Assessment of bone thickness at infrazygomatic crest: A CBCT study

Objective: To evaluate the bone thickness at infrazygomatic crest as a site for orthodontic mini-implant insertion.

Materials and methods: Fifty CBCT images were collected from a CBCT centre. Slice data were analysed and measurements were done at three sites. The measurements were made at three different angles. These measurements were repeated both on the right and left sides of IZC 6 AND IZC 7. The data were analysed using two sample t test and Mann Whitney U test.

Results: The maximum bone thickness was evident at IZC 7 region (7.88mm) and in IZC 6 the bone thickness was (7.0 mm). The bone thickness measured at an angulation of 150 from cemento enamel junction showed increased bone thickness available at infrazygomatic region irrespective of roots. As the angulation increased bone thickness decreased. There was no difference between right and left side.

Conclusion: The cortical bone thickness between right and left side of IZC 6 and IZC 7 was similar and statistically insignificant. The thickness at mesiobuccal root of IZC 6 was less when compared to IZC 7. Similarly, at the distobuccal root. Hence the ideal site would be IZC 7or our population without compromising the primary stability. The result of this study indicated that the average cortical bone thickness at IZC 7 was greater than IZC 6. The mean thickness at IZC 7 (7.88 mm) but at IZC 6 (7 mm).