Anterior Crossbite Research Articles

Non-coding RNA alterations in occlusal disharmony-induced anxiety-like behaviour.

Occlusal disharmony (OD) may induce anxiety-like behaviours; however, the underlying mechanism remains unclear. Herein, we explored the expression profiles of non-coding RNAs (ncRNAs), along with their biological function and regulatory network, in anxiety-like behaviour induced by OD. Occlusal disharmony was produced by anterior crossbite of C57BL/6 mice. Behavioural tests, corticosterone (CORT) and serotonin (5-HT) levels were used to measure anxiety. In addition, RNA sequencing was used to screen all differentially expressed (DE) ncRNAs. Moreover, the RNA-binding proteins interacting with ncRNAs were predicted by the ENCORI database and confirmed using western blots. The significant differences in behavioural tests and CORT suggested the successful induction of anxiety-like behaviour by OD. In OD mice, ncRNAs were significantly dysregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses suggested that the DE ncRNAs were enriched in anxiety-related pathways. CircRNA10039 was upregulated, and PTBP1 was predicted to interact with circRNA10039. In addition, KEGG pathway analysis showed that PTBP1 may be associated with messenger RNA biogenesis and spliceosomes. OD induced by anterior crossbite can lead to the anxiety-like behaviours. During this process, ncRNA also changes. CircRNA10039 and PTBP1 may play a role in OD-induced anxiety-like behaviours.

Type V collagen exhibits distinct regulatory activities in TMJ articular disc versus condylar cartilage during postnatal growth and remodeling

Understanding matrix molecular activities that regulate the postnatal growth and remodeling of the temporomandibular joint (TMJ) articular disc and condylar cartilage will enable the development of effective regenerative strategies targeting TMJ disorders. This study elucidated the distinct roles of type V collagen (collagen V) in regulating these two units. Studying the TMJ of young adult Col5a1+/− mice, we found that loss of collagen V resulted in substantial changes in the proliferation, clustering and density of progenitors in condylar cartilage, but did not have a major impact on disc cells that are more fibroblast-like. Although loss of collagen V led to thickened collagen fibrils with increased heterogeneity in the disc, there were no significant changes in local micromodulus, except for a reduction at the posterior end of the inferior side. Following the induction of aberrant occlusal loading by the unilateral anterior crossbite (UAC) procedure, both wild-type (WT) and Col5a1+/− condylar cartilage exhibited salient remodeling, and Col5a1+/− condyle developed more pronounced degeneration and tissue hypertrophy at the posterior end than the WT. In contrast, neither UAC nor collagen V deficiency induced marked changes in the morphology or biomechanical properties of the disc. Together, our findings highlight the distinct roles of collagen V in regulating these two units during postnatal growth and remodeling, emphasizing its more crucial role in condylar cartilage due to its impact on the highly mechanosensitive progenitors. These results provide the foundation for using collagen V to improve the regeneration of TMJ and the care of patients with TMJ disorders. Statement of significanceSuccessful regeneration of the temporomandibular joint (TMJ) articular disc and condylar cartilage remains a significant challenge due to the limited understanding of matrix molecular activities that regulate the formation and remodeling of these tissues. This study demonstrates that collagen V plays distinct and critical roles in these processes. In condylar cartilage, collagen V is essential for regulating progenitor cell fate and maintaining matrix integrity. In the disc, collagen V also regulates fibril structure and local micromechanics, but has a limited impact on cell phenotype or its remodeling response. Our findings establish collagen V as a key component in maintaining the integrity of these two units, with a more crucial role in condylar cartilage due to its impact on progenitor cell activities.

Occlusal disharmony promotes anxiety-like behaviours by suppressing Sirt1.

Previous studies have indicated that occlusal disharmony (OD) can promote anxiety-like behaviours. However, the specific molecules involved in the development of anxiety-like behaviours and their underlying mechanisms remain unknown. OD was produced by anterior crossbite of female mice. We measured the anxiety levels of mice in each group and screened the hippocampal mRNA expression profiles of mice in the control group and OD group. The role of target mRNA in OD-induced anxiety-like behaviours was evaluated and we preliminarily explored the possible downstream pathways. The results suggested that OD can induce and promote anxiety-like behaviours with/without chronic unpredictable mild stress. We found that Sirt1 was significantly downregulated within the hippocampus in OD mice. In addition, the downregulation of Sirt1 within the hippocampus in OD and control mice promoted anxiety-like behaviours, increased acetylated histone H3 expression and decreased Dnah12 transcription levels. In contrast, in OD mice subjected to an injection of resveratrol, there was a remission of anxiety-like behaviours and an upregulation of Sirt1 in the hippocampus, the effects of which were accompanied by decreased acetylated histone H3 expression and increased Dnah12 transcription levels. OD leads to increased sensitivity to chronic stress in mice, resulting in anxiety-like behaviours. During this process, Sirt1 acts as an effective factor in the regulation of OD-induced anxiety-like behaviours. OD, as a stressor, could induce anxiety-like behaviours. It investigates the impact of OD (a stressor) on the molecular genetic of the pathophysiology of major neuropsychiatric disorders.

Effects of occlusal hypofunction on root surface area in patients exhibiting anterior crossbite in skeletal Class III malocclusion: a CBCT study

ABSTRACT Purposes To evaluate and compare the effects of occlusal hypofunction on root surface areas (RSAs) of permanent teeth in patients with Class III and Class I skeletal relationships. Materials and Methods Thirty-two CBCT images of all permanent maxillary and mandibular teeth, except the third molars, from 16 patients (mean age 23.71 ± 4.04 years) exhibiting Class III skeletal relationships and 16 patients (mean age 24.53 ± 4.91 years) exhibiting Class I skeletal relationships were imported into the Mimics software version 15.01. The outer boundaries of the teeth in two-dimensional images were manually identified on each CBCT slice along the coronal, sagittal, and axial planes to construct three-dimensional models. The tooth models were transferred into 3-matic version 7.01 to specify cementoenamel junctions and calculate RSAs. Intra-examiner reliability was assessed using the intra-class correlation coefficient. The RSAs of each tooth type from the two groups were illustrated and compared using independent t-tests (p < 0.05). Results The RSAs of the maxillary second molars in the skeletal Class III group were significantly higher than those in the skeletal Class I group. There were no significant differences in RSAs between the two groups regarding other tooth types. Conclusions Young adults exhibiting Class III skeletal relationships exhibited significantly greater RSAs in the maxillary second molars. This might be related to occlusal hypofunction during dental root formation.

A novel approach for posterior bite collapse in an adult with crossbite anterior using a 3D-printed bite riser

Background: Managing an adult patient presenting with an anterior crossbite in conjunction with posterior bite collapse (PBC) is a difficult challenge. Purpose: The purpose of this case study is to highlight the accuracy that can be attained with the utilization of a three-dimensional (3D) printed bite riser in the correction of PBC accompanied by an anterior crossbite in an adult patient with Class III malocclusion. Case: A 64-year-old male complained of being unable to chew properly. Extraoral examination revealed a concave profile with a protrusive mandible. The patient exhibits a 5 mm anterior crossbite and has missing lower posterior molars, resulting in bilateral PBC. The cephalometric analysis revealed skeletal Class III patterns (SNA: 82.19o; SNB: 86.34o; ANB: -4.15°), with protrusion and counterclockwise rotation of the mandible (SN-OP: 3.84o). Case Management: By utilizing a 3D-printed bite riser in conjunction with temporary anchoring devices (TADs), it is possible to resolve the issue of an anterior crossbite accompanied by PBC. This is achieved by repositioning the elongated posterior segments on both sides of the maxilla to generate vertical space for mandibular tooth rehabilitation, retracting the anterior segment, and narrowing the lower arch. Simultaneously, the crossbite on both sides was corrected, a Class I and ideal overbite and overjet were achieved, the occlusal vertical dimension increased, the occlusal plane angle was corrected (7.51o), and an acceptable ANB angle (-1.36°) was accomplished. The treatment lasted 18 months and yielded sustained results after a one-year retention period. Conclusion: Integrating 3D printing technology in orthodontic treatment offers numerous options for managing challenging cases such as PBC while also reducing the treatment length. The patient was satisfied with the results achieved.

Current Trends in Pediatric Orthodontics: A Comprehensive Review.

Pediatric orthodontics is a critical field focusing on the diagnosis, prevention, and treatment of dental and facial irregularities in children. This comprehensive review explores current trends and methodologies in pediatric orthodontics and discusses the multifactorial etiology of malocclusions, including genetic, environmental, and disease-related factors. The importance of proper diagnosis is highlighted, and the extraoral, intraoral, and functional evaluations essential for effective treatment planning are detailed. Various orthodontic conditions such as Class III and Class II malocclusions, abnormal oral habits, arch length discrepancies, anterior and posterior crossbites, open bites, and deep bites are examined in depth. The review also addresses the role of temporomandibular joint disorders (TMDs) and obstructive sleep apnea (OSA) in pediatric patients, emphasizing the need for early and accurate diagnosis to facilitate appropriate intervention. The use of clear aligners in early orthodontic intervention is evaluated given their efficacy and improved patient satisfaction compared to traditional appliances. Additionally, the article discusses the non-advisability of early interception for certain self-correcting malocclusions and the limitations of pediatric orthodontic treatment, including compliance-related issues and the unique anatomical considerations of deciduous dentition. This review aims to provide a detailed understanding of contemporary practices and challenges in pediatric orthodontics, offering insights for clinicians to enhance treatment outcomes and patient care.

PREVALENCE OF MALOCCLUSION IN CHILDREN WITH MIXED DENTITION IN VISNAGAR: A CROSS-SECTIONAL RETROSPECTIVE STUDY

Background: Malocclusion is currently understudied in the literature in Visnagar town of Gujarat Therefore, thecurrent research aimed to ascertain the prevalence of malocclusion and its various paradigms among children with mixed dentition of age between 6-14 years. Aim: To establish the Prevalence of various aspects of malocclusion amidst children ages, 6-14 years who visited the department of Pediatric dentistry - A Retrospective Study. Methodology: A Retrospective, Cross-Sectional study among children aged 6-14 years was conducted for the duration of 2020-22. The data was gathered in terms of intraoral photographs of children with mixed dentition phases. Out of the total 350 patient photographs assessed, 150 adhered to the conditions for inclusion. Various Occlusal traits like molar relations, midline shift, open bite, crossbite, and scissor bite were evaluated. The Association of age and gender specificity of various occlusal traits was assessed and tabulated. Results:Class 1 malocclusion was most prevalent among children (66.3%) followed by End on the relation (22%), Class 2 division 1 (7.3%), Class 3 (3.3%), and least seen was Class 2 division 2 (0.6%). Crossbite prevalence was 17.3%, among which the most commonly seen was Anterior single teeth crossbite (58%) and the least observed was unilateral segmental crossbite (4%). Reverse overjet and Overbite observed were 4% and 2% respectively Conclusion: Early diagnosis of developing malocclusion would facilitate appropriate interception in mixed dentition with better outcomes.

Malocclusion in deciduous dentition: a cross-sectional study in a Portuguese preschool population

PurposeTo determine the prevalence of malocclusion in Portuguese preschool children, to characterise occlusion in the deciduous dentition, and to study the relationship between malocclusion, sex, and age.MethodsThis cross-sectional study included 3–6 years old children, from 25 randomly selected kindergartens from the Lisbon district. Data were collected through an oral examination. Malocclusion was defined as the presence of any type of occlusion anomaly (anterior crossbite, edge-to-edge, increased overjet, open bite, deep overbite, posterior crossbite, scissor bite), spacing anomaly (crowding), or dentition anomaly (supernumerary teeth, agenesis, malformations). Canine class, terminal plane of the deciduous second molars and type of Baume arch were also recorded. Statistical analysis included descriptive and chi-squared test (α = 0.05).ResultsThe sample included 426 children with a global prevalence of malocclusion of 60.6%. Occlusion anomalies were the most prevalent (59.2%), the most frequent being deep overbite (27%), increased overjet (22.1%) and posterior crossbite (14.1%). Crowding had a prevalence of 1.6% and agenesis of 1.4%. Class I canine (57.3%), straight second molar terminal plane (60.1%) and type I Baume arch (53.3%) were the most common. The mean overjet was 2.6 mm (sd = 2.1) and the mean overbite was 2.2 mm (sd = 2.1). Age was associated with the presence of occlusion anomalies (p = 0.03), and increased overjet prevalence was found to be higher in girls (p = 0.03).ConclusionsThe prevalence of malocclusion was high, with occlusion anomalies being the most prevalent. It is important to identify modifiable risk factors associated with malocclusion to prevent this condition in both the deciduous and permanent dentitions.

Class III correction and enhanced periodontal health with aligner treatment in a 53-year-old patient.

In this case report, we describe the successful camouflage treatment of a 53-year-old female with dental and skeletal Class III malocclusion combined with anterior crossbite, gingival recession, and mobility of the lower incisors, using clear aligners. The treatment involved periodontal debridement followed by orthodontic treatment. The mandibular posterior teeth were distalized to correct the anterior crossbite and to establish Class I molar relationships. During treatment, the mandibular incisors were intruded, and the mandibular occlusal plane underwent a clockwise rotation due to slight extrusion of the maxillary buccal segments and distalization of the mandibular posterior teeth. Following treatment, all objectives were achieved, including resolution of the anterior crossbite, significant reduction of gingival recession and tooth mobility, and improved functional occlusion. The dental and skeletal Class III malocclusion was corrected, and the marginal alveolar bone dehiscence was significantly reduced. The results remained stable over a 3-year retention period, with enhanced molar intercuspation and gingival growth progression. This case adds to the evidence supporting the adaptability and effectiveness of clear aligners in treating orthodontic patients with compromised periodontium. The treatment outcomes support that orthodontic treatment using clear aligners, combined with periodontal monitoring, can assist in managing alveolar bone defects, gingival recession, and tooth mobility.

Up-regulation of IL-1β and sPLA2-III in the medial prefrontal cortex contributes to orofacial and somatic hyperalgesia induced by malocclusion via glial-neuron crosstalk

The medial prefrontal cortex (mPFC) has been identified as a key brain region involved in the modulation of chronic pain. Our recent study demonstrated that unilateral anterior crossbite (UAC) developed the comorbidity model of temporomandibular disorders (TMD) and fibromyalgia syndrome (FMS), which was characterized by both orofacial and somatic hyperalgesia. In the present study, UAC rats exhibited significant changes in gene expression in the mPFC. Enrichment analysis revealed that the significantly involved pathways were cytokines-cytokine receptor interaction and immune response. The expression of group III secretory phospholipase A2 (sPLA2-III) was significantly increased in the mPFC of UAC rats. Silencing sPLA2-III expression in the mPFC blocked the orofacial and somatic hyperalgesia. Immunofluorescence showed that sPLA2-III was mainly localized in neurons. The expression of interleukin-1β (IL-1β) in the mPFC significantly increased after UAC. Injection of IL-1β antibody into the mPFC blocked orofacial and somatic hyperalgesia. IL-1β was mainly localized in microglia cells. Furthermore, injection of IL-1β antibody significantly reduced the expression of sPLA2-III. These results indicate that neuroinflammatory cascade responses induced by glial-neuron crosstalk in the mPFC may contribute to the development of TMD and FMS comorbidity, and IL-1β and sPLA2-III are identified as novel potential therapeutic targets for the treatment of chronic pain in the comorbidity of TMD and FMS.

Prediction of the individual response to treatment of skeletal Class III malocclusions and their long-term stability. A Case Report.

Abstract. Predicting the outcome of the treatment and its stability over time is an invaluable tool for the clinician when initiating therapy for correction of class III skeletal malocclusions. This work reports the predicted response to treatment of a 5-year-old female patient with skeletal Class III malocclusion and its long-term stability. The individual prediction cephalometric model of Baccetti and Franchi was applied in this case. As a result of the predictive equation, an in-dividual value of -0.958 was obtained (norm = -0.4065), which predicted a “very good response to treatment”. The Class III malocclusion and anterior crossbite were corrected, and the profile was harmonized with rapid maxillary expansion (RME) and a facemask projecting the maxilla forward 12 mm, in addition to the mandible’s 9° total downward rotation. After 15 years and three months of com-pleting the treatment, the stability of the results was confirmed. In conclusion, the individual prediction cephalometric model used in this case report allowed us to accurately predict the results in facial, skeletal and dental changes and the long-term stability of the treatment of class III skeletal malocclusion.

Temporomandibular joint disc responses to installation and removal of the experimental malocclusion.

Aberrant occlusion and aging are two main risks for temporomandibular joint (TMJ) degeneration. To assess the combined impact of occlusion and age on TMJ disc. To avoid the confounding impact of gender, presently, 126 female C57BL/6J mice, 63 youngsters, 6-week old and 63 adults, 28-week old, were used. An experimental bilateral anterior crossbite (BAC) relation was created by installing metal tubes onto the mandibular incisors. Mice were sacrificed at 3, 7 and 11 weeks (n = 9). Additionally, the installed tubes were removed at 7 weeks in removal groups and the TMJs were sampled after another 4 weeks (n = 9). Disc changes were detected by histomorphology, immunohistochemistry, and western blot assays. Disc deformation was obvious in BAC groups. The typical change was hyperplasia at the posterior region of the disc where there was significant infiltration of inflammatory cells. Expressions of the inflammatory markers, including tumour necrosis factor-α and interleukin-1β, and the catabolic markers, including fibronectin (FN), FN N-terminal fragments, and vascular endothelial growth factor-A, were all increased. The changes were more obvious in adults than in youngsters. Removal of BAC attenuated inflammatory and catabolic changes in the youngsters, but the inflammatory markers recovered little in the adults. TMJ disc responds to BAC by degeneration and inflammation, and respond to BAC removal by rehabilitation. Adult discs show severer degeneration responses to BAC and a lower level of anti-inflammatory capability to BAC removal than the youngster's discs. Animals cannot be equated with humans. The human disc response to occlusion changes worth further exploration.

The effect of early childhood non-nutritive sucking behavior including pacifiers on malocclusion: a randomized controlled trial.

Systematic reviews on the effects of pacifiers on occlusion have highlighted the need for quality RCTs. Single region, three parallel-armed, prospective, randomized controlled trial. To investigate the correlations between early childhood non-nutritive sucking habits and malocclusion. Specifically to test whether the use of a study pacifier has differing effects compared to other pacifiers and control, and whether the duration of pacifier use or digit sucking influence the occlusion. The subjects were firstborn children, born in 2008 in Vantaa, Finland. One-third of participants were offered study pacifiers, free of charge, from birth up to 2 years of age. The history of the subjects' sucking habits, including pacifier use was screened in a questionnaire at the age of 2 years, and clinical examinations were performed at the age of 7 years. In addition, the subjects were divided into groups that were equally matched regarding their mother's level of education. Posterior crossbite, anterior crossbite, overjet, deep bite, open bite, and crowding. Three districts were randomly allocated to three study groups by drawing lots. It was not possible to blind the clinicians or parents from the intervention. Blinding during data analysis was performed. From the original cohort of 2715 children born in the town of Vantaa, 1911 were excluded and 353 were lost to follow-up. The remaining 451 children were divided into three groups according to the use of pacifiers. The prevalence of posterior crossbite at the age of 7 years was higher if a non-study pacifier had been used (P = .005) even when matched for the mother's level of education (P = .029). The prevalence of posterior crossbite was higher if the pacifier habit had continued for 12 months or more compared to 11 months or less, 7% and 1%, respectively, (P = .003). Digit sucking for 12 months or more was associated with crowding (P = .016). The prevalence of crossbite in the study pacifier group was less than in control pacifiers. No adverse harms were reported other than effects on the dentition. The use of pacifiers is associated with the posterior crossbite, especially if their use continues for a year or more. Parents/guardians should be advised to stop the use or reduce the use of pacifiers to a minimum after their child's first birthday. ClinicalTrials.gov NCT01854502.

Deletion of vitamin D receptor exacerbated temporomandibular joint pathological changes under abnormal mechanical stimulation

AimsTemporomandibular disorder can cause degenerative pathological changes by aseptic inflammation in the temporomandibular joint (TMJ). Vitamin D (VD) is known for maintaining calcium homeostasis, and recent studies indicated that VD and the vitamin D receptor (VDR) are important in inflammatory responses. In this study, we explored the anti-inflammatory effect of VD-VDR signaling axis in TMJ pathological degeneration. Main methodsMice ablated for Vdr (Vdr−/−res) were fed with a rescue diet to avoid hypocalcemia. With abnormal mechanical stimulation, unilateral anterior crossbite (UAC) induced temporomandibular disorders in mice. Histological staining, immunohistochemistry staining, and micro-CT analysis were performed to evaluate TMJ pathological changes. To identify the mechanisms in the aseptic inflammatory process, in vitro experiments were conducted on wild-type (WT) and Vdr−/− chondrocytes with compressive mechanical stress loading, and the related inflammatory markers were examined. Key findingsVdr−/−res mice did not develop rickets with a high calcium rescue diet. The TMJ cartilage thickness in Vdr−/−res mice was significantly decreased with mechanical stress stimulation compared to WT mice. UAC-induced bone resorption was obvious, and the number of osteoclasts significantly increased in Vdr−/−res mice. The proliferation was inhibited and the gene expression of Il1b, Mmp3, and Mmp13 was significantly increased in Vdr−/− chondrocytes. However, WT chondrocytes showed significantly increased Tnfa gene expression as a response to mechanical stress but not in Vdr−/− chondrocytes. SignificanceVD-VDR is crucial in TMJ pathological changes under abnormal mechanical stimulation. Deletion of Vdr exacerbated inflammatory response excluding TNFα, inhibited chondrocyte proliferation, and promoted bone resorption in TMJ.

Deletion of Bmal1 in aggrecan-expressing cells leads to mouse temporomandibular joint osteoarthritis.

Articular cartilage is the major affected tissue during the development of osteoarthritis (OA) in temporomandibular joint (TMJ). The core circadian rhythm molecule Bmal1 regulates chondrocyte proliferation, differentiation and apoptosis; however, its roles in condylar cartilage function and in TMJ OA have not been fully elucidated. TMJ OA mouse model was induced by unilateral anterior crossbite (UAC) and Bmal1 protein expression in condylar cartilage were examined by western blot analysis. To determine the role of Bmal1 in TMJ OA, we generated cartilage-specific Bmal1 conditional knockout (cKO) mice (Bmal1Agc1CreER mice) and hematoxylin and eosin staining, toluidine blue and Safranin O/fast green, immunohistochemistry, TUNEL assay, real-time PCR analysis and Western blot assay were followed. Bmal1 expression was reduced in condylar cartilage in a TMJ OA mouse model induced by UAC. The Bmal1 cKO mice displayed decreased cartilage matrix synthesis, reduced chondrocyte proliferation, increased chondrocyte hypertrophy and apoptosis as well as the upregulation of YAP expression in TMJ condylar cartilage. We demonstrated that Bmal1 was essential for TMJ tissue homeostasis and loss-of-function of Bmal1 in chondrocytes leads to the development of TMJ OA.

Craniosynostosis: orofacial and oral health perspectives with masticatory insights

BackgroundCraniosynostosis (CS), premature fusion of one or more cranial sutures, leads to abnormal skull development, impacting both facial esthetics and oral function. This study aimed to evaluate the specific orofacial and oral health characteristics, including masticatory performance, in Thai patients with CS.MethodsA comparative study was conducted with Thai CS patients aged 6–17 years and a control group of healthy individuals with similar age distribution. Assessments included craniofacial morphology, oral health status, and masticatory performance. Intergroup comparisons utilized appropriate statistical tests.ResultsThe study included 24 CS patients with a mean age of 10.11 ± 2.98 years and 30 controls. CS patients exhibited a significantly higher prevalence of various oral conditions compared to controls: cleft palate (20.8%), anterior open bite (41.7%), anterior crossbite (54.2%), posterior crossbite (50%), combined anterior–posterior crossbite (45.8%), dental crowding in both maxilla and mandible (50% and 45.8% respectively), congenitally missing teeth (50%), supernumerary teeth (12.5%), and eruption failure (54.2%). Furthermore, CS patients exhibited significantly higher caries prevalence and susceptibility, alongside poorer oral hygiene, compared to controls. Regarding jaw relationships, CS patients exhibited a significantly higher proportion of Angle's Class III malocclusion (50%) compared to the control group, where Class I malocclusion was predominant (50%). Masticatory performance, assessed using the two-color gum mixing ability test, showed significantly higher hue variance in CS patients (0.12 ± 0.07) compared to the control group, indicating reduced chewing performance.ConclusionThis study underscores the significant orofacial and oral health challenges faced by children with CS, including a high prevalence of malocclusions, dental anomalies, elevated caries experience, and compromised masticatory function. These findings emphasize the importance of tailored interventions and comprehensive oral healthcare strategies to address the unique needs of this population and improve their overall quality of life.

Comparative Evaluation of Three Treatment Modalities for Correction of Anterior Crossbite in Pediatric Patients: A Randomized Control Trial

Comparative Evaluation of Three Treatment Modalities for Correction of Anterior Crossbite in Pediatric Patients: A Randomized Control Trial

Treatment of Anterior Crossbite with Inverted Bracket Position, Case Report

Background: Anterior crossbite is an abnormality in the sagittal direction of one or more maxillary anterior teeth against the mandibular teeth. Although the incidence of this case is small, it can cause aesthetic problems, tooth abrasion, caries, gingivitis, bone resorption, and gingival recession. Case Report: A 24-year-old female patient presented with her upper front teeth positioned behind her lower teeth and a noticeable gap between her upper front teeth. She exhibited an anterior crossbite involving teeth 22 to 32, a central diastema, and crowding of the upper and lower front teeth. Treatment was carried out using a fixed orthodontic with an MBT system and the bracket placement of 22 in an inverted position to get a labial torque effect on the roots. Conclusion: The use of pre-adjusted brackets with the MBT system and the placement of the lateral incisive bracket in an inverted position successfully corrected the anterior crossbite in these teeth both at the crown and root without additional wire bending or auxiliary spring.

Biomechanism of abnormal stress on promoting osteoarthritis of temporomandibular joint through Piezo1 ion channel.

This study aimed to investigate whether flow fluid shear stress (FFSS)-mediated signal transduction affects the function of Piezo1 ion channel in chondrocyte and to further explore the role of mechanical overloading in development of temporomandibular joint osteoarthritis (TMJ OA). Immunohistochemical staining was used to determine the expression of Piezo1 in TMJ OA tissue collected from rat unilateral anterior crossbite (UAC) models. Chondrocytes harvested from normal adult SD rats were treated with FFSS (0, 4, 8, 12 dyn/cm2) invitro. Immunofluorescent staining, real-time polymerase chain reaction, western blotting, flow cytometry and phalloidin assay were performed to detect the changes of cellular morphology as well as the expression of Piezo1 and certain pro-inflammatory and degradative factors in chondrocyte. Immunohistochemical analysis revealed that significantly increased Piezo1 expression was associated with UAC stimulation (p < .05). As applied FFSS escalated (4, 8 and 12 dyn/cm2), the expression levels of Piezo1, ADAMTS-5, MMP-13 and Col-X gradually increased, compared with the non-FFSS group (p < .05). Administering Piezo1 ion channel inhibitor to chondrocytes beforehand, it was observed that expression of ADAMTS-5, MMP-13 and Col-X was substantially decreased following FFSS treatment (p < .05) and the effect of cytoskeletal thinning was counteracted. The activated Piezo1 ion channel enhanced intracellular Ca2+ excess in chondrocytes during abnormal mechanical stimulation and the increased intracellular Ca2+ thinned the cytoskeleton of F-actin. Mechanical overloading activates Piezo1 ion channel to promote pro-inflammation and degradation and to increase Ca2+ concentration in chondrocyte, which may eventually result in TMJ OA.

A comprehensive national survey on malocclusion prevalence among Palestinian children

BackgroundThis study aims to evaluate the prevalence of malocclusion and orthodontic features among schoolchildren in the West Bank, Palestine.MethodsA stratified cluster sample of 1278 schoolchildren (620 males, 658 females, mean age 12 years and 5 months (± 0.5)) were examined. Candidates who had not received any previous orthodontic treatment were only included. Dental anomalies like missing and ectopic teeth were recorded. The anteroposterior occlusal relationship was assessed based on Angle classification. Overjet and overbite were measured. Crowding and spacing were recorded subjectively. In addition, crossbite, openbite, and midline displacement were recorded. The chi-square test and descriptive analysis were used statistically.ResultsThe study found Angle Class I molar relationship in 65%, Class II div 1 in 17%, Class II div 2 in 6%, and Class III in 12% of the sample. An overjet (OJ) of more than 4 mm was present in 17%, and 4% had OJ of more than 6 mm; an OJ of at least 0 mm or less in 36%, and 6% had a reverse OJ. A normal overbite was observed in 53%, while 28% had an increase and 19% had a decreased overbite. An anterior openbite (AOB) was present in 9%, and a scissor bite or anterior crossbite in 6% and 14%, respectively. A posterior crossbite was observed in 12% (9% unilateral and 3% bilateral). Midline displacement was found in (9%). Crowding was observed in 35% and 31% and spacing in 24% and 15% of the maxillary and mandibular arches, respectively. A statistically significant relationship between gender and midline shift, a diastema, spacing in the upper arch, and most dental anomalies was found; males were more affected (p < 0.05).ConclusionThis study reported a high prevalence of malocclusion among schoolchildren in Palestine. A collaborative effort should be directed to obtain more monitoring and surveillance of malocclusion more frequently to prevent and control the exacerbation of the problem.