Tooth loss and craniofacial factors associated with changes in mandibular condylar morphology.

Objective: To investigate the association between tooth loss and craniofacial factors with changes in mandibular condylar morphology. Methods: A total of 123 patients participated in this cross-sectional study. The mandibular condylar morphology was evaluated using digital panoramic radiography. The exposure variables included gender, age group, molar relationship, facial growth pattern, facial asymmetry, dental midline, posterior crossbite, presence of fixed dental prosthesis, and tooth loss. Results: Unilateral and bilateral mandibular condyle structural alterations were found in 20.3% and 28.5% of the sample, respectively. After the adjustment analysis, posterior crossbite (adjusted OR = 3.34, 95% CI = 1.23-9.06) and tooth loss (adjusted OR = 4.08, 95% CI = 1.72-9.64) were associated with the outcome. The tooth type associated with mandibular condyle structural alterations were premolars and upper molars. Conclusion: The findings suggest that posterior crossbite and tooth loss are associated with mandibular condyle structural alterations.

Effects of low-level laser therapy on bone regeneration of the midpalatal suture after rapid maxillary expansion.

This study evaluated the effect of low-level laser therapy (LLLT) on bone regeneration at the midpalatal suture (MPS) after rapid maxillary expansion (RME), using cone beam computed tomography. Fourteen 8-14-year-old patients with transverse maxillary deficiency underwent RME with a Hyrax-type expander activated with one full turn after installation and two half turn daily activations until achieving overcorrection. Patients were randomly assigned to either a control group (RME alone, n = 4) or an experimental group (n = 10) in which RME was followed by 12 LLLT sessions (GaAlAs, p = 70 mW, λ = 780 nm, Ø = 0.04 cm(2)). Two tomographic images of the MPS were obtained-T0, after disjunction and T1, after 4 months. Bone regeneration was evaluated by measuring the optical density (OD) on the tomographic images using InVivo Dental 5.0 software. Data were analyzed by the paired Student's t test (α = 0.05 %). A statistically significant difference between T0 and T1 OD values was observed in the laser-treated group (p = 0.00), but this difference was not significant in the control group (p = 0.20). Intergroup comparison of OD values at T1 revealed higher OD in the laser-treated group (p = 0.05). In conclusion, LLLT had a positive influence on bone regeneration of the midpalatal suture by accelerating the repair process.