A 10 year prospective clinical research study by Karoussis et al (2004) evaluated the periodontal and peri-implant conditions in a cohort of 89 edentulous patients (mean age 58.9 years) in order to assess the environmental, physiological and radiographic changes in the dental implants over a long period of time post-implantation. The rationale for this clinical research study involves the need to establish reliable data relevant to the use of dental implants in patients who have had tooth extractions. These types of data are difficult to obtain since they require long term assessments of patients who have received dental implants. These longitudinal single subject studies also require recruitment of large patient cohorts and need to address physiological and environmental factors that affect long-term success rates for dental implant procedures. The study participants were evaluated at one year and again at 10 years post implantation to evaluate the changes periodontal peri-implant conditions in individual patients. This study also incorporated an evaluation of risk factors associated with sub-optimal patient outcome post-implantation.
Patients recruited in this study had previously been treated for periodontal disease and also had received prosthetic structures such as fixed partial dentures and crowns. ITI dental implant system was used in all patients enrolled in this study. Within this cohort a total of 179 implants were assessed; the same number of control natural teeth were included as a basis of comparison. In addition, all remaining teeth were examined in these patients. Patient behavioral risk factors, particularly cigarette smoking, were also evaluated in this study.
The data parameters assessed in this study included plaque index (PI) for teeth and modified plaque index (MPI) for implants, gingival index (GI) for