ISQ measurement of dental implants placed simultaneously with lateral sinus floor elevation

Background: Good primary stability of dental implants placed simultaneously with lateral sinus floor elevation (LSFE) provides successful implant osseointegration. Residual height and quality of bone are the main factors which determine primary stability. Sometimes these conditions can be so aggravated that they do not offer the possibility to achieve primary stability. By measuring implant stability quotient (ISQ) we can quantify and predict the successful outcome. Aim: is to find out the influence of residual alveolar ridge height on primary stability and success rate of osseointegration by measuring ISQ of dental implants placed simultaneously with LSFE.Material and methods: We inserted 15 implants in 8 patients. Implants were placed in different types of alveolar ridges simultaneously with LSFE augmented with deproteinised bovine bone mineral and divided in two groups. Group 1 (G1) was composed of implants placed in ridges with residual height more than 3 mm, n=7. In group 2 (G2) implants were placed in ridges with less than 3 mm of residual height, n=8. By measuring ISQ with Osstell we assessed primary stability immediately after insertion of implant and success rate of osseointegration 4 months later. Measurements were compared and statistically analyzed.Results: All implants osseointegrated successfully after 4 months of osseointegration. Statistically significant difference was found between ISQ values of implants in G1 and G2 immediately after implant placement. After 4 months of osseointegration there was no statistically significant difference between ISQ values in both groups. Conclusion: It seems that residual alveolar ridge height plays an important role in achieving high primary stability of implants placed simultaneously with LSFE and does not influence on the success rate of osseointegration after 4 months.