Purpose：To demonstrate the increase of tongue pressure with palatal augmentation prostheses（PAP）.

　Method：Maximum tongue pressure or swallowing tongue pressure before and after insertion of PAP were investigated in 17 medical facilities. Maximum tongue pressure was evaluated in 51 swallowing disorder patients before and after insertion of PAP and after using PAP. Among these patients, 23 were classified into the structural disorder group including oral cavity cancer and cleft patients, and 28 into the functional disorder group including stroke and neurological disease patients. Swallowing tongue pressure was measured in another 29 dysphagia patients before and after insertion of PAP.

　Results：The maximum tongue pressure was increased with PAP in the structural disorder group（before：9.6±8.8 kPa, after：16.4±10.3 kPa, using PAP：20.7±11.2 kPa)(p＜0.01）. The immediate change of the maximum tongue pressure before and after insertion of PAP was strongly positively correlated with the longitudinal change before and after using PAP（r＝0.81, p＜0.01）. The same result was seen in the functional disorder group（before：12.1±7.0 kPa, after：15.5±8.0 kPa, using PAP：18.7±7.7 kPa)(p＜0.01）. The immediate change was moderately positively correlated with the longitudinal change（r＝0.51, p＜0.01）. Furthermore, the swallowing tongue pressure was increased with PAP（before：3.0±3.5 kPa, after：11.8±9.2 kPa)(p＜0.01）.

　Conclusion：Both the maximum tongue pressure and the swallowing tongue pressure were increased by inserting PAP. Also, maximum tongue pressure continuously increased while using PAP.

　Antiresorptive agents such as bisphosphonate or denosumab have been widely used for patients with osteoporosis or bone metastasis from malignant tumors, but medication-related osteonecrosis of the jaw（MRONJ）sometimes occurs. A retrospective study was conducted on the treatment and prognosis of MRONJ in patients over 80 years old. One hundred and eighty patients（66 patients were 80 years or older and 114 under 80）in three hospitals were enrolled in the study. Differences of background factors, treatment methods, and prognosis between the two age groups were analyzed by Fisherʼs exact test, one-way ANOVA, Kaplan-Meier method, log rank test, and Cox proportional hazard model. Patients over 80 years old had osteoporosis more frequently with longer administration of antiresorptive agent. Most patients underwent surgical treatment in both age groups, and no differences were found in cure rate of the two groups. Three variables of primary disease（osteoporosis/malignant tumor）, treatment method（surgical/conservative）, and periosteal reaction by preoperative CT examination were independent risk factors related to the cure rate, but old age did not influence the treatment outcome. These findings suggest that surgery should be the standard treatment for MRONJ regardless of age, and that a good outcome is expected as young people.