Page 29 - Peri-implant health: the effect of implant design and surgical procedure on bone and soft tissue stability

HOW DO PERI-IMPLANT BIOLOGIC PARAMETERS CORRESPOND WITH IMPLANT SURVIVAL AND PERI-IMPLANTITIS? A CRITICAL REVIEW
after implant placement but should relate to baseline recordings once tissue homeostasis has been established, in essence 3 months after completion of the treatment.34 Today, there is a general consensus that a baseline radiograph is required for the assessment of bone changes over time.31 It is unfortunate that, this baseline radiograph is not always available when clinicians assess the peri‐implant tissue condition. For these conditions, a pragmatic clinical approach for peri‐implantitis diagnosis was suggested by the 8th European Workshop for Periodontology.35 The consensus report suggested a 2 mm additional loss beyond the “expected” bone level as a threshold in situations where baseline radiographic bone level assessment is lacking.
Bone loss
Although the threshold for bone loss as a diagnostic criterion for disease is not exactly specified in the previous EFP or EAO consensus meetings, there is agreement on the fact that stable crestal bone levels are most important for implant success because it is paramount for long‐term survival, esthetics, as well as peri‐implant health. Klinge and colleagues advised that critical bone loss ≥ 2 mm from the time of placement of the prosthetic device, in combination with bleeding on probing, should be interpreted as a “red flag” for the clinician to critically evaluate whether any intervention is indicated in the individual case and whether follow‐up and reassessment are required to confirm ongoing bone loss.34
De Bruyn and colleagues reviewed radiographic assessment of modern implants and suggested that this mean bone loss assessment in patients with multiple implants yields very limited information on the condition of individual implants.36 However, it may be valid to benchmark implant systems. Given the fact that a majority of implants have very stable crestal bone levels over time and in a majority of cases sometimes no bone loss at all, the statistical interpretation of mean values often hides the condition of individual implants. It may be the reason why in the early studies, with mostly multiple implant cases for complete jaw rehabilitations, disease may have been overlooked. This is obvious from a radiographic follow‐up study of 640 patients with 3,462 turned implants.37 The mean bone loss after 5 years was 0.8 mm, and insignificant changes were reported in the years thereafter. However, the prevalence of implants with bone level located 3 mm apical to the implant-abutment junction was 2.8% at the time
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