The effect of tooth loss on the temporomandibular joint space: A CBCT study

OBJECTIVE

The tooth loss has a significant impact on the positioning of the condyle in the glenoid fossa and joint spaces of the temporomandibular joint (TMJ). The aim of this study was to assess the association between tooth loss and TMJ spaces using cone beam computed tomography (CBCT) images.

MATERIALS AND METHODS

This retrospective investigation involved the evaluation of CBCT images of the bilateral TMJs in a cohort of 111 individuals, comprising 68 males and 43 women. The dentition of the patients was categorized into three categories, including A (65.4%), B (19.1%), and C (16.4%), based on the Eichner index. Anterior, superior, and posterior joint spaces were then measured in sagittal views. The Kruskal-Wallis test and Mann-Whitney test were employed to identify significant differences among the three Eichner groups.

RESULTS

The findings of the present study suggested that there was no statistically significant variation in the anterior joint space among different Eichner groups within the general population (p = .781). Nevertheless, the superior and posterior joint spaces exhibited statistically significant alterations, as indicated by p-values of .039 and .010, respectively. It was detected that condyles were positioned inferiorly and posteriorly in group C when compared to groups A and B.

CONCLUSION

The present study indicated that greater loss of tooth-supporting zones is associated with posterior and inferior displacement of condyles. Understanding these relationships helps emphasize how crucial it is to replace missing teeth to enhance occlusion support and, in turn, stop the progression and further deterioration of temporomandibular disorders.

Quantitative analysis of masticatory muscle changes by Eichner index using diffusion-weighted imaging

OBJECTIVES

Diffusion-weighted imaging (DWI) provides quantitative functional information about the microscopic movement of water at the cellular level. However, few reports have quantitatively evaluated histological changes in masticatory muscles due to changes in occlusal relationships using DWI. This study aimed to assess the changes in masticatory muscles by Eichner index using DWI.

METHODS

We analyzed magnetic resonance imaging (MRI) studies of 201 patients from November 2017 to April 2018. Each Eichner index group, age, and sex were used as criterion variables, and the average apparent diffusion coefficient (ADC) values of the masticatory muscles were the explanatory variable. The mean ADC value differences were analyzed in each Eichner index group. We analyzed the data using the Kruskal-Wallis test and post hoc Mann-Whitney test with Bonferroni adjustment multiple regression analysis with Shapiro-Wilk test and Spearman's correlation coefficients. P < 0.05 was considered statistically significant.

RESULTS

The mean ADC values of each Eichner classification group were significantly different, with the lowest value in group C (P < 0.001). There was a negative correlation between the ADC value of the masseter, lateral pterygoid muscle, and age (P < 0.001). There were significant differences between the sex groups (P < 0.001).

CONCLUSIONS

ADC values of masticatory muscles were significantly different in the Eichner index groups. The ADC values of masticatory muscles may be useful for the quantitative evaluation of the masticatory muscles affected by the occlusal state.

Masticatory performance and other oral functions in community-dwelling elderly patients without posterior occlusal support by natural teeth

PURPOSE

To evaluate masticatory performance (MP), maximum occlusal force (MOF), maximum tongue pressure (MTP) and oral diadochokinesis (ODK) among community-dwelling elderly patients without posterior occlusal support.

METHODS

This study enrolled community-dwelling elderly patients (≥65 years old) who belonged to Eichner A, B4, C1, C2, and C3. Each oral function was statistically compared among groups. Correlations between MP and other variables were examined in Eichner B4 and C patients.

RESULTS

MP and MOF values in Eichner B4 and C patients were significantly lower than in Eichner A patients. There were significant differences in MTP values between Eichner "A and C2, C3", and "B4 and C2, C3". ODK in Eichner C patients showed significantly lower values compared to Eichner A patients in general. Although there were statistically significant correlations of MP with age, the number of remaining teeth and all oral functions were identified, and multiple regression analysis indicated that MOF and MTP were independently related to MP.

CONCLUSION

Oral functions in Eichner B4 and C patients were lower compared to Eichner A patients. MP was significantly correlated with MOF and MTP in elderly patients without posterior occlusal support, suggesting the importance of rehabilitation of MOF and MTP in MP.

The Significance of Posterior Occlusal Support of Teeth and Removable Prostheses in Oral Functions and Standing Motion

The purpose of this study was to evaluate the effect of posterior occlusal support of natural teeth and artificial teeth on oral functions and standing motion. Patients who had been treated with removable prostheses were enrolled as the subjects. Their systemic conditions (body mass index (BMI) and skeletal muscle mass index (SMI)) were recorded. The subjects were classified into two groups according to a modified Eichner index: B1-3 (with posterior occlusal support) and B4C (without posterior occlusal support). Maximum occlusal force (MOF), masticatory performance (MP), and standing motion (sway and strength) were evaluated for cases with and without removable prostheses. There were no significant differences in BMI and SMI between the B1-3 group and the B4C group. The subjects with removable prostheses demonstrated significantly higher values in MOF, MP, and sway and strength than the subjects without removable prostheses. The comparison of oral functions between the B1-3 group and the B4C group revealed that the positive effect of posterior occlusal support of natural teeth and removable prostheses and the significant positive effects of posterior occlusal support on standing motion were partly observed in these comparisons. Posterior occlusal support of natural teeth and even of removable prostheses may contribute to the enhancement of oral functions and standing motion.

Dentition, nutritional status and adequacy of dietary intake in treatment naïve head and neck cancer patients

OBJECTIVES

To examine the relationship of reduced numbers of occluding teeth and dietary intake (DI), nutrition impact symptoms (NIS), and weight loss (WL) in head and neck cancer (HNC) patients.

METHODS

As a part of the standard of care, treatment-naïve HNC patients (n = 104) completed dental evaluation (number of teeth, total anterior/posterior occlusal teeth, Eichner Index (EI) classification), WL, DI questionnaire and HNC Symptom Checklist©. Descriptive statistics (Kruskal-Wallis, Fisher-exact, χ² tests) and (uni-) multi-variable logistic regression.

RESULTS

Overall, 42, 45 and 13% of patients were in EI-class A, B and C with a median of 8, 3, and 0 total posterior occlusal teeth. EI-class B/C patients were older, more likely to have impaired DI (OR = 3.88; 95%CI:1.63-9.26; P = 0.002) and reported interference with DI by 11 NIS (p < 0.05). DI was, however, reported as unimpaired in 77, 49 and 39% of patients in EI-class A, B and C, respectively. The subset of EI-class B/C patients with impaired DI, had more NIS interference with DI (P < 0.05; difficulty chewing, pain, early satiety, lack of energy); EI-class C patients additionally had dry mouth, thick saliva and dysphagia (P < 0.05). In logistic regression, EI-classes B/C patients with reduced (vs unimpaired) DI were more likely to have ≥5% WL (OR = 10.1; 95%CI:2.0-50.0), higher NIS interference (range OR 4.3-10.7).

CONCLUSIONS

More than half of these HNC patients had reduced numbers of occlusal teeth or were edentulous. EI-class B/C patients did not necessarily have impaired DI, however the combination of EI-class B/C and a constellation of NIS, associated with reduced DI.

CLINICAL SIGNIFICANCE

Treatment naïve head and neck cancer (HNC) patients with reduced occlusal and masticatory performance (Eichner Index B/C) and reduced dietary intake are at high risk for weight loss. Identifying HNC patients at risk may improve their oral health, dietary intake and reduce their risk of weight loss.

Loss of Posterior Occluding Teeth and Its Association with Protein-Micronutrients Intake and Muscle Mass among Thai Elders: A Pilot Study

Contact between upper and lower posterior teeth is crucial for chewing. However, the influence of posterior occluding teeth loss on protein intake and muscle mass was unclear. This cross-sectional study compared consumption frequency of protein food, amount of protein and relevant micronutrient intakes and muscle mass indices among older adults with different Eichner indices (EI) of posterior occluding teeth loss. Ninety Thai healthy adults were divided into three groups (N=30 each) according EI with statistically comparable characters. Food frequency questionnaire, 4-days diet record, and bioelectrical impedance analysis were used for outcome measurement. Our findings suggested that loss of posterior occluding teeth on both sides was associated with less frequent consumption of meat, nut, egg, fish and dairy products, inadequate intakes of protein (< 0.8 g/kg body weight), iron and vitamin B12, and reduced muscle mass indices in older adults. Future large-scale cohort studies are warranted to confirm these findings.

Impact of occlusal support and perceived chewing ability on oral health-related quality of life among patients attending a private dental institution in India

Purpose:

Presence of functional tooth units is essential for preserving masticatory function among individuals. Representing the essence of health promotion practice, demand to measure varied evaluation outcomes is highlighted.

Aim and Objectives:

(1) To assess the influence of occlusal support and perceived chewing ability on oral health-related quality of life (OHRQoL) among adults attending a private dental institution in Mangalore. (2) To evaluate occlusal support using Eichner index (EI), perceived chewing ability using a self-administered questionnaire and OHRQoL using Oral Health Impact Profile-14 (OHIP-14).

Materials and Methods:

Overall, 300 adults attending a private dental institution in Mangalore were included. EI was used to group participants into three groups. The chewing ability was assessed using a questionnaire on perceived difficulty while chewing eight common foods. OHRQoL was measured employing OHIP-14. Perceived general and oral health status and demographic information were collected.

Results:

The mean perceived chewing ability score was 12.98 ± 6.2 and the mean total OHIP score was 9.23 ± 8.9. EI showed a significant relation with perceived chewing ability, OHIP, and perceived general health status (P < 0.05). Perceived chewing ability and OHIP demonstrated a significant correlation (r = 0.31, P < 0.001). Age, gender, education, occupation, monthly income, family income, and number of family members demonstrated a significant association with EI (P < 0.05). Binary logistic regression analysis revealed that EI, perceived chewing ability, and perceived oral health emerged as significant predictors of OHRQoL (P < 0.05).

Conclusions:

Occlusal support was significantly associated with perceived chewing ability, OHRQoL, and perceived general health status.