Purpose：The purpose of this study was to evaluate the assessment of poor oral hygiene using the ATP swab test.

　Method：A total of 102 consecutive elderly outpatients aged ≥65 years who visited for maintenance were enrolled between October 2019 and April 2020. The evaluation of poor oral hygiene included measurements of：Tongue Coating Index（TCI）, number of bacteria by a rapid oral bacterial detection device（Bacterial Counter DU-AA01NP-H；Panasonic Health Care, Japan）, and amount of ATP+AMP by the ATP swab test（Lumitester；Kikkoman, Japan）. The specimens were a gargle solution rinsed with 10 mL of water for 5 seconds as soon as the patients came to the hospital or a cotton swab wiped on the tongue dorsum. The subjective assessment of hygiene of the oral mucosa and dentures was rated on a 5-point scale.

　Results：In the assessment of tongue dorsum hygiene, the number of bacteria and the amount of ATP+AMP were significantly correlated with TCI. There was also a significant correlation between the number of bacteria and the amount of ATP+AMP.

　Conclusion：The results of this study suggested that the ATP swab test might be used to objectively assess overall poor oral hygiene, including food residues.

　Poor oral function（oral frailty）leads to the need for nursing care if left untreated. Therefore, the prompt detection and treatment of oral frailty are critical.

　In this study, a total of 52 patients（23 men, 29 women；age［mean±SD］, 71.0±12.4 years old）of a community dental clinic in Saga were enrolled. Factors related to the difference between subjective awareness of oral frailty and examinations of oral hypofunction were evaluated.

　The examinations revealed oral hypofunction in 17（32.7％）patients, 12（23.1％）of which were unaware of oral frailty.

　Our data suggested that oral hypofunction is related to age, nursing care level, occlusal support area, and physical frailty；however, the factors related to the difference between subjective awareness of oral frailty and examination of oral hypofunction could not be clarified.

　The concordance rate between the subjective symptoms for swallowing function and the examination results obtained by the Seirei dysphagia screening questionnaire or repetitive saliva swallowing test（RSST）was different in each group.

　Therefore, both objective and subjective evaluations such as RSST and the Seirei dysphagia screening questionnaire, respectively, should be performed when examining swallowing function. Further consideration in this regard is needed in the future.

　Objective：Many factors, such as jaw defects, reconstruction methods, and present tooth condition, are considered to affect the success or failure of prosthetic recovery from deterioration of oral function in postoperative mandibular tumors. However, the factors that influence the stability of dento-mandibular prostheses with defective jaws have not been investigated in detail so far. Therefore, in this study, we investigated factors related to prosthesis stability in elderly patients using dento-mandibular prostheses with defective jaws who had undergone surgery for mandibular tumors.

　Subjects：Between 2014 and 2018, at Hokkaido University Hospital, we observed the postoperative course of 10 patients, aged 65 years or older, who had mandibular tumors and wore a dento-mandibular prosthesis with defective jaws.

　Methods：Dento-mandibular prosthesis stability was determined using an evaluation method based on the Kapur scale for evaluating dentures. Score 2 was considered to indicate “Good” stability, and Scores 0 and 1 were considered to indicate “Poor” stability. The subjects were divided into two groups：the Good Stability group（seven subjects）and the Poor Stability group（three subjects）, and a comparative examination of factors related to dento-mandibular prosthesis stability was conducted.

　Results：No significant differences were found in all factors between the two groups. The effectiveness of each factor related to the quality of dento-mandibular prosthesis stability was calculated, and it was found that the effects of dento-mandibular prosthesis type, denture space, and flap mobility and incompressibility were markedly large. A certain level of effect was also observed for number of abutment teeth, number of current mandibular teeth, age at which the dento-mandibular prosthesis was fitted, and gender.

　Conclusion：It was shown that the stability of a dento-mandibular prosthesis fitted after mandibular tumor surgery was greatly affected by dento-mandibular prosthesis type, denture space, and flap mobility and incompressibility. However, since the number of patients in this study was small, the number of cases may need to be increased in future studies.