The aim of this study was to obtain objective and standardized information on masticatory function and patient satisfaction following second molar single implant therapy.

Twenty adult patients, who had restored second molar single implants more than 1 month before the study, were enrolled in this study. All patients received a chewing test using peanuts before and after insertion of the implant prosthesis, with a questionnaire and visual analogue scale (VAS) to evaluate the effect of second molar single implant therapy.

This study obtained standardized information on the masticatory function objectively (e.g., P, R, X₅₀) before (Pre-insertion) and after insertion (Post-insertion) of the implant prosthesis. Masticatory performance (P) after insertion of the implant prosthesis significantly increased from 67.8±9.9 to 84.3±8.5% ( P <0.0001). With the implant prosthesis, the P value increased by 24%. The masticatory efficiency index (R) of Post-insertion is higher than that of Pre-insertion ( P <0.0001). With the implant prosthesis, the R value increased by 29%. The median particle size (X₅₀) of Post-insertion is lower than that of Pre-insertion ( P <0.0001). More than 90% of the patients were satisfied with the second molar single implant therapy from a functional point of view.

These findings indicate that a second molar single implant can increase masticatory function.