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Data Sources: The Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Scopus, Web of Science, Google Scholar, Trip, CINAHL via EBSCO, EMBASE via OVID and ProQuest searched up to June 2023. Any clinical study with parallel arms and matched malocclusion severity should include permanent dentition participants with mild to mild-to-moderate anterior crowding. Participants should have undergone orthodontic treatment with either orthodontic labial fixed appliances or removable clear aligners. Total treatment time (primary outcome), chair time, number of appointments, and emergency visits (secondary outcomes) should also be reported., Study Selection: Two reviewers selected the studies to be considered in two stages. If needed, a third reviewer was included to solve discrepancies. Endnote and Rayyan software supported the process., Data Extraction and Synthesis: The same two reviewers independently extracted the required data from the included studies. If needed, a third reviewer was included to solve discrepancies. Endnote and Rayyan software supported the process., Results: Ten studies were finally included (six RCTs and four non-RCTs). Only one included samples in which teeth were extracted due to crowding. The total included sample was 718 participants (aged 20-29 years). Only one study did not report crowding equivalency between groups., Conclusions: Based on low to very low certainty levels, treatment duration is likely similar, chair time and emergency visits are less frequent, and the number of appointments is increased with clear aligners., (© 2024. The Author(s), under exclusive licence to British Dental Association.)

This study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in endochondral development-related genes and mandibular condyle shape, size, volume, and symmetry traits. Cone-beam Computed Tomographies and genomic DNA from 118 individuals were evaluated (age range: 15-66 years). Data from twelve 3D landmarks on mandibular condyles were submitted to morphometric analyses including Procrustes fit, principal component analysis, and estimation of centroid sizes and fluctuating asymmetry scores. Condylar volumes were additionally measured. Seven SNPs across BMP2, BMP4, RUNX2 and SMAD6 were genotyped. Linear models were fit to evaluate the effect of the SNPs on the mandibular condyles' quantitative traits. Only the association between BMP2 rs1005464 and centroid size remained significant after adjusting to account for the false discovery rate due to multiple testing. Individuals carrying at least one A allele for this SNP showed larger condylar size than common homozygotes GG (β = 0.043; 95% CI: 0.014-0.071; P value = 0.028). The model including BMP2 rs1005464, age and sex of the participants explained 17% of the variation in condylar size. Shape, volume, and symmetry were not associated with the evaluated SNPs. These results suggest that BMP2 rs1005464 might be associated with variation in the mandibular condyles size., (© 2024. The Author(s).)

Background: Non-nutritive sucking habits likely may cause occlusal changes such as anterior open bite (AOB) if they persist over extended time., Objectives: To assess if there is self-correction of AOB after cessation of non-nutritive sucking habits in children older than 4 years old, through a systematic review., Search Methods: Data sources included PubMed, Scopus, Web of Science and Latin American and Caribbean Health Sciences (LILACS) databases, gray literature as Google Scholar, the database System for Information on Gray Literature in Europe (OpenGrey) and ProQuest Dissertations and Theses Database, also hand searches of the included studies references., Selection Criteria: Studies assessing occlusal changes in children aged 4-12 years with AOB traits and non-nutritive sucking habits after the discontinuation of the habit were included., Data Collection and Analysis: Two authors independently assessed eligibility and extracted data. The risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale and the Joanna Briggs Critical Appraisal Checklist for quasi-experimental studies. The confidence in cumulative evidence was assessed using the GRADE criteria., Results: Over 3100 studies, only 5 met the inclusion criteria. There is often self-correction of AOB after discontinuing the non-nutritive sucking habit, even in cases older than 4 years old. The improvement ranged between 50 and 100%. The overall quality of evidence was very low., Conclusions: AOB self-correction after discontinuing a non-nutritive sucking habit is possible, even after 4 years old, although with very low certainty in the body of evidence. It is not clear after what age the removal from the habit is unlikely to facilitate AOB self-correction., Registration and Conflict of Interest: International Prospective Register of Systematic Reviews code: CRD42016052171. There was no conflicting interest from the review authors., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Different temporary anchorage device (TAD)-assisted rapid palatal expanders may be used to treat malocclusions involving the transverse dimension and, in many instances, prevent more complex situations in the future. Each style of expander has advantages and disadvantages. The acrylic type of TAD-supported palate lateral wall expander is a reliable and cost-effective appliance for expansion treatment in adolescents and young adults (ie, aged 13 to 21). In comparison, other palatal expander designs are more suitable for older patients. One advantage of an acrylic TAD-supported palate lateral wall expander system is that it can be used for both orthopedic expansions (ie, nonsurgical TAD-supported only) and surgically assisted rapid palatal expansions (ie, with the aid of minimally invasive corticotomies) in patients who do not respond to nonsurgical expansion. This article presents general diagnostic considerations regarding maxillary transverse deficiencies, discusses the importance of palatal expansion in managing malocclusions, and describes protocols for nonsurgical and surgical management of transverse deficiencies with an acrylic TAD-supported virtually guided palate lateral wall expander.

Objectives: To identify malocclusion characteristics generated after using oral appliances (OAs) for at least 5 years for the management of snoring and obstructive sleep apnea (OSA) in adults., Materials and Methods: PubMed, MEDLINE (Ovid), Scopus, CINAHL, and Informit were searched without language restrictions through January 20, 2021. Unpublished literature was searched on ClinicalTrials.gov, the National Research Register, and the Pro-Quest Dissertation Abstracts and Thesis database. Authors were contacted when necessary, and reference lists of the included studies were screened. Risk of bias was assessed through the revised Cochrane Risk of Bias tool for randomized controlled trials (RoB2) and Non-Randomized Studies of Interventions for non-RCTs and uncontrolled before-after studies (ROBINS-I). A random-effects meta-analysis was conducted only on studies that used the same OAs to exclude biomechanical differences. Risk of bias across studies was assessed with the Grading of Recommendations, Assessment, Development and Evaluation tool., Results: A total of 12 studies were included in the final qualitative synthesis. Eight included studies had high, one had moderate, and three had low risks of bias. Significant progressive decreases of overjet (OJ; -1.43 mm; 95% confidence interval [CI], -1.66 to -1.20) and overbite (OB; -1.94 mm; 95% CI, -2.14 to -1.74) associated with maxillary incisor retroclination and mandibular incisor proclination were reported long term. Although most studies showed no sagittal skeletal changes, some degree of vertical skeletal changes were noted., Conclusions: Based on a very low evidence level, inevitable anterior teeth positional changes seem to be a common long-term adverse effect of OAs. The magnitude of those changes could be considered clinically irrelevant for most pretreatment occlusions, but in occlusions with limited OJ and OB, it may be worth clinical consideration., (© 2022 by The EH Angle Education and Research Foundation, Inc.)

Introduction: The objective of this research was to evaluate the effect of orthodontic extraction on the pharyngeal airway volume and Minimum cross-sectional area (MCA) in growing and adult patients., Methods: Seven databases, unpublished gray literature, and the references list of the identified articles were electronically searched for relevant studies that met our eligibility criteria. Included studies assessed the effect of dental extraction or sagittal dental movements on pharyngeal airway dimensions. The quality of the included studies was assessed using the methodological index for nonrandomized studies. In addition, a meta-analysis was conducted using the RevMan 5 (Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen, Denmark)., Results: In 7 studies, 268 treated patients with a mean age of 19.1 ± 7.6 years and 342 nonextraction control group subjects with a mean age of 19.3 ± 7.2 years were included. Compared with the control group, no statistically significant difference was found in total, nasopharyngeal, glossopharyngeal, oropharyngeal volume, or MCA (P >0.05) in the extraction group except in oropharyngeal volume in which a statistically significant increase in the volume 0.41 cm 3 (95% CI, 0.05-0.80; P = 0.03) was detected. The clinical significance of this increase is questionable. Included studies showed a moderate to high risk of bias., Conclusions: There is no strong evidence to support the concept that premolar extractions in bimaxillary protrusion or crowded growing and adult patients reduce either pharyngeal airway volume or MCA. Moreover, as the level of evidence was considered very low for all variables, the magnitude, and direction of the summaries have to be interpreted with caution. Future studies with better quality could significantly affect the direction and strength of the results., Trial Registration Number: PROSPERO CRD42018089924., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

This study aimed to develop and validate the Malocclusion Impact Scale for Early Childhood (MIS-EC), a malocclusion-specific measure of oral health-related quality of life (OHRQoL) of children aged 3-5 years and their parents/caregivers. A pool of items was analysed to identify those relevant to the assessment of the impact of malocclusion on OHRQoL. Dental professionals and mothers of children with and without malocclusion rated the importance of these items. The final version of the MIS-EC was evaluated in a cross-sectional study comprising 381 parents of children aged 3-5 years to assess construct validity, internal consistency and test-retest reliability. Twenty-two items were identified from item pooling. After item reduction, eight items were chosen to constitute the MIS-EC, in addition to two general questions. The MIS-EC demonstrated good internal consistency (Cronbach's alpha = 0.79 for the Child Impact section and 0.53 for the Family Impact section), and excellent test-retest reliability (ICC = 0.94), floor effect was 55.7% and ceiling effect 0%. MIS-EC scores indicating worse OHRQoL were significantly associated with the presence of malocclusion (p < 0.05). The MIS-EC is reliable and valid for assessing the impact of malocclusion on the OHRQoL of preschool children and their parents/caregivers.

Introduction: It has been suggested that heat-activated NiTi archwires (HANT) speed up crowding alleviation. HANT wires are available with different austenite finish temperatures., Objective: The aim of the present study was to compare the effectiveness of two alignment sequences using thermally activated archwires with different austenite activation temperatures for the correction of mandibular anterior crowding., Material and Methods: The following NiTi archwire sequence was used for both groups: 0.012 in (conventional NiTi), 0.018 in (heat-activated NiTi archwires), 0.016×0.022 in (heat-activated NiTi archwires) and 0.019×0.025 in (conventional NiTi). The conventional NiTi used for both groups belongs to the same commercial brand. Two different austenite activation temperatures (35°C and 37°C) were used for the heat-activated archwires. The primary outcome was the degree of crowding correction measured on study models. The secondary outcome was crowding survival time over a six-month period. This RTC included fifty-four patients that were randomly allocated to the two different archwire sequences. A Mann-Whitney test was used to compare the groups regarding crowding alleviation. A survival curve was created using the Kaplan-Meier method to illustrate the reduction of crowding over time. A Mantel-Cox log-rank test was used to compare survival times (until correction of crowding)., Results: No differences in crowding alleviation were identified between both groups (log-rank test; P=0.77)., Conclusions: The two alignment sequences with different thermal activated archwires at 35°C and 37°C achieved similar clinical results during the correction of mandibular anterior crowding., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Objective: To compare removable and fixed orthodontic devices in the correction of non-skeletal anterior crossbite in children and adolescents in the mixed dentition., Materials and Methods: Electronic searches were conducted in the following databases: PubMed, Web of Science, Scopus, Medline Ovid, Lilacs, US Clinical Trials, and Proquest. A hand search of the reference lists of the included articles and a Google Scholar search were also conducted. References were evaluated by 2 review authors. Articles that met the eligibility criteria were included. Data extraction, methodological quality assessment (Cochrane tool), and strength of the evidence evaluation (GRADE) were also carried out., Results: Seven articles were included. The results showed that removable and fixed devices were equally efficacious for overjet correction. Removable and fixed devices can also present inconveniences regarding pain and discomfort levels, the accomplishment of everyday activities (leisure and school), and the performance of functions, such as chewing and speech. However, treatment time and costs were significantly lower in orthodontic therapy with fixed appliances. Sequence generation, allocation concealment, and complete outcome data were not a concern. Blinding of participants or personnel was not reported in any article, and blinding of the assessor was a concern in 2 articles. Selective reporting was a concern in 2 articles. The certainty of the evidence for overjet correction was very low., Conclusion: Removable and fixed orthodontic devices are efficacious for overjet correction in non-skeletal anterior crossbite. However, treatment time and costs are lower for cases treated with fixed devices., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The aim of this systematic review was to identify, evaluate, and provide a current literature about the influence of heritability on the determination of occlusal traits., Materials and Methods: MEDLINE, SCOPUS, Web of Science, LILACS, and Google Scholar were searched without restrictions up to March 2020. Studies with twin method were considered and the risk of bias assessment was performed using quality of genetic association studies checklist (Q-Genie). The coefficient of heritability (h 2 ), model-fitting approaches, and coefficient correlation were used to estimate the genetic/environmental influence on occlusal traits. The GRADE tool was used to assess the quality of the evidence., Results: Ten studies met the eligibility criteria. Three studies presented good quality, five moderate quality, and two poor quality. Most studies have found that the intra-arch traits, mainly the maxillary arch morphology, such as width (h 2 16-100%), length (h 2 42-100%), and shape (h 2 42-90%), and the crowding, mainly for mandibular arch (h 2 35-81%), are under potential heritability influence. The traits concerning the inter-arch relationship, as overjet, overbite, posterior crossbite, and sagittal molar relation, seem not to be genetically determined. The certainty of the evidence was graded as low for all outcomes., Conclusions: Although weak, the available evidence show that the heritability factors are determinant for the intra-arch traits, namely, arch morphology and crowding. Possibly due they are functionally related, the occlusal traits concerning the maxillary and mandibular relationship seem to have environmental factors as determinants. In this scenario, early preventive approaches can offer a more effective and efficient orthodontic treatment.

Objective: To analyse through a systematic review the effectiveness of clear aligners by assessing: (a) predictability of clear aligners and (b) treatment outcome comparison of clear aligner therapy with fixed appliance therapy., Methods: An electronic search was made from January 2014 to April 2019 using MEDLINE, Embase, Web of Science and LILACS databases without any limitations on language. Three reviewers independently assessed the articles. Quality assessment of observational studies and randomized control trial was done by using the ROBINS tool and Cochrane risk of bias tool, respectively. GRADE instrument was used to assess certainty level for each identified outcome., Results: Seven eligible articles (one randomized controlled trial and six retrospective cohort) were included in our systematic review. Most of the studies (six out of seven) had a moderate risk of bias and one had a high risk of bias., Conclusions: 'Low to moderate level' of certainty in regard to specific clear aligner therapy tooth movements' efficiency was identified. Clear aligners may produce clinically acceptable outcomes that could be comparable to fixed appliance therapy for buccolingual inclination of upper and lower incisors in mild to moderate malocclusions. However, not all potential clinical scenarios have been assessed in the included studies. Most of the tooth movements may not be predictable enough to be accomplished with only one set of trays with clear aligners despite the recent advances in technology., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To compare the skeletal and dentoalveolar changes produced by the Damon system's treatment philosophy to traditional orthodontic treatment techniques., Materials and Methods: An electronic search in four major databases was completed: Cochrane, PubMed, EMBASE, and Google Beta Scholar on October 5th, 2018. Randomized controlled trials, prospective and retrospective controlled clinical trials were included in this systematic review. The quality assessment of individual studies was done using two different tools: The Cochrane Risk of Bias Assessment Tool (RTCs) and The Methodological Index for Non-Randomized Studies (MINORS) (non-RCTs)., Results: Seven studies were included for this qualitative analysis. Six studies compared the Damon system to various types of conventional (non self-ligating bracket) system as a comparison group. One study used a quad helix as a comparison for a few months before a full bonding appointment with conventional brackets. The majority of studies found an increase in maxillary inter-canine, inter-premolar, and intermolar distance after the treatment in both the Damon and comparison groups. Yet, all studies concluded that there is no significant difference in the final transverse dimension between the two groups. One study also found that the transverse expansion was achieved mainly by tipping movement of posterior dentition, and a decrease in the posterior buccal bone area was evident in both groups after treatment., Conclusion: There is not enough evidence to support the claim that the Damon system allows additional arch expansion with better tipping control than with traditional techniques., (Copyright © 2019 CEO. Published by Elsevier Masson SAS. All rights reserved.)

Article Title and Bibliographic Information: Malocclusion in young children. Does breast-feeding really reduce the risk? A systematic review and meta-analysis. Doğramacı EJ, Rossi-Fedele G, Dreyer CW. J Am Dent Assoc 2017; 148(8):566-74., Source of Funding: Australian Government Research Training Program Scholarship TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: To compare the short-term skeletal and dental effects of two-phase orthodontic treatment including either a Twin-block or an XBow appliance., Materials and Methods: This was a retrospective clinical trial of 50 consecutive Class II cases treated in a private practice with either a Twin-block (25) or XBow (25) appliance followed by full fixed orthodontic treatment. To factor out growth, an untreated Class II control group (25) was considered., Results: A MANOVA of treatment/observation changes followed by univariate pairwise comparisons showed that the maxilla moved forward less in the treatment groups than in the control group. As for mandibular changes, the corpus length increase was larger in the Twin-block group by 3.9 mm. Dentally, mesial movement of mandibular molars was greater in both treatment groups. Although no distalization of maxillary molars was found in either treatment group, restriction of mesial movement of these teeth was seen in both treatment groups. Both treatment groups demonstrated increased mandibular incisor proclination with larger increases for the XBow group by 3.3°. The Wits value was decreased by 1.6 mm more in the Twin-block group. No sex-related differences were observed., Conclusions: Class II correction using an XBow or Twin-block followed by fixed appliances occurs through a relatively similar combination of dental and skeletal effects. An increase in mandibular incisor inclination for the XBow group and an increased corpus length for the Twin-block group were notable exceptions. No overall treatment length differences were seen.

Objective: The objective of this study was to evaluate the Björk and Jabarak cephalometric analysis generated from cone-beam computed tomography (CBCT) synthesized lateral cephalograms in adults with different sagittal skeletal patterns., Methods: The sample consisted of 46 CBCT synthesized cephalograms obtained from patients between 16 and 40 years old. A Björk and Jarabak cephalometric analysis among different sagittal skeletal classes was performed. Analysis of variance (ANOVA), multiple range test of Tukey, Kruskal-Wallis test, and independent t-test were used as appropriate., Results: In comparison to the standard values: Skeletal Class III had increased gonial and superior gonial angles (P < 0.001). This trend was also evident when sex was considered. For Class I males, the sella angle was decreased (P = 0.041), articular angle increased (P = 0.027) and gonial angle decreased (P = 0.002); whereas for Class III males, the gonial angle was increased (P = 0.012). For Class I females, the articular angle was increased (P = 0.029) and the gonial angle decreased (P = 0.004). Björk's sum and Björk and Jabarak polygon sum showed no significant differences. The facial biotype presented in the three sagittal classes was mainly hypodivergent and neutral., Conclusions: In this sample, skeletal Class III malocclusion was strongly differentiated from the other sagittal classes, specifically in the mandible, as calculated through Björk and Jarabak analysis.

Background: The aim of this study is to evaluate the nature and frequency of incidental findings in large-field maxillofacial cone beam computed tomography (CBCT)., Methods: A total of 427 consecutive CBCT radiologic reports obtained for orthodontic purposes were retrospectively reviewed. Findings were summarized and categorized into six anatomic categories., Results: A total of 842 incidental findings were reported in the 427 CBCT scans (1.97 findings/scan). The most prevalent findings were those located in the airway (42.3%), followed by the paranasal sinuses (30.9%), dentoalveolar (14.7%), surrounding hard/soft tissues (4.0%), temporomandibular joint (TMJ) (6.4%), and cervical vertebrae (1.3%) regions. Non-odontogenic findings, defined as those located outside the dentition and associated alveolus, represented 718 of the 842 (85.3%) findings., Conclusions: This study confirms the high occurrence of incidental findings in large-field maxillofacial CBCT scans in a sample of orthodontically referred cases. The majority are extragnathic findings, which can be normally considered outside the regions of interest of many dental clinicians. Specifically, incidental findings in the naso-oropharyngeal and paranasal air sinuses are the most frequent. This underscores the need for comprehensive review of the entire data volume and the requisite to properly document all findings, regardless of the region of interest.

Background: Several indices are now available to assess the severity of the malocclusion in cleft lip and/or palate (CLP) patients; and although it has been quite some time since the introduction of these indices, there is no consensus as to which index should be used for CLP populations., Objective: To systematically review the available literature on the indices used to assess the occlusal schemes in dental models of CLP patients, with respect to the most commonly used index and the index that most fulfils the World Health Organization (WHO) criteria., Search Methods: Ten electronic databases, grey literature, and reference list searches were conducted., Selection Criteria: The inclusion criteria consisted of studies that aimed to assess a particular malocclusion index on study models of patients with CLP., Data Collection and Analysis: Full articles were retrieved from abstracts/titles that appeared to have met the inclusion -exclusion criteria which were subsequently reviewed using more detailed criteria for a final selection decision. The Quality Assessment of Diagnostic Accuracy Studies tool was used to appraise the methodological quality of the finally included studies. Due to the heterogeneity of the data, only a qualitative analysis was performed., Results: A total of 13 studies met the inclusion -exclusion criteria. These studies revealed seven utilized indices, namely the GOSLON Yardstick, Five-Year-Old, Bauru-Bilateral Cleft Lip and Palate Yardstick, Huddart -Bodenham, Modified Huddart -Bodenham, EUROCRAN Yardstick, and GOAL Yardstick. The GOSLON Yardstick was the most commonly used index, and the Modified Huddart -Bodenham performed the best according to the WHO criteria., Conclusions: Current evidence suggests that the Modified Huddart -Bodenham Index equalled or outperformed the rest of the indices on all the WHO criteria and that the GOSLON Yardstick was the most commonly used index, possibly due to a longer time in use. Therefore, the Modified Huddart -Bodenham could be considered as the standard to measure outcomes of patients with CLP.

Background: The study aims to compare the condylar position in patients with different anteroposterior sagittal skeletal relationships through a cone beam computed generated tomography (CBCT) imaging generated space analysis., Methods: This was a retrospective study of clinically justified, previously taken CBCT images of 45 subjects. Based on a proper sample calculation, three groups of 15 CBCT images each were made according to their ANB angle and facial pattern: class I (normo facial pattern) and class II and III (long facial pattern). The CBCT images were of adult patients between 18 and 35 years old, with full permanent dentition at maximum occlusal intercuspidation. Anatomical references previously used by Ricketts for the condyle position inside the glenoid fossae were measured digitally through the EzImplant software. Analysis of variance, Tukey's, Kruskal-Wallis, and Mann-Whitney U statistical tests were used., Results: The upper distance of the condyle to the glenoid fossa was smaller in the class II and class III compared with the class I group. The anterior distance of the condyle to the articular eminence showed significant differences when comparing the class I with the class II and class III groups. No statistically significant difference was noted in the posterior condylar distance between the groups. The angle of the eminence showed differences between the three groups, while the eminence height showed significant difference when comparing the class I with class III group., Conclusions: Spatial differences existed for the condylar position in relation to the glenoid fossa for skeletal class I, class II, and class III, but these spatial differences may not be clinically relevant.

Purpose: The aim of this systematic review was to investigate the accuracy of computer programs in predicting skeletal changes after orthognathic surgery., Materials and Methods: A systematic computerized database search was conducted with the help of a health sciences librarian. Specific selection criteria were used to select articles, reference lists of the selected articles were also searched for any potential articles that might have been missed in the electronic search, and additional information not available through the articles was obtained directly from the corresponding author., Results: Of the 79 initially identified articles (abstracts/titles), only 9 fulfilled the final selection criteria. As expected, no dental changes occurred but the computer programs were unable to precisely predict all the skeletal changes. Most of the prediction inaccuracies were within 2 mm or 2 degrees , which can be partially attributed to measurement errors in cephalometric tracing., Conclusions: This systematic review showed that computer programs cannot consistently predict the skeletal changes occurring after orthognathic surgery but their results may be considered inside a clinically acceptable range. Last-minute changes by the surgeons could also explain the differences. We also conclude that no software program was shown to be superior in prediction accuracy compared with its competitor.

Purpose: The aim of the present systematic review is to investigate the accuracy of computer programs in predicting soft tissue response subsequent to skeletal changes after orthognathic surgery., Materials and Methods: A systematic computerized database search was conducted using Ovid Medline, Ovid Medline in-process and other nonindexed citations, all EBM reviews (including Cochrane DSR, ACP Journal, DARE, CCTR), Embase Experta Medica, Pascal, and Thomsen's ISI Web of Science databases. The terms orthognathic surgery, orthodontic treatment, computer prediction, computer simulation, growth prediction, accuracy, precision, forecast, and human studies were used for the searches. The reference lists of all the selected articles were also searched for any potential articles that might have been missed in the electronic search of the database, and additional information not available through the articles was obtained directly from the source (by contacting the author)., Results: Out of the 40 initially identified articles only 7 articles fulfilled the final selection criteria. All 7 studies in general showed accurate prediction outcomes (less than 2 mm) when compared with actual results in both horizontal and vertical directions. From all the available computer prediction programs Quick Ceph, DentoFacial Planner (DFP), and Computer-Assisted Simulation System for Orthognathic Surgery (CASSOS) were the most frequently used., Conclusions: The most significant area of error in prediction through the available computer prediction programs was the lower lip area. Although the individual errors are almost always minimal (less than 2 mm), the composite addition of these minimal errors could have clinical implications.

Purpose: The purpose of this study was to consider the available evidence regarding premature loss of primary molars and the implications for treatment planning., Methods: Electronic database searches were conducted--including published information available until July 2007--for available evidence. A methodological quality assessment was also applied., Results: Although a significant number of published articles had dealt with premature primary molar loss, only 3 studies (including a total combined sample of 80 children) had the minimal methodological quality to be considered for this systematic review., Conclusion: A reported immediate space loss of 1.5 mm per arch side in the mandible and 1 mm in the maxilla--when normal growth changes were considered--was found. The magnitude, however, is not likely to be of clinical significance in most cases. Nevertheless, in cases with incisor and/or lip protrusion or a severe predisposition to arch length deficiency prior to any tooth loss, this amount of loss could have treatment implications.

Objective: To determine the individual and combined influence of some anterior occlusal characteristics on self-perceived dental appearance in a sample of young adults., Materials and Methods: This cross-sectional study was conducted at a dental clinic of a private university in Lima, Peru. A total of 267 first-year students (16 to 25 years old) were randomly selected. A visual analog scale (VAS) was used to determine the self-perceived dental appearance. Clinical examinations were conducted to determine incisal irregularity, anterior dentoalveolar spacing, midline diastema, anterior missing teeth, overjet, and overbite. Simple and multiple linear regression analyses were performed to determine the individual and combined influence of each anterior occlusal characteristic on self-perceived dental appearance., Results: From the eight occlusal characteristics and two covariables evaluated, only maxillary and mandible incisal irregularity (P=.001 and .002 respectively), presence of anterosuperior spacing (P<.001), and number of missing anterior teeth (P=.003) were inversely associated with self-perceived dental appearance, whereas gender (male) was directly associated to the dependent variable (P=.021). Specifically, anterior maxillary spacing, maxillary incisal irregularity, mandible incisal irregularity, and the number of missing teeth were, in that order, the anterior occlusal characteristics with the most negative influence on self-perceived dental appearance., Conclusions: This study confirmed that occlusal characteristics in the anterior portion of the mouth play a role on dental esthetics. However, it should be emphasized that their grouped influence is minimal (less than 20%).

Objective: To assess the impact of previously provided orthodontic treatment on the normative need in a sample of young adult Peruvians., Methods: Six hundred and thirty five freshmen, representative of all first year students registering in 2002 at a private university in Lima, were randomly screened to obtain 63 cases and 126 controls. A case was defined as having a definite orthodontic treatment need determined by the DAI and IOTN indices simultaneously. A control was defined as having no need of orthodontic treatment based on both indices. Students were also asked if they had previously undergone any orthodontic treatment. Binary logistic regression was used for the statistical analysis., Results: Sex, age and socioeconomic status of the students were not statistically associated with normative orthodontic treatment need (p = 0.258, 0.556 and > or = 0.272 respectively). The percentage of students with a previous history of orthodontic treatment was similar between the cases and the controls (14.3 per cent and 11 .9 per cent respectively). There were no statistically significant associations between the variables., Conclusions: The impact of previously provided orthodontic treatment on the current normative need of young adults was limited. Properly designed studies are required to assess the reasons for these findings.

Background: Previous studies on orthodontic treatment need in young adults have shown that up to 50% had malocclusions that needed orthodontic treatment. The aims of this study were to assess the normative and self-perceived need for orthodontic treatment using the Index of Orthodontic Treatment Need (IOTN) and to determine if the treatment need levels were influenced by sex, age and socio-economic status (SES) in a sample of Peruvian young adults., Methods: 281 first-year students (157 male and 124 female students) with a mean age of 18.1 +/- 1.6 years were randomly selected and evaluated through the Dental Health Component (DHC) and Aesthetic Component (AC) of the IOTN. Structured interview and clinical examination were used to assess the students. Descriptive statistics and Chi-square tests were used for data analysis with statistical significance set at P < 0.05., Results: An intra-examiner reliability of 0.89 was obtained (weighted Kappa). The percentage of students according to SES was 51.2%, 40.6% and 8.2% corresponding to low, medium and high SES respectively. The percentage of students with DHC grades 4-5 was 29.9% whereas the percentage of students with AC grades 8-10 was 1.8%. There were no significant differences in the distribution of normative and self-perceived orthodontic treatment need based on sex, age and SES comparisons., Conclusion: Normative orthodontic treatment need was not matched by a similar level of self-perceived treatment need in these young adults. Sex, age and SES were non-significant factors associated with levels of treatment need.

Introduction: The objective of this validation study was to compare standard plaster models (the current gold standard for cast measurements) with their digital counterparts made with emodel software (version 6.0, GeoDigm, Chanhassen, Minn) for the analysis of tooth sizes and occlusal relationships--specifically the Bolton analysis and the peer assessment rating (PAR) index and their components., Methods: Dental casts were poured from 24 subjects with 8 malocclusion types grouped according to American Board of Orthodontics categories. Measurements were made with a digital caliper to the nearest 0.01 mm from plaster models and with the software from the digital models. A paired samples t test was used to compare reliability and validity of measurements between plaster and digital methods., Results: Reproducibility of digital models via the concordance correlation coefficient was excellent in most cases and good in some. Although statistically significant differences in some measurements were found for the reliability and validity of the digital models via the average mean of the absolute differences of repeated measurements, none was clinically significant. Grouping of the measurements according to the 8 American Board of Orthodontics categories produced no significant difference (Kruskal-Wallis test). No measurement associated with Bolton analysis or PAR index made on plaster vs digital models showed a clinically significant difference. The PAR analysis and its constituent measurements were not significantly different clinically between plaster and emodel media., Conclusions: Preliminary results did not indicate that digital models would cause an orthodontist to make a different diagnosis of malocclusion compared with plaster models; digital models are not a compromised choice for treatment planning or diagnosis.

The aim of this study was to determine which dental esthetic self-perception evaluation tool discriminated better between orthodontically treated or untreated Peruvian young adults. A total of 630 students were randomly chosen from the 2000 admitted in 2002 to a private university in Peru. Students undergoing active orthodontic treatment at the time of examination were excluded. Self-perceived dental esthetic appearance was evaluated through Standardized Continuum of Aesthetic Need, Oral Aesthetic Subjective Index Scale, and Visual Analogue Scale (VAS). A stepwise multivariate discriminant analysis was developed to classify orthodontic treatment according to the three evaluation tools. A total of 199 students (31.6%) reported a history of orthodontic treatment. Differences between orthodontically treated and untreated groups were found only for the mean VAS score (P < .001). Although three different approaches were used to evaluate dental esthetic self-perception, only VAS allowed the discrimination of the self-perceived dental appearance between orthodontically treated and untreated Peruvian university young adults. Similarities in the self-perceived dental appearance of treated and untreated groups reported in previous epidemiological studies could be explained because different evaluation instruments were used. Further studies are required to support current findings.

The objectives of this study were to evaluate the frequency and severity of the malocclusion and treatment needs in Peruvian young adults. The second aim was to compare the orthodontic treatment needs according to sex and socio-economic status (SES). This cross-sectional study was conducted at the University Dental Clinic of a private university in Lima, Peru. A total of 267 freshmen (from 16 to 25 years old) were randomly selected from a pool of 780 students. Students wearing an orthodontic appliance or reporting a history of orthodontic treatment were excluded from the study. Clinical examinations were conducted using the Dental Aesthetic Index (DAI). Mann-Whitney and Kruskal-Wallis tests were used to compare the DAI scores according to sex and SES, respectively. The mean DAI score was 28.87 points (IC(95%) 27.77; 29.97, where IC indicates interval of confidence). Around one-third of the sample presented severe or very severe malocclusion, which implies a highly desirable or mandatory orthodontic treatment need. No statistically significant difference was found between the DAI scores according to sex (P = .592) and SES (P = .397). Approximately one-third of the evaluated Peruvian young adults would need orthodontic treatment according to the DAI. In this population, malocclusion was characterized by a relatively high frequency of missing teeth, appreciable dental crowding, and inadequate anteroposterior relationships.

The objective of this study was to compare, combined and individually, the mesiodistal (MD) and buccolingual (BL) tooth sizes as well as their respective crown proportions in the permanent dentition in dental arches with moderate, mild, and no crowding. Dental casts from two-hundred 12 to 16-year-old school children from a typical high school from Lima, Peru, were used. The MD and BL tooth sizes of all permanent teeth except second and third molars were measured, and their crown proportion (MD/BL ratio) was estimated. Each dental arch was classified as presenting moderate (-5.1 mm or more of discrepancy), mild (-0.1 and -5 mm of discrepancy), and no crowding (zero or a positive discrepancy). Combined and tooth-specific comparisons among the crowding groups for the tooth sizes as well as crown proportions were performed with a multivariate analysis of variance (MANOVA, using Wilks lambda). Combined MD tooth sizes and crown proportions differed among crowding groups. Subsequent individual comparisons indicated differences for MD tooth size of all upper teeth and for lower premolars and central incisors. Differences were also detected for crown proportions of the upper second premolar, canine, and both incisors; as well as for the lower first premolar, canine, and central incisor. No differences were found for the BL tooth sizes among crowding groups. MD tooth sizes and crown proportions from specific teeth are significantly different between dental arches with moderate, mild, and noncrowded arches. This study helps to understand the odontometric component of the dental crowding multifactorial origin.

Objective: To analyze 6 different types of visible anterior occlusion, exclusive of extraoral facial features, in terms of their esthetic appeal, as perceived by 91 randomly selected adult laypersons with different levels of education in Lima, Peru., Methods: Photographic images of 3 examples of each occlusion type (open bite [OB], deep bite [DB], crossbite [CB], end-to-end bite [EE], crowded bite [CwB] and ideal bite [IB]) were prepared. Evaluators used a visual analogue scale (VAS) to rate their perceptions of the esthetic appeal of each view. Analysis of variance (ANOVA) was used to test differences in mean scores among occlusion types and to test the effect of evaluator characteristics on perceived attractiveness., Results: The mean score was highest for IB, followed by EE, DB, CB, CwB and OB. Oneway ANOVA with Bonferroni post hoc test showed no difference between the highestscoring occlusion types (IB and EE, p > 0.99); each of the remaining groups was significantly different from both IB and EE (p < 0.001). The scores for DB, CB, CwB and OB were progressively lower, although not significantly different from one another (p > 0.05). Univariate ANOVA to determine the effects of evaluator characteristics (age, level of education, gender and interaction between level of education and gender) showed that gender was a significant factor (p < 0.034) for all bite groups except OB. Level of education was significant only for OB (p = 0.020) and age only for EE (p = 0.011). The interaction between level of education and gender was significant for all bite types (p < 0.046)., Conclusions: Lay evaluators identified ideal and EE bite occlusal relationships as esthetically most pleasing. They judged DB, CB, CwB and OB bite relationships as less esthetically pleasing but did not differentiate between these types of malocclusions.

Introduction: The objective of this study was to identify the intra-arch occlusal characteristics that best discriminated 3 groups with different grades of dental arch discrepancies. This cross-sectional analysis was conducted in Lima, Peru, in 2003., Methods: Intra-arch measurements were made on 150 sets of dental casts of high school students (aged 12-16; 75 boys, 75 girls). Stepwise multiple discriminant analysis (SMDA) was used to obtain a better understanding of the morphological relationships between tooth and dental-arch variables and their relationship with crowding., Results: Mesiodistal tooth sizes and crown proportions of some teeth differed among significantly crowded, mild-to-moderately crowded, and spaced dental arches. Buccolingual tooth sizes were similar in the 3 groups. Of the arch dimensions evaluated, only intermolar arch width and arch length differed between the groups. An SMDA was developed to classify dental-arch discrepancies in the permanent dentition based on several intra-arch occlusal characteristics. The variable with the highest discriminatory capability between groups was arch length. When arch length was taken out of the SMDA, the explanatory capability from the variability on the dental arch discrepancies diminished from 51% to 14%. When the remaining arch dimension variable (intermolar width) was taken out, the explanatory capability diminished more (from 14% to 8%)., Conclusions: Although other tooth-size and arch dimensions are indicators of crowding, arch length is the most important factor.

Introduction: The purpose of this meta-analysis was to quantify the amount of true incisor intrusion attained during orthodontic treatment., Methods: Electronic databases (PubMed, Medline, Medline In-Process & Other Non-Indexed Citations, all EBM reviews [Cochrane Database of Systematic Reviews, ASP Journal Club, DARE, and CCTR], Embase, Web of Science, and Lilacs) were searched with the help of a senior health sciences librarian. The goal was to identify clinical trials that assessed true incisor intrusion through cephalometric analysis and factored out craniofacial growth when required. From the selected abstracts, original articles were retrieved, and their references were hand searched for missing articles., Results: Twenty-eight articles met the initial inclusion criteria, but 24 were rejected because they did not quantify true incisor intrusion or factor out normal growth impact when required. The remaining 4 articles showed that true incisor intrusion is attainable (0.26 to 1.88 mm for the maxillary incisors and -0.19 to 2.84 mm for the mandibular incisors) but with large variability depending on the appliance used. A meta-analysis with results from the 2 articles that used the segmental technique was completed. The combined mean estimates of intrusion and 95% CI were 1.46 mm (1.05-1.86 mm) for the maxillary incisors and 1.90 mm (1.22-2.57 mm) for the mandibular incisors., Conclusions: True incisor intrusion is achievable in both arches, but the clinical significance of the magnitude of true intrusion as the sole treatment option is questionable for patients with severe deepbite. In nongrowing patients, the segmented arch technique can produce 1.5 mm of incisor intrusion in the maxillary arch and 1.9 mm in the mandibular arch.

Discrepancies in tooth width ratios could affect the excellence in the finishing of orthodontic cases. This study compares tooth width ratios in crowded and noncrowded dental arches. Tooth widths were measured from 143 dental casts (40 crowded and 33 spaced in male individuals and 43 crowded and 27 spaced in female individuals). Simultaneous crowded or spaced arches were selected. Tooth width measurements were made with a sliding caliper with a Vernier scale neared 0.1 mm. Inter- (0.990) and intraexaminer (0.993) reliability with mean differences of 0.03 mm (-0.03; 0.07) and 0.01 mm (-0.04; 0.05), respectively, were attained. Bolton analysis was applied to calculate the tooth width ratios (anterior and total). Descriptive statistics, Student's t-test, and analysis of variance were applied. There was no significant difference between the anterior and total tooth width ratios according to sex (P > .05). Both anterior and total ratios were significantly greater in subjects with crowding (P = .003 and P = .026, respectively), but no statistical difference by arch type in anterior and total tooth mass excess was found (P > .05). Differences among subjects with noncrowded and crowded dentitions were of 0.39 and 0.51 mm for the excess of anterior and total upper tooth mass, respectively, with respect to lower mass excess. Although the anterior and overall ratios and the differences between the upper and lower tooth width sums are greater in subjects with crowding, no clinically significant difference is observed (less than one mm).