ABSTRACT
The eight points cephalometric Treil model and the alveolodental parameters already allows an initial description of the maxillofacial framework and the teeth. Added six points allows taking into consideration an intermediate level: the maxillary and mandibular skeletal basis. So, the 14 points complete model allows a complete craniofacial anatomy description in three analysis levels: the framework or envelope, the osseous bases, the alveolodental arch. The correlation study between the 3D parameters at different levels defines the compensation notion. It allows understanding how skeletal disharmony may be distributed among the different levels. Only vertical direction compensations are analysed here.
Subject(s)
Cephalometry/methods , Facial Bones/pathology , Imaging, Three-Dimensional/methods , Malocclusion/diagnosis , Adult , Alveolar Process/pathology , Chin/pathology , Dental Arch/pathology , Female , Humans , Image Processing, Computer-Assisted/methods , Male , Malocclusion, Angle Class II/diagnosis , Malocclusion, Angle Class III/diagnosis , Mandible/pathology , Maxilla/pathology , Nasal Cavity/pathology , Orbit/pathology , Palate/pathology , Tomography, X-Ray Computed , Tooth/pathology , Vertical DimensionABSTRACT
The goal of this work is to study, using a sample of 95 persons, the parameters of the 14 points of the 3D Treil cephalometric analysis and to compare them to the facial volumes of these subjects. The 3D parameters are described on three levels and for all three dimensions of space; they are also defined statistically for each class of occlusion, and indications are given for sagittal two-dimensional variables. The correlations between all these variables and facial bones and air cavity volumes are also analyzed. The antero-posterior and vertical variables showed more statistically significant relationships with volumes than with transverse parameters. It appears that a Class III occlusion is primarily related to the vertical and antero-posterior position of the mandible and its morphology and not to its size, while Class II Division 1 types are associated with increased size of the maxillary sinuses. It also appears that facial hyper-divergence is related to a decrease in the size of the maxilla and the mandible.
