Clinical evaluation of the gingiva around single-crystal sapphire endosseous implant after experimental ligature-induced plaque accumulation in monkeys.

This study was performed to evaluate clinical changes of the gingiva with plaque accumulation around the single-crystal sapphire implant. Four implants were inserted into mandibular and maxillary edentulous regions, and the superstructure was inserted 1 month after insertion of the implants in each of nine monkeys. Plaque control was maintained for 3 months after insertion to set up the baseline. Plaque was allowed to accumulate on one side by placing the ligature around the implant and natural teeth without any plaque control, and on the other side plaque control was continued for 9 months. Both the implant and natural teeth on the ligature side showed a significant increase in the clinical parameters of plaque index, gingival index, and probing depth. No significant difference was obtained between the implant and natural teeth. These findings indicate that plaque control is of great importance for maintaining the health of peri-implant gingiva.