Expert consensus on pediatric orthodontic therapies of malocclusions in children

Malocclusion, identified by the World Health Organization (WHO) as one of three major oral diseases, profoundly impacts the dental-maxillofacial functions, facial esthetics, and long-term development of ~260 million children in China. Beyond its physical manifestations, malocclusion also significantly influences the psycho-social well-being of these children. Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition, by mitigating the negative impact of abnormal environmental influences on the growth. Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development, ranging from fetal stages to the early permanent dentition phase. From an economic and societal standpoint, the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated, underlining its profound practical and social importance. This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children, emphasizing critical need for early treatment. It elaborates on corresponding core principles and fundamental approaches in early orthodontics, proposing comprehensive guidance for preventive and interceptive orthodontic treatment, serving as a reference for clinicians engaged in early orthodontic treatment.

Long-term effects of orthodontic interceptive expansion treatment : A retrospective study

PURPOSE

The aim of this retrospective cohort study was to evaluate the long-term effects of interceptive orthodontic treatment with a removable expansion plate, based on transversal, sagittal, and vertical parameters.

METHODS

A total of 90 patients needing interceptive treatment due to a crossbite or space deficiency were included. Records consisting of clinical photos, radiographs, and digital dental casts were collected for evaluation at two time points: the start of interceptive treatment (T0) and the start of comprehensive treatment (T1). Molar occlusion, overjet, overbite, presence and type of crossbite, mandibular shift, and transversal measurements were recorded for comparison.

RESULTS

After expansion with removable appliances, a significant increase in intermolar width was achieved and could be maintained over the observation period (p < 0.001). However, no significant changes regarding overjet, overbite, or molar sagittal occlusion were observed. Crossbite correction was successful in 86.9% of patients with unilateral crossbite and in 75.0% of patients with bilateral crossbite (p < 0.001).

CONCLUSION

Early expansion with a removable expansion plate is a successful method to correct crossbites and increase intermolar width in the early mixed dentition phase. Results remain stable until the start of comprehensive treatment in the permanent dentition.

Early orthodontic treatment in a Finnish public health centre: a retrospective cross-sectional study

OBJECTIVES

The aim of this observational cross-sectional one-centre study was to assess whether the previously described national orthodontic treatment practises and international recommendations are implemented in a public health care centre in Finland. We also assessed early treatment practices and appliances used.

METHODS

The study group comprised 801 children born in 2011 and 2012 residing in the Riihimäki health centre catchment area in Finland, representing 80% of the age cohort. The patient records were examined for data on orthodontic treatment, timing of treatment, appliances used, and occlusal traits.

RESULTS

The children had been examined by four orthodontist specialists and two orthodontic postgraduate students. Mean age at occlusal examination had been 9 years. Of the children, 212 (26%) were undergoing or had undergone orthodontic treatment. An additional 4.4% were scheduled for treatment. The proportion of children deemed to need treatment was significantly different between the different orthodontists. The most frequently used appliances were quad-helix (30%), eruption guidance appliance (20%), head gear (14%), fixed appliances (10%), protraction facemask (10%), and passive mandibular lingual arch (6%).

CONCLUSIONS

Nearly one-third of children aged less than 12 years in the health centre were currently or had been in orthodontic treatment. Approximately half had received treatment with either quad-helix or eruption guidance appliance.

Three-dimensional assessment of palatal area changes after posterior crossbite correction with tooth-borne and tooth bone-borne rapid maxillary expansion

OBJECTIVES

To assess and compare the three-dimensional treatment changes in palatal surface area and volume using either tooth-borne (TB) or tooth bone-borne (TBB) rapid maxillary expanders and to evaluate the long-term effects of the two devices and the incidence of the relapse between the groups.

MATERIALS AND METHODS

A total of 52 consecutive patients who met the eligibility criteria were recruited and allocated to either the TB group, mean age 9.3 years (standard deviation [SD], 1.3), or the TBB group, mean age 9.5 years (SD, 1.2). Study casts were taken before, directly after, 1 year after, and 5 years after expansion. Study casts were digitized, superimposed, and evaluated. Participants were randomly allocated in blocks of different sizes using the concealed allocation principle in a 1:1 ratio.

RESULTS

Changes in palatal volume, palatal surface area, and palatal projection area within and between the groups up to 5 years after expansion followed the same pattern and did not show any statistically significant differences between the groups. Relapse was seen in 15% of the patients. It seemed that open-bite and a Class III growth pattern could be assumed as prognosis-deteriorating factors in regard to stability of the treatment.

CONCLUSIONS

There were no significant differences between the TB and TBB groups in palatal volume, palatal shell area, or palatal projection area directly after expansion or at 1 year and 5 years after expansion, which implies that the two devices gave rise to the same immediate and long-term outcomes.

The effectiveness of the early orthodontic correction of functional unilateral posterior crossbite in the mixed dentition period: a systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to critically appraise the available evidence of the effectiveness of early intervention of functional unilateral posterior crossbites (FPXB) between the ages of 6 and 12 years.

Materials and methods

Electronic search in four databases (PubMed, Scopus, Embase, and Google Scholar) for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) was performed between 1^st January 1990 and 31^st October 2021. Methodological index for non-randomized studies (MINORS) for CCTs and Cochrane's risk of bias tool for RCTs were applied. The certainty of the evidence was evaluated according to the grading of recommendations, assessment, development, and evaluation (GRADE) approach.

Results

Nine studies (6 RCTs and 3 CCTs) were included in this review, and six of them were appropriate for quantitative synthesis. The meta-analysis revealed that the quad-helix (QH) was more effective than expansion plates (EP) in increasing the intermolar width (WMD = 1.25; 95% CI 0.75, 1.75; P < 0.001), and decreasing treatment time (WMD = − 3.36; 95% CI − 4.97, − 1.75; P < 0.001). The relapse rate at 5.6 years post-treatment was greater in the QH group than in the EP group (RR = 3.00); however, the difference was statistically insignificant. There was no significant difference between the QH and the EP in other outcome measures. When assessing the rapid maxillary expansion (RME), only one RCT compared the RME with an untreated control group and reported a significant increase in the maxillary intermolar and intercanine width (P < 0.001, P = 0.002, respectively) and a significant decrease in lower midline deviation (P < 0.001).

Conclusion

There is weak to moderate evidence that the treatment of functional posterior crossbite (FPXB) by the QH increased the maxillary intermolar width and the success rate and decreased the treatment duration compared to the EP. The relapse percentage was greater in the QH group. There is very weak evidence that the mandibular midline correction rate did not differ significantly between the QH and the EP modalities. The RME using the Hyrax appliance corrected the FPXB successfully; however, the strength of evidence in this regard is very low. As the quality of evidence ranged from very low to moderate in this review, we confirm the need for more RCTs with different expansion appliances in the early treatment of FPXB.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40510-022-00398-4.

Orthodontic treatment for posterior crossbites

BACKGROUND

A posterior crossbite occurs when the top back teeth bite inside the bottom back teeth. The prevalence of posterior crossbite is around 4% and 17% of children and adolescents in Europe and America, respectively. Several treatments have been recommended to correct this problem, which is related to such dental issues as tooth attrition, abnormal development of the jaws, joint problems, and imbalanced facial appearance. Treatments involve expanding the upper jaw with an orthodontic appliance, which can be fixed (e.g. quad-helix) or removable (e.g. expansion plate). This is the third update of a Cochrane review first published in 2001.

OBJECTIVES

To assess the effects of different orthodontic treatments for posterior crossbites.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched four bibliographic databases up to 8 April 2021 and used additional search methods to identify published, unpublished and ongoing studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of orthodontic treatment for posterior crossbites in children and adults.

DATA COLLECTION AND ANALYSIS

Two review authors, independently and in duplicate, screened the results of the electronic searches, extracted data, and assessed the risk of bias of the included studies. A third review author participated to resolve disagreements. We used risk ratios (RR) and 95% confidence intervals (CIs) to summarise dichotomous data (event), unless there were zero values in trial arms, in which case we used odds ratios (ORs). We used mean differences (MD) with 95% CIs to summarise continuous data. We performed meta-analyses using fixed-effect models. We used the GRADE approach to assess the certainty of the evidence for the main outcomes.

MAIN RESULTS

We included 31 studies that randomised approximately 1410 participants. Eight studies were at low risk of bias, 15 were at high risk of bias, and eight were unclear. Intervention versus observation For children (age 7 to 11 years), quad-helix was beneficial for posterior crossbite correction compared to observation (OR 50.59, 95% CI 26.77 to 95.60; 3 studies, 149 participants; high-certainty evidence) and resulted in higher final inter-molar distances (MD 4.71 mm, 95% CI 4.31 to 5.10; 3 studies, 146 participants; moderate-certainty evidence). For children, expansion plates were also beneficial for posterior crossbite correction compared to observation (OR 25.26, 95% CI 13.08 to 48.77; 3 studies, 148 participants; high-certainty evidence) and resulted in higher final inter-molar distances (MD 3.30 mm, 95% CI 2.88 to 3.73; 3 studies, 145 participants, 3 studies; moderate-certainty evidence). In addition, expansion plates resulted in higher inter-canine distances (MD 2.59 mm, 95% CI 2.18 to 3.01; 3 studies, 145 participants; moderate-certainty evidence). The use of Hyrax is probably effective for correcting posterior crossbite compared to observation (OR 48.02, 95% CI 21.58 to 106.87; 93 participants, 3 studies; moderate-certainty evidence). Two of the studies focused on adolescents (age 12 to 16 years) and found that Hyrax increased the inter-molar distance compared with observation (MD 5.80, 95% CI 5.15 to 6.45; 2 studies, 72 participants; moderate-certainty evidence). Intervention A versus intervention B When comparing quad-helix with expansion plates in children, quad-helix was more effective for posterior crossbite correction (RR 1.29, 95% CI 1.13 to 1.46; 3 studies, 151 participants; moderate-certainty evidence), final inter-molar distance (MD 1.48 mm, 95% CI 0.91 mm to 2.04 mm; 3 studies, 151 participants; high-certainty evidence), inter-canine distance (0.59 mm higher (95% CI 0.09 mm  to 1.08 mm; 3 studies, 151 participants; low-certainty evidence) and length of treatment (MD -3.15 months, 95% CI -4.04 to -2.25; 3 studies, 148 participants; moderate-certainty evidence). There was no evidence of a difference between Hyrax and Haas for posterior crossbite correction (RR 1.05, 95% CI 0.94 to 1.18; 3 studies, 83 participants; moderate-certainty evidence) or inter-molar distance (MD -0.15 mm, 95% CI -0.86 mm to 0.56 mm; 2 studies of adolescents, 46 participants; moderate-certainty evidence). There was no evidence of a difference between Hyrax and tooth-bone-borne expansion for crossbite correction (RR 1.02, 95% CI 0.92 to 1.12; I² = 0%; 3 studies, 120 participants; low-certainty evidence) or inter-molar distance (MD -0.66 mm, 95% CI -1.36 mm to 0.04 mm; I² = 0%; 2 studies, 65 participants; low-certainty evidence).  There was no evidence of a difference between Hyrax with bone-borne expansion for posterior crossbite correction (RR 1.00, 95% CI 0.94 to 1.07; I² = 0%; 2 studies of adolescents, 81 participants; low-certainty evidence) or inter-molar distance (MD -0.14 mm, 95% CI -0.85 mm to 0.57 mm; I² = 0%; 2 studies, 81 participants; low-certainty evidence).  AUTHORS' CONCLUSIONS: For children in the early mixed dentition stage (age 7 to 11 years old), quad-helix and expansion plates are more beneficial than no treatment for correcting posterior crossbites. Expansion plates also increase the inter-canine distance. Quad-helix is more effective than expansion plates for correcting posterior crossbite and increasing inter-molar distance. Treatment duration is shorter with quad-helix than expansion plates. For adolescents in permanent dentition (age 12 to 16 years old), Hyrax and Haas are similar for posterior crossbite correction and increasing the inter-molar distance. The remaining evidence was insufficient to draw any robust conclusions for the efficacy of posterior crossbite correction.

Correlations Between Mandibular Asymmetries and Temporomandibular Disorders: A Systematic Review

Objective

This systematic review aimed to investigate the correlation between mandibular asymmetry and temporomandibular disorders (TMDs).

Materials and Methods

A systematic search of the published literature was performed in electronic databases such as PubMed (MEDLINE), Scopus, Web of Science, Cochrane, Google Scholar, Clinicaltrials.gov, and Saudi Digital Library. Gray literature was searched through System for Information on Grey Literature through OpenGrey. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was followed in the investigation. The focussed question according to PICO format was: "does the mandibular asymmetry contribute to temporomandibular disorders"? Eligibility criteria included clinical trials (CTs), observation studies, cross-sectional and cohort studies in English that investigated mandibular asymmetries and TMD among patients. Blind and duplicate study selection, data extraction, and risk of bias assessment were carried out.

Results

The initial search resulted in 1906 articles, of which 11 (8 CTs, 1 cross-sectional, 1 retrospective, and 1 observational) studies were selected for qualitative synthesis after fulfilling the eligibility criteria.

Conclusion

Most of the studies included in this review showed either very high risk or high risk of bias. Despite the low certainty of evidence, the current study indicated a likely relationship between mandibular asymmetries and TMDs.

Palatal vault morphometric analysis of the effects of two early orthodontic treatments in anterior open bite growing subjects: a controlled clinical study

Background

The purpose of this study was to evaluate the palatal morphological changes in Anterior Open Bite (AOB) pre-pubertal subjects treated with Rapid Maxillary Expansion and Bite-Block (RME/BB) or Quad Helix with crib (QH/C) when compared with a Control Group (CG) by using Geometric Morphometric Analysis (GMM).

Methods

AOB group (AOBG) included 30 subjects (20 females, 10 males, mean age 8.1 ± 0.8ys) with dentoskeletal AOB. AOBG was divided in two subgroups according to the treatment strategy: RME/BB group (RME/BBg) included 15 subjects (10 females, 5 males, QH/C group (QH/Cg) comprised 15 subjects (10 females, 5 males). The two subgroups were compared with a CG of 15 subjects (10 females, 5 males) matched for sex, age, vertical pattern, and observation period. Digital upper dental casts were collected before treatment (T1) and at the end of the active treatment (T2). Landmarks and semilandmarks were digitized on dental casts and GMM was applied. Procrustes analysis and principal component analysis (PCA) were performed.

Results

At T2, RME/BBg when compared with QH/Cg evidenced no statistically significant differences. Instead, RME/BBg showed an increased maxillary transverse dimension and a decreased palatal depth when compared with CG. The comparison QH/Cg vs. CG demonstrated a slight transversal maxillary expansion.

Conclusions

RME/BBg showed significant changes in the transversal and vertical dimensions with a clear maxillary expansion and a decrease of the palatal depth when compared with QH/Cg and CG. QH/Cg showed a significant slight maxillary expansion and no variation in vertical and sagittal planes when compared with CG.

Short term effects of interceptive expansion treatment: a prospective study

OBJECTIVES

This prospective cohort study investigated the short term effects of interceptive orthodontic treatment with a removable expansion plate, evaluating the changes in occlusion in all its dimensions: transversal, sagittal and vertical.

SUBJECTS AND METHODS

A total of 226 patients treated with a removable expansion plate (slow maxillary expansion, SME) by orthodontic residents at the Department of Orthodontics, University Hospitals Leuven, Belgium were included. The patients had a mean age of 8.5 years at the start of the treatment. The mean treatment time was 6.9 months. Transversal measurements (intercanine and intermolar width) and occlusal characteristics (molar occlusion, overjet, overbite and functional shift) were collected before (T0) and after active treatment (T1). Statistical analysis was performed using the Wilcoxon signed rank test, Sign test and McNemar test for assessing changes between T0 and T1. Linear models were used to assess the associations between patient factors and the amount of expansion.

RESULTS

A significant increase in transversal width at different occlusal landmarks was found. Correction of unilateral, bilateral and frontal crossbites was successful in 99.0%, 95.2% and 93.6% of the cases respectively. Changes in sagittal molar occlusion were significant: 64.9% (right side) and 62.6% (left side) remained stable, 28.4% (right) and 29.3% (left) improved and 6.7% (right) and 8.1% (left) deteriorated. Overbite changes were found to be statistically significant, though clinically irrelevant. Overjet changes were non-significant.

CONCLUSIONS

A removable expansion plate is successful in improving the transversal dental dimensions of the maxilla. Statistically significant sagittal effects on molar occlusion were found. Long-term follow-up is needed to evaluate the long-term stability of this treatment.

Mandibular asymmetry in young adult patients with unilateral posterior crossbite: A controlled retrospective CBCT study

OBJECTIVE

This study aimed to evaluate the mandibular skeletal asymmetry in pre-orthodontic patients with the unilateral posterior dental crossbite (UPCB).

MATERIALS AND METHODS

Using a retrospective design, 30 pre-orthodontic patients with a UPCB, (16 on the right side, 14 on the left side), 18 females and 12 males were selected (mean age: 21.2±4.92 years), along with 30 controls matched by age and sex with cl I occlusal relationship (mean age: 21.9±4.80 years). The patients were from an Orthodontic Department of Dental Faculty of Hamadan University of Medical Sciences and a private office from 2009 to 2013. In the UPCB group, at least one molar tooth was in the crossbite position. All the patients had initial CBCT¹ and pre-orthodontic study models. 10 linear and 3 angular measurements were performed to evaluate the mandibular skeletal asymmetry. repeated measure-ANCOVA² by controlling the effect of age and sex, T-test and paired-samples t-test were used for comparisons. Measurement's reliability was measured with ICC³ test.

RESULTS

There was a positional deviation of mandible to the crossbite side 95% CI⁴ (0.166 - 1.087). The intergroup analysis showed that Corpus Length (P≤0.014), Ramus Angle in frontal view (P≤0.046), and Condylar-Width in axial view (P≤0.029) in the crossbite side of the case group were significantly smaller than the control group. In the subjects with UPCB, mandibular condylar width was smaller in the crossbite side (17.31±2.50) relative to the non-crossbite side (18.06±2.18).

CONCLUSIONS

The adults with dental UPCB, in addition to deviation to crossbite side, may show smaller condylar head and Corpus length in crossbite side relative to the control group.