The application of the diagnostic 3-D imaging procedures in maxillofacial orthopedics

Abstract

CBCT/ CT Cone beam/ computed tomography CFAs Craniofacial anomalies OMSs Oral and maxillofacial surgeons AAOMS Association of oral and maxillofacial surgeons MCA Multiple congenital abnormalities CL/P Cleft lip and palate CO Central occlusion CR Central relation RME Rapid maxillary expansion 2D Two-dimensional 3D Three-dimensional 4D Four-dimensional MRI Magnetic resonance imaging TMJ Temporomandibular joint CMM Coordinate measurement machines LED Light emitting diode STL Stereolithography ICC Interclass correlation coefficient ADRL Average distances between the reciprocal landmarks BSSRO Bilateral sagittal split ramus osteotomy MSS Mandibular setback surgery Skeletal and dental consideration in the transverse dimensionMaxillary transverse deficiency may be one of the most pervasive skeletal problems in the craniofacial region (7). The transverse dimension is often interrelated with the sagittal and vertical dimensions. However, the transverse dimension relates primarily to the posterior occlusion, and any discrepancy is usually manifest as a unilateral or bilateral crossbite of the buccal occlusion. Conservative correction of the maxillary transverse deficiency 1.3.2.1 Unilateral posterior crossbite in cleft lip and palateMaxillary skeletal asymmetry in unilateral complete clefts of the lip and palate may also be reflected in a unilateral posterior crossbite, which may be expanded with a quad helix type of appliance or rapid maxillary expansion (RME) in the mixed dentition. The cleft maxilla does not have a midpalatal suture, instead, there is a midpalatal cleft covered with repaired and scarred palatal tissues limiting the rate and amount of expansion. The force provided by these appliances allows the soft tissue of the palate to stretch and adapt to the increasing maxillary width. This type premolars. This may be accomplished with a hyrax type appliance screw (Figure 3, A). The patient Surgical correction of the craniofacial deformities:According to the American Association of Oral and Maxillofacial Surgeons (AAOMS), orthognathic surgery is the surgical correction of abnormalities of the mandible, maxilla, or both.The underlying abnormality may be present at birth or may become evident as the patient grows IndicationsGiven the relationship between facial skeletal deformities and masticatory dysfunction as well as the limitations of non-surgical therapies to correct these discrepancies. The measurement of these discrepancies must consider dental compensations relating to the malocclusion and the underlying skeletal deformity. Orthognathic surgery should be considered medically appropriate in the following circumstances (11):A. Anteroposterior discrepancies: established norm=2mm 1. Maxillary/mandibular incisor relationship  Horizontal overjet of +5mm or more  Horizontal overjet of zero to a negative value 2. Maxillary/mandibular anteroposterior molar relationship discrepancy of 4mm or more (norm 0 to 1mm) 3. These values represent two or more standard deviation from published norms 1.6.2.2 Intraoral Scanning W...