Effect of early treatment on stability of occlusion in patients with Class II malocclusion

Elastodontic Appliances for the Interception of Malocclusion in Children: A Systematic Narrative Hybrid Review

BACKGROUND

Interceptive orthodontic treatment aims to eliminate factors that prevent the harmonious development of the maxillary and mandibular arches during childhood, and elastodontic appliances (EAs) represent a group of devices with an increasingly important role. This systematic narrative hybrid review (HR) aims to provide an overview of the clinical indications for the use of EAs according to the available evidence and to identify potential research areas for unexplored applications.

MATERIALS AND METHODS

To assess the available literature on the subject, selective database searches were performed between July 2023 and September 2023. With the assistance of a health sciences librarian, a search strategy that utilized terms related to elastodontic therapy was developed. Embase, Scopus, PubMed, and Web of Science were the databases used.

RESULTS

The current literature addressing the usability of EAs is scarce and mostly limited to case reports and case series. After 2168 citations were found through the searches, 13 studies were ultimately included. In this regard, information about the clinical use and effectiveness of EAs are reported in a narrative form, defining specific domains of the application that are clinically oriented, including sagittal and transversal discrepancies, atypical swallowing, teeth malposition, two-phase orthodontics and a lack of teeth retention.

CONCLUSIONS

Within the intrinsic quality limitation of the available literature, it seems that EAs may represent a promising treatment alternative for managing mild-to-moderate malocclusion in children as an adjuvant therapy to the interruption of spoiled habits.

Palatal changes after treatment of functional posterior cross-bite using elastodontic appliances: a 3D imaging study using deviation analysis and surface-to-surface matching technique

BACKGROUND

The present study aimed to evaluate the changes in palate dimension and morphology after treatment of functional posterior crossbite (FPXB) with elastodontic devices (EAs).

METHODS

The treatment group (TG) consisted of 25 subjects (mean age 7.3 ± 0.9 years) who received treatment with EA for one year. The control group (CG) comprised 14 untreated subjects (mean age 6.8 ± 0.7 years).

INCLUSION CRITERIA

intra-oral scan registered before (T0) and after treatment (T1), FPXB with a mandibular shift towards the crossbite site of ≥ 2 mm, class I molar relationship.

EXCLUSION CRITERIA

missing teeth, anterior crossbite, temporomandibular disorders, previous orthodontic treatment, carious lesions, mobility of deciduous posterior teeth, craniofacial deformities. Digital models were analyzed to assess the inter-canine (ICW) and inter-molar widths (IMW) and the corresponding emi-lateral measurements (eICW and eIMW) using the median palatine plane as reference. According to a specific 3D imaging technology, the morphology and symmetry of the palate was investigated by analysing the 3D deviation between the two specular models of the palate.

RESULTS

At T0, both groups showed a significantly narrower dimension of eICW and eIMW at the crossbite side compared to the non-crossbite side (p < 0.05). Also, the 3D deviation analysis demonstrates a limited matching percentage of the original/mirrored models in both TG (81.12%) and CG (79.36%), confirming the asymmetry of the palate. The area of mis-matching was located at the alveolar bone level. At T1, subjects in the TG showed a significant increment of ICW and IMW (p < 0.05), a reduction of the differences of eICW and eIMW between both sides (p < 0.05) and an increment of the percentage matching (TG = 92.32%) (p < 0.05), suggesting a significant recovery of the palatal asymmetry. No significant changes were found between T0 and T1 in the CG (p > 0.05).

CONCLUSIONS

EAs could be successfully used to correct FPXB in mixed dentition and could restore the harmonious development of the palate in children.

Validity and Reproducibility of the Peer Assessment Rating Index Scored on Digital Models Using a Software Compared with Traditional Manual Scoring

The aim of this study was to assess the validity and reproducibility of digital scoring of the Peer Assessment Rating (PAR) index and its components using a software, compared with conventional manual scoring on printed model equivalents. The PAR index was scored on 15 cases at pre- and post-treatment stages by two operators using two methods: first, digitally, on direct digital models using Ortho Analyzer software; and second, manually, on printed model equivalents using a digital caliper. All measurements were repeated at a one-week interval. Paired sample t-tests were used to compare PAR scores and its components between both methods and raters. Intra-class correlation coefficients (ICC) were used to compute intra- and inter-rater reproducibility. The error of the method was calculated. The agreement between both methods was analyzed using Bland-Altman plots. There were no significant differences in the mean PAR scores between both methods and both raters. ICC for intra- and inter-rater reproducibility was excellent (≥0.95). All error-of-the-method values were smaller than the associated minimum standard deviation. Bland-Altman plots confirmed the validity of the measurements. PAR scoring on digital models showed excellent validity and reproducibility compared with manual scoring on printed model equivalents by means of a digital caliper.

New Materials for Orthodontic Interceptive Treatment in Primary to Late Mixed Dentition. A Retrospective Study Using Elastodontic Devices

The aim of this study was to assess the skeletal and dentoalveolar changes obtained after 1 year of treatment with elastodontic appliances (EA) in a retrospective cohort of children reporting early signs of malocclusion. Also, a detailed description of the tested EAs was reported. The study sample included 20 subjects, 8 males and 12 females, with a mean age of 8.4 ± 0.6 years, and a control group consisting of 20 subjects, 9 males and 11 females, with a mean age of 8.1 ± 0.8 years. All subjects in the treated group received the AMCOP second class (SC) (Ortho Protec, Bari, Italy) device. Digital impressions were taken along with a digital bite registration in centric relation before treatment (T0) and after 1 year (T1). Lateral cephalograms were also taken at T0 and T1 and cephalometric analysis was performed to assess the skeletal sagittal changes of the maxilla and the mandible (sella, nasion, A point angle, SNA^; sella, nasion, B point angle, SNB^; and A point-nasion-B point angle, ANB^) as well as the changes of the inter-incisors angle (IIA^). In the treated group, the distribution of subjects according to the presence of crowding and the pattern of malocclusion changed at T1. In the same group, there was an increase of subjects showing no signs of crowding and a class I occlusal relationship, while in the control group, there was a small increase of subjects developing dental crowding and featuring a worse sagittal relationship (class II) compared to pre-treatment condition. A statistically significant reduction of the overjet and overbite was recorded in the treated group between T0 and T1 (p < 0.05); in the control group, a slight increase in the overjet and overbite was detected at T1, being this increment significanct only for the latter parameter. In the tested group, no significant differences were found between SNA^ values detected at T0 and T1 (p > 0.05), instead the SNB^, ANB^, and IIA^ showed a significant increase after 1 year of treatment (p < 0.05). From a clinical perspective, all clinical goals were reached since patients showed remarkable improvements in overjet, overbite, crowding, and the sagittal molar relationship. Within the limitations of the present study, EAs could be effectively used for the interceptive orthodontic in growing patients.

Effectiveness of lingual versus labial fixed appliances in adults according to the Peer Assessment Rating index

INTRODUCTION

The purpose of this study was to compare the effectiveness of lingual treatment and labial fixed appliances in the treatment of adult orthodontic patients.

METHODS

We conducted a retrospective study of 72 patients. The Peer Assessment Rating (PAR) index was measured at the start (T0) and end (T1) of treatment. Significant differences between treatment means were determined by means of analysis of variancewith the Bonferroni correction or with the use of Fisher exact test.

RESULTS

The lingual group had a mean pretreatment age of 28.6 ± 6.7 years, and the labial group had a pretreatment age of 26.6 ± 9.5 years. This difference was statistically not significant. The mean pre- and posttreatment PAR scores in the labial group were 22.9 ± 6.2 and 2.1 ± 2.3, respectively, and the mean pre- and posttreatment PAR scores in the lingual group were 26.5 ± 8.3 and 2.3 ± 2.5. There were no significant differences between the treatment groups.

CONCLUSIONS

Lingual and labial appliances produced similar reductions in PAR scores. There was no difference in the posttreatment PAR scores between the lingual and labial treatment groups. Further studies involving larger sample sizes and longer follow-up periods are required to confirm the results obtained.

Comparison of early treatment outcomes rendered in three different types of malocclusions

Objective:

To evaluate the outcome of early treatment in Class I, II, and III malocclusions based on the reduction of weighted Peer Assessment Rating (PAR) scores.

Materials and Methods:

Two hundred thirty subjects (female = 105; male = 125) selected from 400 cases were divided into three groups based on their malocclusions (Class I, II, and III). The PAR index was evaluated prior to early treatment (T0), at the end of phase I (T1), and after completion of phase II therapy (T2). The reliability of overall PAR scores was assessed by Bland-Altman plot and intraclass correlation coefficient. The starting age, total weighted PAR scores and their changes after phase I and II treatments, treatment time, and the percentage of correction in the three different malocclusions were assessed by repeated-measures analysis of variance with post hoc analysis. The level of significance was set at P &lt; .05.

Results:

More than 30% reduction of the weighted PAR scores and less than 10 points of the remaining weighted PAR scores were observed in all malocclusion groups at T1. The Class III group had the highest percentage of correction during phase I treatment.

Conclusions:

Early treatment effectively reduced the complexity of Class I, II, and III malocclusions and accounted for 57%, 64%, and 76% of the total correction, respectively, after phase I treatment, as indicated by an overall reduction in weighted PAR scores. The Class III group responded most favorably to early treatment followed by the Class II group.

Perception, knowledge and attitudes of Brazilian orthodontists on the treatment of Class II malocclusions

The present study aimed to assess the perception and knowledge of Brazilian orthodontists on the ideal moment to treat Class II malocclusions. Questionnaires with open, semi-open and close questions were sent by e-mail to 1653 Brazilian orthodontists. These orthodontists were registered in the Brazilian Association of Orthodontics and Dentofacial Orthopedics (ABOR). One-hundred and three (9.86%) Orthodontists replied to the questionnaires. Most of them were males (60.5%) with specialization as the highest level of professional qualification (59.9%). Most of the orthodontists (51%) reported preference for treating Class II malocclusions in late mixed dentition, followed by the early mixed dentition (29%). The age range between 10 and 12 years old figured as the most prevalent in patients searching for treatment (42.7%). Most of the patients searching for treatment were females (69.7%). Preferences for functional orthopedic appliances were reported by 35% of the orthodontists. Brazilian orthodontists revealed a trend for treating patients with Class II malocclusions in the late mixed dentition. Female patients aged from 10 to 12 years old represented the majority of patients that search for orthodontic treatment. Functional orthopedic appliances were preferred by Brazilian orthodontists for treating Class II malocclusions.

Orthodontic treatment stability predictors: A retrospective longitudinal study

OBJECTIVE

To examine medium- to long-term orthodontic treatment stability and its possible association with certain variables.

MATERIALS AND METHODS

In a retrospective longitudinal study of 70 postretention patients, the Peer Assessment Rating (PAR) index was measured at the start (T1) and end (T2) of treatment and between 4 and 10 years afterwards (T3). The stability was considered absolute when the T2 and T3 values were identical and relative when the difference was within the ±5 range.

RESULTS

Among the 70 patients, 65.8% were female and 34.2% were male. Their mean age was 14.5 years. The mean treatment length was 2.4 years. The mean retention phase was 3.3 years. The mean pre- and posttreatment PAR scores were 29.8 (T1) and 6.3 (T2). The mean T1-T2 difference was 23.6. The mean T2-T3 difference was -0.39.

CONCLUSIONS

Within the study, 7.1% presented absolute stability and 68.6% presented relative stability. Lower anterior segment alignment and overbite were the most unstable occlusal features and tended to worsen. Fixed retainer (odds ratio [OR] 0.31; 95% confidence interval [CI] 0.10-0.98) as a protective factor and years without retention (OR 1.32; 95% CI 1.03-1.68) as a risk factor are predictor variables of instability in the case of lower anterior segment alignment. The PAR value at the end of treatment (OR 1.29; 95% CI 1.08-1.54) and extractions (OR 4.76; 95% CI 1.05-21.6) before treatment are predictors for midline instability.

Selecting subjects with high craniofacial shape homogeneity for clinical trials

INTRODUCTION

Morphologic homogeneity is desirable in sample selection of clinical studies that evaluate methods of treating craniofacial discrepancies in orthodontics. The purposes of this study were to assess sample selection criteria commonly used in the orthodontic literature regarding their effectiveness in achieving morphologic homogeneity, and to propose a method that can guarantee selection of a homogeneous sample, for which the degree of homogeneity and the average skeletal pattern can be specified a priori.

METHODS

Pretreatment lateral cephalograms from 170 consecutive patients (82 boys, 88 girls) aged 7 to 17 years were used. Sixteen skeletal and 4 dental landmarks were digitized and processed with Procrustes superimposition and principal component analysis. The sample was bootstrapped to a virtual population of 10,000 subjects by random sampling from the normal distribution for each principal component. A systematic literature search of randomized controlled trials showed that the most prevalent sample selection criteria, in addition to molar relationship, included overjet, ANB, and SN-GoGn. Each criterion was applied to the virtual population. The morphologic homogeneity of the samples was assessed as the percentage of shape variance of each sample relative to the shape variance of the population.

RESULTS

The first 3 principal components incorporated approximately 53% of shape variability. The evaluated criteria achieved low or moderate morphologic homogeneity scores (range, 28%-63%), and the selected patients were widely spread in the shape space. Although the criteria are commonly applied for selecting samples with skeletal discrepancies, a considerable number of subjects with an average shape were selected. The proposed procedure entails selecting a skeletal pattern appropriate for the study's purpose, setting limits in shape space within which the sample should be confined, and testing candidate patients against these limits. The patients within these boundaries have, by definition, a similar shape to the selected skeletal pattern and form a homogeneous sample.

CONCLUSIONS

The cephalometric variables that have been used in randomized controlled trials do not result in samples of high morphologic homogeneity. The proposed method guarantees high morphologic homogeneity. The extent of homogeneity, the average shape of the sample, and the sample's relationship to the general population's average can be specified a priori.

Intrarater agreement about the etiology of Class II malocclusion and treatment approach

INTRODUCTION

The management of patients with Class II malocclusion has been an ongoing discussion in orthodontics. The aim of this study was to determine whether orthodontists agree among themselves and with each other about the etiology, timing, and difficulty of treating subjects with Class II malocclusion.

METHODS

The initial records of 159 Class II subjects were sent to 8 orthodontists. In this sample, duplicate records of 18 subjects were dispersed. A questionnaire was sent with the records.

RESULTS

The intrarater consistency values were 65% when determining the type of malocclusion, 60% when deciding which arch was at fault, and 81% when determining the need for immediate treatment. Consistency values were 33% regarding case difficulty and 77% regarding phase 2 treatment need. There was a significant negative correlation between the consistency of the orthodontists' responses and the peer assessment rating score.

CONCLUSIONS

We found that practitioners had only moderate agreement among themselves when diagnosing a patient's type of malocclusion and which arch was at fault when a skeletal discrepancy was noted. Intrarater agreement improved as the peer assessment rating score increased, but the correlation was weak, and this was not consistent for all examiners. Because of insufficient intrarater agreement, interrater agreement was not examined.