The aim of this study was to investigate the predictors of dental changes associated with long-term treatment with oral appliances (OAs) in patients with obstructive sleep apnea (OSA). This was a retrospective study to investigate Japanese patients with OSA receiving long-term treatment with OAs. Comparisons of cephalometric analysis were carried out between the initial and follow-up assessments of dental and skeletal changes. Based on dental changes, predictors that may cause side effects were investigated. A total of 64 patients (average age at start of treatment: 57.7 ± 14.2 years, 44 males) were included in this study. The average duration of treatment was 4.3 ± 2.1 years. Over the total treatment period, there was a significant reduction in overjet (OJ) (1.5 ± 1.3 mm) and overbite (0.90 ± 1.5 mm), and an increase in the lower incisor line to the mandibular plane (3.1 ± 5.4°). A larger reduction in OJ of ≥ 1 mm was associated with treatment duration, use frequency, and mandibular advancement of the OAs. In addition to these predictive factors, the number of teeth was correlated with the amount of OJ reduction. For long-term treatment with OAs, the risk of dental side effects should be considered, such as a reduction in OJ. A small number of maxillary teeth, as well as the factors associated with OAs, including treatment duration, use frequency, and mandibular advancement of the OAs, was correlated with an increased rate of OJ reduction. A commentary on this article appears in this issue on page 7.

Purpose: To review dental sleep medicine in older adults based on the literature.Study selection: This narrative review focuses on sleep physiology, common sleep disorders, and obstructive sleep apnea (OSA) in older adults and their management.Results: Sleep physiology differs between older and younger adults, with sleep disturbances occurring more frequently in older adults. The prevalence of insomnia increases in older adults due to age-related changes in sleep physiology. Insomnia, sleep-disordered breathing, periodic limb movement disorder, restless legs syndrome, and rapid eye movement (REM) sleep behavior disorder are common sleep disorders in older adults. OSA is more prevalent in older adults, and its effects on them are considered more substantial than those on younger adults. The treatment of older patients with mandibular advancement devices may be less effective and more complex owing to potential impairments in oral and dental health. Furthermore, the prevalence of edentulism in older adults is decreasing while life expectancy is increasing.Conclusions: As older adults have comorbidities that affect sleep quality, dentists should consider the effects of sleep physiology and sleep disorders in these patients. OSA may decrease the quality of life and increase the risk of developing other diseases. Therefore, dentists proposing treatment with mandibular advancement devices need to inform patients of their potential lack of efficacy and the requirement for careful follow-up owing to known and unknown side effects.

Introduction: The purpose of the present study was to clarify the relationships between the risk of malnutrition as a preliminary stage of malnutrition and overall and oral measurements for sarcopenia in older Japanese adults. Methods: Forty-five participants (79.7 ± 6.1 years) were included in the analysis. The nutrition status of the participants was assessed using the Mini Nutritional Assessment-Short Form (MNA-SF) and classified into two groups: normal and at risk of malnutrition. Overall measurements for sarcopenia in the present study were the skeletal muscle mass index, grip strength, and walking speed, while oral measurements were the cross-sectional area of the geniohyoid muscle, tongue pressure (TP), and oral diadochokinesis. Results: MNA-SF correlated with TP (r = 0.347, p = 0.019). We observed decreases of 5.7 kPa in TP and 3.9 kg/cm² in BMI in the at risk of malnutrition group. A multiple regression analysis of parameters contributing to the risk of malnutrition identified TP as an independent variable (β = 0.913, p = 0.042). Conclusions: The present results demonstrate that the risk of malnutrition is associated with TP as an oral measurement for sarcopenia, but not overall measurements for sarcopenia. Therefore, low TP may be related with the risk of malnutrition.