Longitudinal changes of the natural craniofacial and dentoalveolar complex in the fourth decade of life.

INTRODUCTION: This study aimed to longitudinally examine the changes in craniofacial and dentoalveolar regions during the third and fourth decades of life. METHODS: The data from this study constitute the cephalometric films and plaster models of 8 female and 8 male dental students or dentists. The mean chronological ages of the subjects at the first observation period was 22.09 years for females and 22.64 years for males. The material was collected over 3 intervals: 1985-1989, 1998-2000, and 2016-2017. The observation period was approximately 28 years. Acquired cephalometric recordings and dental models were assessed for subjects in their 20s (baseline), 30s, and 40s. Maxillary, mandibular, maxillomandibular, soft-tissue, and dentoalveolar cephalometric variables were measured with a cephalometric analysis software, and dental cast measurements were made with a digital caliper. Changes in the cephalometric films and dental casts were evaluated statistically. RESULTS: Statistical analysis showed that the length of the midfacial region increased with age. The height of the lower face increased significantly in females and the mandible can be seen mildly rotating to the posterior as it increased in length. The nose moved slightly forward and downward in males and females. Upper lip height was significantly increased in females; however, there was a significant reduction in upper lip thickness for males and females. Soft-tissue pogonion measurements showed a significant forward and downward chin movement in females. Overjet was significantly increased in females, whereas the mandibular arch length was significantly decreased for both sexes, although it was more prominent in females. There was a loss of space in the anterior segments of males and females, resulting in increased crowding. However, the loss of space was only significant in the mandible. CONCLUSIONS: We observed significant changes in skeletal, soft-tissue, and dentoalveolar variables of subjects in their third and fourth decades of life. The fact that many changes have occurred throughout this study demonstrates that the process of maturation and aging is ongoing.

The impact of orthognathic surgery on quality of life for class III dentofacial deformities.

In this study, we aim to evaluate the quality of life in patients with Class III deformities after orthognathic surgery. A total of the 40 patients (26 female and 14 male) were included. The mean age of the patients was 24.85. Patients' ages ranged from 20 to 36 years. All patients received orthodontic treatment before surgery. Sagittal split ramus osteotomy was performed for single jaw patients. Le Fort I osteotomy and sagittal split ramus osteotomy was performed for double jaw patients. Patients completed the Oral Health Impact Profile 14 (OHIP-14) and Orthognathic Quality of Life Questionnaire (OQLQ) three times. [Preoperatively (T0), 1st week after orthognathic surgery (T1) and in the 6th - 12th months after orthognathic surgery (T2)]. There was a statistically significant difference in the dimensions of OHIP-14 when the preoperative (T0) score, postoperative 1st week (T1) score and postoperative 6th - 12th month (T3) score are compared among themselves except for psychological discomfort, physical disability, and handicap. OQLQ total score and preoperative (T0) score was greater than the postoperative 1st week (T1) score and the postoperative 1st week(T1) score was greater than the postoperative 6th - 12th month (T2) scores except oral function. When single jaw and double jaw surgeries were compared, no statistically significant difference was found between OHIP-14 and OQLQ total scores for preoperative, postoperative 1st week, and postoperative 6th - 12th months. When both OHIP-14 and OQLQ scores were examined after orthognathic surgery, the OHRQOL of patients with Class III dentofacial deformity improved significantly.

Long-term evaluation of masseter muscle activity, dimensions, and elasticity after orthognathic surgery in skeletal class III patients.

OBJECTIVE: To evaluate changes in the masseter muscle after orthognathic surgery using electromyography (EMG), ultrasonography (US), and ultrasound elastography (USE) in individuals with skeletal class III anomaly over long-term follow-up and compare with a control group. MATERIALS AND METHODS: The study group included 29 patients with class III dentofacial deformities scheduled to undergo orthodontic treatment and orthognathic surgery. The control group included 20 individuals with dental class I occlusion. Assessment of the masseter muscles using EMG, US, and USE was performed before orthognathic surgery (T1) and at postoperative 3 months (T2) and 1 year (T3) in the study group, and at a single time point in the control group. All assessments were performed at rest and during maximum clenching. Masseter muscle activity, dimension, and hardness were analyzed. RESULTS: Electromyographic activity of the masseter muscle during maximum clenching was increased at postoperative 1 year but did not reach control group values. On ultrasonography, the masseter muscle showed minimal changes in dimension at postoperative 1 year compared to preoperative values and remained below control group values. The postoperative increase in masseter muscle hardness at rest and during maximum clenching persisted at postoperative 1 year. CONCLUSION: The results of this study suggest that after orthognathic surgery, additional interventions and much longer follow-up are needed to ensure better muscle adaptation to the new occlusion and skeletal morphology. CLINICAL RELEVANCE: All assessment methods are useful for comprehensively evaluating changes in the masticatory muscles after orthognathic surgery.

Anterior Tooth Size Discrepancy in Class III Surgical Patients.

OBJECTIVE: The purpose of the present study was to specify whether there are mesiodistal tooth size discrepancies in the anterior region in patients with dentoskeletal Class III malocclusion who underwent orthognathic surgery and orthodontic treatment and to assess the relationship between anterior Bolton ratio and dentoskeletal cephalometric measurements. METHODS: The diagnostic dental casts and lateral cephalometric radiographs of 113 nongrowing patients (54 females and 59 males; mean age: 19.96 ± 4.42 years) with dentoskeletal Class III malocclusion who underwent orthognathic surgery and orthodontic treatment were included in the study. The mesiodistal widths of the 6 anterior teeth were measured from dental casts using a digital caliper accurate to 0.01 mm and anterior Bolton ratios were calculated. Lateral cephalograms were digitalized and used to measure 4 skeletal and 4 dental parameters. RESULTS: The mean anterior ratio of Class III surgical patients was 80.1% with a standard deviation of 2.8%. Clinically significant anterior tooth size discrepancies (greater than ±2 standard deviation) were found in 40.7% of the sample, 97.8% of those patients having anterior mandibular tooth excess. No significant correlation was found between the anterior Bolton ratio and cephalometric measurements. CONCLUSION: Clinicians should consider the probability of tooth size discrepancy in the diagnosis and treatment planning of Class III surgical patients and should perform interventions to eliminate these discrepancies during presurgical orthodontic treatment.