Zygoma quad compared with 2 zygomatic implants – A systematic review and meta-analysis

Background

The oral rehabilitation of the atrophic maxilla is a great challenge for the oral and maxillofacial surgeon. There are different treatment options that can lead to an optimal functional and esthetic rehabilitation, such as sinus augmentation, onlay and inlay grafts, split crest technique, pterygoid implants, and osteogenic distraction. The development of the zygomatic implants in the 90s represented a new treatment option for the severely atrophic maxilla. There are several publications that support the safety of this technique to return the function and aesthetics of the oral cavity. The main advantages of this technique are that it reduces the treatment time only requiring 1 surgical approach, and it avoids further surgeries in donor sites needed for bone harvesting. The number of zygomatic implants may vary from 1 to 4. The most common treatment option for a complete rehabilitation of the maxilla is a combination of 2 zygomatic implants with regular implants and or pterygoid implants or the use of 4 zygomatic implants.

Aim/Hypothesis

The aim of this study was to systematically review and compare the survival rates of oral rehabilitations performed with 2 zygomatic implants combined with regular implants versus 4 zygomatic implants.

Material and Methods

An electronic search was performed in several databases for articles published in English between 2007 and 2015. Articles reporting human studies were included in this systematic review.

Results

The search yielded to a total of 417 studies, of which 6 were included in this study. Zygomatic implants survival rate weighted mean was 98.0% with a 95% confidence interval of 96.7% to 99.8%. For the control group (two zygomatic implants with two regular implants) and the test group (four zygomatic implants), the implant survival rate was 98.6% and 97.4%, respectively, with a 95% confidence interval. No statistically significant differences in terms of survival rate were obtained between both groups (P-value = 0.286).

Conclusion and Clinical Implications

The data analysis showed favorable results for treatment with four zygomatic implants. The results showed no statistical differences in using 1 or another treatment, in terms of survival and failure rates. The reduction on treatment time and morbidity related to regenerative approaches may be its main advantage. In conclusion, the zygoma quad seems to be the treatment of choice for the rehabilitation of the severely atrophic maxilla.