Biomechanical Parameters of Implants Placed with Osseodensification Versus Implants Placed with Under-drilling Osteotomy Techniques in Posterior Maxilla: A Comparative Clinical Study
Authors: Veljanovski Darko , Petrovski Mihajlo , Papakoca Kiro , Spirov Vanco , Susak Zoran , Baftijari Denis , Dervishoski Alil 
Published: June 2024

BACKGROUND: To facilitate better implant survival rates in areas with clinically low bone density, osteotomy techniques that provide higher implant stability and improve bone quality are often recommended. The most widely used are under-drilling (UD) and osseodensification (OD). In the UD technique, the diameter of the final osteotomy drill is narrower that the diameter of the placed implant, whereas in the OD technique, special drills that rotate counter-clockwise to condense and densify the bone are used.
AIM: The aim of this study was to evaluate the effect of two different implant osteotomy methods – UD versus osseodensification (OD) in terms of implant stability during the period of osseointegration in the posterior maxillary region.
MATERIAL AND METHODS: This prospective randomized clinical study included 22 patients who received a total of 37 implants in the posterior maxillary region. They were divided into two groups: In 11 patients, 18 implants were placed using the under-drilling method (UD), while the other 11 patients received 19 implants using the osseodensification method (OD). Within the OD group, 10 implants were placed in areas with the initial height that was insufficient to accommodate implants with a minimal length of 8 mm. In these areas, crestal sinus elevation without bone graft use was performed simultaneously with implant placement, according to the osseodensification protocol proposed by the manufacturer. All implants were placed in a dual-stage manner – completely covered with soft tissue and uncovered 4 months later, at the time of second-stage surgery. The implant stability was determined by measurement of implant stability quotient (ISQ) with instrument that utilizes the method of resonance frequency analysis (RFA) to discover implant stability. The ISQ represents a value on a scale between 0 and 100, with values above 65 indicating high implant stability. ISQ values were measured at two timepoints: At the time of implant placement and at the time of their uncovery. Statistical analysis was performed with Prism 9 statistical program for Mac. The data were analyzed using one-sample t-test, Wilcoxon, and paired two-way ANOVA test. The significance level was set at p ≤ 0.05.
RESULTS: The differences between the primary implant stability ISQ values in the UD and osseodensification (OD) groups were not statistically significant. The secondary implant stability was statistically significantly higher in the osseodensification group (p < 0.001) There were no statistically significant differences between secondary implant stability values in implants placed with and without crestal sinus floor lift within the osseodensification group.
CONCLUSION: Within the limitations of the study, the conclusion is that osseodensification method of implant osteotomy (OD) results in higher secondary implant stability values that the under-drilling method (UD), which has clinical relevance regarding long-term implant survival. It should be a preferred method of choice for osteotomy in areas with clinically low density of bone due to its predictability and effectiveness.