Comparative analysis of zygomaticus implants placed with the intra-sinus technique and the extended sinus lift technique

Abstract

Introduction Posterior maxillary atrophy in particular presents a challenge for implant-supported dental rehabilitation. The discovery of the zygomaticus implant by Branemark and its modifications has brought a much-needed window of hope to most patients with atrophic maxilla. Techniques ranging from intrasinus to extended sinus lift technique are used to place zygomaticus implants. There is paucity of studies that have reported on the outcome of zygomaticus implants using these two techniques.Aim: The aim of the present study was to compare treatment outcomes of zygomaticus implants placed via the extended sinus lift technique and the intra-sinus technique. Materials and Methods: This was a retrospective record-based study of patients treated with zygomaticus implants after removal of tumors, trauma to the facial skeleton or edentulous maxilla due to premature loss of dentition. Records of patients restored with zygomaticus implants using the above two techniques were analyzed. Data such as age, gender, and type of treatment were recorded. The complications and success rates of the two techniques were analyzed using the assessment criteria designed by Aparicio (2010) (Annexure B). Data were analyzed and results presented as frequencies and percentages

RESULTS: Over the period of the study, 60 (87.0%) of the study participants received zygomaticus implants via the extended sinus lift technique as compared to the intra-sinus cases where only 9 (13.0%) cases were treated. The success rate of the intra-sinus technique over the 96 months was found to be 77.8% while the success rate for the extended sinus lift technique was 100 %. Both univariate and multivariate analyses confirmed the association between sinus complication and type of procedure: more sinus complications were noticed in the intra-sinus. group than in the extended sinus lift group (66.7% vs. 1.7%), which was statistically significant (p value <0.001). The intra-sinus technique was also associated with a Lund –Mackay score of 14 (58%), compared to a score of zero with the extended sinus lift technique. CONCLUSION: The extended sinus elevation technique has been shown in this study to have a superior advantage over the intra-sinus technique in reducing the risk of maxillary sinusitis, or other maxillary sinus complications. We however advise that the results of this study be interpreted with caution as there was a disproportionate distribution of patients between the two groups or two techniques. We also recommend that more large scale and balanced studies be undertaken to validate the findings of our study.