[A case of occlusal support loss in the molar region due to distal extension missing of the left of the upper and right of the lower jaws].

PATIENT A 74-year-old woman visited our hospital with a chief complaint of masticatory dysfunction due to upper left molar denture breakage and poor retention of upper and lower dentures. The cause of the denture breakage was a lack of clearance, and that of denture instability was the unilateral design in the upper jaw, and breakage of the indirect retainer in the lower jaw. The treatment plan was set to securing the denture strength and bracing via a bilateral design. DISCUSSION Stability was improved by bilateral design. Ensuring clearance and subsequent place on the dentures may have secured the strength. CONCLUSION The ability of mastication was improved by the new dentures. Regarding the strength, no breakage of the dentures occurred during the follow-up period, indicating that prosthetic treatment was appropriate.