Pearson correlation test revealed a significant negative correlation between the distance and the patient's age. Conclusions Our study provides valuable information for planning orthodontic tooth movement through the maxillary sinus, which may help to predict the occurrence and severity of root resorption.Introduction Rapid palatal expansion is an effective intervention for correcting transverse maxillary deficiency in growing patients. However, relapse after treatment is often observed, and the mechanisms of tissue remodeling during expansion and relapse remain unclear. This study aimed to gain insight into such a mechanism. Methods A total of 24 5-week-old male Wistar rats were randomly divided into either the expansion or sham device (control) group. Each rat underwent 7 days of expansion and 7 days of relapse. The width of the dental arch, palatal bone, and suture, as well as the angle of the teeth, were measured. https://www.selleckchem.com/ Tissue remodeling in the midpalatal suture was examined using microcomputed tomography and histologic and immunohistochemical analyses. Results The mechanical expansion force caused an increase in arch width, which relapsed after the removal of force. Bilateral tilting of the teeth and midpalatal suture expansion contributed to the widening of the maxillary arch, and only the relapse of the palatal bone width was observed. Histochemical staining showed that suture tissue remodeling was activated by mechanical force in the expansion group and reverted to the level of the control group after relapse. Immunohistochemistry staining revealed that the expression of cathepsin K, osteocalcin, and collagen type I was higher in the expansion group than that in the control group on day 7; however, the difference dissipated by day 14. Conclusions The expansion force stimulated osteogenic activity in the midpalatal suture area. After removal of the expansion force, tissue remodeling went back to the normal level.Introduction Patients seeking orthodontic treatment often have esthetic concerns (ie, they want a better smile). Patients with increased vertical facial dimensions have different smile traits than other patients. This study aimed to compare the smile characteristics of subjects with different vertical facial dimensions and to use stereophotogrammetry to evaluate the changes in facial animation upon smiling. Methods One hundred twenty adolescents and young adults (aged 15-25 years) who were referred for orthodontic treatment were divided into 2 groups according to their vertical facial height increased (n = 30) and normal (n = 30). Three-dimensional stereophotogrammetric images were obtained from the patients during rest and smile. The images were superimposed, and the displacements of specific landmarks were recorded. Linear, angular, and proportional measurements were recorded on the smile and rest images. Results When smiling, horizontal movement of commissures was less (right, P = 0.038; left, P = 0.009), upper lip elevation was higher (P = 0.014), and the upper lip was shorter (P = 0.014) in the vertical group than in the normal group. In the vertical group, the interlabial gap was increased both at rest and when smiling (P less then 0.001). Statistically significant differences were found in smile index (P = 0.001), nasolabial fold displacement (P = 0.018), and lip angles (both P = 0.001) between groups. Conclusions Group and sex differences were observed when smiling. Careful consideration of these differences will help clinicians in proper diagnosis and treatment planning.Introduction Many studies have investigated the impact of orthodontic treatment need (OTN) on children's oral health-related quality of life (OHRQOL). However, few studies have explored the impact of deviant occlusal traits on OHRQOL regarding the severity of OTN. This cross-sectional study aims to address this gap in the literature. Methods This study was conducted within the Generation R Study, a population-based prospective cohort study. We assessed OTN with the Index of Orthodontic Treatment Need and OHRQOL with a parental short-form of the Child Oral Health Impact Profile in 3048 children at a median age of 9.74 years (9.5-10.0). We also further assessed individual malocclusion traits in a subsample of 2714 children. We investigated the association between OTN, malocclusion traits, and OHRQOL using multiple regression analysis with weighted least squares. Results Children with definite (adjusted effect estimate = -0.81; 95% confidence interval -1.12 to -0.50) or borderline (adjusted effect estimate = -0.34; 95% confidence interval -0.61 to -0.08) OTN experienced significant decreases in their OHRQOL than those with no need. An impacted tooth, increased overjet, or crowding had significant negative impacts on children's OHRQOL. Children with an overjet experienced negative impacts on OHRQOL even when orthodontic treatment was not necessary. Conclusions Progressively greater OTN has increasingly negative impacts on parent's perception of children's OHRQOL. In particular, children presenting with large overjets and impacted teeth have lower OHRQOL. These perspectives add to better patient-clinician communication and understanding of patient expectations around OTN, which may potentially lead to improvements in quality of care from the patient perspective.Introduction Little is known about the influence of biological characteristics on the occurrence of malocclusion. This study aimed to investigate the association between preterm birth and primary-dentition malocclusion and how breastfeeding and the use of pacifiers are related to this association. Methods A representative sample (n = 1129) of children from the 2004 Pelotas, Brazil birth cohort study underwent a dental examination at age 5 years. Malocclusions were diagnosed according to the World Health Organization criteria, and the outcome was considered as the presence of moderate or severe malocclusion (MSM). Questionnaires including the children's oral health information were completed by the mothers. Data on socioeconomic status, breastfeeding, and preterm birth were obtained from previous follow-ups. Poisson regression analysis was conducted, followed by an interaction test. Results The prevalence of MSM was 26.3% (95% confidence interval [CI], 23.6%-29.1%) in the total sample, 24.1% (95% CI, 21.5%-26.