Single-implant Overdentures Improve Mastication and OHRQoL in Long Term

Objectives: Oral rehabilitation by implant-supported dental prostheses can improve masticatory function and quality of life related to oral function (OHRQoL) in elderly people. However, it is unknown the long term effect of single-implant overdentures (SIO) on such variables, which stand for the objective of this paired clinical study.
Methods: Fifteen elderly individuals (mean age = 68.27 ± 4.77 years) with decreased residual bone height were included. They received a set of new conventional complete denture and after 2-months, masticatory performance, masticatory efficiency, maximum bite force, masseter thickness, chewing movements and OHRQoL were assessed. Sequentially, mandibular complete dentures were converted into a SIO, by inserting one external hexagon implant. Variables were reevaluated 2, 12 and 24-months after SIO installation. Masticatory performance and efficiency were determined with the sieving method, while maximum bite force was evaluated by pressure sensors. Masseter thickness was measured by ultrasonography, chewing movements were assessed by a kinesiograph device, and the Geriatric Oral Health Assessment Index (GOHAI) was applied to measure the OHRQoL. Data were submitted to ANOVA and Student's t test (p < 0.05).
Results: Masticatory performance and efficiency improved (P < 0.05) after 2-months of SIO insertion and remained steady over time. Maximum bite force and masseter thickness increased (P < 0.05) until 12-months of SIO evaluation, without changes at 24-months. In contrast, opening time decreased (P < 0.05) 12-months after SIO installation. GOHAI index were higher (P < 0.05) using SIO than conventional CD.
Conclusions: Most of masticatory function parameters, such as masticatory performance and efficiency, maximum bite force and masseter thickness increased and remained higher until 24-months follow-up. OHRQoL also enhanced after SIO already at 2-months.