscles were assessed using ultrasound. Masticatory function was measured using a color-changing chewing gum, and the change of α* before and after chewing (Δα*) was defined as masticatory function. If Δα* <14.2 in males or <10.8 in females was masticatory dysfunction. Their number of molar occlusal supports (MOSN), comorbidity, oral diadochokinesis (ODK), maximum tongue pressure (MTP), and calf circumference (CC) were evaluated. Multiple linear regression analysis was performed to identify the factors independently associated with the masticatory function.
RESULTS: Of the 413 older adults, 179 (43.3%) had masticatory dysfunction. The average thickness of the masseter muscle between contraction and relaxation was 1.3 mm (range, 0.7-2.0 mm). The thickness of the masseter muscle and ODK decreased with age, while the echo intensity of the masseter muscle increased. The results of the multiple linear regression analysis showed that dynamic change in the thickness of the masseter muscle between contraction and relaxation (β=0.085; P=0.049), MTP (β=0.147; P=0.001) and MOSN (β=0.349; P<0.001), brushing teeth ≥2 times/day (β=-0.187; P<0.001), and CC (β=0.135; P=0.002) were independent factors affecting masticatory function.
CONCLUSIONS: We found that masticatory dysfunction was prevalent among older adults in nursing homes in Southwest China, and the dynamic change in the thickness of the masseter muscle between contraction and relaxation was positively correlated with masticatory function. This result suggests that we can improve the masticatory function of the elderly by increasing the thickness of the masseter muscle between contraction and relaxation (e.g., by exercising the masseter).

There is a global increase in the older population. Unfortunately, dental conditions in the older population can sometimes be poor as a result of worsened physical conditions and the cumulative damage caused by dental diseases in the past. Many suffer from oral diseases such as dental caries and periodontal disease but receive no regular dental care. Oral conditions and systemic problems are interrelated. Chronic medical problems and polypharmacy are common among them. These conditions may lead to xerostomia with or without a decrease in saliva output. Additionally, many older adults have deteriorated masticatory function associated with physical health issues such as frailty. Preventive measures are crucial to stop oral diseases from progressing and the replacement of missing teeth is needed when masticatory function is impaired. Older adults also suffer a higher risk of oral cancer because of their less resilient but more permeable oral mucosa. With the increasing need for elderly dental care, dentists should equip themselves with knowledge and skills in geriatric dentistry. They should help older adults to develop and maintain the functional ability that enables well-being in older age. This communication article aims to discuss the relevant medical conditions, common dental diseases, and dental care for older adults.

OBJECTIVE: The aim of this study is to demonstrate if dental implant restoration can improve the clinical efficacy, masticatory function and comfort in patients with dentition defects.
METHODS: The clinical data of 90 patients with single tooth loss treated in Yuyao People\'s Hospital of Zhejiang Province from May 2018 to May 2020 were analyzed retrospectively. The patients were enrolled and divided into two groups. The control group (CG; n=45) was intervened by traditional fixed partial denture (FPD) restoration, and the observation group (OG; n=45) was treated with dental implant restoration. The clinical efficacy was evaluated, and amelioration of tooth-related indexes and clinical indicators 2 years after treatment were observed. The improvement of masticatory function and comfort scores were compared. The adverse reactions during treatment were recorded, and patients\' satisfaction with the treatment was calculated. Logistic regression was performed to assess the independent risk factors for inefficacy of the treatments.
RESULTS: After treatment, the OG presented with lower gingival index, plaque index and sulcus bleeding index.

The aim of this study was to retrospectively assess bone volumes, healed ridge topography and possibility to plan prosthetically guided implants (PGI) at least 6 months after extraction or exfoliation of first molars as a consequence of terminal periodontitis (EEFMP).
45 subjects with stage III-IV periodontitis providing 74 extraction sites (maxillary = 51 and mandibular = 23) were included. The degree of residual periodontal support on each root was assessed by combining periodontal and radiographic data. Digital planning of PGI with 4.8/4.1 mm diameter, 8 mm long, root-form dental implant and need for bone augmentation (BA) were performed using CBCT with a radiographic stent. Possibility of standard implant placement (STANDARD) and need for simultaneous or staged BA were assessed.
Planning PGI placement was possible in all cases. For a 4.8 mm diameter implant, STANDARD was possible in 37.8% of the sites, 33.8% required BA at the time of implant placement, and 28.4% required staged BA before PGI. The use of 4.1 mm rather than 4.8 mm diameter implant allowed STANDARD in an additional 8.1% of cases that originally required simultaneous BA/osteotome sinus floor elevation (OSFE). The level of periodontal bone loss did not predict the complexity of implant placement, but significant differences were observed comparing maxillary with mandibular sites.
PGI planning at sites with first molar loss due to terminal periodontitis is possible but poses great challenge to rehabilitation, often requiring advanced augmentation procedures and sinus augmentation.