Comparison of Failure Rate between Temporary Anchorage Devices Placed in Infra-zygomatic Crest and Inter-radicular Bone during En-masse Retraction of Anterior Teeth of Maxilla

Abstract

Background: Temporary Anchorage Devices (TADs) play a crucial role in orthodontics by providing stable anchorage during en-masse retraction of maxillary anterior teeth. The choice of placement site can impact the stability and success of TADs. The purpose of the study is to compare the failure rates of TADs placed in the infra-zygomatic crest (IZC) and inter-radicular (IR) bone regions.
Objective: To assess and compare the failure rates of TADs between the infra-zygomatic crest and inter-radicular bone during en-masse retraction of maxillary anterior teeth.
Methods: A quasi-experimental study was conducted in the Department of Orthodontics, BMU, using 24 temporary anchorage devices (TADs) divided into two groups (12 TADs in each group) in 12 participants. Following a split-mouth design, in group A (IZC), TADs were placed in the infra-zygomatic crests and in group B (IR), TADs were placed in the molar-premolar inter-radicular sites. Each participants received 2 TAD, one in IZC and another in IR. The TADs were monitored at baseline and at monthly intervals over a three-month period to assess mobility or failure. A p-value of <0.05 was considered statistically significant.
Results: No significant difference in failure rates between the infra-zygomatic crest group and the inter-radicular group was found. The overall failure rate was 29.2%. Failure rates were 33.3% in the infra-zygomatic crest group and 25.0% in the inter-radicular group.

Conclusion: Within the limits of this study’s sample size and three-month observation period, both the infra-zygomatic crest and inter-radicular bone are viable and reliable sites for the insertion of TADs during en-masse retraction of the maxillary anterior teeth, as no statistically significant difference in failure rate was found between the two regions.

J. Contemp. Dent. Sci. 2026;14(2): 27-31