Cone-beam computed tomography transverse analysis. Part I: Normative data

Objective: To identify differences in occlusal curvatures and maxillary arch dimensions between subjects with signs and symptoms of temporomandibular disorders (TMDs) and asymptomatic subjects. Materials and Methods: One hundred subjects (78 female and 22 male) who consented to participate in this research were examined for signs and symptoms of TMDs according to the guidelines of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC-TMD). In addition, occlusal measurements were performed for all subjects on plaster models. All statistical analyses were performed with SPSS (version 19). Results: Significant associations were revealed between the depth of the curve of Spee (COS) and temporomandibular joint (TMJ) sounds. Furthermore, maxillary arch width was negatively correlated to the steepness of the curve of Wilson. No differences were found between subjects with and without a history of orthodontic treatment. Conclusions: Subjects with TMJ sounds tend to have a flatter COS compared to subjects without TMJ sounds. (Angle Orthod. 2014;84:96-101.)

Section: Discussioncontrasting

confidence: 45%

The role of occlusal curvatures and maxillary arch dimensions in patients with signs and symptoms of temporomandibular disorders

Kanavakis

Mehta

2013

“…It has been reported 22 that the rate of incorrect transverse diagnosis from PA films is significantly larger than that associated with CBCT (18.0% vs 8.7%). Miner et al 12 proposed a CBCT-based transverse analysis to classify transverse jaw problems and to differentiate related dental compensations. Adopting their approach for transverse analysis, the results of this study indicate that regardless of whether or how the upper and lower teeth compensate for transverse discrepancy, deficient maxillary width is significantly associated with narrower lower incisor bony support.…”

Section: Discussionmentioning

confidence: 99%

“…(1) Vertical facial pattern was determined by posterior anterior facial height ratio (SGo/Na-Me, PA ratio) measured on a cephalogram 12 Briefly, all subjects were dichotomized into the permanent first molar crossbite group and the non-crossbite group. Then the non-crossbite group was further subdivided into the following three groups: normal group, superior convergent group, and inferior group; subdivision was according to the buccal-lingual inclination of the permanent first molar on the coronal slice (Figures 2 and 3).…”

Section: Measurementsmentioning

confidence: 99%

Dentofacial traits in association with lower incisor alveolar cancellous bone thickness: A multiple regression analysis

Liu

Wang

et al. 2016

Objective: To identify dentofacial anatomic traits associated with lower incisor cancellous bone thickness (LICBT) and then to assess their separate contributions and their combined contributions to the variation in LICBT. Materials and Methods: A consecutive sample of cone beam computed tomography (CBCT) data taken in a university hospital within the same setting was retrospectively reviewed. Within the sample, CBCT data of 252 eligible subjects were reconstructed and measured for LICBT, facial traits, and mandibular symphyseal traits. A backward multiple linear regression was employed to explore the association between LICBT and seven representative dentofacial traits. Results: Four dentofacial traits (vertical facial pattern, transverse jaw relationship, lower incisor cervical diameter, and mandibular symphyseal width) were identified as significantly associated with LICBT. The combination of these four factors could predict 64.3% of variations in LICBT (adjusted R 2 ¼ 0.643). Further comparison of LICBT among different transverse jaw relationships suggested that the LICBT of the normal (5.94 6 1.58 mm) group and the inferior convergent group (5.38 6 1.32 mm) were significantly larger than that of the crossbite group (4

“…Maxillary molar compensation was apparent on the deviated side only, whereas mandibular molars showed significant axes changes on the deviated and nondeviated side. In order to assess jaw width and first molar inclination, Miner et al 18 obtained normative data of CBCT analysis based on their control group. They reported that the maxillary molar axial angle was approximately 98u, and the mandibular axial angle was 104u.…”

Section: Discussionmentioning

confidence: 99%

Three-dimensional analysis of molar compensation in patients with facial asymmetry and mandibular prognathism

Tyan

Park

Munkhshur

et al. 2015

Objective: To evaluate the characteristic transverse dental compensations in patients with facial asymmetry and mandibular prognathism and to compare features of dental compensations between two types of mandibular asymmetry using 3-dimensional (3D) cone-beam computed tomography (CBCT). Materials and Methods: Seventy-eight adult patients with skeletal Class I (control group; n 5 33; 19 men and 14 women) or skeletal Class III with facial asymmetry (experimental group; n 5 45; 23 men and 22 women) were included. The experimental group was subdivided into two groups according to the type of mandibular asymmetry: translation type (T-type; n 5 20) and roll type (R-type; n 5 19). CBCT images were acquired before orthodontic treatment and 3D analyses were performed. Results: The transverse dental distance was significantly different between the two groups only at the palatal root apex of the maxillary first molar (P , .05). In the experimental group, the first molar axes were compensated significantly on both arches except the maxillary nondeviated side. The vertical molar heights were different between the two groups only on the maxillary arch (P , .001). The R-type showed greater mandibular ramal length difference and menton deviation than the T-type (P , .001). In the R-type, transverse compensation of the maxillary first molars was more obvious than with the T-type, which resulted in canting in the maxillary occlusal plane. Conclusions: Mandibular asymmetry with prognathism showed a characteristic transverse dental compensation pattern. The mandibular asymmetry type influenced the amount and direction of molar compensation on the maxillary arch. (Angle Orthod. 2016;86:421-430.)