Page 16 - Peri-implant health: the effect of implant design and surgical procedure on bone and soft tissue stability

CHAPTER 1
microthreaded implants compared to non-microthreaded implant.32-35 However, most of the aforementioned studies did not control for other implant design factors. Moreover, the compared implants differed in more than one confounding factor, potentially biasing the outcome of the study.
■ SITE-SPECIFICFACTORS
Other factors that could influence peri-implant bone stability are site-specific factors. The effect of peri-implant mucosal tissue thickness on peri-implant bone stability has been described in animals. These studies suggested a certain minimum width of peri-implant mucosa as a prerequisite, allowing a stable soft tissue attachment.36 Studies in humans confirmed this finding and concluded that a soft tissue thickness of 2 mm or less resulted in crestal bone loss up to 1.45 mm37. More recently, Vervaeke and co-workers concluded that the initial bone remodeling was affected by soft tissue thickness.38 Furthermore, they suggested that an unforeseen exposure of the implant surface during initial bone remodeling should be avoided by adapting the vertical position of the implant during surgical placement in relation to the available preoperative soft tissue thickness. In the light of the hype that currently exists around peri-implantitis, it has been questioned whether the early exposure of implant surfaces to soft tissues could hamper peri-implant health or may pose a risk for the future development of peri-implantitis. Galindo-Moreno and co-workers concluded in an 18-month study that early implant surface exposure was predictive for additional bone loss.39 Another clinical study, examining 105 implants in 21 patients, concluded that initial bone loss and surface exposure at 2 years of function was identified as a predictor for further bone loss after 10 years of function.40
■ ORALHEALTH-RELATEDQUALITYOFLIFE
While there are many patient-related, implant-design, and site-specific factors that affect the success of implant treatment. The success of an implant treatment should also be determined by the improvement in Oral Health-Related Quality of Life (OHRQoL).41 To measure this improvement, the Oral Health Impact Profile-14 (OHIP-14) questionnaire is a widely used tool. The tool consists of a questionnaire
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