Outcome of Three vs. Four Early-loaded Transgingival Mandibular Implants

Outcome of Three vs. Four Early-loaded Transgingival Mandibular Implants
L. MOLLY1, D. VAN STEENBERGHE1, M. QUIRYNEN1, B. VANDEKERCKHOVE1, F. ARDENOIS2, R. JACOBS1, and I. NAERT2, 1 Cathol. Univ. Leuven, Dept. Periodontol, Belgium, 2 Cathol. Univ. Leuven, Dept. Prosth. Dent, Belgium
2003
IADR
Objectives: Early loading of oral implants has been performed since the eighties with various success rates. Recently a novel approach implying the use of a cad-cam manufactured titanium bridge (Procera Implant Bridge¨?, Nobel Biocare, Sweden), which can be installed within two weeks, encouraged early loading of implants at least in the symphysis with its favorable bony characteristics.
Methods: At the department of periodontology two series of 10 edentulous patients each, received either 3 (group A) or 4 (group B) conical transgingival implants in the symphyseal area. Within ten to twenty days the fixed full prosthesis was tightened on top of the implants at the department of prosthetic dentistry. The patients were encouraged to use until that time soft food, and afterwards to exert chewing forces with great care for at least 2 months.
Results: The number of failed implants in groups A and B at 1 year were respectively 0 and 8 (clustered in 2 patients). Losses were due to early (within 3 months) non-integration and occurred in two heavily smoking patients. Age and extraction at surgery did not affect the outcome. Average marginal bone losses for groups A and B were respectively 0.65 mm (SD: 1.04) and 0.29 mm (SD: 1.04), reaching statistical significance in group A only (Wilcoxon matched pairs test).
Conclusion: This study shows that early loading of 3 or 4 implants rigidly connected in the symphyseal area is possible. The lower limit of this number remains unknown, although with 3 implants more marginal bone loss was observed.