AIM: The value of gonial angle indicates the range of steepness as well as the direction of mandibular growth. Exact measurement of right (R) and left (L) gonial angles from a lateral cephalometric radiograph is challenging due to the superimposition of both sides. Thus, the aim of the present study was to assess the potential of determining accurate measurement of R and L gonial angles by employing orthopantomographs (OPGs) and to compare the findings with the measurements obtained from lateral cephalometric radiographs. MATERIALS AND METHODS: A total of 125 standardized panoramic as well as lateral cephalometric radiographs of Libyan subjects were obtained from the orthodontic clinical records (36 males and 89 females). Mandibular inclination was computed by averaging the R and L gonial angles produced by drawing tangents to the inferior border of the mandible and to the distal aspect of the ascending ramus and the condylon on each OPG. Moreover, similar steps were followed to extract the gonial angle from the cephalometric radiographs. RESULTS: Student's paired t-tests revealed no significant discrepancies between the R and L gonial angle values extracted from the OPG (123.88° ± 6.53° and 123.27° ± 6.55°) at P = 0.0.070. The mean values of the gonial angle (average of the R and L mean values) extracted from the OPG (123.58° ± 6.38°) and cephalometric radiographs (125.14° ± 6.23°) were not significantly different (P = 0.084). Furthermore, Pearson's correlation coefficient revealed strong correlation between the value of the gonial angle measured in the cephalometric radiograph and the mean value extracted from the OPG (r = 0.897 at P < 0.001). CONCLUSION: OPGs are as useful as lateral cephalometric radiographs in the assessment of mandibular inclination and steepness in Libyan subjects. They have the added advantage of reducing patient exposure to radiation by cutting the number of radiographs required during diagnosis.

OBJECTIVES: This study was designed to explore whether force magnitude would influence incisor torque control and the overall outcome in patients with bimaxillary protrusion who need mass incisor retraction. MATERIALS AND METHODS: Forty-one female patients (aged > 15 years) with bimaxillary protrusion requiring mass incisor retraction were selected. Two sliding mechanics were utilized, with the elastic group receiving a light force of ~100 g by wearing elastics and the power chain group receiving a moderate force of ~250 g by power chain. Lateral cephalograms obtained before and after treatment were traced and measured. RESULTS: Patients in both groups displayed maxillary protrusion with a similar skeletal class II tendency. A longer treatment time was found in the elastic group. No difference in the distance of incisor tip movement was observed between the two groups; however, a larger inclination of upper incisors was found in the elastic group, indicating less loss of torque. In addition, larger reduction in Sella-Nasion-A and A-Nasion-B angle was observed in the elastic group, which was accompanied by a larger ratio of upper lip retraction to upper incisor retraction as well as more upper lip retraction. CONCLUSIONS: Sliding mechanics with elastics to generate light forces can achieve better torque control with more reduction in skeletal and soft tissue protrusion.

OBJECTIVES: The objective of this study was to compare the shear bond strength (SBS) of new and rebounded orthodontic brackets bonded to the buccal sound and cleaned enamel surfaces using two orthodontic adhesives: resin-modified glass-ionomer (RMGI) and resin-composite. MATERIALS AND METHODS: Forty premolars were randomly allocated into four groups, 10 teeth/group. New and rebonded brackets were bonded to sound and cleaned enamel surface, and then were subjected to thermocycling. The bond strength was determined using a universal testing machine at a crosshead speed of 1 mm/min. Remaining adhesives on enamel after bracket debonding was scored independently by two investigators who were not aware of the four different groups, using adhesive remnant index (ARI). RESULTS: There was a statistical significant difference in SBS of the four groups (P = 0.005). SBS values were significantly higher with cleaned enamel surfaces after adhesive removal compared to sound enamel. SBS was significantly higher for rebonded brackets, when compared with the new brackets. No significant difference was found between the two adhesives types. The level of agreement between the two raters was higher toward the classification of higher categories of ARI (scores 5 and 6) with agreement percentage 91.7% and 100%, respectively. There was more adhesive remained among resin-composite groups. CONCLUSIONS: The bond strength of debonded sandblasted stainless-steel brackets was higher than new brackets. Resin-composite and RMGI orthodontic adhesives used in this study exhibited sufficient SBS values for bonding brackets to sound and cleaned enamel and comparable to each other.

OBJECTIVES: The purpose of this pilot study was to evaluate the root lengths of upper incisors as an indication of the degree of orthodontically-induced apical root resorption following treatment with Smart Track® aligners and compare it with two different fixed orthodontic appliances – regular and Damon brackets – using cone-beam computerized tomography (CBCT). MATERIALS AND METHODS: The sample comprised 33 patients with class I malocclusion and 4–6 mm crowding divided in 3 groups; Group I: 11 patients treated with Smart Track® aligners, group II: 11 patients treated with Damon brackets, and group III: 11 patients with regular brackets. Maxillary incisors teeth lengths were assessed using Dolphin imaging software before and after treatment. All data were analyzed using analysis of variance and t-test. RESULTS: All groups showed statistically significant root resorption, 0–1.4 mm for clear aligners, 0.1–2.3 mm for Damon, and 0–2.5 mm for regular brackets group. However, cases treated with fixed appliance in general showed significantly higher resorption than those treated with Smart Track® aligners (P < 0.05). CONCLUSION: Orthodontically-induced root resorption, as evaluated by root length, is an inevitable drawback with different orthodontic techniques. However, the use of Smart Track® aligners showed less root resorption relative to regular fixed appliances.

OBJECTIVE: To assess and compare the changes in pharyngeal airway space dimensions following orthodontic treatment of skeletal class II and class III facial deformities with premolar extraction. MATERIALS AND METHODS: Sixty pre and posttreatment lateral cephalometric radiographs of patients who underwent fixed orthodontic treatment with premolar extraction were collected. The sample was divided into two groups – 32 patients with skeletal class II and 28 patients with skeletal class III malocclusion. Both groups were subdivided into growing patients (<16 years old) and adults (>16 years old). Nasopharyngeal, palatopharyngeal, and glossopharyngeal airway space dimensions were measured in the pretreatment (T0) and posttreatment (T1) cephalometric radiographs using Dolphin Imaging 11.7 software. Two-way, repeated-measures analysis of variance was used to assess the in-treatment changes. RESULTS: Nasopharyngeal airway dimension showed similar significant increase in class II (P = 0.042) and class III (P = 0.049) patients from T0 to T1, whereas palatopharyngeal and glossopharyngeal dimensions were insignificantly decreased in both groups. However, both malocclusions followed the same pattern of changes in relation to airway dimensions. In addition, no significant statistical difference was found in the airway spaces between growing and adult patients. CONCLUSIONS: Extraction of premolars did not affect the pharyngeal dimensions except those of the nasopharynx, which showed a significant increase after extraction in both groups.

OBJECTIVE: To assess the knowledge of, demand for, and need for the orthodontic specialty in comparison to other dental fields in a sample of Saudi males. MATERIALS AND METHODS: A multiple choice questionnaire was designed to assess participants' knowledge interest, demand, and need for treatment in the following dental specialties: orthodontics, periodontics, prosthodontics, endodontics, and restorative dentistry. Subjects desiring clinical examination underwent further assessment to document their actual needs. In addition to the subjects' age, the frequencies of tooth brushing, dental pain, treatment seeking, and routine checkup were collected. Descriptive statistics and Pearson's Chi-square test were applied to compare the percentages of the knowledge of, demand for, and need for each dental discipline. The significance level was set at P < 0.05. RESULTS: A total of 1566 Saudi males completed the initial survey of dental knowledge, and 1406 subjects then completed the needs checklist. For the assessment of treatment needed, a total of 177 Saudi males were examined. The average age was 31.25 years (±13.44) and 30.61 years (±10.21) for the surveyed and examined groups, respectively. Subjects' interest in orthodontic knowledge (25%) and demand (27.6%) were not significantly different (P = 0.113), unlike the highly significant difference in the need counterpart (62.5%, P < 0.001). Highly significant differences (P < 0.001) were detected between the three outcome frequencies (knowledge interest, demand, and need) within all dental disciplines, except for the endodontic group where there was no significant difference detected (P = 0.625). Further analysis for the differences between each possible pairing of the three outcomes is highlighted. CONCLUSIONS: Subjects' knowledge of orthodontics approximated their treatment demand. However, orthodontic need was significantly much higher. Different patterns of distinction for other dental specialties were detected and described.