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Background The aim of this study was to evaluate the midpalatal suture maturation stages in adolescents and young adults using cone-beam computed tomography (CBCT). Methods The sample comprised 200 CBCT scans of individuals aged 10 to 25 years old (95 males and 105 females) divided into three groups, adolescents (n = 48), post-adolescents (n = 52), and young adults (n = 100). The Planmeca ProMax 3D software was used for the midpalatal suture maturation stage evaluation according to Angieleri’s method, using cross-sectional axial slice. Two previously calibrated examiners analyzed the images and classified according to five different maturation stages. A, B, and C stages were considered with open midpalatal suture, and D and E were considered without open midpalatal suture. Association tests were performed using chi-square test also, and a binary logistic regression was evaluated (P < 0.05). Results The possibility to find open midpalatal suture in individuals of 10 to 15 years old was 70.8%, in subject aged 16 to 20 and 21 to 25 years old was 21.2% and 17%, respectively. Furthermore, this possibility in individuals older than 16 years was greater in males than in females. Conclusions The possibility to find open midpalatal suture in post-adolescents and young adults is greater than the orthodontists considered years ago. Furthermore, men are more likely to find midpalatal suture opening. These implications might be considered by the orthodontists when maxillary expansion is required. Besides, the ossification of the middle palatal suture is very variable, and therefore, the use of CBCT might be recommended to clarify this possibility.

BackgroundThe aim of this investigation was to compare skeletal and dentoalveolar measurements of subject with unilateral palatally impacted canine versus the unaffected contralateral side on cone beam computed tomography (CBCT).MethodsA cross-sectional study (split mouth design) that included 28 CBCTs (i.e., 56 sides) with unilaterally impacted maxillary canines was performed. After conducting a pilot test to gauge the researcher, heights and widths of skeletal and dentoalveolar variables obtained in the maxilla were measured using coronal and axial views. The angulations of incisors were also measured, and the side with impaction and the unaffected side were compared. Paired sample t test and Wilcoxon signed-rank test were used.ResultsSignificant statistical differences (2 mm, p < 0.001) were found between the impacted and non-impacted side measurements from the mid-palatine raphe to the first premolar (proximal alveolar bone crest between the canine (deciduous or permanent) and first premolar); the distance were significantly lower (12.72 ± 2.25 mm) than in the side without impaction (14.67 ± 2.00 mm). Also, the central and lateral incisor angulations showed significant reductions; presenting disto-angulated incisors on the impacted canine side (86.14 ± 7.70° and 74.75 ± 12.67°, respectively) and mesial-angulated incisors on the non-impacted side (91.63 ± 6.79° and 81.21 ± 8.56° respectively). The other skeletal and dentoalveolar measurements showed no significant differences.ConclusionsThe width from the median raphe to the first premolar is lower in the side of maxillary palatal impacted canines than in the side without impaction. Lateral angulations of incisors were disto-angulated on the side of impacted canines. Both conditions have clinical implications in the orthodontic treatment.

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BackgroundThe present study was performed to compare follicle dimensions of impacted mandibular third molar (IMTM) with different impaction angulations using cone beam computed tomography (CBCT).Material and MethodsForty-nine individuals with IMTM (24 male, 25 female) were selected. Their age range was 25-55 years. The sample was divided into three IMTM groups either vertical (n=16), mesioangular (n=18) or horizontal (n=15) position based on Winter’s classification (the angle between the longitudinal axis of the second and third molars). Follicular spaces (FS) from available CBCT imaging were measured from the midpoint of the teeth’s crown in several dimensions (mesial, distal, occlusal, apical, vestibular and lingual) in axial, sagittal and coronal planes. An ANOVA, T-student, Kruskal–Wallis and Mann-Whitney U tests were used.ResultsA comparison of the mesial FS for all groups revealed significant differences (p<0.001). Significant difference was also found for vestibular FS between the vertical and mesioangular IMTM groups (p=0.04). Buccolingual FS for all groups revealed no significant differences (p=0.074), whereas significant difference was found for the vertical and horizontal IMTM groups (p=0.02). No significant statistical differences were found for occlusal (p=0.54), apical (p=0.06), and lingual (p=0.64) FS.ConclusionsIn this sample IMTM follicles have different dimensions according to their degree of angulation. Mesioagulated and horizontally positioned IMTMs seems to consistently have some increased FS dimensions (mesial and vestibular aspects). Key words:Dental follicle, impacted tooth, third molar, cone-beam computed tomography.

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OBJECTIVE: The objective of this study was to evaluate the Björk and Jabarak cephalometric analysis generated from cone-beam computed tomography (CBCT) synthesized lateral cephalograms in adults with different sagittal skeletal patterns. METHODS: The sample consisted of 46 CBCT synthesized cephalograms obtained from patients between 16 and 40 years old. A Björk and Jarabak cephalometric analysis among different sagittal skeletal classes was performed. Analysis of variance (ANOVA), multiple range test of Tukey, Kruskal-Wallis test, and independent t-test were used as appropriate. RESULTS: In comparison to the standard values: Skeletal Class III had increased gonial and superior gonial angles (P < 0.001). This trend was also evident when sex was considered. For Class I males, the sella angle was decreased (P = 0.041), articular angle increased (P = 0.027) and gonial angle decreased (P = 0.002); whereas for Class III males, the gonial angle was increased (P = 0.012). For Class I females, the articular angle was increased (P = 0.029) and the gonial angle decreased (P = 0.004). Björk's sum and Björk and Jabarak polygon sum showed no significant differences. The facial biotype presented in the three sagittal classes was mainly hypodivergent and neutral. CONCLUSIONS: In this sample, skeletal Class III malocclusion was strongly differentiated from the other sagittal classes, specifically in the mandible, as calculated through Björk and Jarabak analysis.

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