内部維持機構型オッセオインテグレーテッドインプラントの埋入初期動揺度変化に関する臨床的検討

抄録

Conventional osseointegrated-type implants are considered to require a 3-5 month nonweight-bearing period after implantation. There are few reports regarding mechanical observations of the osseointegration processes of implants, although recently there have been some reports on attempts to reduce the nonweight-bearing period as a result of issues such as esthetics, occlusion, and manducation. Here, we report the results of measurements of initial tooth movement after implantation, and clinical observations of mechanical changes.
The subjects consisted of 63 CAMLOG implants which were grafted at our department from January 2004 to December 2006, and were measured once every week after implantation using a Periotest device. Gingivaformers with 6 mm gingival heights were screwed into the implants, PT values were measured three times at a height of 5 mm using a PT handset, and the average values were calculated.
The average PT value was -3.83 at the time of implant. This value increased to -3.14 after two weeks, then decreased over time to a value of -4.14 after 6 weeks.
Our results show that the PT values of osseointegration implants demonstrate an overall downward tendency. However, there is a period during which PT values temporarily increase and mechanical instability occurs. As PT values are slightly affected by sex, age, and site specificity, it was inferred that it is desirable to reduce nonweight-bearing periods by taking into consideration stability measurements obtained using mechanical test devices such as the Periotest.