Angle Orthodontist最新文献

Objectives: To compare the development of white spot lesions (WSLs) during fixed orthodontic therapy among a conventional three-step bonding system, a self-etching primer bonding system, and a one-step adhesive bonding system.

Materials and methods: Seventy-five patients were randomly allocated into three groups (group 1, conventional bonding system, n = 25; group 2, self-etch primer, n = 25; group 3, primer mixed with adhesive composite, n = 25). Quantitative light-induced fluorescence (QLF) was used to assess WSL parameters. Images were captured and then analyzed before treatment and at 2 months and 4 months after bond up. Lesion area (pixels), mean fluorescence loss (ΔF), and the number of newly developed WSLs were compared within and among the three groups. The significance level was P ≤ .05.

Results: The mean increase in lesion area was 31.3 ± 2.8 pixels, 38.4 ± 4.3 pixels, and 119.5 ± 5.3 pixels for groups 1, 2, and 3, respectively (P ≤ .001). For ΔF, the loss was 3.3% ± 0.3%, 4.4% ± 0.2%, and 6.6% ± 0.2% for groups 1, 2, and 3, respectively. These changes were significantly different (P ≤ .01 to P ≤ .001). The incidence of newly developed lesions was 9.5 WSLs in group 1, 10 WSLs in group 2, and 15.9 WSLs in group 3.

Conclusions: The lack of primer contributed to the development of a larger number of and more severe WSLs.

Objectives: To determine the expansion rebound deformation (ERD) of clear aligners (CAs) and its biomechanical influence.

Materials and methods: A four-premolar extraction treatment plan was carried out for a patient with 2 CA companies. Thirty-six digitally scanned clear aligners with the corresponding 36 virtually constructed "ideal" aligners were constructed. The arch width and length between pairs of reference landmarks of the scanned CAs and corresponding dentition models were measured. Cone-beam computed tomography data and digital dental models were used for three-dimensional (3D) finite element analysis (FEA) modeling. Thirty-six scanned CA models with the corresponding 36 ideal CA models were constructed. One-way analysis of variance was used to determine the differences among deviation values at tooth level, and paired t-test was used to compare the displacements of teeth between the two group of CAs.

Results: All CAs were wider and shorter than the digital model from which they were constructed. In the scanned CA model group, significant stress was observed in the buccolingual area of the periodontal ligament on posterior teeth, and the corresponding displacements of teeth were also noted. Significantly larger coronal displacements were noted for the lateral incisor, the canine, the second premolar, and the first molar in the scanned CA group (P < .05).

Conclusions: The general trend of ERD of thermoformed CAs was shown. This deformation may cause unforeseen tooth movements and negatively affect treatment outcomes.

Objectives: To evaluate the changes after maxillary molar distalization in Class II malocclusion using the miniscrew-anchored cantilever with an extension arm.

Materials and methods: The sample included 20 patients (9 male, 11 female; mean age 13.21 ± 1.54 years) with Class II malocclusion, treated with the miniscrew-anchored cantilever. Lateral cephalograms and dental models obtained before (T1) and after molar distalization (T2) were evaluated using Dolphin software and 3D Slicer. Superimposition of digital dental models using regions of interest on the palate was performed to evaluate three-dimensional displacement of maxillary teeth. Intragroup change comparisons were performed using dependent t-test and Wilcoxon test (P < 0.05).

Results: The maxillary first molars were distalized to overcorrected Class I. The mean distalization time was 0.43 ± 0.13 years. Cephalometric analysis demonstrated significant distal movement of the maxillary first premolar (-1.21 mm, 95% confidence interval [CI]: -0.45, -1.96) and maxillary first (-3.38 mm, 95% CI: -2.88, -3.87) and second molars (-2.12 mm, 95% CI: -1.53, -2.71). Distal movements increased progressively from the incisors to the molars. The first molar showed small intrusion (-0.72 mm, 95% CI: 0.49, -1.34). In the digital model analysis, the first and second molars showed a crown distal rotation of 19.31° ± 5.71° and 10.17° ± 3.84°, respectively. The increase in maxillary intermolar distance, evaluated at the mesiobuccal cusps, was 2.63 ± 1.56 mm.

Conclusions: The miniscrew-anchored cantilever was effective for maxillary molar distalization. Sagittal, lateral, and vertical movements were observed for all maxillary teeth. Distal movement was progressively greater from anterior to posterior teeth.

Objectives: To evaluate swallowing function in relation to oropharyngeal dysphagia (OD) in adolescents who had transverse maxillary deficiency with posterior crossbite and high-arched palate, before, and after rapid maxillary expansion (RME).

Materials and methods: Twenty patients (mean age: 13.0 ± 3.1) with bilateral posterior crossbite and high-arched palate (RME group: RMEG) and 20 volunteers (mean age: 13.4 ± 2.6) with Class I crowding without posterior crossbite or high-arched palate (control group: CG) were recruited. OD signs and symptoms were evaluated using the Eating Assessment Tool-10 (EAT-10) questionnaire, patient complaints, and physical examination of swallowing function before (T1) and 7 months after (T2) RME. Additionally, fiberoptic endoscopic evaluation of swallowing (FEES) with water, yogurt, and cracker was performed. In CG, evaluation of swallowing was performed only once, corresponding to T1 of RMEG.

Results: Prevalence of OD signs and symptoms based on patient complaints and physical examination of swallowing was low (5%-15%), and nonsignificant differences were observed between CG and RMEG at T1 for these parameters as well as for EAT-10 scores. Total post-swallow pharyngeal residue with yogurt was significantly different between CG and RMEG at T1, with a prevalence of 60% in RMEG (P < .05). There was no significant difference regarding residue with yogurt between T1 and T2 in RMEG (P > .05).

Conclusion: Patients with a maxillary transverse deficiency were affected by pharyngeal residue as indicated by FEES, but it did not appear to improve in short-term follow-up in patients treated with RME.

Objectives: To investigate the changes made by orthodontists to the initial digital treatment plan (DTP) regarding the Invisalign appliance provided by Align Technology until acceptance of the plan by the orthodontist.

Materials and methods: The DTPs of subjects who underwent treatment with the Invisalign appliance and satisfied inclusion criteria were assessed to determine the number of DTPs and changes regarding prescription of aligners, composite resin (CR) attachments, and interproximal reduction (IPR) between the initial DTP and the accepted plan. Statistical analyses were calculated via GraphPad Prism 9.0 (GraphPad Software Inc., La Jolla, Calif).

Results: Most of the 431 subjects who satisfied inclusion/exclusion criteria were female (72.85%). More DTPs were required for subjects who had orthodontic extractions (median [interquartile range; IQR]: 4 [3, 5]) compared with those who did not (median [IQR]: 3 [2, 4], P < .0001). The median (IQR) overall number of aligners prescribed in the accepted DTP (30 [20, 39]) was greater than the initial DTP (30 [22,41], P < .001). The number of teeth used for CR attachments increased from the initial to the accepted DTP (P < .001). More CR attachments were observed in extraction treatment DTPs with a prescribed 2-week aligner change protocol compared with nonextraction treatment (P < .0001). The number of contact points with prescribed IPR increased between initial and accepted DTPs (P < .0001).

Conclusions: Significant changes regarding DTP protocols were observed between the initial and accepted DTPs and between nonextraction and extraction-based CAT.

Objectives: To compare efficacy of aloe vera and probiotic mouthwashes vs fluoride mouthwash on Streptococcus mutans (S. mutans) in the plaque of orthodontic patients and to assess patient-reported outcomes and compliance.

Materials and methods: This prospective randomized clinical trial included 90 patients aged 12-35 years and in permanent dentition, who were randomly allocated in a 1:1:1 ratio to three mouthwash groups: aloe vera, probiotic, or fluoride. Smartphone-based applications were used to improve patient compliance. The primary outcome was the change in S. mutans levels in plaque between two times: pre-intervention and after 30 days using real-time polymerase chain reaction (Q-PCR). Secondary outcomes were the evaluation of patient-reported outcomes and compliance.

Results: Mean differences between aloe vera vs probiotic: -0.53 (95% CI: -3.57 to 2.51), aloe vera vs fluoride: -1.99 (95% CI, -4.8 to 0.82), and probiotic vs fluoride: -1.46 (95% CI: -4.74 to 1.82) were not significant, P = .467. Intragroup comparison demonstrated a significant mean difference in all three groups of -0.67 (95% CI: -0.79 to -0.55), -1.27 (95% CI: -1.57 to -0.97), and -2.23 (95% CI: -2.44 to -2.00) respectively, P < .001. Adherence was above 95% in all groups. No significant differences in frequency of responses to patient-reported outcomes were found among groups.

Conclusions: No significant difference in efficacy among the three mouthwashes in reducing S. mutans level in plaque was found. Patient-reported assessments concerning burning sensation, taste, and tooth staining found no significant differences among mouthwashes. Smartphone-based applications can help improve patient compliance.

Objectives: To clarify the effect of attachment types on bodily movement of the maxillary canine in aligner orthodontics.

Materials and methods: Using an aligner, the canine was moved bodily by 0.1 mm distally as a target position. Orthodontic tooth movement was simulated using the finite element method (FEM). The alveolar socket was displaced in the same manner as the initial movement caused by elastic deformation of the periodontal ligament. First, the initial movement was calculated, and then the alveolar socket was displaced in the same direction and with the same magnitude as the initial movement. These calculations were repeated to move the teeth after placement of the aligner. The teeth and the alveolar bone were assumed to be rigid bodies. A FEM model of the aligner was made based on the crown surfaces. The thickness of the aligner was 0.45 mm, and its Young's modulus was 2 GPa. Three types of attachments-semicircular couple, vertical rectangular, and horizontal rectangular-were placed on the canine crown.

Results: Regardless of the type of attachment, upon placement of the aligner on the dentition the crown of the canine moved to the target position, while the apex hardly moved. That is, the canine tipped and rotated. After repeating the calculation, the canine became upright and moved bodily regardless of the attachment type. In the aligner without an attachment, the canine did not become upright.

Conclusions: There was almost no difference among attachment types in terms of achieving bodily movement of the canine.

Objectives: To identify and analyze the 50 most cited articles on temporary anchorage devices (TADs) and investigate the achievement and development of scientific research about the topic through a bibliometric analysis.

Materials and methods: On August 22, 2022, a computerized database search was performed to detect papers published in the scientific literature about TADs from 2012 to 2022. Metrics data were identified using the Incites Journal Citation Reports (Clarivate Analytics) data set. The Scopus database was used to obtain information on the authors' affiliations, country of origin, and h-index. Key words were automatically harvested from the selected articles to implement the visualized analysis.

Results: From a total of 1858 papers screened by searching the database, a list of the top 50 most cited articles was created. The total number of citations collected by the 50 most cited articles in TADs was 2380. Among the 50 most cited articles on TADs, 38 were original research papers (76.0%) and 12 were reviews (24.0%). As shown by the key word-network analysis, Orthodontic anchorage procedure was identified as the larger node.

Conclusions: Findings of this bibliometric study showed an increasing number of citations for papers on TADs, accompanied by a simultaneous rise in scientific interest in this topic in the past decade. The present work identifies the most influential articles, emphasizing the journals, the authors, and the topics addressed.

Objectives: To compare palatal dimensions and molar inclinations after Invisalign First System (IFS) to those in patients treated with slow maxillary expansion (SME) and normal controls.

Materials and methods: Twenty-three mixed dentition patients treated with IFS were gender- and dental age-matched to another two groups: Haas-type SME and control group. The intercanine width (ICW), intermolar width (IMW), palatal surface area (SA), volume (V), and first molar buccolingual inclinations (MI) were measured before (T1) and after (T2) treatment. Analysis of variance was used to compare the differences among the three groups.

Results: The ICW increased significantly by 3.10 mm after IFS, 4.77 mm with SME, and 0.54 mm in controls; the difference among the groups was statistically significant (P < .001). The IMW increased by 1.95 mm in IFS, 4.76 mm in SME, and 0.54 mm in controls, with significant intra- and intergroup differences. Palatal SA and volume increased by 43.50 mm2 and 294.85 mm3 in the IFS group, which differed significantly from SME, but was similar to controls. The right and left MI increased 0.24° and 0.08° buccally, respectively, in the IFS group, which was comparable to controls, while significantly increased buccal MI was observed in the SME group.

Conclusions: IFS expands the upper arch with increased ICW and IMW compared to controls, but the expansion amount is smaller than SME. Unlike SME, IFS has no effects on palatal dimensions and molar inclinations.