Angle Orthodontist最新文献

Objectives: To evaluate whether the quality of orthodontic finishing influences long-term stability of anterior tooth alignment.

Materials and methods: This retrospective study evaluated 38 patients. Data were obtained at the beginning of treatment (T0), at the end (T1), and at least 5 years after T1 (T2). At this point, the individuals were no longer wearing retainers. Anterior tooth alignment was measured using Little's index (LI). Effect on alignment stability was tested with multiple linear regression using LI-T0, LI-T1, intercanine width difference T1-T0, overbite (T1), overjet (T1), age, gender, time without retention, and presence of third molars as predictor variables. Well-aligned (LI < 1.5 mm) and misaligned (LI > 1.5 mm) cases were compared at T2.

Results: At T2, the alignment stability in the upper arch was inversely associated with the alignment quality (R2 = 0.378, P < .001) and directly associated with overbite (R2 = 0.113, P = .008) at T1. Posttreatment changes caused cases finished with poor alignment to become similar to those finished with excellent alignment (P = .917). In the mandible, posttreatment changes were directly associated only with overjet (R2 = 0.152, P = .015) and well-finished cases displayed better alignment than poorly finished cases (P = .011). Other variables showed no significant association.

Conclusions: In arches without retention, better quality of orthodontic finishing does not guarantee the stability of anterior alignment. In the maxilla, long-term changes were more significant the greater the overbite and the better the quality of alignment at end of treatment. In the mandible, changes were not dependent on the quality of finishing but were associated with greater overbite at T2.

Objectives: To assess differences in dental compensation of the incisors and first molars in skeletal Class III patients with roll-, yaw-, and translation-dominant mandibular asymmetries.

Materials and methods: A total of 90 skeletal Class III adult patients (mean age, 22.00 ± 3.31 years; range, 18-37.9 years) with facial asymmetry were enrolled and divided into the roll-, yaw-, and translation-dominant type groups (n = 30 per group). The vertical, transverse, and anteroposterior distances and axial angles of the teeth were measured using cone-beam computed tomography images. The measurements were compared between the deviated and nondeviated sides using a paired t-test and among the three groups using one-way analysis of variance with a Tukey post hoc test.

Results: The roll-dominant groups showed the greatest values for the bilateral difference in the vertical position of the maxillary (2.42 ± 1.24 mm) and mandibular molars (2.23 ± 1.28 mm; P < .001). The transverse deviations of the maxillary (2.19 ± 1.51 mm) and mandibular incisors (-2.11 ± 1.39 mm) were greater in the yaw-dominant groups than those of other groups. Regarding tooth axial angle, the yaw-dominant group showed the greatest tipping of the mandibular incisor (-4.13 ± 3.30°; P < .001).

Conclusions: Dental compensation differed depending on the type of facial asymmetry. The roll-dominant type showed more vertical compensation of the posterior teeth, whereas the yaw-dominant type exhibited more tipping of the molars and incisors. By precisely assessing dental compensation in each asymmetry type, sufficient dental decompensation could be achieved.

Objectives: To evaluate gingival phenotype (GP) and thickness (GT) using visual, probing, and ultrasound (US) methods and to assess the accuracy and consistency of clinicians to visually identify GP.

Materials and methods: The GP and GT of maxillary and mandibular anterior teeth in 29 orthodontic patients (mean age 25 ± 7.5 years) were assessed using probing and US by a single examiner. General dentist and dental specialist assessors (n = 104) were shown intraoral photographs of the patients, including six repeated images, and asked to identify the GP via a questionnaire.

Results: An increasing trend in GT values of thin, medium, and thick biotype probe categories was found, though this was not statistically significant (P = .188). Comparison of probing method to determinations of GT made by US yielded slight agreement (κ = 0.12). Using the visual method, assessors' identification of the second GP determination ranged from poor to moderate agreement (κ = 0.29 to κ = 0.53).

Conclusions: The probe method is sufficient in differentiating between different categories of GP. However, further research is required to assess the sensitivity of the probe method in recognizing phenotypes in the most marginal of cases. Assessors using the visual method lack the ability to identify GP accurately and consistently among themselves.

Objective: To establish consensus recommendations for clinicians to manage white spot lesions (WSLs) during orthodontic treatment.

Materials and methods: Three task force members reviewed the literature to identify best practices for minimizing WSLs during orthodontic treatment. Each draft statement was read to the task force members by a facilitator, followed by voting, accepting, or editing if necessary. The statements were then sent electronically by an independent third party (Magellan Medical Technology Consultants Inc, Minneapolis, Minn) to a previously formed content validation panel consisting of 20 independent private practitioners and clinical academicians for validation.

Results: Twenty-one statements were developed and sent for content validation. While 19 statements achieved a content validation index (CVI) of 0.78, two items did not. These items were edited by the task force members based on qualitative feedback from content validation participants. Each of these revised statements did achieve a CVI of 0.78 on second evaluation from the content validation panelists and therefore were included in this document.

Conclusion: To reduce the risk of WSLs, it is essential to implement individualized caries management measures based on a comprehensive assessment of the patient's oral and systemic health. Effective at-home and professional mechanical and chemical plaque control should be implemented for high-risk orthodontic patients. Fluoride to support prevention and materials such as orthodontic sealants should also be used to provide a physical barrier around the brackets in high-risk patients. By following these guidelines, orthodontic professionals can help promote oral health and minimize the need for restorative treatment.

Objectives: To assess the effect on the retropalatal airway (RPA), retroglossal airway (RGA), and total airway (TA) volumes and cephalometrics (SNA, SNB, ANB, PP-SN, Occl-SN, N-A, A-TVL, B-TVL) after maxillary advancement orthognathic surgery in patients with unilateral cleft lip/palate (UCL/P) using cone-beam computed tomography (CBCT).

Materials and methods: The CBCT scans of 30 patients (13 males and 17 females, 17-20 years old) with UCL/P were evaluated at two time points: preoperative (T1) and postoperative (T2). The interval between T1 and T2 ranged from 9-14 weeks, except for two patients in whom the interval was 24 weeks. Intraexaminer reliability was measured with an intraclass correlation coefficient test. A paired t-test was used to compare the airway and cephalometric measurements between T1 and T2, with a P value of .05 being considered significant.

Results: From T1 to T2, significant increases were found in the volumes of RPA (from 9574 ± 4573 to 10,472 ± 4767, P = .019), RGA (from 9736 ± 5314 to 11,358 ± 6588, P = .019), and TA (from 19,121 ± 8480 to 21,750 ± 10,078, P = .002). In addition, the RGA (from 385 ± 134 to 427 ± 165, P = .020) and TA (from 730 ± 213 to 772 ± 238, P = .016) sagittal area increased significantly. For minimal cross-sectional area (MCA), only the RPA increased significantly (from 173 ± 115 to 272 ± 129, P = .002). All cephalometric changes were statistically significant between T1 and T2 except for SNB.

Conclusions: Maxillary advancement in patients with UCL/P produces statistically significant increases in the retropalatal (volumetric and MCA), retroglossal (volumetric and sagittal), and total (volumetric and sagittal) airways based on data from CBCT imaging.

Objectives: To evaluate the predictability of the Invisalign appliance (Align Technology, Santa Clara, Calif) in leveling the maxillary curve of Spee (COS).

Materials and methods: A retrospective sample of adult subjects treated with the Invisalign appliance between 2013 and 2019 were selected. Patients were treated nonextraction in the maxillary arch and had either Angle Class I or II malocclusions with a minimum of 14 aligners with no bite ramps. Initial, predicted, and actual outcomes were analyzed with Geomagic Control X software (version 2017.0.3; 3D Systems, Cary, NC).

Results: A sample of 53 cases satisfied inclusion/exclusion criteria. Paired t-tests demonstrated a significant difference between mean predicted and actual maxillary COS leveling with a shortfall of 0.11 mm (SD = 0.37; P = .033). Planned intrusion tended to be more accurate posteriorly with an overexpression of 117% for the first molars. Planned extrusion was the least accurate, with the mid-arch demonstrating expressions of -14% to -48%. These teeth intruded despite a prescribed extrusive movement.

Conclusions: The Invisalign appliance did not accurately predict maxillary COS leveling. Planned intrusive movements were overcorrected, and planned extrusive movements were either undercorrected or resulted in intrusion. This effect was most apparent for the upper first molar, which expressed 117% and -48% of planned intrusion and extrusion, respectively.

Objective: To compare the efficacy and efficiency of treatment with clear aligners (CAT) vs fixed appliances (FAT) in adolescents with Class I and II moderate to severe malocclusions.

Materials and methods: One operator's (Garfinkle) cases from 2014 to 2019, started at age 12-18 years, with pre- and posttreatment records were identified and used according to an institutional review board-approved protocol. Records were measured by two calibrated, blinded investigators, aided by software (OrthoCAD [Cadent, Fairview, N.J.], Dolphin Imaging & Management Solutions [Chatsworth, Calif]). Discrepancy index (DI) and cast radiograph evaluation (CRE) scores, treatment duration, number of scheduled and emergency visits, and reported appliance and interarch elastic wear compliance were compared between groups using Wilcoxon rank sum and Fisher's exact tests. Cephalometric superimpositions were completed to evaluate craniofacial growth and dental changes.

Results: Records from 72 cases met the criteria and were included. For the 47 CAT and 25 FAT cases, mean DI (21 ± 5 and 24 ± 8, respectively; P = .20) and CRE (35 ± 10 and 34 ± 9, respectively; P = .90) scores were not significantly different. Other case attributes and reported appliance and interarch elastic wear compliance were also not significantly different. CAT vs FAT cases had significantly smaller treatment durations (24 ± 6 vs 27 ± 5 months; P = .01) and visit numbers (16 ± 5 vs 24 ± 4; P < .01), but emergency visit numbers were not significantly different (2 ± 2 vs 3 ± 2; P = .08).

Conclusions: In adolescents with Class I and II malocclusions and moderate to severe DI scores, on average, CAT vs FAT cases were completed 3 months faster with eight fewer visits, but treatment efficacy was not significantly different.

This case report describes the orthodontic treatment of an 11-year-old patient with three maxillary impacted teeth on the right side. Cone-beam computed tomography showed that these teeth were close together, with the lateral incisor in a lower position, followed by the central incisor, and the canine in a more apical position. Treatment included applying traction to these teeth. A transpalatal arch was used as an anchorage device, and surgical exposure of the lateral incisor was performed for traction with an elastic chain toward the hook welded to the 0.017 × 0.025-inch steel segmented arch. Subsequently, the central incisor was surgically exposed, elastic chains were used, along with a 0.016-inch steel arch with a box loop for correcting the tooth position. The canine spontaneously began to erupt, and a 0.017 × 0.025-inch TMA segmented arch with boot loop was used to control rotation and torque of the canine during its distalization. Once these three teeth were in the arch, treatment was finished in the usual manner. For esthetic improvement, gingivoplasty was performed in the maxillary arch. Eighteen-month follow-up showed that orthodontic treatment allowed preservation of the natural teeth, the contour of gingival support, and avoidance of prosthetic rehabilitation, reestablishing the patient's esthetics and function, with satisfactory stability.