Malocclusion In Adolescents Research Articles

Psycho-social impact of malocclusion in adolescents in Kosovo.

To assess the psychosocial impact of malocclusion, establish its association with the severity of malocclusion and determine the effects of gender and age in such association. Cross-sectional study. 400 adolescents aged between 12-15 years were randomly selected. Each participant was examined for malocclusion and categorized according to Index of Orthodontic Treatment Need (IOTN) and Dental Aesthetic Index (DAI). The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) was used to assess the psychosocial impact of malocclusion. Significant differences were noted between PIDAQ subscales, and grades of malocclusion assessed by IOTN and DAI (p⟨0.05). Gender differences were noted in Dental Self Confidence (DSC), Social Impact (SI) and Psychological Impact (PI) for the same severity of malocclusion (p⟨0.05). IOTN-DHC predicted the total and subscales of PIDAQ scores. Gender and age were the independent predictive variables of the relationship between the PIDAQ scores and the IOTN-DHC grades for the DSC and AC subscales. Gender independently predicted psychological impact. Severity of malocclusion, gender and age were related to impacts on the psychosocial wellbeing of participants. Overall, females and older participants experienced worse psychosocial impact.

Dental and skeletal effects after total arch distalization using modified C-palatal plate on hypo- and hyperdivergent Class II malocclusions in adolescents.

To compare the dental and skeletal treatment effects after total arch distalization using modified C-palatal plates (MCPPs) on adolescent patients with hypo- and hyperdivergent Class II malocclusion. The study group included 40 patients with Class II malocclusion (18 boys and 22 girls, mean age = 12.2 ± 1.4 years) treated with MCPPs. Fixed orthodontic treatment started with the distalizing process in both groups. Participants were divided into hypo- or hyperdivergent groups based on their pretreatment Frankfort mandibular plane angle (FMA) ≤22° or ≥28°, respectively. Pre- and posttreatment lateral cephalograms were digitized, and 23 variables were measured and compared for both groups using paired and independent t-tests. The hyper- and hypodivergent groups showed 2.7 mm and 4.3 mm of first molar crown distalizing movement, respectively (P < .001). The hypodivergent group had a slight 2.2° crown distal tipping of first molars compared with 0.3° in the hyperdivergent group. After distalization, the FMA increased 3.1° and 0.3°, in the hypodivergent and hyperdivergent groups, respectively (P < .001). SNA decreased in the hypodivergent group, while other skeletal variables presented no statistically significant differences in the changes between the groups. The hypodivergent group showed more distal and tipping movement of the maxillary first molar and increased FMA than the hyperdivergent group. Therefore, clinicians must consider vertical facial types when distalizing molars using MCPPs in Class II nonextraction treatment.

Dental and skeletal effects after total arch distalization using modified C-palatal plate on hypo- and hyperdivergent Class II malocclusions in adolescents.

To compare the dental and skeletal treatment effects after total arch distalization using modified C-palatal plates (MCPPs) on adolescent patients with hypo- and hyperdivergent Class II malocclusion. The study group included 40 patients with Class II malocclusion (18 boys and 22 girls, mean age = 12.2 ± 1.4 years) treated with MCPPs. Fixed orthodontic treatment started with the distalizing process in both groups. Participants were divided into hypo- or hyperdivergent groups based on their pretreatment Frankfort mandibular plane angle (FMA) ≤22° or ≥28°, respectively. Pre- and posttreatment lateral cephalograms were digitized, and 23 variables were measured and compared for both groups using paired and independent t-tests. The hyper- and hypodivergent groups showed 2.7 mm and 4.3 mm of first molar crown distalizing movement, respectively (P < .001). The hypodivergent group had a slight 2.2° crown distal tipping of first molars compared with 0.3° in the hyperdivergent group. After distalization, the FMA increased 3.1° and 0.3°, in the hypodivergent and hyperdivergent groups, respectively (P < .001). SNA decreased in the hypodivergent group, while other skeletal variables presented no statistically significant differences in the changes between the groups. The hypodivergent group showed more distal and tipping movement of the maxillary first molar and increased FMA than the hyperdivergent group. Therefore, clinicians must consider vertical facial types when distalizing molars using MCPPs in Class II nonextraction treatment.

Assessment of Treatment Duration in Orthodontic Retraction for Class I and Class II Malocclusion in Adolescents

Assessment of Treatment Duration in Orthodontic Retraction for Class I and Class II Malocclusion in Adolescents

How is orthodontic treatment need associated with perceived esthetic impact of malocclusion in adolescents?

The purpose of this research was to evaluate the esthetic impact of orthodontic treatment need in adolescents. This cross-sectional study was performed with 1172 adolescents aged 12 (n=638) years and 15 (n=534) years from Salvador, Bahia, Brazil. The esthetic impact was the following outcome variables: Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale. The normative orthodontic treatment need was assessed by the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) and by the Dental Aesthetic Index (DAI). Logistic regression models were adjusted, estimating crude odds ratio with the respective 95% confidence intervals. The variables with P≤0.20 in the individual analyses were tested in multiple logistic regression models, remaining the variables with P≤0.05. The results showed a statistically significant association for the esthetic impact (Aesthetic Component of the Index of Orthodontic Treatment Need and the Oral Aesthetic Subjective Impact Scale) when assessing the normative orthodontic treatment need by the DAI (P<0.05). However, there was no significant association between subjective esthetic impact and normative needs when using the IOTN-DHC (P>0.05). DAI was more associated with the adolescents' esthetic concern than IOTN-DHC and should be the Index of Orthodontic Treatment Need to be selected to complement the patient's self-perception.

Factors related to the psychological impact of malocclusion in adolescents

To study the association between orthodontic treatment need and the psychosocial impact of dental aesthetics in a sample of adolescents, as well as other associated factors. A transversal study was conducted on 1,158 adolescents (12–16 years old) examined at the schools selected for the 2018 epidemiological study on oral health in the Comunidad Valenciana (Spain). The need for orthodontic treatment was determined by DAI and IOTN. The psychosocial impact was established by the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). Other variables considered were sex, social class, DMFT index and Body-Mass Index, and having previously worn or presently wearing an orthodontic device. A lineal regression statistical technique was applied to study the significant associations with the scoring obtained in PIDAQ. The PIDAQ scores revealed a significant and positive lineal relationship with regard to need for orthodontic treatment: DAI (ẞ = 0.20) and IOTN-DHC (ẞ = 4.87), in women (ẞ = 2.66) and a negative one for having previously worn an orthodontic device (ẞ = − 5.74). The rest of the variables had no statistical significance (p > 0.05). The psychosocial impact of dental aesthetics in adolescents is associated with the presence of malocclusion and the female sex, while the condition of having previously worn an orthodontic device reduces the psychosocial impact.

Outcome assessment of orthodontic clear aligner vs fixed appliance treatment in a teenage population with mild malocclusions.

To assess the efficacy and efficiency of treatment in adolescents presenting with mild malocclusions, comparing outcomes using clear aligners to fixed appliances. Patients identified retrospectively and consecutively from one private practice had been treated with either clear aligners (Invisalign, Align Technology, Santa Clara, Calif) or fixed appliances (0.022 Damon, Ormco, Orange, Calif; n = 26/group). Assessments of occlusion were made using the American Board of Orthodontics Discrepancy Index (DI) for initial records and Cast-Radiograph Evaluation (CRE) for final records. Number of appointments, number of emergency visits, and overall treatment time were determined from chart reviews. Data were analyzed using Pearson's correlation, Wilcoxon rank tests, unpaired t-tests, and Chi-square tests, with significance set to P ≤ .05. Pretreatment, the aligner and fixed groups showed no significant difference in overall severity (DI: 11.9 ± 5.3 vs 11.6 ± 4.8) or in any individual DI category. Posttreatment scores showed finishes for the aligner group had fewer discrepancies from ideal relative to the fixed appliance group (CRE: 30.1 ± 8.3 vs 37.0 ± 9.3; P < .01). Patients treated with aligners had fewer appointments (13.7 ± 4.4 vs 19.3 ± 3.6; P < .0001), fewer emergency visits (0.8 ± 1.0 vs 3.6 ± 2.5; P < .0001), and shorter overall treatment time (16.9 ± 5.7 vs 23.4 ± 4.4 months; P < .0001). Outcomes for treatment of mild malocclusions in adolescents showed equivalent effectiveness of clear aligners compared to fixed appliances, with significantly improved results for clear aligner treatment in terms of tooth alignment, occlusal relations, and overjet. Assessment of the number of appointments, number of emergency visits, and overall treatment time showed better outcomes for treatment with clear aligners.

Meta-analysis of the efficacy of bone anchorage and maxillary facemask protraction devices in treating skeletal class Ⅲ malocclusion in adolescents

To assess the efficacy of bone anchorage and maxillary facemask protraction devices in treating skeletal class Ⅲ malocclusion in adolescents. Articles relating to the use of bone anchorage and maxillary facemask protraction devices for treating skeletal class Ⅲ malocclusion in adolescents were searched from the databases of Cochrane Library, PubMed, EmBase, CNKI, and Wanfang database. Several inclusion and exclusion criteria were developed for the article screening. The clinical data were extracted, and the quality of the selected articles was evaluated. A Meta-analysis of SNA, SNB, ANB, ANS-Me, Wits, and U1-PP change was performed by using RevMan 5.3. Seven studies (264 patients) were included in the Meta-analysis. Among these studies, three were randomized controlled trials, and four were non-randomized controlled trials. Compared with the maxillary facemask protraction device group, the bone ancho-rage device group had higher SNA changes and lower ANS-Me, Wits, and U1-PP changes (P<0.05). No significant differences were observed in the SNB and ANB changes between these two groups. Compared with the maxillary facemask protraction device, the bone anchorage device can increase the extent of protraction of the maxilla and has better controls for the labial inclination of the maxillary anterior teeth in treating skeletal class Ⅲ malocclusion among adolescents. However, additional high-quality randomized controlled trials must be performed to verify the results.

Influencing factors of functional orthopedic appliances on skeletal class Ⅱ malocclusion in adolescents

Influencing factors of functional orthopedic appliances on skeletal class Ⅱ malocclusion in adolescents

Treatment effects of the Carriere® Motion 3D™ appliance for the correction of Class II malocclusion in adolescents.

To determine the treatment effects produced in Class II patients by the Carriere® Motion 3D™ appliance (CMA) followed by full fixed appliances (FFA). This retrospective study evaluated 34 adolescents at three time points: T1 (pretreatment), T2 (removal of CMA), and T3 (posttreatment). The comparison group comprised 22 untreated Class II subjects analyzed at T1 and T3. Serial cephalograms were traced and digitized, and 12 skeletal and 6 dentoalveolar measures were compared. Phase I with CMA lasted 5.2 ± 2.8 months; phase II with FFA lasted 13.0 ± 4.2 months. CMA treatment restricted the forward movement of the maxilla at point A. There was minimal effect on the sagittal position of the chin at pogonion. The Wits appraisal improved toward Class I by 2.1 mm during the CMA phase but not during FFA. Lower anterior facial height increased twice as much in the treatment group as in controls. A clockwise rotation (3.9°) of the functional occlusal plane in the treatment group occurred during phase I; a substantial rebound (-3.6°) occurred during phase II. Overjet and overbite improved during treatment, as did molar relationship; the lower incisors proclined (4.2°). The CMA appliance is an efficient and effective way of correcting Class II malocclusion. The changes were mainly dentoalveolar in nature, but some skeletal changes also occurred, particularly in the sagittal position of the maxilla and in the vertical dimension.

CBCT evaluation of condylar changes in children with unilateral posterior crossbites and a functional shift

Posterior crossbite is one of the most frequently occurring malocclusions in adolescents with a prevalence of 7% to 23%. The most common form of posterior crossbite is a unilateral posterior crossbite with a functional side shift. It has been suggested that functional posterior crossbites (FUPXB) may result in right-to-left-side differences in the condyle fossa relationship, resulting in temporomandibular joint (TMJ) problems. The objective of this study was to determine if pathological position of the condyles can cause condylar signs or symptoms like degenerative joint disease (DJD) or juvenile condylar resorption (JCR), or if the position of the condyle is just an altered position within the TMJ. Sixty patients with an average age of 9.6years were randomly selected from the office of one of the investigators (T.S.). The study group consisted of 29 patients with a FUPXB and the control group had 31 patients with no posterior crossbite. All patients had multislice CT scans of the TMJ taken as part of the orthodontic records. Transverse widths were measured at the skeletal base and the dentoalveolar base. Molar inclinations, condylar angulations, condylar anterior joint space, superior joint space, and posterior joint space were measured. Independent sample t-tests were used to compare different measurements between groups and paired sample t-tests were used to compare differences within the same patient. Reliability of measurements were determined using pairwise correlation. For dentoalveolar measurements of transverse width, the maxillomandibular difference for the study group was -8.2 mm and for the control group was -4.0 mm. No significant differences were found between the molar inclinations, condylar width, angulation, or any joint space measurements between the two groups. A total of 61.3% of the subjects in the control group and 72.4% in the study group had a radiographic sign of joint disease. The lack of condylar positional differences between the control and crossbite groups suggests that TMJ signs and symptoms in the study group may be related to remodeling in the TMJ instead.

Malocclusion and social vulnerability: a representative study with adolescents from Belo Horizonte, Brazil.

Malocclusion is public health problem because of its high prevalence, treatment possibility, and impact on the individual's quality of life. This article aims to determining the prevalence of malocclusion in adolescents and to test its association with social vulnerability. A representative transversal study was performed with 1612 adolescents aged between 11 and 14 years old who came from public and private schools in Belo Horizonte, Brazil. The adolescents were examined by three calibrated examiners for diagnosis of malocclusion, using the Dental Aesthetic Index. The Social Vulnerability Index from Belo Horizonte was used to determine the degree of social vulnerability from adolescents. The data were analyzed using Poisson regression with robust variance (p<0,05). Most adolescents presented absence/minor malocclusion (68.7%). Dental crowding was diagnosed in 51.9% from the sample, diastema in 23.7%, anterior open bite in 7.6 %. Malocclusion was associated with social vulnerability (PR=1.25;95% CI=1.01-1.55). Dental crowding was the most prevalent type of malocclusion. The more socially vulnerable adolescents had worse indicators of malocclusion.

Early-life socioeconomic status and malocclusion in adolescents and young adults in Uruguay.

This study aims to estimate orthodontic treatment need among 15-24 year-old individuals in Montevideo, Uruguay, and the association of occlusal traits with demographic, clinical and socioeconomic factors, considering a life course approach. A cross-sectional study using data from the First National Oral Health Survey in Uruguay was conducted. A two-stage cluster procedure was used to select a sample of 278 individuals in Montevideo. Household interviews and oral examinations were performed by six dentists. Dental Aesthetic (DAI) and Decayed Missing and Filled Teeth Indices (DMFT) were used to assess orthodontic treatment need and dental caries, respectively. Early life and current socioeconomic factors were obtained from the interview. Ordinal logistic regression was used to model the DAI index. Prevalence of definite malocclusion was 20.6%, followed by severe (8.2%) and very severe (7.6%). In the adjusted analysis, individuals with untreated dental caries (OR = 1.11; 95%CI: 1.03-1.20) and those who reported a lower socioeconomic level at 6 years of age (OR = 5.52; 95%CI: 1.06-28.62) had a higher chance of being a worse case of malocclusion. Current socioeconomic position was not associated with orthodontic treatment need. Individuals aged 22-24 years (OR = 1.59; 95%CI: 1.05-2.41) had a lower chance than those aged 14-17. This study shows that orthodontic treatment need is relatively high in Uruguayan adolescents and young adults. There is a potential relationship between early life socioeconomic status and the occurrence of malocclusion in adolescents and young adults under a life course approach.

Completely-customized lingual orthodontics to correct class II malocclusion in adolescents

Completely-customized lingual orthodontics is an efficient, predictable and esthetic solution for our patients. Adolescents showing a class II malocclusion represent the majority of patients in orthodontic practices. Several modes of treatment are available to correct this sagittal discrepancy such as inter-maxillary elastics, flexible or rigid protrusion devices, maxillary distalization using mini-screws or symmetric and asymmetric extractions. The choice depends on several decision criteria such as the severity of the malocclusion, the symmetry of the class II discrepancy as well as the age and the motivation of the patient. In this article, the authors will describe the current therapeutical strategies to correct a class II malocclusion in adolescents with a completely-customized lingual appliance. It is as easy to correct a significant class II malocclusion with a lingual technique as it is with vestibular techniques, completely-customized lingual orthodontics providing the advantage of facilitating treatments.

Relationship between the mandibular hypoplasia and temporomandibular joint internal derangement in adolescents with skeletal class Ⅱ malocclusion

Mandibular hypoplasia is very common clinically. Studies have reported that temporomandibular joint internal derangement (TMJID) might manifest as mandibular retrusion, and whether there is a direct correlation between them remains controversial in academia. On the other hand, for adolescent patients with skeletal class Ⅱ malocclusion, the growth of mandible could be motivated by orthopedic force, and then the mandibular retrusion corrected. However, if TMJID is the direct cause of mandibular retrusion, orthopedic treatment will not have a significant effect on it. Base on literature review and analysis as well as our own research, this article will review the distribution of structural abnormalities of the temporomandibular joint in adolescents with mandibular hypoplasia and its association with skeletal class Ⅱ malocclusion, as well as the effect of TMJID on the treatment of skeletal class Ⅱ malocclusion in adolescents.

Severity of malocclusion in adolescents: populational-based study in the north of Minas Gerais, Brazil

ABSTRACTOBJECTIVE To identify the factors associated with severity of malocclusion in a population of adolescents.METHODS In this cross-sectional population-based study, the sample size (n = 761) was calculated considering a prevalence of malocclusion of 50.0%, with a 95% confidence level and a 5.0% precision level. The study adopted correction for the effect of delineation (deff = 2), and a 20.0% increase to offset losses and refusals. Multistage probability cluster sampling was adopted. Trained and calibrated professionals performed the intraoral examinations and interviews in households. The dependent variable (severity of malocclusion) was assessed using the Dental Aesthetic Index (DAI). The independent variables were grouped into five blocks: demographic characteristics, socioeconomic condition, use of dental services, health-related behavior and oral health subjective conditions. The ordinal logistic regression model was used to identify the factors associated with severity of malocclusion.RESULTS We interviewed and examined 736 adolescents (91.5% response rate), 69.9% of whom showed no abnormalities or slight malocclusion. Defined malocclusion was observed in 17.8% of the adolescents, being severe or very severe in 12.6%, with pressing or essential need of orthodontic treatment. The probabilities of greater severity of malocclusion were higher among adolescents who self-reported as black, indigenous, pardo or yellow, with lower per capita income, having harmful oral habits, negative perception of their appearance and perception of social relationship affected by oral health.CONCLUSIONS Severe or very severe malocclusion was more prevalent among socially disadvantaged adolescents, with reported harmful habits and perception of compromised esthetics and social relationships. Given that malocclusion can interfere with the self-esteem of adolescents, it is essential to improve public policy for the inclusion of orthodontic treatment among health care provided to this segment of the population, particularly among those of lower socioeconomic status.

Maternal breastfeeding, parafunctional oral habits and malocclusion in adolescents: A multivariate analysis

ObjectiveMalocclusion may result in esthetic impairment and functional disorders such as bad chewing, speech and swallowing, with a negative impact on quality of life. There is uncertainty regarding the effects of breastfeeding on dentofacial malocclusions. The purpose of the study was to evaluate the relationship between maternal breastfeeding and dental malocclusions and facial characteristics in adolescents with permanent dentition. MethodsProbabilistic sampling of 2060 12- to 15-year-old students in a cross-sectional study was used. Malocclusion, as defined by Angle, and facial characteristics were the dependent variables. The duration of breastfeeding was the main independent variable. Other covariates were tested as effect modifiers or confounders. The associations were estimated using the odds ratio (OR) in multinomial logistic regression analysis (α=5%). ResultsThere was an association between a short duration of breastfeeding (less than 6 months) and Angle class II (OR=3.14; 95% CI: 1.28–7.66) and class III (OR=2.78; 95% CI: 1.21–6.36) malocclusion only in students with a prolonged history of bruxism. A higher occurrence of severe convex profile (OR=3.4; 95% CI: 0.63–18.26) and a lower occurrence of cancave profile (OR=0.43; 95% CI: 0.21–0.88) were also observed only among adolescents who had been breastfed for a short period and exposed to a long periods of mouth breathing. ConclusionsThese findings support the hypothesis that breastfeeding alone seems not to be directly associated with malocclusions, but it may have a synergetic effect with parafunctional oral habits on the development of occlusofacial problems. It is recommended that deleterious oral habits be avoided, especially by children who were breast-fed for less than 6 months.

Effect of anterior teeth display during smiling on the self-perceived impacts of malocclusion in adolescents

To investigate the impact of the anterior teeth display during smiling (ATDDS) on the self-perceived psychosocial impacts of malocclusion in adolescents. This cross-sectional study included a convenience sample of 301 adolescents (mean age 16.1 years, SD 1.8 years; 58.1% female). Two instruments were used for data collection: (1) the Dental Aesthetic Index (DAI) and (2) the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). In addition, ATDDS was assessed in posing smiling, and adolescents' satisfaction with their dental appearance was investigated. Data analysis included descriptive statistics, Kruskal-Wallis test and Mann-Whitney U-test, Spearman correlation, and multiple linear regression analysis. Significant associations were observed between independent variables (ATDDS, DAI scores, and satisfaction with dental appearance) and total PIDAQ score (R(2) = 0.37) and dental self-confidence (R(2) = 0.37), psychological impact (R(2) = 0.30), esthetic concern (R(2) = 0.20), and social impact (R(2) = 0.15). The excessive anterior teeth display during smiling may potentially influence the self-perceived psychosocial impacts of malocclusion in adolescents depending on the severity level of malocclusion and the self-reported satisfaction with dental appearance.

Associação entre presença de oclusopatias e insatisfação com a aparência dos dentes e gengivas: estudo com adolescentes brasileiros

In spite of the high prevalence of malocclusion in adolescents reported worldwide, there are few studies that have investigated the association between normative malocclusion and self-rated dental and gingival appearance among adolescents. The aim of this study was to identify the association between normative malocclusion and dissatisfaction with dental and gingival appearance among Brazilian adolescents. A cross-sectional study was carried out with adolescents aged 15 to 19 years (n= 16,126) living in 250 towns of all five Brazilian regions. Dissatisfaction with dental and gingival appearance was the outcome. The main explanatory variable was malocclusion assessed by using the Dental Aesthetic Index - DAI. The other explanatory variables included were per capita family income, schooling delay, study conditions, sex, age, skin color, dental outcomes (untreated dental caries, missing teeth due dental caries, dental calculus, fluorosis, and dental pain) and use of dental services. Simple and multivariable Poisson regression analyses were performed. Dissatisfaction with dental appearance reached 11.4% (95%CI: 10.4-12.5) of the entire sample. All levels of malocclusion were associated with dissatisfaction with dental appearance. Adjusted multivariable analysis showed that dissatisfaction with dental appearance among individuals affected by severe or very severe malocclusion was respectively 40% and 80% higher than among those with normal occlusion. Malocclusion was associated with dissatisfaction with dental and gingival appearance. The results contribute to include self-rated dental appearance criteria in orthodontic treatment decision, mainly within the National Health System - SUS.

Editor's Comment and Q&A: Comparison of Twin-block and Dynamax appliances for the treatment of Class II malocclusion in adolescents: A randomized controlled trial

Introduction The aim of this study was to compare the effectiveness of Twin-block and Dynamax appliances for the treatment of Class II Division 1 malocclusion. Methods This was a randomized controlled trial involving 32 boys and 32 girls aged 10 to 14 years with Class II Division 1 malocclusion. They were randomly allocated to either the Dynamax appliance group or the Twin-block appliance group. Treatment was provided by 4 clinicians at 2 centers. Records were taken at the start and the end of the functional phase and after all treatment. In addition, incisal overjet, the number of appliance breakages, and adverse events or side effects of the treatment were recorded at each patient visit. Results The data monitoring committee in an interim analysis at 18 months after the start of the trial found significantly greater overjet reduction in the Twin-block group than in the Dynamax group and more breakages and adverse events with the Dynamax appliance. As a result, treatment with the Dynamax appliance was terminated, and those patients completed treatment with the Twin-block or a fixed appliance. Regression analysis showed a statistically significant difference in the performance over time between the Twin-block and Dynamax appliances in terms of reduction in overjet, with the Twin-block appliance performing significantly better than the Dynamax. The incidence of adverse events was greater in the Dynamax group (82%) than in the Twin-block group (16%), with a statistically significant difference (P Conclusions The Twin-block appliance was more effective than the Dynamax appliance when overjet was evaluated and the Dynamax appliance patients reported greater incidence of adverse events with their appliance than those who were treated with the Twin-block appliance.