Extraction vs nonextraction of premolars for orthodontic treatment: A scoping review examining the extent, range, and characteristics of the literature.

INTRODUCTION: The debate about whether malocclusion can or should be treated with or without extraction of premolars continues. This scoping review quantifies the literature, summarizes the outcomes researched and methods, and proposes a way to reduce uncertainty in this area. METHODS: Electronic and gray literature searches were undertaken without language restriction, but non-English language titles and abstracts were not translated. A minimum of 2 people independently screened the titles and abstracts. RESULTS: Searches identified 9010 articles, of which 3851 were duplicates; 5159 were screened, and 4617 were excluded (1092 laboratory or animal studies, 1219 case reports or series, 2306 with no information). By consensus, 399 articles contained information concerning differences between orthodontic patients treated with or without premolar extractions (143 were unclear). The majority (n = 372) reported outcomes in 8 areas. Fifty-seven were review articles (32 systematic reviews and 25 nonsystematic reviews or opinions). The most common research design in the remainder was a cohort (n = 280, 82% of 342 articles reporting primary data), of which a very large majority were considered retrospective (n = 249, 89% of articles reported for subjects over ≥2 time points). Only 28 (8% of articles reporting primary data) were judged to involve prospective data collection (4 randomized controlled trials [RCTs], 23 cohorts, 1 unclear design). Excluding reviews and unclear articles, 99% (332 out of 336) were considered observational research and only 1% were interventional. CONCLUSIONS: There was limited low-quality evidence that extracting premolars in orthodontic patients have a possible negative effect in 2 outcome areas and a positive effect in 1 outcome area. Most study reports were of low methodological quality, and further reviews are unlikely to provide new information. Investigators should concentrate on collecting primary data of outcomes important to patients. A protocol has been made available to help reduce methodological differences, assist future meta-analyses and increase the generalizability of findings: https://doi.org/10.17605/OSF.IO/CQ49Y.

Uprighting a mesially tilted molar using customized titanium healing abutment of an adjacent osseointegrated implant.

This case report evaluates the use of a customized healing abutment of a dental implant to upright a mesially tilted molar using elastic separating rings. The external surface of the healing abutment was roughened by air particle abrasion, and a flowable composite was applied as a collar around it. The size of the resin collar was increased several times during the molar uprighting treatment by replacing the elastic ring. The uprighting procedure was evaluated after 2 months using radiographic and clinical evaluations. After treatment, the mesiodistal space above the implant was increased from 6 mm to 9 mm as follows: 2 mm by uprighting the second molar and 1 mm by mesial shifting the second premolar, and then a screw-retained zirconia crown was placed to restore the implant. The healing abutment of the implant can be modified by adding a resin collar and used as orthodontic anchorage for uprighting the adjacent tilted molar to facilitate the prosthetic procedure. Neither special instruments nor an orthodontic background are required for this minor tooth movement.

Development of the Orthodontic Treatment Impact Questionnaire: Cross-sectional validation.

INTRODUCTION: The need to involve patients in developing and evaluating health care interventions is now well-recognized. This study assesses and refines the Orthodontic Treatment Impact Questionnaire for use as a patient-reported outcome in an interventional clinical trial to evaluate and compare any orthodontic interventions. METHODS: The face and content validity of a previously developed questionnaire were tested in 2 focus groups involving adolescents aged 11-17 years. They were wearing a range of orthodontic appliances and at different treatment stages. A similar cross-sectional convenience sample completed the questionnaire during routine appliance adjustment appointments. A Rasch model, using item response theory, was used for item reduction, assessment of the response format, and differential item functioning. Spearman's rank correlation was used to assess construct validity, Cronbach α for internal consistency and reliability, and intraclass correlation coefficient for test-retest reliability. RESULTS: Seven adolescents (4 females, 3 males) were involved in the initial testing; 181 (117 females, 64 males; mean age, 14.7 ± 1.5 years) completed the questionnaire once and 41 twice. The initial measure demonstrated a misfit to the Rasch model. Ten of the original 31 items had disordered thresholds and were removed. The 5-point scale was changed to a 3-point scale. None of the participants demonstrated a misfit to the model. Construct validity (P = 0.480), internal consistency (Cronbach α = 0.827) and test-retest reliability (intraclass correlation coefficient = 0.85; 95% confidence interval, 0.73-0.92) were good. CONCLUSIONS: The initial Orthodontic Treatment Impact Questionnaire was tested and modified using item response theory. The modified questionnaire demonstrated good construct validity, reliability, and internal consistency. Further testing to assess generalizability and longitudinal responsiveness is required.

Efficacy of clear aligner therapy over conventional fixed appliances in controlling orthodontic movement: A systematic review.

OBJECTIVE: The purpose of the current systematic review was to answer the clinical research question "Is Clear Aligner Therapy (CAT) effective in controlling the orthodontic movement?" by bringing together the most up-to-date information about the available evidence for CAT. METHODOLOGY: On January 1, 2023, a search was conducted in PubMed, ERIC, Embase, and CINHAL for any research papers published in the previous 10 years that provided an overview of the PICO questions. Both the titles and abstracts of the selected studies were evaluated independently by two different authors, and if there was any disagreement between the two review authors, a third reviewer was brought in to settle it. RESULTS: Among included studies, three were retrospective non-randomized and two studies were prospective randomized clinical trials. Various authors reported better outcome for fixed orthodontic appliances than for clear aligner treatment (CAT) in relation to mandibular incisor proclination. The mean objective grading system score was better for braces (17) than for CAT (12) with no clinically significant difference, while staging had a significant impact on treatment efficacy. CONCLUSION: The results of this study suggest that clear aligners may be an effective alternative to traditional braces, but more research is needed to confirm these findings and determine the optimal size of future prospective studies evaluating this treatment.

The Prevalence and Categories of Impacted Maxillary Canines: A Radiographic Study.

OBJECTIVES: The current study aims to identify the prevalence of impacted maxillary canines among the Saudi population in the Qassim region. METHODS: A total of 6,946 panoramic radiographs were collected retrospectively and screened by an experienced orthodontist to determine the frequency of impacted maxillary canines. The Statistical Package for the Social Sciences (SPSS) (IBM SPSS Statistics, Armonk, NY, USA) was used to evaluate the significant differences between categorical variables such as gender and the position of impacted teeth. RESULTS: Overall, 4,977 patients were included in the final analysis. There were 2,509 (50.4%) males and 2,468 (49.6%) females. The prevalence of impacted maxillary canines in our sample was 2.7%, with a higher prevalence of impacted maxillary canines in males (n=74, 2.94%) compared to females (n=60, 2.43%). The majority of the impacted canines were unilateral (n=105, 78.4%) compared to bilateral (n=29, 21.6%). CONCLUSION: Impacted maxillary canines were found in 134 out of 4,977 (2.7%) patients. Males (2.94%) demonstrated a higher impaction rate than females (2.43%). However, the difference was not statistically significant.

Revealing the Effect of Impacted Canines on the Adjacent Teeth. A Three Dimensional Study Using CBCT.

Objective: The current cross-sectional study aimed to assess the relationship between impacted maxillary canines and their effect on root resorption of neighboring teeth using cone-beam computed tomography (CBCT). Materials and Methods: The study evaluated the effect of 24 impacted maxillary canines on the adjacent tooth roots. We used a CBCT to evaluate the position and size of the dental follicle of impacted maxillary canines and the severity of root resorption on adjacent teeth. We used a t-test to compare the significant differences between the width of the dental follicle and the severity of root resorption. The inter- and intra-rater agreements were assessed. Results: A number of 12 impacted canines had resorbed the roots of adjacent teeth. Lateral incisors were most affected (83.3%), followed by central incisors (16.7%). Mild root resorption was found in 10 cases, while severe resorption was found in two cases. We found no relation between the size of the dental follicle and the degree of root resorption. The inter- and intra-rater agreements were high. Conclusion: In cases with maxillary impacted canines, special consideration should be directed to the roots of the maxillary lateral incisors. Our findings could not confirm any relationship between the size of the dental follicle width of the maxillary impacted canines and the degree of root resorption of the adjacent incisors. More studies are needed to assess the proximity and path of eruption of impacted maxillary canines and their effect on the neighboring teeth.