Predictive factors of sagittal stability after treatment of Class II malocclusions

Objective:To determine the existence of factors permitting the prediction of sagittal stability after orthodontic treatment in patients with Angle Class II malocclusion.Materials and Methods:PubMed, EMBASE, and the Cochrane Library were searched up to March 2015. Inclusion criteria were longitudinal studies with at least 10 subjects investigating associations between at least one factor and stability, with an average minimum follow-up period of 2 years; stability measured using posttreatment sagittal dental changes; and orthodontic treatment including removable and/or fixed appliances with or without extractions. Two reviewers independently selected and assessed the quality of the articles.Results:The search strategy resulted in 1372 articles, of which 17 met the inclusion criteria. Large changes during treatment in molar and canine relationships were the only two factors found to be positively associated with relapse, but with limited evidence. Fourteen factors were found not to be predictive of relapse, also with limited evidence. These factors included treatment characteristics, patient pretreatment characteristics, and final posttreatment characteristics.Conclusions:There is currently limited evidence to support the influence of factors predictive of sagittal stability following Class II malocclusion treatment. More high-quality prospective studies are needed, and functional factors possibly affecting relapse also need to be further assessed.     

An evaluation of the use of digital study models in orthodontic diagnosis and treatment planning

The purpose of the present study was to determine the diagnostic and treatment planning value of digital models when compared with plaster study casts. In addition, the level of orthodontic experience of the examiner was assessed to determine whether this would have an influence on the decision-making process. Thirty randomly selected orthodontic patients from the Department of Orthodontics at the University of Alabama were selected for the study. From the 30 record sets, seven were selected attempting to mirror cases required for presentation to the American Board of Orthodontics. The seven evaluators were divided into two groups on the basis of their level of orthodontic experience. Initially, each evaluator assessed each patient record. Each evaluator was given a standardized questionnaire which recorded the evaluator's diagnosis based on use of the digital study models (T1). Regardless of whether the evaluator requested a review of the plaster study casts, the evaluator was given the plaster study casts. The evaluator then, using the plaster casts, filled out another identical questionnaire (T2). A chi-square test was used to determine any group differences in the frequency of changed diagnostic characteristics, treatment mechanical procedures, or proposed treatment plans after evaluating plaster study models. The statistical significance selected was P = .05 level of significance. The results showed that 12.8% of diagnostic characteristics, 12% of treatment mechanic procedures, and 6% of proposed treatment plans changed after T2. The results of the present study indicate that in the vast majority of situations digital models can be successfully used for orthodontic records.     

Evaluation of the use of digital study models in postgraduate orthodontic programs in the United States and Canada

Objective:To investigate the extent, experience, and trends associated with digital model use, as well as the advantages of using a particular study model type (digital or plaster) in postgraduate orthodontic programs in the United States and Canada.Materials and Methods:An electronic survey consisting of 14 questions was sent to 72 program directors or chairpersons of accredited orthodontic postgraduate programs in the United States and Canada.Results:Fifty-one responded for a 71% response rate. Sixty-five percent of the schools use plaster study models compared with 35% that use digital models. The most common advantages of plaster models were a three-dimensional feel and the ability for them to be mounted on an articulator. The most common advantages of digital models were the ease of storage and retrieval, and the residents'' exposure to new technology. About one third of the plaster model users reported that they wanted to switch to digital models in the future, with 12% planning to do so within 1 year.Conclusions:Based on our study, 35% of accredited orthodontic postgraduate programs in the United States and Canada are using digital study models in most cases treated in their programs, and the trend is for increased digital model use in the future.     

Modifications in Class I and Class II Div. 1 malocclusion during orthodontic treatment and their association with TMD problems

ABSTRACT

Objective: To observe changes in tooth movements of patients with Class I and Class II malocclusion during the first 6 months of orthodontic treatment and to investigate the relation between TMJ problems and these changes.

Methods: The sample was comprised of 63 individuals (20 control, 25 Class I malocclusion, 18 Class II Div. 1 malocclusion). Occlusion analysis was performed through T-Scan® record and chewing pattern examination before and after the 6-month period. The existence of TMD was evaluated using joint vibration analysis (JVA). Patients with malocclusion had active fixed orthodontic treatment.

Results: Disclusion time reduced in the patients group during the treatment period. No association was observed between the first 6-month period of the orthodontic treatment and TMD.

Discussion: It is suggested that occlusion analyses should be done before any orthodontic treatment, and disclusion time should be minimized as much as possible.     

Modern trends in Class III orthognathic treatment: A time series analysis

Objective:To examine the current trends in surgical-orthodontic treatment for patients with Class III malocclusion using time-series analysis.Materials and Methods:The records of 2994 consecutive patients who underwent orthognathic surgery from January 1, 2004, through December 31, 2015, at Seoul National University Dental Hospital, Seoul, Korea, were reviewed. Clinical data from each surgical and orthodontic treatment record included patient''s sex, age at the time of surgery, malocclusion classification, type of orthognathic surgical procedure, place where the orthodontic treatment was performed, orthodontic treatment modality, and time elapsed for pre- and postoperative orthodontic treatment.Results:Out of the orthognathic surgery patients, 86% had Class III malocclusion. Among them, two-jaw surgeries have become by far the most common orthognathic surgical treatment these days. The age at the time of surgery and the number of new patients had seasonal variations, which demonstrated opposing patterns. There was neither positive nor negative correlation between pre- and postoperative orthodontic treatment time. Elapsed orthodontic treatment time for both before and after Class III orthognathic surgeries has been decreasing over the years.Conclusion:Results of the time series analysis might provide clinicians with some insights into current surgical and orthodontic management.     

Malocclusion and orthodontic treatment need evaluated among subjects with Down syndrome using the Dental Aesthetic Index (DAI)

Objective:To determine the prevalence of malocclusion and need for orthodontic treatment among persons with Down Syndrome (DS).Materials and Methods:Study participants were 113 persons with DS from the selected community-based rehabilitation center who fulfilled the inclusion and exclusion criteria. Ten occlusal characteristics of the Dental Aesthetic Index (DAI) were measured on study models to determine the degree of malocclusion. A single score represented the dentofacial anomalies, determined the level of severity, and determined the need for orthodontic treatment.Results:Crowding in the anterior maxillary and mandibular arch was the main malocclusion problems among the subjects with DS. Comparison between age group and genders revealed no significant differences in four categories of orthodontic treatment need (P > .05).Conclusion:Most of the subjects with DS (94; 83.2%) had severe and very severe malocclusion, which indicated a desirable and mandatory need for orthodontic treatment.     

Prevalence of malocclusion among children of the Kingdom of Saudi Arabia – A systematic review and meta-analysis

ObjectiveSystematic review and meta-analysis are of a great tool in assessment of malocclusion, which is major public health concern. This study aims to explore the prevalence of malocclusion among the children of the Kingdom of Saudi Arabia through a meta-analysis and systematic review.Materials and methodsRegistered with PROSPERO as CRD42020198427, an authentic and global scale database search using relevant MeSH (Medical Subject Headings) terms was performed. Literature search and articles screening done following PRISMA guidelines.For the dichotomous variables, 95% confidence intervals (CIs) were set for statistical data analysis. The heterogeneity index between the studies was determined using indices Tau², Chi², df and I² and Test for overall effect as Z.ResultsA total of 7930 candidates were reported to have either one of the three malocclusions. Prevalence of Class I, Class II and Class III Malocclusions were found to be 66.51%, 17.70%, 15.79% respectively. Among the small subsample of these candidates, male children with Class I, Class II and Class III Malocclusion were 43.80%, 12.27% and 7.40% respectively whereas female children were 22.07%, 10.93 %, 3.52 % respectively.ConclusionsAccording to the 26 studies included in the systematic review, there were 72% of the candidates with malocclusion in Saudi Arabia. Prevalence of Class I, Class II and Class III malocclusion were 66.51%, 17.70%, and 15.79% respectively. In both male and female participants, the prevalence of Class I was the highest followed by class II and III malocclusion.     

Influence of lateral cephalometric radiography in orthodontic diagnosis and treatment planning

Objective:To evaluate the impact of additional lateral cephalometric radiography in orthodontic diagnosis and treatment planning.Materials and Methods:Forty-three patients seeking orthodontic treatment, and for whom pretreatment diagnostic records were available, were randomly selected. Ten qualified orthodontists were involved in this study. The patients'' records included three photographs of the angle trimmed dental casts, digital lateral cephalometric and panoramic radiographs, and standard clinical photographs comprising seven intra- and four extraoral pictures. Records were evaluated in two sessions. At the first session, orthodontists evaluated records without lateral cephalometric radiography (LCR). In the second session, the same information was presented, but with LCR. Between the two sessions the order in which the cases were presented was altered to avoid bias.Results:The percentage of agreement between sessions was lower for diagnosis than for treatment planning. Concerning skeletal classification, the least experienced orthodontist was the least consistent (28%), while the more experienced orthodontist was the more reliable (67%). In terms of treatment modalities, in general there was an agreement of 64%. The most frequent modifications in treatment modalities were seen in Class II malocclusion patients.Conclusions:The results of our study suggest that the majority of Portuguese orthodontists judge that LCR is important to producing a treatment plan. Despite that, it does not seem to have an influence on orthodontic treatment planning.     

Prevalence of malocclusion among children of the Kingdom of Saudi Arabia – A systematic review and meta-analysis

ObjectiveSystematic review and meta-analysis are of a great tool in assessment of malocclusion, which is major public health concern. This study aims to explore the prevalence of malocclusion among the children of the Kingdom of Saudi Arabia through a meta-analysis and systematic review.Materials and methodsRegistered with PROSPERO as CRD42020198427, an authentic and global scale database search using relevant MeSH (Medical Subject Headings) terms was performed. Literature search and articles screening done following PRISMA guidelines.For the dichotomous variables, 95% confidence intervals (CIs) were set for statistical data analysis. The heterogeneity index between the studies was determined using indices Tau², Chi², df and I² and Test for overall effect as Z.ResultsA total of 7930 candidates were reported to have either one of the three malocclusions. Prevalence of Class I, Class II and Class III Malocclusions were found to be 66.51%, 17.70%, 15.79% respectively. Among the small subsample of these candidates, male children with Class I, Class II and Class III Malocclusion were 43.80%, 12.27% and 7.40% respectively whereas female children were 22.07%, 10.93 %, 3.52 % respectively.ConclusionsAccording to the 26 studies included in the systematic review, there were 72% of the candidates with malocclusion in Saudi Arabia. Prevalence of Class I, Class II and Class III malocclusion were 66.51%, 17.70%, and 15.79% respectively. In both male and female participants, the prevalence of Class I was the highest followed by class II and III malocclusion.     

The influence of text messages on the cooperation of Class II patients regarding the use of intermaxillary elastics

Objectives:To evaluate the influence of text messages on cooperation of Class II patients with the use of intermaxillary elastics.Materials and Methods:The sample consisted of 42 orthodontic patients (20 males and 22 females) aged between 14 and 34 years. They were randomly divided into one of the following two groups: a control group with 21 patients who did not receive messages and an experimental group with 21 patients who received motivational and reminder text messages. Messages were sent twice a week for a period of 3 months. The patients were instructed to wear the elastics all day, removing them only during meals and replacing them daily. All patients were instructed regarding the importance of cooperation. Measurements were performed with a digital caliper on plaster models at the beginning of elastics wear (T1) and 3 months later (T2). For intragroup and intergroup comparisons between T1 and T2, paired and unpaired t-tests, respectively, were used with a significance level of 5%.Results:Statistically significant differences were observed in the intra- and intergroup comparisons between T1 and T2. Both groups showed a decrease in the sagittal distance between upper and lower arches from T1 to T2, demonstrating the effective use of elastics. However, the experimental group showed a Class II correction that was 3.7 times greater than the control group (P = .001).Conclusions:Text messages had a positive influence on the cooperation of patients regarding the use of intermaxillary elastics in the orthodontic treatment of Class II malocclusion.     

British Orthodontic Society,UTG session abstracts

Abstract

The popularity and availability of virtual technology in orthodontics for the replacement of hard-copy records with electronic records is growing rapidly, with a move towards a ‘digital’ patient for diagnosis, treatment planning, monitoring of treatment progress and outcome. As part of this ongoing development, three-dimensional digital models of the dental arches have the potential to replace traditional plaster models and their associated limitations for treatment planning, appliance construction and simulated treatment outcomes. This article provides the reader with a summary of the currently available benchtop model scanners and intraoral scanners. It is likely that this technology will become increasingly common-place within the orthodontic profession over the next decade.     

Root resorption in relation to a modified piezocision technique

ObjectivesTo evaluate root resorption of lower incisors and canines quantitatively in a group of patients who underwent orthodontic treatment with piezocision and/or a collagen reinforcement technique with a fully resorbable three-dimensional (3D) collagen xenograft matrix compared with a control group.Materials and MethodsThe study sample of this secondary analysis consisted of 32 periodontally healthy patients with angle Class I malocclusion or mild Class II or III malocclusion and moderate irregularity index scores who underwent orthodontic treatment and had before (T0) and after treatment (T1) cone-beam computed tomography scans. Root resorption of lower incisors and canines was assessed quantitatively in the following four groups: the control group received orthodontic treatment without piezocision, experimental group 1 received orthodontic treatment with piezocision, experimental group 2 received orthodontic treatment with piezocision and a 3D collagen matrix, and experimental group 3 received orthodontic treatment with a 3D collagen matrix.ResultsAn overall statistically significant decrease in root length from T0 to T1 for all groups was observed (P < .05). However, there was no significant difference among the groups in the amount of root length decrease from T0 to T1.ConclusionsOrthodontic treatment combined with piezocision does not increase the risk of root resorption of lower incisors and canines when compared with orthodontic treatment without acceleration techniques. More studies with larger samples should be undertaken to confirm these results.     

Digital images as an alternative to orthodontic casts in assessing malocclusion and orthodontic treatment need

Objective. To investigate the potential use of two-dimensional digital images as an alternative to orthodontic casts in the assessment of malocclusion and orthodoantic treatment need. Material and Methods. Assessment of malocclusion (Angle's classification of molars, overjet, and overbite) and orthodontic treatment need (Index of Orthodontic Treatment Need (IOTN): Dental Health Component (DHC) and Aesthetic Component (AC)) was conducted on 313 study casts and their images by two trained and calibrated examiners. Agreement of orthodontic treatment need and Angle's molar classification was assessed employing Kappa statistics (κ). Agreement of overjet and overbite (measured in mm) was assessed in comparison and correlation analyses. Inter- and intra-examiner reliability of assessment was investigated. Results. There was substantial agreement of the molar relationship classifications (κ >0.70), orthodontic treatment need as assessed by IOTN-DHC (κ =0.79) and IOTN-AC (κ =0.56) between measurements obtained from orthodontic casts and their images. There was also substantial agreement of measurements of overjet and overbite as obtained from orthodontic casts and their images. The standardized directional differences of overjet and overbite were ≤0.2. The intra-class correlation coefficients of assessments of overjet and overbite obtained from orthodontic casts and their images were >0.90. Inter- and intra-examiner reliability for the assessment of malocclusion and orthodontic treatment need was acceptable. Conclusion. Two-dimensional digital images can be used as an alternative to casts in assessment of malocclusion and orthodontic treatment need.     

Predicted versus executed surgical orthognathic treatment

ObjectivesThis study aimed to analyse combined surgical-orthodontic treatment plans, compare them with the actual surgery performed, and define factors resulting in changes of the original plan during orthodontic pre-surgical preparation.Study designThe clinical files of 312 orthognathic surgery patients, operated between January 2008 and December 2010, were retrospectively reviewed. Of these 312 patients, 129 had a bimaxillary operation. One hundred sixty patients had osteotomy of the lower jaw only and 23 had osteotomy of the upper jaw only. Factors analysed in the study include Angle Class malocclusion, patient sex, and age. Lip-to-incisor relationship, overjet, overbite and midline deviations of the upper and lower jaw were recorded. Effects of surgical assisted rapid palatal expansion (SARPE) on the eventual surgery were also investigated. Reasons for changing the original treatment plan at the time of the finished pre-surgical-orthodontic alignment were analysed.ResultsThe original treatment plan was changed in 42 of the 312 patients (13.5%). Changes occurred generally in case of a larger interval between set-up of the first treatment plan and the eventual operation (average 22.4 versus 16.4 months for patients with changed versus unchanged treatment plan, respectively). All Class I patients had surgery performed as planned. Class III patients had a significantly higher rate of altered treatment plan (27.3%) than Class II patients (7.6%). More men (52.4%) saw their treatment plan changed, although there were more women than men in the study population (59.6 versus 40.4%).ConclusionOne in seven patients (13.5%) had a different operation than was planned at the start of treatment. Class III patients with small overjet and overbite commonly have a treatment plan for a monomaxillary operation that, after decompensation, needs to be adapted to a bimaxillary operation.     

An evaluation of self-esteem and quality of life in orthodontic patients: Effects of crowding and protrusion

Objective:To evaluate the effect of dental crowding and lip protrusion on self-esteem and quality of life (QOL) in female orthodontic patients with Class I malocclusion.Materials and Methods:The study sample consisted of 201 patients (mean age 22.6 ± 3.0 years) who sought orthodontic treatment. All the patients were evaluated before treatment in terms of their degree of dental crowding and lip protrusion. Rosenberg''s Self-Esteem Scale and the Orthognathic Quality of Life Questionnaire (OQLQ) were used to determine self-esteem and QOL and to evaluate whether these values were related to malocclusion severity.Results:The results indicated that severe crowding and severe protrusion can result in lower self-esteem and poorer QOL (P < .05) than mild crowding and protrusion in Class I malocclusion. In the oral function component of the OQLQ, the severity of protrusion did not have significant effect.Conclusions:In Class I malocclusion, patients with mild crowding or protrusion had significantly better self-esteem and QOL scores than severe crowding or protrusion patients.     

Treatment effects of fixed functional appliances alone or in combination with multibracket appliances: A systematic review and meta-analysis

Objective:To assess skeletal and dentoalveolar effects of fixed functional appliances, alone or in combination with multibracket appliances (comprehensive treatment), on Class II malocclusion in pubertal and postpubertal patients.Materials and Methods:Literature survey was conducted using the Medline, SCOPUS, LILACS, and SciELO databases and The Cochrane Library, and through a manual search. The studies retrieved had to have a matched untreated control group. No restrictions were set regarding the type of fixed appliance, treatment length, or to the cephalometric analysis used. Data extraction was mostly predefined at the protocol stage by two authors. Supplementary mandibular elongation was used for the meta-analysis.Results:Twelve articles qualified for the final analysis of which eight articles were on pubertal patients and four were on postpubertal patients. Overall supplementary total mandibular elongations as mean (95% confidence interval) were 1.95 mm (1.47 to 2.44) and 2.22 mm (1.63 to 2.82) among pubertal patients and −1.73 mm (−2.60 to −0.86) and 0.44 mm (−0.78 to 1.66) among postpubertal patients, for the functional and comprehensive treatments, respectively. For pubertal subjects, maxillary growth restraint was also reported. Nevertheless, skeletal effects alone would not account for the whole Class II correction even in pubertal subjects with dentoalveolar effects always present.Conclusions:Fixed functional treatment is effective in treating Class II malocclusion with skeletal effects when performed during the pubertal growth phase, very few data are available on postpubertal patients.     

Rapid maxillary expansion effects in Class II malocclusion: A systematic review

Objective:To evaluate the effectiveness of rapid maxillary expansion (RME) on the sagittal dental or skeletal parameters of growing children with Class II malocclusion.Materials and Methods:A systematic review intended to identify relevant literature was conducted. The search was performed on Medline, Embase, Cochrane Library, and Scopus databases. Reference lists of the included articles were also screened for relevant documents. The qualitative assessment was performed according to the Methodological Index for Non-Randomized Studies (MINORS) tool, and the resultant data were grouped and analyzed concerning dental and skeletal sagittal effects of RME.Results:Of 25 screened studies, seven articles met eligibility criteria and were included. Study samples were observed during mixed dentition stage and characterized as having either Class II dental malocclusion or skeletal discrepancy. None of the included studies was a randomized clinical trial. Included controlled studies presented several inadequacies related to control group or lacked appropriate comparative statistical analysis. Besides being frequently based on deficient methodology, dental and skeletal sagittal effects of RME were either controversial or lacked clinical relevance.Conclusion:The effect of RME on the sagittal dimension of Class II malocclusions has not been proved yet. Future randomized controlled clinical trials are still needed to definitely address this question.     

Intra‐arch dimensional measurement validity of laser‐scanned digital dental models compared with the original plaster models: a systematic review

A systematic review was undertaken to evaluate the validity of intra‐arch dimensional measurements made from laser‐scanned digital dental models in comparison with measurements directly obtained from the original plaster casts (gold standard). Finally included articles were only those reporting studies that compared measurements from digital models produced from laser scanning against their plaster models. Measurements from the original plaster models should have been made using a manual or digital caliper (gold standard). Articles that used scans from impressions or digital photographs were discarded. Detailed individual search strategies for Cochrane, EMBASE, MEDLINE, PubMed, and LILACS were developed. The references cited in the selected articles were also checked for any references that could have been missed in the electronic database searches. A partial gray literature search was undertaken using Google Scholar. The methodology of selected studies was evaluated using the 14‐item quality assessment tool for diagnostic accuracy studies (QUADAS). Only 16 studies were finally included for the qualitative/quantitative synthesis. The selected studies consistently agree that the validity of measurements obtained after using a laser scanner from plaster models is similar to direct measurements. Any stated differences would be unlikely clinically relevant. There is consistent scientific evidence to support the validity of measurements from digital dental models in comparison with intra‐arch dimensional measurements directly obtained from them.     

Linear measurements using virtual study models: A systematic review

Objective:To perform a systematic review of the literature to assess the reliability and validity of linear measurements using virtual vs plaster study models.Materials and Methods:A search strategy was developed for four online databases, and references were further hand searched for studies additional papers. Three researchers determined the eligibility of papers by applying specific selection criteria and ultimately selected 17 papers. Grouped by virtual model acquisition type and the number of landmarks used in a given measurement, the data were weighted by sample size and analyzed in terms of the reliability and validity of linear measurements.Results:The intrarater reliability was high for two-landmark and >two-landmark linear measurements performed on laser-acquired models or cone-beam computed tomography (CBCT)–acquired models and were similar to measurements on plaster models. Validity was high for two-landmark and >two-landmark linear measurements comparing laser-acquired models or CBCT-acquired models to plaster study models, and the weighted mean differences were clinically insignificant. Agreement of measurements was excellent, with less variability than correlation. Acquisition type had no perceived influences on reliability and validity. More than two-landmark measures tended to have higher mean differences than two-landmark measures.Conclusions:Virtual study models are clinically acceptable compared with plaster study models with regard to intrarater reliability and validity of selected linear measurements.     

Characterization of phenotypes of skeletal Class III malocclusion in Korean adult patients treated with orthognathic surgery using cluster analysis

ObjectivesTo characterize the phenotypes of skeletal Class III malocclusion in adult patients who underwent orthognathic surgery (OGS).Materials and MethodsThe sample consisted of 326 patients with Class III malocclusion treated with OGS (170 men and 156 women; mean age, 22.2 years). Using lateral cephalograms taken at initial visits, 13 angular variables and one ratio cephalometric variable were measured. Using three representative variables obtained from principal components analysis (SNA, SNB, and Björk sum), K-means cluster analysis was performed to classify the phenotypes. Statistical analysis was conducted to characterize the differences in the cephalometric variables among the clusters.ResultsClass III phenotypes were classified into nine clusters from the following four major groups: (1) retrusive maxilla group, clusters 7 and 9 (7.1% and 5.5%; severely retrusive maxilla, normal mandible, severe and moderate hyperdivergent, respectively) and cluster 6 (9.2%; retrusive maxilla, normal mandible, normodivergent); (2) relatively protrusive mandible group, cluster 2 (20.9%; normal maxilla, normal mandible, hyperdivergent); (3) protrusive mandible group, clusters 3 and 1 (11.7% and 15.3%; normal maxilla, protrusive mandible, normodivergent and hyperdivergent, respectively) and clusters 8 and 4 (15.3% and 3.7%; normal maxilla, severe protrusive mandible, normodivergent and hypodivergent, respectively); and (4) protrusive maxilla and protrusive mandible group, cluster 5 (11.4%; protrusive maxilla, severely protrusive mandible, normodivergent). Considerations for presurgical orthodontic treatment and OGS planning were proposed based on the Class III phenotypes.ConclusionsBecause the anteroposterior position of the maxilla and rotation of the mandible by a patient''s vertical pattern determine Class III phenotypes, these variables should be considered in diagnosis and treatment planning for patients who have skeletal Class III malocclusion.