Early loading (2 or 6 weeks) of sandblasted and acid-etched (SLA) ITI® implants in the posterior mandible. A 1-year randomized controlled clinical trial

Abstract

The aim of this 1-year prospective controlled clinical trial was to evaluate the effect of early loading of ITI® solid screw titanium implants with a sandblasted and acid-etched (SLA) surface on clinical and radiographic parameters. Material and methods: Twenty-seven consecutively admitted patients presenting bilateral edentulous posterior mandibular areas and in need of prosthetic reconstruction were recruited. Sixty-seven ITI® standard solid screw implants with an SLA surface, a diameter of 4.1 mm and a length of 8, 10 or 12mm were installed bilaterally in molar and premolar areas according to a one-stage surgical protocol. One week (test) and 5 weeks (control) after implant placement, solid ITI® prosthetic abutments were connected using a torque of 35 N cm. No provisional restoration was fabricated. Two weeks (test) and 6 weeks (control) after implant placement, porcelain-fused-to-metal single-tooth crowns were cemented. Clinical measurements were obtained at day O and 2, 6, 12, 24 and 52 weeks thereafter. Periapical radiographs were taken immediately after implant placement, after 6 weeks and at the 1-year examination. Results: After 1 year, implant survival was 100%. Two test and one control implants rotated at the time of abutment connection and were left unloaded for 12 additional weeks. At the 1-year examination, no statistically significant differences were found between the test and control sites with respect to pocket probing depths (2.6 mm ± 0.5 vs. 2.7 mm ± 0.5), mean clinical attachment levels (3.1 mm ± 0.4 vs. 3.2 mm ± 0.5), mean percentages of sites bleeding on probing (9.7% vs. 8.3%), mean widths of keratinized mucosa (1.8 mm ± 0.4 vs. 1.9 mm ± 0.5), mean PerioTest® values (- 1.4 PTV ± 0.9 vs. - 1.6 PTV ± 0.8) or mean crestal bone loss measurements (0.57 mm ± 0.49 vs. 0.72 mm ± 0.50). Conclusion: Based on these results, loading of titanium implants with an SLA surface as early as 2 weeks did not appear to jeopardize the osseointegration healing process in the posterior mandible. Furthermore, implants rotating at 35 N cm, if left unloaded for additional 12 weeks, did not negatively affect clinical and radiographic outcomes.