Int J Oral Implantol (Berl) 13 (2020), No. 3 2. Sep. 2020
Int J Oral Implantol (Berl) 13 (2020), No. 3 (02.09.2020)
Page 241-252, PubMed:32879929
Bone modifications around porous trabecular implants inserted with or without primary stability 2 months after tooth extraction: A 3-year controlled trial
Bianconi, Stefano / Wang, Hom-Lay / Testori, Tiziano / Fontanella, Fabrizio / Del Fabbro, Massimo
Purpose: Implant primary stability has long been considered a prerequisite for successful osseointegration. However, achieving stability may be difficult when placing implants in wide postextractive bone defects. The purpose of this study was to conduct a clinical and radiographic investigation of bone modifications at porous-structured implants inserted with or without primary stability.
Materials and methods: Fifty porous-structured implants were inserted in the posterior sockets of 50 consecutive patients 2 months after tooth extraction, combined with allogeneic bone and a resorbable membrane. The implants were divided into two groups according to insertion torque: spinner (spinning at 35 Ncm, n = 23) and stable (stable at 35 Ncm, n = 27). Implant stability was assessed by resonance frequency analysis from baseline to 6-month function. Follow-up took place 3 years after implant placement.
Results: At baseline, the implant stability quotient was undetectable in the spinner group and averaged 75.07 ± 5.84 in the stable group. At uncovering, the implant stability quotient increased to 71.33 ± 4.42 and 77.97 ± 3.30 in the spinner and stable group, respectively (P < 0.001). After 6 months of loading, no between-group difference in implant stability quotient was found (P = 0.13). Marginal bone level changes were similar between groups at all follow-ups, averaging −0.41 ± 0.77 mm and −0.15 ± 0.53 mm at 36-month follow-up in the spinner and stable group, respectively (P = 0.35). No implant failed throughout the observation period. Neither biological nor mechanical complications occurred.
Conclusion: Implants with a moderately rough surface and a porous-structured body may osseointegrate even without primary stability.
Conflict-of-interest statement: Dr Bianconi, Prof Testori, Dr Fontanella and Prof Del Fabbro declare no conflicts of interest. Prof Wang received an honorarium to lecture at the Zimmer Biomet 3i NYU Symposium 2018.
Keywords: alveolar bone resorption, bone regeneration, dental implants, implant primary stability, osseoincorporation, osseointegration, osseous defects