Skeletal Anterior Open Bite Research Articles

Skeletal Anterior Open Bite Attenuates the Chewing-Related Increase in Brain Blood Flow.

The masticatory function of patients with skeletal anterior open bite (OPEN) is reported to be impaired compared with that of patients with normal occlusion (NORM). In this study, we compared brain blood flow (BBF) in patients with OPEN and NORM and investigated the factors related to BBF during mastication in patients with OPEN. The study included 17 individuals with NORM and 33 patients with OPEN. The following data were collected: number of occlusal contacts, jaw movement variables during mastication, and BBF measured with functional near-infrared spectroscopy during chewing. The number of occlusal contacts, maximum closing and opening speeds, closing angle, and vertical amplitude were smaller in the OPEN than in the NORM group. Interestingly, BBF increased less in the OPEN group. Correlation analysis revealed that several parameters, including number of occlusal contacts and closing angle, were correlated with changes in BBF during mastication. These results suggest that not only occlusion but also jaw movement variables and factors related to masticatory muscles contribute to the chewing-related increase in BBF. In conclusion, BBF increases less during mastication in patients with OPEN than in those with NORM. In addition, the higher increase in BBF is correlated with jaw movement. Together, we discovered that OPEN exhibits significant adverse effects not only on masticatory function but also on brain function.

Craniofacial Cephalometric Characteristics and Open Bite Deformity in Individuals with Amelogenesis Imperfecta-A Systematic Review and Meta-Analysis.

Individuals with amelogenesis imperfecta (AI) often present with malocclusions, especially a dental or skeletal anterior open bite (AOB). To evaluate the craniofacial characteristics in individuals with AI. A systematic literature search was conducted with the PubMed, Web of Science, Embase and Google Scholar databases to identify studies relating to the cephalometric characteristics of individuals with AI, without any language or publication date restrictions. The grey literature was searched using Google Scholar, Opengrey and Worldcat. Only studies with a suitable control group for comparison were included. Data extraction and a risk of bias assessment were carried out. A meta-analysis was performed using the random effects model for cephalometric variables that were evaluated in at least three studies. The initial literature search yielded 1857 articles. Following the removal of duplicates and a screening of the records, seven articles were included in the qualitative synthesis, representing a total of 242 individuals with AI. Four studies were included in the quantitative synthesis. The meta-analysis results showed that individuals with AI present a smaller SNB angle and larger ANB angle than those of control groups in the sagittal plane. In the vertical plane, those with AI present a smaller overbite and larger intermaxillary angle than those without AI. No statistically significant differences were found for the SNA angle when comparing the two groups. Individuals with AI seem to present with more vertical craniofacial growth, leading to an increased intermaxillary angle and decreased overbite. This possibly leads to a more retrognathic mandible with a larger ANB angle due to an anticipated posterior mandibular rotation.

Maxillary sinus and alveolar bone levels in subjects with skeletal anterior open bite: Is there room for mini-implant supported molar intrusion?

Objective: To compare the maxillary sinus (MS) and alveolar bone (AB) heights in adult subjects with normal occlusion and those with skeletal anterior open bite (AOB). Study Design: Cross-sectional. Setting: Aga Khan University Hospital, Karachi. Period: December 2020 to June 2021. Material & Methods: The study was conducted on the pretreatment orthodontic records of sixty adult subjects (30 males, 30 females). Skeletal high angle cases with AOB >1 mm were included in skeletal AOB while a matched sample with normal dental and skeletal relationships was included in normal occlusion group. The MS and AB heights were measured on lateral cephalograms and orthopantomograms at interdental regions from maxillary 1st premolar to 2nd molar. The MS and AB heights were compared between males and females and between skeletal AOB group and normal occlusion groups using independent sample t-test. Results: The mean age of the subjects with skeletal AOB (22.68±4.04 years) and those with normal occlusion (23.19±4.68 years) were comparable (p=0.653). In general, MS height and AB heights were greater in males than females. There was no significant difference in the MS height between the skeletal AOB and normal occlusion groups for both genders (p>0.05). However, both males and females with skeletal AOB had greater AB heights between 2nd premolar and 1st molar and between 1st molar and 2nd molar than those with normal occlusion (p<0.05). Conclusion: The MS height in skeletal AOB and normal occlusion groups were comparable. Subjects with skeletal AOB had maximum AB height mesially and distally to maxillary 1st molar that was significantly greater than those with the normal occlusion.

Treatment of an anterior open bite, bimaxillary protrusion and mesiocclusion by the extraction of premolars and the use of clear aligners

Abstract An anterior open bite may be orthodontically treated by either the intrusion of posterior teeth, the extrusion of anterior teeth, or a combination of both. An improvement in bimaxillary protrusion often involves the extraction of premolars and the retraction of the anterior teeth. The treatment of mesiocclusion mainly involves the mesial and/or distal movement of the molars. However, these three types of malocclusions pose significant treatment challenges when using clear aligners. The present case report describes the treatment of a 24-year-old female patient who presented with the above characteristics, which affected her confidence, willingness to smile and masticatory function. A four-premolar extraction plan was designed to resolve the problems using clear aligners as the patient rejected fixed or visible appliances. After 33 months of orthodontic therapy, except for the counter-clockwise rotation of the mandible and the decrease of facial height, the other objectives established in the pre-treatment plan were achieved, and the patient was satisfied with the results. The combination of clear aligners and premolar extractions effectively corrected the skeletal anterior open bite, bimaxillary dentoalveolar protrusion, and mesiocclusion.

Camouflage Treatment of Skeletal Anterior Open Bite with Tongue Training

The aim of this case report was to present an adult patient who suffered from poor occlusal function and poor aesthetic appearance due to skeletal anterior open bite. After orthodontic treatment, she was satisfied with improvements of mastication and esthetics. A case of 20-year-old female with skeletal Class II jaw relationship, mandible retrognathism and anterior open bite without signs and symptoms of temporomandibular disorder. Intraoral examination showed premature contact over bilateral posterior teeth and the forward resting position of tongue. Our treatment plan was orthodontic camouflage with extraction of all first premolars and tongue training. As forward resting position of tongue was noted, a tongue crib soldered on molar bands was used and the patient was instructed with tongue exercises. Normal overbite and overjet were achieved within four years of treatment. Her profile became more harmony after correction of anterior open bite. Although the stability of occlusion relies on the position of tongue, the current masticatory and facial profile provide a better quality of life. Orthodontic treatment of skeletal anterior open bite should be very careful. Appropriate diagnosis, differentiation of etiology and proper selection of mechanics must be verified before initiating treatment.

Evaluation of Soft and Hard Tissue Changes Following the Use of Rapid Molar Intruder for the Management of Skeletal Anterior Open Bite in Mixed Dentition: A Randomized Controlled Trial.

Objective The aim of the study was to evaluate skeletal, dentoalveolar, and soft tissue changes following early anterior open bite (AOB) treatment using a rapid molar intruder (RMI). Materials and methods A two-arm, parallel-group, randomized controlled trial was conducted on 40 patients aged 8-12 years with anterior open bites. They were randomly allocated to the RMI group and the untreated control group (UCG) with a 1:1 allocation ratio. At the beginning of the treatment (T1) and after nine months of treatment (T2), lateral cephalometric images were taken of each patient. The primary outcome measures were skeletal, dentoalveolar, and soft tissue changes. A two-sample t-test was used in the intergroup comparisons of the cephalometric measurement. Results The findings showed that the overbite increased significantly in the RMI group compared to the control group (x= 4.44 mm, x= 0.19 mm, respectively; p<0.001). A statistically significant intrusion of the upper and lower first molars was observed in the RMI group (x= 2.9 mm, x= 1.54 mm, respectively) compared to a slight extrusion in the control group. The differences between the two groups were significant (p<0.001). The SN: GoMe angle and the sum of Bjork decreased significantly in the RMI group compared to an increase observed in the control group. The differences between the two groups were significant (p<0.001). Conclusion The rapid molar intruder is an effective appliance for correcting anterior open bites in mixed dentition, inducing favorable skeletal, dentoalveolar, and soft tissue changes.

Tooth size discrepancy in orthodontic patients with skeletal anterior open bite.

To find out if there is any relationship between tooth size discrepancy (TSD) and skeletal anterior open bite (AOB) and to assess the correlation between the amount of AOB and TSD. A total of 100 Class I subjects were included in this study (average age 15.21 ± 2.84 years). Fifty patients had skeletal AOB (>3 mm) and 50 subjects acted as controls and had a normal overbite. Teeth mesio-distal widths were measured using a digital caliper. Anterior, overall, and posterior TSD ratios were calculated. An independent t-test was employed to assess differences between groups and between genders. Pearson correlation coefficient was used to assess the correlation between the amount of AOB and TSD. Significant differences in anterior (p = .038) and posterior (p = .015) TSD ratios were detected. In the skeletal AOB group, no significant gender differences were detected (p > .05), whereas in the normal bite and total sample group, males had smaller posterior teeth compared to females (p < .05). All the differences were smaller than 1 SD of Bolton's ratios. No significant correlation was found between the amount of AOB and TSD ratios (p > .05). Skeletal AOB had larger anterior and smaller posterior mandibular teeth, but the differences were less than 1 SD of Bolton's ratios. Males have smaller mandibular posterior teeth than females. The amount of AOB is not correlated with the TSD ratios.

A 3D CBCT Analysis of Airway and Cephalometric Values in Patients Diagnosed with Juvenile Idiopathic Arthritis Compared to a Control Group

Introduction: The temporomandibular joint (TMJ) is affected in 30–45% of juvenile idiopathic arthritis (JIA) patients, with all JIA subtypes at risk for TMJ involvement. JIA patients with TMJ involvement may present with altered craniofacial morphology, including micrognathia, mandibular retrognathia, a hyperdivergent mandibular plane angle, and skeletal anterior open bite. These features are also commonly present and associated with non-JIA pediatric patients with obstructive sleep apnea (OSA). Materials and Methods: The study was comprised of a group of 32 JIA patients and a group of 32 healthy control subjects. CBCT images were taken for all patients and were imported into Dolphin Imaging software. The Dolphin Imaging was used to measure the upper airway volumes and the most constricted cross-sectional areas of each patient. Cephalometric images were rendered from the CBCT data for each patient, and the following cephalometric values were identified: SNA angle, SNB angle, ANB angle, anterior facial height (AFH), posterior facial height (PFH), mandibular plane angle (SN-MP), FMA (FH-MP), overjet (OJ), and overbite (OB). Airway volumes, the most constricted cross-sectional area values, and cephalometric values were compared between the JIA and control groups. Results: For airway values, statistically significant differences were seen in the nasopharynx airway volume (p = 0.004), total upper airway volume (p = 0.013), and the most constricted cross-sectional area (p = 0.026). The oropharynx airway volume was not statistically significant (p = 0.051). For cephalometric values, only the posterior facial height showed a statistically significant difference (p = 0.024). Conclusions: There was a significant difference in airway dimensions in the JIA patients as compared to the control patients. In addition, the posterior facial dimensions seem to be affected in JIA patients. The ODDs ratio analysis further corroborated the findings that were significant.

Aesthetic and functional rehabilitation in a patient with anterior skeletal open bite using lithium dissilicate glass-reinforced ceramic: a case report

The aim of this clinical report is to present the replacement of unsatisfactory metal-ceramic crowns of elements 12, 11, 21 and 22, by lithium disilicate glass-reinforced ceramic crowns in a patient with skeletal anterior open bite. A patient sought care at the Dental Hospital at the School of Dentistry of UFU, complaining of odor between the metal-ceramic crowns of the antero-superior teeth. After clinical and radiographic examination, invasion of the biological space was noticed, surgery was indicated in order to restore the biological space. After healing, the pre-existing cast metal posts were masked using an opaque composite resin and the teeth were reprepared for full all-ceramic crowns. Impressions were taken in two steps, using PVS associated to retraction cords. The ceramic copings were obtained in lithium disilicate ceramic, and the veneering was performed by stratification. After testing the ceramics crowns in relation to, fit, function and aesthetic results, cementation was completed using modified absolute isolation, followed by prophylaxis of preparations with pumice and saline, surface treatment of the ceramic restorations and luting using self-adhesive resin cement. Finally, an occlusal splint was produced to control the effects of bruxism and orofacial pain symptoms. The anterior open skeletal bite was a challenging factor for the rehabilitation of this patient; however, one must consider the entire process that the patient would undergo if choosing for orthognathic surgery, and the patient should be aware of the case limitations. In addition, the use of lithium disilicate glass-reinforced ceramics proved the versatility of this material for anterior aesthetic restorations.

The stability of anterior open bite closure after Bi-maxillary osteotomy

<b>Introduction</b>: The aim of this study was to evaluate the long-term success rate of combined surgical-orthodontic therapy of skeletal anterior open bite. <b>Methods</b>: 11 patients with an anterior open bite treated with a combined surgical-orthodontic therapy were retrospectively analysed via lateral cephalometric radiographs and models before treatment, 7–10 days after surgery(T1), one year post-operatively(T2) and two years post-operatively(T3). <b>Results</b>: Ten patients continued to experience a positive overbite at T2. This decreased to 8 at T3. Three patients experienced relapse and had a negative overbite at T3. The average pre-treatment overbite was greater in the positive overbite group compared to the relapse group. Spearman's correlation analysis revealed a correlation between pre-operative maxilla-mandibular plane angle (MMPA) with the overall change in overbite. <b>Conclusions</b>: In conclusion, combined orthodontic-surgical treatment achieves good results for anterior open bite. Patients with a high pre-operative MMPA have a higher risk of relapse. Lower anterior facial height ratio to total anterior facial height (LAFH:TAFH) and the amount of impaction do not significantly contribute to the risk of relapse. Long term stability of overbite for anterior open bite patients should cover around 75% of patients.

Evaluation of the acceleration, skeletal and dentoalveolar effects of low-level laser therapy combined with fixed posterior bite blocks in children with skeletal anterior open bite: A three-arm randomised controlled trial

To evaluate the effectiveness of the low-level laser therapy (LLLT) in accelerating the early treatment of the skeletal anterior open bite (AOB) and to evaluate the associated skeletal and dentoalveolar changes. A three-arm, parallel-group, randomized controlled trial was conducted on 42 patients aged 8-10 years with skeletal AOB. Patients were randomly allocated to three groups: the fixed posterior bite block+low-level laser therapy (FPBB+LLLT) group; the fixed posterior bite block (FPBB) group; and the untreated control group (UCG) in a 1:1:1 allocation ratio. The LLLT dose in the FPBB+LLLT group was applied using 808-nm wavelength Ga-Al-As semiconductor laser device with the energy of 4-joules/point and irradiation time of 16 seconds/point. LLLT was applied in the first visit; then, it was applied on day 3, 7 and 14 of the first month. Afterwards, it was applied every 15 days until the end of the treatment. Lateral cephalometric images were taken at the beginning of the treatment (T0) and at the end of the active phase (T1). The primary outcome measures were the overall time needed to correct the AOB and the skeletal and dentoalveolar changes. The correction of the AOB required significantly less mean time in the FPBB+LLLT group compared to the FPBB group (x̅=7.07, x̅=9.42 months, respectively; P=0.001). The mean upper first molar intrusion in the FPBB+LLLT group was 1.21mm and significantly greater than that of the FPBB group (0.82mm; P=0.018). However, there was a slight mean extrusion of the upper first molar in the UCG (0.32mm). The overall time needed to correct the AOB was shorter in the FPBB+LLLT group. The LLLT appeared to be effective in accelerating orthodontic tooth movement. FPBB alone or LLLT were effective in the early treatment of anterior open bite (AOB). The two interventional groups produced similar dentoalveolar and skeletal changes; most of which were dentoalveolar in the correction of the anterior open bite.

The Stability of Anterior Open Bite Closure After Bimaxillary Osteotomy.

The aim of this study was to evaluate the long-term success rate of combined surgical-orthodontic therapy of skeletal anterior open bite. A total of 11 patients with an anterior open bite treated with a combined surgical-orthodontic therapy were retrospectively analysed via lateral cephalometric radiographs and models before treatment, 7-10 days after surgery (T1), one year post-operatively (T2) and two years post-operatively (T3). Ten patients continued to experience a positive overbite at T2. This decreased to 8 at T3. Three patients experienced relapse and had a negative overbite at T3. The average pre-treatment overbite was greater in the positive overbite group compared to the relapse group. Spearman's correlation analysis revealed a correlation between preoperative maxilla-mandibular plane angle (MMPA) with the overall change in overbite. Friedman's test followed by Bonferroni post-hoc analysis was carried out to identify any statistical significance. In conclusion, combined surgical-orthodontic treatment achieves good results for anterior open bite. Patients with a high pre-operative MMPA have a higher risk of relapse. Lower anterior facial height ratio to total anterior facial height (LAFH/TAFH) and the amount of impaction do not significantly contribute to the risk of relapse. Long-term stability of overbite for anterior open bite patients should be around 75%.

Evaluation of the open-bite Bionator versus the removable posterior bite plane with a tongue crib in the early treatment of skeletal anterior open bite: A randomized controlled trial

Several treatment approaches can be found in the literature about early treatment of open bite. However, no studies have addressed the use of a removable posterior bite plane with a tongue crib (RPBP/C), compared with functional appliances, for treating open-bite cases. The objectives of this trial was to compare the effectiveness of the open-bite Bionator (OBB) and the RPBP/C as an early intervention to correct skeletal open-bite cases in children, in terms of limiting excessive vertical growth of the craniofacial skeletal components and normalizing the developement of the anterior dentoalveolar region. Two-arm, parallel-group randomized controlled trial was conducted. Forty patients with a skeletal anterior open bite (age range: 7.5-10.5 years) were treated at the University of xxxx School of Dentistry in xxxx, xxxx. They were distributed randomly into 2 equal groups: the OBB group (20 patients; mean age: 8.8 ± 1.5 years) and the RPBP/C group (20 patients; mean age: 8.6 ± 1.1 years). Randomization was based on a computer-generated sequence of random numbers. Primary outcome measures were the skeletal and dentoalveolar variables, whereas the secondary outcome measures were the soft-tissue parameters assessed on standardized lateral cephalograms collected before and after 12 months of treatment. Mann-Whitney U tests were used to detect significant differences between the 2 groups. Both the OBB and the RPBP/C appliances induced favorable dental effects. A statistically significant difference was found between the 2 groups in the overbite (P=0.003). Open bite in the OBB group showed a mean closure of 4.91 mm (SD 0.4 mm), and a mean closure of 3.43 mm (SD 0.3 mm) was observed in the RPBP/C group. Dentoalveolar changes at the anterior region were evident, with statistically significant extrusion, and lingual tipping of the maxillary and mandibular incisors (P ≤ 0.05). The results showed no significant differences in the skeletal changes between the 2 groups. The OBB and the upper posterior bite plane with crib were both effective in the early treatment of the skeletal anterior open bite. However, closure of the anterior open bite was mainly due to the dentoalveolar changes at the anterior region of the dental arches.

Electromyographic features and efficacy of orofacial myofunctional treatment for skeletal anterior open bite in adolescents: an exploratory study

BackgroundDue to the multifactorial aetiology and unpredictable long-term stability, skeletal anterior open bite (SAOB) is one of the most intractable conditions for orthodontists. The abnormal orofacial myofunctional status (OMS) may be a major risk factor contributing to the development and relapse of SAOB. This study is aimed at evaluating the OMS and the efficacy of orofacial myofunctional therapy (OMT) alone for SAOB subjects.MethodsEighteen adolescents with SAOB (4 males, 14 females; age: 12–18 years) and eighteen adolescents with normal occlusion (2 males, 16 females; age: 12–18 years) were selected. The electromyographic activity (EMGA) associated with mastication and closed mouth state was measured. Lateral cephalography was used to evaluate craniofacial morphology. Wilcoxon signed rank tests and t-tests were performed to evaluate myofunctional and morphological differences. Pearson or Spearman correlation analysis was used to investigate the correlations between EMGA and morphological characteristics. SAOB subjects were given OMT for 3 months, and the EMGA was compared between before and after OMT.ResultsDuring rest, anterior temporalis activity (TAA) and mentalis muscle activity (MEA) increased in SAOB subjects, but TAA and masseter muscle activity (MMA) decreased in the intercuspal position (ICP); and upper orbicularis activity (UOA) and MEA significantly increased during lip sealing and swallowing (P < 0.05). Morphological evaluation revealed increases in the FMA, GoGn-SN, ANS-Me, N-Me, L1-MP, U6-PP, and L6-MP and decreases in the angle of the axis of the upper and lower central incisors and OB in SAOB subjects (P < 0.05). TAA, MMA and anterior digastric activity (DAA) in the ICP were negatively correlated with vertical height and positively correlated to incisor protrusion. MEA was positively correlated with vertical height and negatively correlated with incisor protrusion; and the UOA showed a similar correlation in ICP, during sealing lip and swallowing. After SAOB subjects received OMT, MEA during rest and TAA, MMA and DAA in the ICP increased, while UOA and MEA decreased (P < 0.05).ConclusionSAOB subjects showed abnormal OMS features including aberrant swallowing patterns and weak masticatory muscles, which were interrelated with the craniofacial dysmorphology features including a greater anterior facial height and incisor protrusion. Furthermore, OMT contributes to OMS harmonization, indicating its therapeutic prospect in SAOB.

Vertical stability of different orthognathic treatments for correcting skeletal anterior open bite: a systematic review and meta-analysis.

Several orthognathic procedures have been applied to correct skeletal anterior open bites (SAOB). Which method is most stable has been debated and no consensus has been reached and there is no conclusive evidence for clinicians to use. To analyse whether maxillary, mandibular, or bimaxillary surgery provides a better stability. A systematic search was conducted up to December 2020 using PubMed, EMBASE, Medline, Scopus, Web of Science, Cochrane CENTRAL, and Google Scholar. We made direct comparisons among the controlled trials and also made indirect comparisons via subgroup analysis on the aspects of occlusional, skeletal, and dento-alveolar stability to assess the overall stability of each method. Finally 16 cohort studies were identified. At the occlusional level, pooled change in overbite was 0.21 mm in maxillary surgery, 0.37 mm in bimaxillary surgery, and -0.32 mm in mandibular surgery. At the skeletal level, pooled sella-nasion-Point A angle (SNA) was -0.12 degrees in bimaxillary surgery, -0.37 degrees in maxillary surgery and -0.20 degrees in mandibular surgery. The sella-nasion to palatal plane angle (SNPP) relapsed to a statistically significant degree in all samples received single maxillary surgery. Relapse of the sella-nasion-Point B angle (SNB) was 0.47 degrees in mandibular setback, -1.8 degrees in mandibular advancement, and -0.48 degrees in maxillary surgery. The Sella-Nasion to mandibular plane angle (SNMP) relapsed more in procedures involving bilateral sagittal split osteotomy than in other procedures. As for dento-alveolar changes, intrusion of molars and extrusion of incisors took place in most patients. Bimaxillary surgery produced the most beneficial post-operative increase in overbite, maxillary surgery led to a lesser but still positive overbite change, and mandibular surgery correlated with some extent of relapse. Skeletally, bimaxillary surgery was more stable than maxillary surgery at both SNA and SNPP; SNB was more stable in mandibular setback than advancement; and SNMP was unstable in both mandibular and bimaxillary surgeries versus maxillary surgery with comparable surgical changes. Dento-alveolar compensation helped maintain a positive overbite. CRD42020198088.

Evaluation of the facial soft tissue changes in skeletal anterior open bite patients treated with rapid molar intruder appliance using cone beam computed tomography

Aim: The aim of this study was to evaluate the facial soft tissue changes in skeletal anterior open bite patients treated with rapid molar intruder appliance using cone beam computed tomography (CBCT). Materials and Methods: This retrospective study included 2 groups. The first treatment group included randomly selected CBCT scans of 20 skeletal open bite patients (8 males and 12 females, mean age 11.6±1.1 years) who were treated with the rapid molar intruder appliance (RMI) for molar intrusion. The CBCT scans were taken before treatment (T1) and after open bite correction (T2). The facial soft tissue changes in the treatment group were compared with a closely matched second untreated control group with normal anterior overbite (9 males and 11 females, mean age 11.9± 1.2 years). Results: The first group showed significantly greater decreases in the angle of facial convexity and the H angle than the second group. The first group showed significantly greater increases in the lower lip protrusion and the soft tissue chin prominence than the second group. The upper lip protrusion and the soft tissue facial height were decreased in the first group and increased in the second one. The difference was statistically significant. The nasolabial angle was increased in the first group and decreased in the second one. The difference was statistically significant. Conclusions: Molar intrusion using the rapid molar intruder appliance (RMI) could result in significant improvement in the facial soft tissue profile in skeletal anterior open bite patients.

Relations between anterior disc displacement and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle.

In this study we investigated the relation between anterior disc displacement (ADD) and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle. Thirty female patients (60 joints) with both conditions were evaluated. Magnetic resonance imaging of the temporomandibular joint (TMJ) was used to diagnose both ADD and changes to the mandibular condyle (erosion, osteophyte, and deformity). The relations among ADD, changes to the mandibular condyle, and maxillomandibular morphology were examined statistically. Changes to the mandibular condyle had a higher score than sym anterior open bite, the deviated side in asymmetric anterior open bite, and the non-deviated side. The score for disc displacement on the non-deviated side was lower than both the sym side and the deviated side. Unilateral changes to the mandibular condyle and unilateral disc displacement were not apparent in sym anterior open bite, but a unilateral non-displaced disc was seen only on the asymmetric side. Mandibular condylar changes were significantly more common on the deviated, than on the non-deviated, side. The SNB angle was significantly smaller, and the ANB, GZN, and SN-mandibular plane angles were significantly larger in sym anterior open bite. Overjet, ANB angle, GZN angle, and SN-MP angle were significantly larger, and the SNB angle was significantly smaller, in the presence of ADD without reduction and mandibular condylar deformity. We conclude that the prevalence of ADD without reduction and changes to the mandibular condyle were related to mandibular asymmetry and mandibular morphology in anterior open bite. This retrospective study suggests that ADD without reduction and mandibular condylar bone changes may be related to the progression of skeletal class II open bite and mandibular asymmetry in cases of skeletal open bite.

Genetic And Environmental Factors Involved In The Development Of Oral Malformations Such As Cleft Lip/Palate In Non-Syndromic Patients And Open Bite Malocclusion

Among the most common malformations observed in the oral cavity are cleft lip/palate and malocclusions, being this last one considered by the World Health Organization, the third public health problem.Malocclusions include the anterior open bite, a change in the vertical plane, that can be of two types: dental anterior open bite and skeletal anterior open bite. Cleft lip and cleft palate are the most common congenital malformations at birth. These malformations result from a failure in the normal craniofacial development process, which requires the coordination of a complex series of events. From the embryological point of view, the cleft lip/palate is a consequence of the failure of the first superior branchial arch to complete fusion with the frontonasal process during pregnancy.All these malformations result from the interaction of both genetic and environmental factors. Among the environmental factors involved in the development of malocclusions are deleterious habits, mouth breathing and trauma. Several genes involved in the development of facial bones, muscles and teeth are also responsible for the development of malocclusions. In the same way, clefts development is a multifactorial trait where multiple genes are involved as well as environmental factor like alcohol consumption, tobacco, exposure to pesticides or toxic solvents, in a complex interaction.All these factors may jeopardize the normal functioning of the stomatognathic system and the consequent quality of life of the patient. The purpose of this study was to review the literature concerning the genetic and environmental aspects involved in the development of these malformations.

Dilemma in closing the bite: a case of orthognathic surgery

This case report demonstrates treatment of an open bite case with a history of trauma to the maxillary anterior region in childhood. A 20-year-old adult male presented with a convex profile and significant anterior bite and unilateral posterior crossbite. Surgical bite correction was planned but posed a dilemma in the choice of surgery. CPD/Clinical Relevance: To demonstrate the outcome of a case of skeletal anterior open bite treated with orthognathic surgery.

EVALUATION OF THE TEMPOROMANDIBULAR JOINT OSSEOUS CHANGES IN PATIENTS WITH ANTERIOR OPEN BITE: A RETROSPECTIVE STUDY

<h3>Background</h3> The temporomandibular joint (TMJ) has an important role in different human functions, including speech, mastication, and breathing. It has been found that osseous changes in the TMJ may stem from skeletal deformities of the head and neck. <h3>Objective(s)</h3> The aim of this study was to evaluate osseous changes in the TMJs of patients with an anterior open bite skeletal deformity using cone beam computed tomography (CBCT). <h3>Study Design</h3> Thirty-two female patients with skeletal anterior open bite and 32 age-matched normal females (skeletal class I) were included in this study. CBCT images were retrieved from the archives. In the CBCT scans, the presence of condylar deformities, including erosion, sclerosis, flattening, and condylar osteophytes, in addition to shape of condyle head in the sagittal and coronal view, were recorded. Moreover, inclination and height of the articular eminence were measured. Data were analyzed in SPSS version 24 software (SPSS Inc., Chicago, IL), with a confidence interval of 95%. <h3>Results</h3> The frequency of condylar head and articular eminence erosion was significantly higher in patients with open bite in comparison with the normal group (<i>P</i> < .05). A significant association was observed between the condylar head shape and the presence of open bite deformity in the coronal view, with the number of angular condylar shape being higher than that in the normal group (<i>P</i> < .05). In addition, inclination and height of the articular eminence was significantly higher in the normal group in comparison with the open bite group (<i>P</i> < .05). <h3>Discussion/Conclusions</h3> According to the present findings, osseous changes in the TMJ exist in patients with anterior open bite skeletal deformity. It was found that the shape of condyle was related to the presence of skeletal anterior open bite.