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.

Changes in occlusion after orthognathic surgery: a systematic review and meta-analysis

PURPOSE

This study aims to systematically review and identify the changes of occlusion in patients after orthognathic surgery.

METHODS

The protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and was registered to the International Prospective Register of Systematic Reviews (PROSPERO) under the registration number CRD42021253129. Studies included were Original articles only, Additionally, studies were included if the outcome of occlusal force was measured pre- and postoperatively and if occlusal forces resulted from a long follow-up of a minimum of 1 year following orthognathic surgery using adequate measurement tools. Non-English articles, case reports, case series, and non-original articles, including systematic reviews and literature reviews, were excluded.

RESULTS

The search strategy yielded a total of 978 articles. Of the 978 articles, 285 were duplicates. After reading the titles and abstracts, 649 articles were excluded, and full-text articles of the remaining 47 studies were reviewed independently by two authors for eligibility wherein 33 articles were excluded, because they did not meet the inclusion criteria. Finally, a total of 14 studies were processed for critical review.

CONCLUSION

The occlusal force increased after orthognathic surgery, although not to the level of the control group; however, the maximal bite force remained unchanged. Immediately after orthognathic surgery, chewing and swallowing forces increased. Significant reductions in the postoperative occlusal contact pressure areas was also observed.

Relation Between Masticatory Performance and Skeletal Properties in Patients With Skeletal Class III Malocclusion

This study aimed to measure masticatory performance (MP) using β-carotene gummy jelly to investigate its relationship with skeletal properties in decompensated patients diagnosed with skeletal class III malocclusion. The study included 78 patients (38 men and 40 women) diagnosed with skeletal class III malocclusion without temporomandibular joint disorder and periodontal disease. MP was measured using a new masticatory measuring device and β-carotene in the gummy jelly. Lateral and posteroanterior cephalograms were obtained, and skeletal properties (Me deviation, ANB, SNB, APDI, Wits, ODI, facial axis, body length, ramus length, SN-GoGn, anterior facial height, posterior facial height, saddle angle, articular angle, and gonial angle) were evaluated. MP differences according to age and sex and the effect of skeletal properties on MP were analyzed using multiple linear regression analysis. The MP of all patients was 3690.55±1428.77 mm², MP of the male group was 4043.05±1498.09 mm², and MP of the female group was 3355.68±1272.19 mm². Among the items investigated, the variable that affected MP was posterior facial height. Posterior facial height showed a positive correlation (P=0.022). There was no significant difference between MP and other skeletal properties (P>0.05). The severity of the hypodivergency in skeletal class III could affect MP. The relationship between facial asymmetry or skeletal relation and MP could not be explained in this study.

Condylar Positional Changes in Skeletal Class II and Class III Malocclusions after Bimaxillary Orthognathic Surgery

Orthognathic surgery is indicated to modify the position of the maxillomandibular structure; changes in the mandibular position after osteotomy can be related to changes in the position of the mandibular condyle in the articular fossa. The aim of this study was to determine changes produced in the mandibular condyle 6 months after orthognathic surgery. A cross-sectional study was conducted that included subjects who had undergone bimaxillary orthognathic surgery to treat dentofacial deformity of Angle class II (group CII) or Angle class III (group CIII). Standardized images were taken using cone-beam computed tomography 21 days before surgery and 6 months after surgery; measurement scales were used to identify the condylar position and its relations with the anterior, superior, and posterior joint spaces. The results were analyzed using the Shapiro-Wilk and Student's t-tests, while considering a value of p < 0.05 as indicating a significant difference. Fifty-two joints from 26 patients, with an average age of 27.9 years (±10.81), were analyzed. All subjects in both group CII and group CIII showed a significant change in the anterior, superior, and posterior joint spaces. However, postoperative changes in the position of the condyle in the articular fossa were not significant in the anteroposterior analysis. We conclude that orthognathic surgery causes changes in the sagittal position of the mandibular condyle in subjects with mandibular retrognathism and prognathism.

Prevalence of signs and symptoms related to temporomandibular disorders and orofacial pain in patients indicated for orthognathic surgery: a meta-analysis

OBJECTIVE

To evaluate the prevalence of signs and symptoms related to temporomandibular disorders (TMD) and orofacial pain in patients with indication for orthognathic surgery.

METHODS

The search was carried out in seven electronic databases and gray literature. Studies that evaluated the frequency of signs and symptoms related to TMD and orofacial pain were included. The risk of bias was assessed using the Joanna Briggs Critical Appraisal tool. A meta-analysis of proportions with a random effect model was performed and the GRADE tool judged the certainty of evidence.

RESULTS

After searching the databases, 1859 references were retrieved, 18 of which were selected for synthesis. The prevalence of individuals with at least one TMD symptom was 51% [CI95% = 44-58%], and 44% of the subjects had temporomandibular joint click/crepitus [CI95% = 37-52%]. Additionally, 28% exhibited symptoms related to muscle disorders [CI95% = 22-35%], 34% had disc displacement with or without reduction [CI95% = 25-44%], and 24% had inflammatory joint disorders [CI95% = 13-36%]. The prevalence of headache was 26% [CI95% = 8-51%]. The certainty of evidence was considered very low.

CONCLUSION

Approximately 1 in 2 patients with dentofacial deformity presents some sign and symptom related to TMD. Myofascial pain and headache may be present in approximately a quarter of patients with dentofacial deformity.

CLINICAL RELEVANCE

A multidisciplinary treatment is necessary for these patients, involving a professional with expertise in the management of TMD.

The Impact of Orthodontic Treatment on Masticatory Performance: A Literature Review

The aim of this narrative review was to evaluate the possible association between orthodontic therapy and improved masticatory function. A search strategy was conducted using the PubMed database for up to January 2020 using the keywords "mastication" and "orthodontics". Only human studies investigating mastication in orthodontics settings were selected. The search strategy resulted in 1,011 articles, out of which 57 were included in the final analysis. Investigations have generally agreed that masticatory and chewing functions improved post-orthodontic and orthognathic treatments. Studies also showed improvement in the quality of life of patients' post-orthodontic treatment. The articles examined reinforced that besides esthetic reasons, orthodontic therapy does improve the masticatory and chewing functions of individuals, ultimately enhancing their health-related quality of life.

The consequences of living with a severe malocclusion: A review of the literature

AIM

To facilitate the orthognathic shared decision-making process by identifying and applying existing research evidence to establish the potential consequences of living with a severe malocclusion.

METHODS

A comprehensive narrative literature review was conducted to explore the potential complications of severe malocclusion. A systematic electronic literature search of four databases combined with supplementary hand searching identified 1024 articles of interest. A total of 799 articles were included in the narrative literature review, which was divided into 10 themes: Oral Health Related Quality Of Life; Temporomandibular Joint Dysfunction; Masticatory Limitation; Sleep Apnoea; Traumatic Dental Injury; Tooth Surface Loss; Change Over Time; Periodontal Injury; Restorative Difficulty; and Functional Shift and Dual Bite. A deductive approach was used to draw conclusions from the evidence available within each theme.

RESULTS

The narrative literature review established 27 conclusions, indicating that those living with a severe malocclusion may be predisposed to a range of potential consequences. With the exception of Oral Health Related Quality Of Life, which is poorer in adults with severe malocclusion than those with normal occlusions, and the risk of Traumatic Dental Injury, which increases when the overjet is >5 mm in the permanent and 3 mm in the primary dentition, the evidence supporting the remaining conclusions was found to be of low to moderate quality and at high risk of bias.

CONCLUSION

This article summarises the findings of a comprehensive narrative literature review in which all of the relevant research evidence within a substantive investigative area is established and evaluated. Notwithstanding limitations regarding the quality of the available evidence; when combined with clinical expertise and an awareness of individual patient preferences, the conclusions presented may facilitate the orthognathic shared decision-making process and furthermore, may guide the development of the high-quality longitudinal research required to validate them.

Gastric emptying rate of a solid meal in patients with anterior open bite malocclusion: A preliminary study

Objectives:

The objective of the study was to investigate the relationship between anterior open bite (AOB) malocclusion and digestion by evaluating mastication and gastric emptying (GE) of a solid meal.

Material and Methods:

We recruited 26 female participants and divided them into two groups according to their occlusion status: The control group with normal occlusion (n = 11; age: 25.2 ± 2.8 years; and body mass index [BMI]: 21.1 ± 1.9 kg/m2) and the AOB group with AOB malocclusion (n = 15; age: 23.2 ± 5.5 years; BMI: 21.0 ± 1.6 kg/m2). GE, chewing, and occlusion were assessed simultaneously. A food questionnaire survey was also administered on the same day.

Results:

A significant positive correlation was noted between open bite and the occlusal analysis findings. Negative correlations were found between the food questionnaire score and both the open bite and occlusal analysis findings, which confirmed that AOB affects mastication. However, no significant difference in the GE rate parameters was observed between the two groups.

Conclusion:

Adaptive mechanisms may have a compensatory effect on the GE rate. However, the lack of tooth contact in the anterior occlusal region resulted in reduced masticatory ability. Orthodontic treatment should thus be considered, regardless of the presence of digestive problems, to improve mastication.

Sagittal Condylar Inclination and Transversal Condylar Inclination in Different Skeletal Classes

Background: During prosthodontic treatment, the averaged values of the transversal condylar inclination (TCI) and the sagittal condylar inclination (SCI) are used for articulator settings. This study evaluated different parameters of measurable mandibular movements according to skeletal classes. Methods: Seventy-five patients (mean age 30.8 ± 5.49) had a condylography using the Cadiax Compact device (Gamma Dental, Klosterneuburg, Austria) and cephalometric analysis performed. Statistical analysis was performed using R statistical software. Results: There was no statistical evidence to state that the value of SCI angle is different in I compared to II Skeletal Class. There were no statistically significant differences when comparing the I vs. III and II vs. III Skeletal Class. The lowest mean SCI angle values were found in subjects with Skeletal Class III. There were statistically significant differences in left-sided TCI between Class I and II. There was a statistically significant linear relationship between ANB angle value and SCI value. Conclusions: Due to the wide individual variation in SCI and TCI values, it is advisable to use individual measurable parameters of mandibular movements during prosthetic reconstructions. The statistically significant relationship between SCI and ANB angle can be used to individualize the articulating parameters, especially in significant skeletal disproportions.

The Frequency of Temporomandibular Disorders, Surgical Complications, and Self-Reported Mental Health Problems in Orthognathic Patients

OBJECTIVE

To evaluate the frequency of signs and symptoms of temporomandibular disorders (TMD), surgical complications, and patient's self-reported mental health problems during orthognathic treatment.

MATERIAL AND METHODS

The clinical records of 145 patients treated with orthognathic treatment were retrospectively studied. Variables regarding occlusal parameters, treatment duration, TMD symptoms, complications, and self-reported mental health status at time points of T0 (beginning of the treatment), T1 (before surgery), and T2 (final examination) were evaluated. The variables were statistically compared with significance level of P < 0.05.

RESULTS

A total of 51% (n = 74) of the patients had TMD symptoms at 1 or several time points, women having significantly more TMD signs and symptoms (P = 0.002). Temporomandibular disorder signs and symptoms decreased significantly after orthognathic treatment (P=0.001). At least 1 self-reported mental health-related factor during 1 or several time points (T0-T2) was recorded in 17.2% (n = 25) of the patients. There was no significant difference in frequency of self-reported mental health problems in patients with TMD signs and symptoms compared with patients without TMD signs and symptoms (P > 0.05). The frequency of postoperative complications was 39.3%, being significantly higher after Bilateral Sagittal Split Osteothomy (BSSO, 48.7%). There was no difference in treatment duration of patients with self-reported mental health problems compared with patients without (P > 0.05).

CONCLUSIONS

In this study population, TMD signs and symptoms seem to be typical both in patients with or without self-reported mental health problems. Women had significantly more TMD symptoms. Orthognathic surgery treatment seems to have a positive effect on TMD signs and symptoms.

Dentofacial deformity and orthognatic surgery: Influence on self-esteem and aspects of quality of life

This study aimed to assess the extent to which psychosocial and functional aspects are affected in orthognathic surgery patients. The Oral Health Impact Profile (OHIP-CRO14), Orthognathic Quality of Life Questionnaire and Self-Esteem (SE) Scale were used. The sample included 110 Caucasian subjects (73% females) aged 19-54 years. Fifty-five patients with dentofacial deformities were treated by combined orthodontic-orthognathic surgical treatment, and 55 others, matched by sex and age, were untreated controls without dentofacial deformities. In comparison with the untreated subjects, patients before surgery had a poorer quality of life, with the largest effect size in oral function (OF) and OHIP (average differences 8.0 and 14.7, respectively; p < 0.001; r = 0.65 and 0.63), while the lowest effect sizes were in awareness of facial aesthetics (AW) and SE. The treatment induced statistically significant changes in all psychosocial and functional aspects, mainly with a large effect size (p < 0.001; r = 0.48-0.78). The major effect size was a decrease in facial aesthetic concerns (FE; 7.6 ± 6.2; p < 0.001; r = 0.78), followed by a decrease in impairment of OF and OHIP (8.0 ± 7.1 and 16.6 ± 14.6; p < 0.001; r = 0.75). The lowest effect size was in the decrease in AW and increase in SE. After surgery, all aspects were similar to those in the untreated subjects. In conclusion, facial deformity raises many issues, primarily related to aesthetic concerns and functional impairment; however, orthognathic surgery manages to improve quality of life to be similar to that of the population without deformities.

The Effect of Orthognathic Surgery on Temporomandibular Joint Function and Symptoms: What are the Risk Factors? A Longitudinal Analysis of 375 Patients

PURPOSE

The effects of orthognathic surgery (OGS) on the temporomandibular joint (TMJ) are still controversial. Based on a high-volume uniform collective, the function and clinical symptoms of the TMJ and the dysfunction index (Di) by Helkimo were evaluated prior and up to 2 years after OGS.

METHODS

A longitudinal cohort study was performed between 2006 and 2016. A comprehensive examination focusing on TMJ function, temporomandibular disorder (TMD) symptoms, and the Di had been performed preopertaively (T0) and postoperatively at 6 weeks (T1), 6 months (T2), 1 year (T3), and 2 years (T4). The predictor variables used were sex, age, skeletal class, type of surgery, and amount of dysfunction or number of TMD complaints before treatment. The outcome of this study was TMD symptoms and the Di. Descriptive and bivariate statistics were computed, and the significance level was set at P < .05.

RESULTS

The sample consisted of 375 patients (247 women, 128 men, mean age 28.1 ± 9.4 years), 269 with skeletal Class II (71.7%) and 106 with skeletal Class III (28.3%) treated with sagittal split osteotomy bilateral sagittal split osteotomy (n = 173) or Le Fort I and bilateral sagittal split osteotomy (n = 202). Severe signs of dysfunction (Di 2/3) were seen in 5.9% of the patients before OGS and in 2.1% of the patients 2 years after OGS. The difference in Di (Di0/1 and Di2/3) between T0 and T1/T2 was statistically significant (P = .028; P = .011, respectively). TMD symptoms were significantly reduced 2 years after OGS (P = .028). Female gender (P = .013), skeletal Class II (P < .001), and counterclockwise rotation (P < .001) were the only risk factors significantly associated with the occurrence of TMD at T1.

CONCLUSIONS

The results of this study suggest that in most cases TMD symptoms can be significantly reduced and only a few can be induced with OGS. No risk factors were found for long-term effects on the TMJ.

Racial Disparities in Complications, Length of Stay, and Costs Among Patients Receiving Orthognathic Surgery in the United States

INTRODUCTION

Black and Hispanic/Latino patients in the United States often experience poorer health outcomes in comparison to White patients. We aimed to assess the impact of race on complications, length of stay, and costs after orthognathic surgery.

METHODS

Pediatric and young adult orthognathic surgeries (age <21) were isolated from the Kids Inpatient Database from 2000-2012. Procedures were grouped into cohorts based on the preoperative diagnosis: apnea, malocclusion, or congenital anomaly. T tests and χ² analyses were employed to compare complications, length of stay (LOS), and costs among Black, Hispanic, Asian/Pacific Islander, and other patients in comparison to White patients. Multivariable regression was performed to identify associations between sociodemographic variables and the primary outcomes. Post-hoc χ² analyses were performed to compare proportions of patients of a given race/ethnicity across the 3 surgical cohorts.

RESULTS

There were 8,809 patients identified in the KID database (mean age of 16.3 years). Compared to White patients, complication rates were increased among Hispanic patients (2.1 vs 1.3%, P = .037) and other patients treated for apnea (8.7 vs 0.83%, P = .002). Hospital LOS was increased in both Black (3.3 vs 2.1 days, P < .001) and Hispanic (2.9 days, P < .001) patients. Costs were higher than Whites ($35,633.47) among Hispanic ($48,029.15, P < .001), Black ($47,034.41, P < .001), and Asian/Pacific-Islander ($44,192.49, P < .001) patients. White patients comprised a larger proportion of the malocclusion group (77.8%) than apnea (66.9%, P < .001) or congenital anomaly (59.1%, P < .001), while the opposite was true for Black, Hispanic, and Asian/Pacific-Islander patients.

CONCLUSION

There are significant differences in complications, LOS, and costs after orthognathic surgery among patients of different race/ethnicity. Further studies are needed to better understand the causes of disparity and their clinical manifestations.

Craniofacial Morphology Affects Bite Force in Patients with Painful Temporomandibular Disorders

Craniofacial morphology affects masticatory performance in healthy dentate subjects, but little is known about its effects in patients with painful temporomandibular disorders (TMDs). Forty-eight female patients (mean age of 28±5.8 years) with painful TMDs underwent lateral cephalometric radiography. Using Ricketts' cephalometric analysis and the Vert method, subjects were assigned to three groups according to their craniofacial morphology: brachyfacial (n=22), mesofacial (n=13), and dolichofacial (n=13). Research diagnostic criteria for TMD were used to confirm the TMD diagnosis for each patient. Pain intensity was reported by each patient based on a visual analog scale (VAS). Maximum bite force (MBF) was measured with pressure sensors placed on the first molar site. Masticatory performance (MP) was assessed by chewing a silicone-based artificial material and determining the resulting particle size by the sieve method. Chewing ability (CA) was evaluated for seven food types and analyzed by a VAS questionnaire. Data were analyzed by one-way ANOVA followed by a Tukey-Kramer test (p<0.05). MBF differed in each group, with brachyfacial patients having the highest MBF values. There was no difference in MP among the groups. The groups differed only in their ability to chew one of the seven evaluated food types. In summary, craniofacial morphology affects the MBF without impairing MP or CA in patients with painful TMDs.

Three-dimensional mandibular motion in skeletal Class III patients

OBJECTIVE

The aim of the study was to analyze the characteristics and changes in mandibular condylar motion in patients with skeletal Class III malocclusion.

METHODS

Using a 3D motion analyzer, mandibular movements were recorded in 9 patients with skeletal Class III malocclusion and 22 control subjects with Angle Class I jaw relationships.

RESULTS

Class III patients had a similar interincisor point displacement but a significantly reduced displacement of both condyles on the sagittal and frontal planes, with smaller translation paths than control subjects (right -9.4 mm; left -4.8 mm). The overall condylar rotation component was larger in Class III patients (right +8.8%; left +7.3%). The largest inter-group significant differences were observed in the first 10% of mouth opening, in which Class III patients had a larger rotating component than control subjects (+20%, p < 0.01).

CONCLUSIONS

Condylar motion was reduced in skeletal Class III patients, in particular in the translational path.