Primary stability in the posterior maxilla on an implant with a new macrogeometry: Torque vs. resonance frequency analysis – an in vivo study

Implants with decompression chambers can acquire secondary stability more effectively, despite their lower primary stability assessed with insertion torque. The low compression of the bone tissue around the implant tends to favor bone healing and regeneration in the region. The aim of this study was to evaluate the difference between the primary stability measurements of implants with decompression threads installed in the maxilla and whether the length of the implants can influence the stability results. Methods: implants installed in the maxilla were evaluated (Maestro implants, Implacil de Bortoli - São Paulo, SP, Brazil), allocated into two groups according to their length (Group 1, implants shorter than 10 mm and Group 2, implants longer than 10 mm). Primary stability was assessed by Resonance Frequency Analysis (RFA) by the Implant Stability Quotient (ISQ) and the insertion torque value of each implant. Results: 26 implants were inserted in 9 patients. When evaluated by insertion torque, group 1 had an average value of 23.99 Ncm, while group 2 had an average value of 32.91 Ncm, with a significant difference between the groups (p=0.012). In the evaluation by Resonance Frequency Analysis, an average value of 58.78 ISQ was observed in group 1 and 61.81 ISQ in group 2, with no statistically significant difference (p=0.06). Conclusion: the length of Maestro implants influences the mechanical stability measured in torque of implants installed in the posterior region of the maxilla.