Preliminary data regarding the influence of the COL1a1 rs2249492 polymorphism on the risk of malocclusion in the Romanian population

Malocclusion is a condition characterized by diverse phenotypic expression patterns, with a complex underlying genetic background. COL1a1 is one of the genes that has been previously associated with malocclusion, with one particular SNP, rs2249492 (C>G, C>T), having been linked with an increased risk of skeletal class II malocclusion. In this paper, making use of DNA sequencing and cephalometric measurements, we present preliminary data regarding the association between the rs2249492 SNP and the risk of malocclusion in the Romanian population, illustrated as continuous, rather than categorical phenotypes. The results show a tendency towards a Class II pattern determined by mandibular retrognathism, rather than maxillary prognathism among the individuals possessing the mutant allele. Subsequent studies on larger sample sizes should include statistical analysis focused on associations between the rs2249492 allele and continuous phenotypic variation inside, but not restricted to Class II malocclusion, in order to acquire a more detailed picture of the interaction between the polymorphism and this complex condition

RELATION BETWEEN SAGITTAL POSITION OF THE MANDIBLE AND PHARYNGEAL AIRWAY VOLUME IN ADULTS USING CONE BEAM COMPUTED TOMOGRAPHY

Introduction: Many authors have discussed the relationship between craniofacial morphology and pharyngeal airway spaces in different malocclusions and skeletal patterns. So the aim of this work was to study the relation between sagittal position of the mandible and pharyngeal airway volume in adults using CBCT. Materials And Methods:Twentyone CBCT radiographs were collected from the archive of Radiology Department at Suez Canal University and were divided into 3 groups according to the measured SNB angle. Group 1 normal mandibular position, group 2 retrognathic mandible and group 3 prognathic mandible. Dolphin 3D imaging software was used to measure the airway volume for all the radiographs. Nasopharyngeal, oropharyngeal, hypopharyngeal and total pharyngeal airway volumes were measured for all the radiographs. F-test (ANOVA) was used for comparison between groups and Tukey test for pairwise comparisons. Correlations between variables were tested using PearsonÂ’s correlation coefficient. Results: there was statistically significant difference in the mean total pharyngeal airway volume and oropharyngeal airway volumes between the three groups. Nasopharyngeal airway volume and hypopharyngeal airway volume had non-significant difference between groups. There was a significant positive correlation between total pharyngeal airway volume (mm3) and SNB angle. Conclusion: Pharyngeal airway volume differs with different sagittal positions of the mandible. Pharyngeal airway volume decreases with mandibular retrognathism and increases with mandibular prognathism.

Parathyroid hormone Gene and Genes Involved in the Maintenance of Vitamin D Levels Association with Mandibular Retrognathism

In this study we evaluated whether single nucleotide polymorphisms (SNPs) in the genes encoding PTH, VDR, CYP24A1, and CYP27B1 were associated with mandibular retrognathism (MR). Samples from biologically-unrelated Brazilian patients receiving orthodontic treatment were included in this study. Pre-orthodontic lateral cephalograms were used to determine the phenotype. Patients with a retrognathic mandible were selected as cases and those with an orthognathic mandible were selected as controls. Genomic DNA was used for genotyping analysis of SNPs in PTH (rs694, rs6256, and rs307247), VDR (rs7975232), CYP24A1 (rs464653), and CYP27B1 (rs927650). Chi-squared or Fisher’s tests were used to compare genotype and allele distribution among groups. Haplotype analysis was performed for the SNPs in PTH. The established alpha was p < 0.05. Multifactor dimensionality reduction (MDR) was used to identify SNP–SNP interactions. A total of 48 (22 males and 26 females) MR and 43 (17 males and 26 females) controls were included. The linear mandibular and the angular measurements were statistically different between MR and controls (p < 0.05). In the genotype and allele distribution analysis, the SNPs rs694, rs307247, and rs464653 were associated with MR (p < 0.05). MDR analyses predicted the best interaction model for MR was rs694–rs927650, followed by rs307247–rs464653–rs927650. Some haplotypes in the PTH gene presented statistical significance. Our results suggest that SNPs in PTH, VDR, CYP24A1, and CYP27B1 genes are associated with the presence of mandibular retrognathism.

Genes Involved in the Maintenance of Vitamin D Levels Might Be Associated With Mandibular Retrognathism

: In this study we evaluated, if single nucleotide polymorphisms (SNPs) in the genes encoding PTH, VDR, CYP24A1 and CYP27B1 are associated with Mandibular Retrognathism (MR). Samples from biologically-unrelated patients receiving orthodontic treatment were included in this study. Pre-orthodontic lateral cephalograms were used to determine the phenotype. Patients having a retrognathic mandible (SNB&lt;78&ordm;) were selected as cases and those with an orthognathic mandible (SNB=78&ordm;&ndash;82&ordm;) were selected as controls. Genomic DNA was used for genotyping analysis of SNPs in PTH (rs694, rs6256 and rs307247), VDR (rs7975232), CYP24A1 (rs464653) and CYP27B1 (rs927650). Chi-squared or Fisher&rsquo;s tests were used to compare genotype and allele distribution among groups. Haplotype analysis was performed for the SNPs in PTH. The established alpha was p&lt;0.05. Multifactor dimensionality reduction (MDR) was used to identify SNP-SNP interactions. A total of 48 MR and 43 controls were included. In the genotype and allele distribution analysis, the SNPs rs694, rs307247 and rs464653 in were associated with MR (p&lt;0.05). MDR analyses predicted the best interaction model for MR was rs694-rs927650, followed by rs307247-rs464653-rs927650. Some haplotypes in the PTH gene presented statistical significance. Our results suggest that SNPs in PTH, VDR, CYP24A1 and CYP27B1 genes are associated with the presence of mandibular retrognathism.

Reestruturação do terço inferior da face com ácido hialurônico

The search for a harmonious and balanced face grows more and more and the demand for aesthetic treatments increases in the same proportion. Procedures that use hyaluronic acid as a filling material have high acceptance and rapid postoperative recovery, bringing excellent results. This article reports the clinical case of a young male patient, Pattern II, according Capelozza, due to mandibular retrognathism, whose main complaint was the recessed position of the chin. Restructuring with highly cross-linked hyaluronic acid in the affected region has been suggested. The remodeling of the chin together with its increase in volume through the application of hyaluronic acid was able to significantly improve the profile and the complaint-neckline of the patient.

Mandibular orthopedic advancement in different facial patterns and distinct stages of skeletal maturation

ABSTRACT The Herbst appliance can be very effective in treatment of Class II patients with mandibular retrognathism. Because of the continuous action in a full-time basis, treatment time using it normally takes from six to ten months, and is usually followed by a second phase of full fixed appliances, in order to obtain both occlusal refinement and long term stability. Despite Herbst appliance’s effectiveness in the occlusal and dentoalveolar perspectives, its facial results may differ among patients with different growth patterns, as well as in distinct stages of skeletal maturation. In the current paper, two patients with different facial patterns are presented, who were treated under the same protocol, using Herbst and full fixed appliances in different skeletal maturation stages, and both dentoalveolar and facial results are compared and discussed.

DENTOSKELETAL, SOFT TISSUE AND AIRWAY EFFECTS OF THE ADVANSYNC2 IN PATIENTS WITH CLASS II DIV 1 MANDIBULAR RETROGNATHISM: A RETROSPECTIVE STUDY

Objective: To evaluate dentoskeletal, soft tissue and airway changes in Class II malocclusion patients treated with AdvanSync2 Class II corrector in conjunction with fixed appliances. Methods: Forty-five subjects with skeletal and dental Class II malocclusion requiring fixed functional therapy were included. Pre-treatment cephalograms served as control group (Group 1), post treatment cephalograms of patients treated using AdvanSync2, as experimental group (Group 2). Changes in skeletal, dental, soft tissue profile and airway were analyzed on lateral cephalograms using 21 variables from multiple cephalometric analysis. Results were tabulated and data was analyzed using Wilcoxon signed rank test for linear parameters and paired student t test for angular parameters. Results: Maxillary skeletal and dental effects included restriction of growth, upper incisor retrusion and retroclination at p<0.001. Mandibular incisors proclined during treatment. Forward mandibular relocation was noted, though not statistically significant. Upper and lower lip repositioning was achieved, establishing lip competency. Changes in Z angle and nasolabial angle were positive, reducing facial convexity. Significant airway dimensional improvements were noted. Conclusion: AdvanSync2 Class II corrector was effective in treating skeletal Class II malocclusions with mandibular retrognathism. It produced its effects mainly through maxillary restriction and mandibular dentoalveolar changes which furthermore helped in achieving good soft tissue profiles in patients. Positive airway changes were also noted.

Interpositional arthroplasty with temporalis myofascial flap reconstruction in a case of temporomandibular joint bony ankylosis: a case report and review of literature

The report describes the treatment of a 30 year old female patient having unilateral right temporomandibular joint (TMJ) bony ankylosis whose mouth opening was restricted to 5 mm and had additional mandibular retrognathism causing severe mastication problems besides speech difficulties and low morale. The ankylosis had resulted in facial asymmetry due to bony hard swelling in front of right tragus. The patient was taken up for right interpositional arthroplasty with temporalis myofascial flap reconstruction by pre auricular approach and left coronoidectomy by intraoral approach as a preferred technique. A satisfactory mouth opening of 33 mm was achieved in immediate post-operative. Patient was followed up with aggressive mouth opening exercises in postoperative period.