Evaluation of biological width around implants inserted in native alveolar crest bone

Aim Biological width represents the distance necessary for a healthy existence of bone and soft tissue around teeth and/or implants. The mean value is about 3 mm and if it is compromised there is a greater probability of resorption of interproximal alveolar crest. Materials and methods A retrospective study was performed on a series of 234 Spiral family Implants (SFIs) in order to detect the minimal biological width between implants or between tooth and fixture that does not determine a crestal bone resorption. The series was split in two groups: distances ‰¤1.8 mm and ‰¥ 1.9 mm. Lost implants and crestal bone resorption around implant neck were considered as survival and success outcome and several clinical variables were matched against them by using Kaplan-Meyer and chi-square tests. Results No statistical significant difference was demonstrated between the two groups (i.e. ‰¤1.8 mm and ‰¥1.9 mm), but a clear trend over time was detected with a greater crestal bone resorption for distances ‰¤1.8 mm. Conclusion The data confirm the importance of a correct IID and add new information as regard fixtures with reverse conical neck which permits the use of a reduced IID.