Long-term follow-up of a patient with Parkinson's disease under nursing care after replacement of fixed implant-supported prostheses with an implant overdenture: a case report.

Background: In older patients with progressive neurodegeneration, replacing fixed implant-supported prostheses (FIP) with implant overdentures (IOD) has been proposed to prevent future mucosal injury and create an oral environment that is easier for caregivers to clean. However, there have been no reports on the progress after replacing FIP with IOD. In this report, we present the progress of an older patient with Parkinson's disease in whom FIP was replaced with IOD.

Case presentation: An 81-year-old male patient with Parkinson's disease presented to our outpatient clinic with bruxism and crossbites. FIPs, with five Brånemark system implants, were placed in the bilateral lower molars. The FIP was replaced with an IOD with two locator attachments to create an oral environment that was easier for caregivers to clean and allow easy recovery of masticatory function if residual teeth were fractured in the care environment. As his systemic condition deteriorated, treatment was changed from outpatient to in-home visits. During dental care visits, professional oral cleaning and denture repair were continued, and good nutritional status was maintained. However, the patient developed cholecystitis and was hospitalized. During hospitalization, gastrostomy was performed because he developed aspiration pneumonia. After discharge from the hospital, the patient remained in bed all day and could not wear an IOD, resulting in buccal mucosa ulceration due to abrasion of the locator abutment. We decided to replace the abutment with cover screws; however, not all the implants could sleep submucosally. Although regular oral cleaning was resumed, new ulcers developed even when cover screws were installed. Additionally, swelling and drainage were observed at the peri-implant mucosal site where peri-implantitis had once occurred during an outpatient visit. The patient was readmitted to the hospital for a urinary tract infection, and subsequent visits were abandoned.

Conclusions: By replacing FIP with IOD in an older patient with Parkinson's disease, we addressed a barrier to caregiver-provided oral management. The removable prosthesis facilitated smooth oral care by caregivers and functional recovery in the event of trouble with residual teeth. However, it could not completely avoid the recurrence of buccal mucosal ulcers or peri-implantitis.