The Angle orthodontist最新文献

Objectives: To examine whether clinical cone-beam computed tomography (CBCT) images can be used to assess three-dimensional bone mineral density (BMD) distribution changes in the alveolar bone (AB), reflecting the biological outcomes of orthodontic treatment in adolescent patients.

Materials and methods: CBCT images of 40 patients (28 females and 12 males; initial mean age = 14.42 ± 1.34 years, range, 11.9-17 years) taken before and after orthodontic treatment with full fixed appliances (treatment duration = 20.50 ± 4.03 months) were collected retrospectively. The AB at maxillary first molar locations (FDI 16 and 26) was digitally isolated using imaging software. A frequency plot of gray values proportional to BMD was developed for each AB region. The mean as well as the fifth percentile low and high gray values (low5 and high5) were computed. Changes in AB morphological parameters and cervical vertebral gray values of the same patient were also compared. A paired test was used to compare the parameters before and after orthodontic treatment.

Results: The gray values of the AB and cervical vertebrae significantly increased after orthodontic treatment (P < .02). Changes in AB parameters before and after orthodontic treatment showed significant but weak positive linear relationships with changes in cervical vertebral parameters (0.12 < r2 < 0.48, P < .04).

Conclusions: Rapid growth and bone mineralization in adolescent patients partially contribute to increased AB BMD following orthodontic treatment. These findings provide baseline information for planning orthodontic treatment specific to adolescents.

Objectives: To investigate how smiles and occlusion influence behavioral response and the perception of age.

Materials and methods: Adult laypeople (N = 80; 19-84 years) were asked to "estimate the age" and "select the younger and healthier face" from pretreatment (pre-Tx) and posttreatment (post-Tx) neutral (N) and smiling (S) face photographs of female orthodontic patient models (N = 18; 25-66 years), along with eye tracking. A survey was conducted to monitor subjective perceptions of age. Age estimation toward peers and nonpeers was compared among young (19-39 years), middle-aged (40-59 years), and older adult (≥60 years) participants.

Results: Greater numbers of post-Tx faces were rated as younger than the actual age when compared with pre-Tx faces (P < .001). Post-Tx/S was most frequently selected as looking younger and healthier (P < .001). Fixation time on the mouth region was significantly higher for S than for N during the tasks (P < .001). For older adults, increase in the ratio of being estimated as younger following Tx was significantly higher for peers than for nonpeers (P < .05).

Conclusions: Individuals with ideal occlusion and smiling were more likely to be perceived as younger by others, indicating a positive influence of orthodontic treatment on age perception. Older adults may benefit from orthodontic treatment for improving their smiles and for being judged younger by others.

Objectives: To assess color and fluorescence changes in post-orthodontic white spot lesions (WSLs) using different surface conditioning methods from prior to resin infiltration to a 24-month follow-up.

Materials and methods: Thirty patients, each with a minimum of four WSLs with ICDAS (International Caries Detection and Assessment System) II code 1 and 2 after bracket debonding were included. After baseline (T0), the lesions were randomly divided into four groups: regular brushing, 15% HCl (hydrogen chloride) gel, 37% H3PO4 (phosphoric acid) gel, and Er:YAG (erbium-doped yttrium aluminium garnet) laser. Icon resin infiltration was applied. In the treatment groups, color and fluorescence were reexamined just after the resin infiltration treatment (T1), and after 6 (T2) and 24 months (T3).

Results: There were no significant fluorescence or color changes between the treatment groups for the different time intervals. The control group showed a significantly lower color change from T0 to T2 and T0 to T3 than all the treatment groups whereas, at T2-T3, the control group showed the greatest improvement.

Conclusions: Resin infiltration caused greater esthetic improvement and more revival of the lost fluorescence than daily brushing. HCl gel, H3PO4 gel, and Er:YAG laser are adequate conditioning methods for resin infiltration of post-orthodontic WSLs with ICDAS II code 1 and 2.

Objectives: To compare the effects of injectable platelet-rich fibrin (I-PRF) and low-level laser therapy (LLLT) on the rate and pattern of orthodontic tooth movement, including canine angulation and rotation during en-masse retraction.

Materials and methods: A single-center, single-blind, split-mouth randomized controlled trial was conducted in 33 female patients with Class I bimaxillary protrusion. Patients were assigned into three clusters: I-PRF vs control, LLLT vs control, and I-PRF vs LLLT. After premolar extraction and initial alignment, en-masse retraction was initiated using 150g force nickel-titanium coil springs. I-PRF (0.5 mL/site) was administered at T0 and T1 (2 weeks). LLLT (650 nm, 8 J/cm2, 100 mW Ga-Al-Ar diode laser) was applied at T0, T2 (4 weeks), and T3 (8 weeks). Control sites received no intervention. Digital study models were obtained at T1 (2 weeks), T2 (4 weeks), T3 (8 weeks), and T4 (12 weeks) to measure space closure and canine rotation. canine angulation was assessed on orthopantomograms at T0 and T4. Data were analyzed using mixed-design analysis of variance.

Results: Both I-PRF and LLLT significantly enhanced space closure compared to control (P < .001). LLLT showed the greatest retraction (3.02 ± 0.24 mm), followed by I-PRF (2.82 ± 0.27 mm) and control (1.99 ± 0.42 mm). Group differences were large (η2p = 0.62), and time × group interactions were moderate. Anchorage loss was higher in both intervention groups.

Conclusions: Both adjuncts accelerated en-masse retraction effectively, with LLLT demonstrating a modest but sustained clinical advantage over I-PRF.

Objectives: To compare and quantify anchorage loss during space closure following premolar extraction in matched groups of different facial types.

Materials and methods: Variables such as facial divergency, age, sex, and crowding were considered for cephalometric analysis. Pearson's correlation coefficient was used to determine the strength of the relationship between anchorage loss and facial divergence. Multiple regression analyses were used to investigate the factors associated with variability of anchorage loss.

Results: Average treatment duration was 41.90 ± 12.97 months. The mean anchorage loss was 3.30 ± 1.99 mm, 3.47 ± 1.95 mm, and 3.01 ± 2.39 mm for hypodivergent, normodivergent, and hyperdivergent patients, respectively. No significant differences in the amount of anchorage loss were found among the three facial groups and between sexes. Increasing age and crowding were significantly negatively associated with anchorage loss (P = .02 and < .001, respectively).

Conclusions: Facial divergence does not significantly impact anchorage loss in orthodontic cases involving extractions. Horizontal anchorage loss decreases the mandibular plane angle, but the magnitude may not be clinically relevant. Vertical anchorage loss does not significantly change the mandibular plane angle in premolar extraction cases.

Objectives: To identify pretreatment malocclusion traits that may influence treatment duration and to assess the correlation between these factors and overall treatment duration.

Materials and methods: This retrospective study included 1430 patients who completed orthodontic treatment between July 2013 and March 2022. A comprehensive evaluation of patient records was conducted, and data related to the initial malocclusion and its associated traits were extracted, including 13 parameters such as Angle's classification, overjet, overbite, open bite, and crowding.

Results: Severe overjet (>9 mm) and reverse overjet were significantly associated with longer treatment duration. Increased overbite was also associated with longer treatment duration, with deep impinging overbite requiring an additional 6 months compared with an average overbite (P < .001). Bilateral posterior crossbite significantly increased mean treatment duration by 4.76 months (P < .001). Additionally, a midline shift > 3 mm was associated with a 2.3-month increase in mean treatment duration (P = .009).

Conclusions: Severe malocclusion traits including increased overjet, reverse overjet, deep overbite, and open bite were strongly linked to longer treatment duration. Similarly, crowding, crossbites, and midline shifts also contributed to extended treatment duration. The presence of missing or impacted teeth, particularly impacted canines and central incisors, led to significant delays in treatment.

Objectives: To investigate the morphological and dimensional changes in vacuum-formed retainers (VFRs) after intraoral aging of 3 months and 6 months and to compare changes between VFRs with conventional and modified gingival margin design.

Materials and methods: Forty-one patients were randomly assigned to two groups: conventional design (CD) and modified design (MD). Preuse and postuse digital models of each VFR were imported to Geomagic Control software to assess the morphological and dimensional changes.

Results: In vivo, VFRs underwent significant changes over time. After 3 months, slight expansion of the VFRs was detected, while after 6 months, slight contraction was observed, despite not all parameters resulting in statistically significant differences. No statistically significant differences were found between the CD and MD groups.

Conclusions: Intraoral aging affects the dimensional stability of VFRs. The gingival margin design did not impact the morphological and dimensional stability of VFRs over the observed period.

Objectives: To compare surface wear among three different attachment composite resins over a 6-month follow-up period.

Materials and methods: Intraoral scanning was performed on 28 participants immediately after initial bonding of attachments (T0), and at 1 (T1), 3 (T2), and 6 months (T3) after starting aligner treatment. In Group 1 (N = 154 attachments), Tokuyama Estelite Universal Flow; in Group 2 (N = 166 attachments), Filtek Z350 XT Universal Restorative; and in Group 3 (N = 161 attachments), G-ænial Universal Injectable resins were used for bonding the attachments. The surface wear depth on attachments was measured using superimposed digitized models. Kruskal-Wallis and Friedman tests were used with a significance set at 5%.

Results: As treatment progressed, surface wear increased significantly in all groups (P < .001). The wear amount for Group 3 was significantly greater than that for Groups 1 and 2 at the 3-month period (P < .001). Regarding T0-T3 surface wear, Group 2 (0.03 mm) and Group 3 (0.0609 mm) exhibited significantly greater wear than Group 1 (0.0243 mm; P = .024 and P < .001). Surface wear was also significantly greater in Group 3 than in Group 2 (P < .001). No significant difference was observed in T3-T0 wear values between conventional and optimized attachments within each group.

Conclusions: The wear of orthodontic attachments was greatly influenced by the type of composite resin. During the third and sixth months of the clinical period, G-ænial Universal Injectable resin demonstrated significantly greater surface wear than other resins. After 6 months, Tokuyama Estelite Universal Flow displayed the least surface wear.

Objectives: To investigate whether significant differences existed in the influence among factors considered during the selection process when ranking orthodontic programs and to understand how an individual's race or ethnic background might affect what factors were more important than others.

Materials and methods: A survey was distributed to orthodontic residents to assess overall preferences and differences in desirability of various factors between historically underrepresented racial and ethnic (HURE) and non-HURE applicants.

Results: A total of 115 individuals initiated the survey, and 98 were included for analysis. Sixteen respondents were considered HURE applicants. "Clear aligner therapy training," "good quality of clinical faculty," and "high number of cases started" had the highest mean desirability overall. The most important factors influencing program rank order were "satisfied current residents," "low cost," and "having multiple techniques and treatment philosophies taught." HURE respondents rated "diversity of training of faculty" (P = .0154), "racial and ethnic diversity of current and former residents" (P = .0007), "racial and ethnic diversity of faculty" (P = .0002), "racial and ethnic diversity of patient population" (P = .0131), "male : female ratio of residents" (P = .0225), "participation in care of Medicaid patients" (P = .0251), and "dental school-based program" (P = .0493) higher than their non-HURE counterparts.

Conclusions: Clinical factors are the most important to program applicants. However, HURE applicants place greater importance than non-HURE applicants on characteristics that promote inclusivity and representation of individuals of similar racial and ethnic backgrounds (peers, mentors, and patients).

Objectives: To evaluate the impact of maxillary advancement by distraction osteogenesis (DO) on the pharyngeal airway including the following parameters in patients with cleft lip and palate (CLP), with a secondary focus on long-term changes ≥1 year: palatal pharyngeal space, superior posterior pharyngeal space, middle pharyngeal space, inferior pharyngeal space, epiglottic pharyngeal space, velar angle, velar length, and need ratio.

Materials and methods: A comprehensive search was conducted in Medline through PubMed, Scopus, Cochrane databases, Embase, and Directory of Open Access Journals through October 2024. Studies were assessed for pharyngeal airway changes at three time points: pre-DO (T1), post-DO (T2), and ≥1-year post-DO (T3). Quality was assessed using the National Institute of Health tool for before-after (pre-post) studies with no control group. Meta-analysis was conducted using Cochrane Review Manager (RevMan) Version 5.3. A random effect model assessed the mean difference (MD) in parameters representing the pharyngeal airway at T1, T2, and T3. GRADE criterion assessed the certainty of evidence. The protocol is officially registered with PROSPERO (CRD42023444533). In this systematic review, we followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

Results: The meta-analysis included 10 studies with 135 patients. The included studies ranged from fair to good quality. Significant increases were observed in pharyngeal space post-DO, particularly in superior and middle pharyngeal regions. Slight relapse was noted after 1 year, but overall, airway improvement remained significant. Evidence certainty by GRADE assessment revealed high to moderate evidence except for need ratio (low).

Conclusions: Maxillary advancement by DO significantly improves pharyngeal airway in CLP patients, with minimal relapse after 1 year.