OBJECTIVE
To conduct a comparative analysis of the sizes and positions of maxillofacial structures in patients with distal occlusion (gnathic and dentoalveolar forms) using a new 3D analysis.
MATERIAL AND METHODS
The object of the study were 132 patients with the gnathic form of distal occlusion of both sexes aged 18 to 45 years, including 79 women and 53 men. All patients underwent cone-beam computed tomography of the skull using KavoExam equipment with subsequent automated 3D cephalometric calculation in ViSurgery 3Dstudio software. We assessed 3D parameters on the right and left sides, as well as their 2D projection onto the midsagittal plane constructed using landmarks — cephalometric points S, N, A. Linear and angular parameters of the position and relative position of the jaws were determined using the values of Witts, SNA, SNB, ANB, B-A-Pg, S-N-Pg, ML-R/NSL, ML-L/NSL, NL-R/ML-R, NL-L/ML-L, ML/OcP, GoR — PNS, GoL-PNS and their projection onto the midsagittal plane. The angular parameters determining the direction of facial skull growth on the right and left corresponded to N-S-ArR, N-S-ArL, ArR-GoR-Me, ArL-GoL-Me, CoR-GoR-Me, CoL-GoL-Me. The angles and sizes of the position of the upper (∠SNA, PNS-A’), lower (∠SNB, Go-Pg) jaw relative to the anterior base of the skull, and the intermaxillary angle (∠ANB) were determined.
RESULTS
In both males and females, the gnathic form of distal occlusion was caused by lower retro-, micrognathia with prevalence of the horizontal type of growth of the facial part of the skull. For males and females with the dentoalveolar form of distal occlusion, the vertical type of growth of the facial part of the skull was characteristic; at the same time, lower micrognathia was noted, as in individuals with the gnathic form of distal occlusion.
CONCLUSION
The proposed cephalometric analysis in the ViSurgery software allows for an automated detailed study of the cranial-maxillary relationships in three-dimensional space and a complete picture of the severity and determinacy of the existing anomaly.
