Peri-implant tissue score (PITS) as a measure of success, applied to 869 dental implants from a retrospective clinical study

Objective: This article presents a methodology of a comprehensive score for assessment and monitoring of dental implant success from the peri-implant tissue perspective. It involves only standard and minimally invasive techniques accessible to general dental practices, without the need for special equipment. Methods and Materials: The proposed score methodology combines existing consensual global knowledge regarding aspects of dental implant success with the standard examination tools accepted for regular recall assessment. The score is a sum of five three-grade parameters: bone level, peri-implant inflammation, amount of attached mucosa, tissues recession (ie, exposure of implant components to intraoral environment), and the horizontal buccal profile of the alveolar process. The name peri-implant tissue score (PITS) is derived from the intended primary use of monitoring the state of implants and the surrounding hard and soft tissues. With its emphasis on buccal-aspect tissues, the score is designed to aid the detection of early signs of tissues deterioration. Results: The use of the score is demonstrated on a sample pool of 869 retrospectively evaluated implants with airborne-particle-abraded, acid-etched surfaces with time in service from 0 to 12 years. The parameters constituting the score were statistically tested on correlation with a reference set of success criteria, on mutual cross-correlations, and on the invariance to the implants' time-in-service. The PITS demonstrated to be highly representative of the success criteria, offering a fine scale from 0 to 10, and reversibility. Conclusion: The PITS withstood the tests. It responds to an existing need in the field, is widely accessible and inexpensive, and, thus, shows promise for use in general dental practice. Keywords: dental implants, implant stability, implant status monitoring, peri-implant tissue, success score