The Impact of the COVID-19 Pandemic on Orthodontic Adult Patients' Characteristics and Decision on Orthodontic Appliance.

Purpose: There is an overall paucity of data examining the specific details of orthodontic patients' patterns or orthodontic service disruptions possibly influenced by COVID-19 pandemic. Therefore, this study aimed to explore the impact of the COVID-19 pandemic on orthodontic clinic disruption regarding the change in adult patients' characteristics and decisions of orthodontic treatment devices. Patients and Methods: A retrospective sample of 311 patients receiving orthodontic treatment from 2018 to 2022 were collected and divided into two groups: before (n = 167) and during (n = 144) the COVID-19 pandemic. Demographics, dental indices, the index of complexity outcome and need (ICON), and the degree of treatment difficulty were analyzed. Results: There were fewer students among patients during the COVID-19 pandemic than before (24.5% versus 35.9%, P = 0.036). Compared with patients before the pandemic, more patients selected ceramic brackets or Invisalign during the pandemic (P = 0.022). There were higher percentage of class I dental malocclusions among patients during than before the COVID-19 pandemic (P = 0.044). Moreover, the ICON score and the score of the degree of treatment difficulty were both significantly lower for patients during than before the COVID-19 pandemic (63.9±14.0 versus 58.3±15.3, P=0.001 and 7.4±2.6 versus 6.8±2.6, P=0.049, respectively). Conclusion: The COVID-19 pandemic influenced the characteristics and decisions of orthodontic patients. Those who still came to the orthodontic clinic despite the COVID-19 outbreak may have been those with less malocclusion severity and treatment difficulty. Besides, during the time of covid-19 pandemic, more patients chose ceramic bracket and Invisalign as their orthodontic treatment device rather than conventional or self-ligating metal brackets.

Robotic Archwire Bending in Orthodontics: A Review of the Literature.

Malocclusion is a widespread oral health issue that adversely affects individuals' health and well-being. Currently, fixed orthodontics is considered the most efficient treatment for correcting malocclusion, with archwire bending playing a key role in orthodontic treatment. Traditionally, orthodontists manually performed archwire bending using various handheld pliers and other mechanical tools, requiring a significant amount of time, precision, and specialized training yet being unable to guarantee appliance accuracy. The process of shaping orthodontic wire is challenging due to its high stiffness and superelasticity, resulting in a time-consuming, laborious process that is prone to human errors. With advancements in orthodontics, traditional methods have taken a backseat, making way for innovative technologies that provide more accurate and personalized treatment options. The continuous efforts to enhance treatment efficiency, accuracy, efficacy, and patient experience have led to the integration of robotics into various orthodontic procedures. The use of robotics in archwire bending represents a breakthrough in orthodontics, offering unparalleled precision, consistency, and efficiency. This technology reduces treatment time and patient discomfort, overcoming the limitations of manual bending and enhancing orthodontic treatment overall. Hence, the present study aims to review the literature on robotic archwire bending in orthodontics, including their drawbacks and their impact on orthodontic treatment.

Enhancing Orthodontic Renewal and Retention Techniques: A Systematic Review.

Orthodontists have a variety of options available for retainers. Research in Orthodontics focuses on assessing outcomes important to clinicians; however, there is inconsistency in how these outcomes are selected and evaluated. This review sought to assess the effects of different orthodontic retainers on patients' quality of life (QoL). Various approaches were employed in this systematic review, and a thorough search was conducted across six databases. The review involved a comprehensive evaluation of six included studies, highlighting changes in dental structure post-treatment, emphasizing the role of extraction procedures and the quality of debonding in improving retention. The study identified key outcomes for orthodontic clinical trials, highlighting orthodontists' preferences for specific retainer types. Moreover, it discussed the impact of sociocultural influences on retention care. Involving patients actively in discussions about whether to end or extend the retention phase was deemed essential. Noteworthy improvements in occlusal outcomes were linked to extraction treatments. Gender and malocclusion severity influenced QoL before and after orthodontic treatment. The degree of improvement observed in the Class III malocclusion group was comparatively lower than that in the Class I and Class II groups. Orthodontic treatment was found to yield favorable psychological outcomes, as evidenced by notable enhancements in self-esteem and social engagement among individuals. Fixed appliances were shown to negatively affect oral health-related quality of life (OHRQoL), particularly for those with aesthetic and functional concerns. A consensus has been reached on the essential themes and outcomes that should be incorporated in clinical trials related to orthodontic retention for non-cleft and non-surgical cases.

Correlation Between Horizontal and Vertical Skeletal Components in Dental Malocclusions Among the Jazan Population.

INTRODUCTION: The dentoskeletal morphology of various malocclusions has been analyzed in cephalometric studies. It is important to understand the vertical and horizontal components of orthodontic treatment. To provide accurate treatment, an orthodontist needs to understand the facial types of an individual. This study aims to evaluate a correlation between vertical and horizontal components of skeletal and dental malocclusion by assessing cephalometric radiographs of the population of Jazan province. METHODS: The cephalometric radiographs of 267 eligible participants were assessed digitally. Fourteen skeletal and dental parameters were used to evaluate the association. Reliability was checked with the intra-class coefficient. Statistical analyses included descriptive statistics and Spearman's rho test. Statistical significance was set at P ≤ 0.05. RESULTS: Correlations were found between anterior facial height (AFH), posterior facial height (PFH), FH ratio (Jarabak ratio), upper incisor to NA (U1-NA), lower incisor to NB (L1-NB), and upper incisor to the palatal plane (U1/PP). In dental class I, AFH (N-Me) had a strong positive correlation with L1-NB (0.300), U1/PP (0.164), and L1/MP (0.215). In dental class II, AFH negatively correlated with U1-NA (-0.735) and positively correlated with L1-NB (0.292), L1/MP (0.085), and U1-NA. PFH (S-Go) positively correlated with L1-NB (0.525) in class I but negatively correlated in class II. However, a negative relation was observed between all the vertical and horizontal components in class III. CONCLUSION: This study suggests potential associations between vertical and horizontal components in developing skeletal and dental discrepancies.

Orthodontics and Temporomandibular Disorders: An Overview.

The relationship between orthodontics and temporomandibular disorders (TMDs) constitutes a subject of paramount significance in dental and craniofacial health. This abstract embarks upon an in-depth examination of the intricate connection between orthodontic practices and TMD, primarily focusing on evaluating the impact of orthodontic treatment modalities on the health and functionality of the temporomandibular joint (TMJ). This exploration elucidates the multifaceted interplay between orthodontic interventions and TMD by traversing a landscape of scholarly research and empirical investigations. The review draws from a broad spectrum of studies to analyze the potential influence of orthodontic treatments, which encompass occlusal adjustments and alterations in jaw positioning, on the development and management of TMD symptoms. The inquiry delves into the diverse range of TMD conditions, considering the implications of orthodontic techniques on occlusal stability, condylar alignment, and overall TMJ function. Through a comprehensive synthesis of the available body of knowledge, this abstract aspires to equip dental practitioners, orthodontists, and researchers with a nuanced understanding of the complex dynamics that govern the relationship between orthodontics and TMD. This knowledge, in turn, offers a foundation for informed clinical decision-making and the formulation of effective treatment strategies for patients presenting with TMD symptoms. By shedding light on the intricate interactions between orthodontic procedures and TMJ health, this abstract contributes to the advancement of clinical practices, promoting improved patient outcomes and well-being in the context of both orthodontics and TMDs.

Dental Malocclusion in Mixed Dentition Children and Its Relation to Podal System and Gait Parameters.

BACKGROUND: Dental malocclusion is an increasingly frequent stomatognathic disorder in children and adolescents nowadays. The purpose of this study was to confirm or deny the correlations between body posture and malocclusion. METHODS: In the study, gait, distribution of foot pressure on the ground, and body balance were examined. The research group consisted of 76 patients aged 12-15 years. The research group was obtained from patients attending periodic dental check-ups at Healthcare Center Your Health EL who agreed to participate in the study. The patients were divided into two groups without malocclusion and with malocclusion, using Angle classification, which enabled determination of the anteroposterior relationship of the first molars. The pedobarographic mat was used to analyze the distribution of foot forces on the ground, the diagnostic system Wiva® Science was used for gait analysis, and Kineod 3D was used for posture analysis. The Shapiro-Wilk test used for analysis showed inconsistency with normal distribution for all measurement parameters. The Mann-Whitney U test was used for the analysis, and the significance level was set at p ≤ 0.05. RESULTS: Examination of the relationship between stabilometric and gait parameters showed that the position of the mandible in relation to maxilla has an important effect on gait rhythm, gait cycle duration, and right step duration time. Patients diagnosed with malocclusion showed high-speed walking rhythm in comparison to patients with Angle's class I (p = 0.010). The duration of the whole gait cycle (p = 0.007) and the duration of right step (p = 0.027) were prolonged in students without orthodontic disorders compared to the other. CONCLUSIONS: The conducted study proved that there is correlation between the presence of a stomatognathic disorder and gait cycle parameters. There is a statistically noticeable correspondence between the position of the mandible in relation to maxilla and walking rhythm, gait cycle duration, and right step duration time. Namely, students who presented malocclusion had a high-speed walking rhythm and decreased duration of the gait cycle and of the right step. On the other hand, students without disorders (Angle's class I) showed low-speed rhythm and increased duration of the gait cycle and of the right step in comparison to Angle's classes II and III.

Clinical Characteristics of Patients with Dental Malocclusion: An Otolaryngologic Perspective.

Purpose: Allergic rhinitis (AR), which is a major cause of upper airway obstruction, may affect the development of the dental malocclusion. This retrospective study was aimed to investigate association between AR and dental malocclusion in otolaryngologic perspectives. Methods: Patients (n = 217) referred to the otolaryngology department before initiating orthodontic treatment were recruited. The frequency and severity of AR symptoms, sinonasal outcome test (SNOT-22) scores, physical examination findings, acoustic rhinometry results, and treatment modalities were retrospectively assessed. Patients with positive skin prick test findings (SPT) (n = 173; orthodontic group) were compared with age- and sex-matched patients being treated for AR (AR group). Results: We found that 76.5% of the enrolled patients had subjective nasal symptoms, and 93.1% patients showed abnormal physical examination findings such as inferior turbinate hypertrophy (82.0%), adenotonsillar hypertrophy (31.8%), or deviated nasal septum (7.4%). The 173 (79.7%) patients with positive SPT results exhibited a significantly higher incidence of rhinorrhoea, sneezing, and inferior turbinate hypertrophy compared to those with negative SPT results. The proportion of patients who underwent pharmacological or surgical treatments was significantly higher among patients with nasal obstruction (92.0%) than among patients without nasal obstruction (36.9%). The frequency and mean visual analogue symptom scores for nasal obstruction, rhinorrhoea, and sneezing, as well as all SNOT-22 domain scores, were significantly higher in the AR group than in the orthodontic group. The minimal cross-sectional area measured with acoustic rhinometry showed no significant difference between groups. Conclusion: Patients with dental malocclusion had a high SPT (+) rate and a high prevalence of structural abnormalities of the upper airway. The early detection and treatment of subclinical AR, other rhinological problems, and structural abnormalities of the upper airway in patients with malocclusion may help us manage malocclusion from an otolaryngologic perspective.

Unilateral Condylar Hyperplasia With Active Bony Overgrowth: A Case Report.

Condylar hyperplasia (CH) is an overgrowth disorder of the temporomandibular joint bones caused by growth center overactivity of the mandibular condyle. Although the disorder is mostly idiopathic, several etiologies have been proposed. CH presents as progressive facial asymmetry with functional abnormalities. A combination of clinical, histopathological, and radiological findings is crucial to determine the diagnosis. Several diagnostic algorithms have been described in the literature. Management of CH is variable and depends on the growth of the bone. Here, we present the case of a 36-year-old female who presented with progressive facial asymmetry which was diagnosed as unilateral CH with active bony overgrowth.

Risk of dental malocclusion in children with upper respiratory tract disorders: A case-control study of a nationwide, population-based health claim database.

OBJECTIVES: The aim of this study was to evaluate the association between different upper respiratory tract disorders and severe dental malocclusion in pediatric patients. METHODS: Newly diagnosed patients (N = 773) with dental malocclusion aged 8-18 years and controls (N = 3865) were identified from the health claim records of the Longitudinal Health Insurance Database 2000 of Taiwan's National Health Insurance Research Database. Controls were frequency matched to the cases by sex, age group, and index year. Univariate and multiple logistic regression analyses were used to evaluate the association between severe dental malocclusion and six common upper respiratory tract disorders, including acute sinusitis, allergic rhinitis, chronic sinusitis, nasal septum deviation, nasal polyps, and hypertrophy of tonsil and adenoids. RESULTS: The risk of severe dental malocclusion was significantly elevated in pediatric patients with three upper respiratory tract disorders, including acute sinusitis (adjusted odds ratio [aOR] = 1.66, 95% confidence interval [95% CI] 1.39-1.99), allergic rhinitis (aOR = 1.64, 95% CI 1.34-2.02), and chronic sinusitis (aOR = 2.01, 95% CI 1.27-3.19). When all the six upper respiratory tract disorders were simultaneously included in the multiple logistic regression analysis, acute sinusitis (aOR = 1.48, p < 0.001) and allergic rhinitis (aOR = 1.34, p < 0.010) were significantly and independently associated with an increased risk of severe dental malocclusion. CONCLUSIONS: Findings from this nationwide, population-based case-control study indicated that acute sinusitis and allergic rhinitis were independently and significantly associated with an increased risk of severe dental malocclusion in pediatric patients. Pediatricians should remain vigilant for the risk of dental malocclusion in their patients with these disorders.

Cephalometric Study of the Overjet Development in Warmblood Foals.

Class II malocclusion is the most frequently occurring congenital malocclusion in horses. Radiographic cephalometric procedures adopted from human dentistry were used to study the development of overjet in a population of 650 Warmblood foals. Thirteen foals were diagnosed with measurable overjet at the beginning of the study. The malocclusion in nine foals resolved spontaneously and four foals without overjet at 2 weeks of age developed the condition during the first year of life. A cephalostat used in human orthodontics to immobilize the patient's head while being radiographed was replaced by a researcher-made head-holding device, whose size was based on the results of a pilot study. Laterolateral digital radiographs of each foal's head (cephalograms) were taken at five time points until the age of 12 months. Thirteen cephalometric points were identified and nine distances were measured on each radiograph. Additionally, the angle between the long axis of the upper and lower incisors was evaluated. Cephalometric measurements proved to be useful to identify foals that showed spontaneous regression of the malocclusion over the study time between 9 and 16 weeks of age.

Heritability of teeth angulation and inclination in patients with overt malocclusion.

PURPOSE: To use 3-dimensional cone beam computed tomography (CBCT) images obtained on patients before treatment with dental malocclusion to calculate the heritability estimates of full-tooth angulation and inclination. A heritability estimate is a number between zero and one indicating the percentage of genetic factors involved in determining the phenotypic variation observed. METHOD: CBCT images of 111 patients (51 sibships) were analysed measuring both tooth angulation and inclination using the Anatomage Invivo5 software for central incisor to second molar. The long axis of each tooth was defined and traced as the cusp tip of the most mesiobuccal cusp to 6mm coronal to the apex of the mesiobuccal root. SPSS statistical software was used to analyse the data and calculate the heritability estimates for each tooth type in the maxilla and in the mandible regardless of the side. RESULTS: Teeth inclination showed higher heritability estimates than tooth angulation. Furthermore, maxillary teeth showed higher heritability estimates than mandibular teeth and anterior teeth showed higher heritability than posterior teeth. CONCLUSION: Genetic effect was more evident on tooth inclination than tooth angulation, on anterior teeth more than posterior teeth, and on maxillary teeth more than mandibular teeth.

Dental occlusion and body balance: A question of environmental constraints?

BACKGROUND: In the past few years, growing interest was given to the relationship between the dental occlusion and the body balance. While most research focused on this relationship at static conditions, it is evident that the contribution of the sensory information for balance control is different depending on the environmental constraints. RESEARCH QUESTION: The aim of the present paper was to elucidate whether the stomatognathic system (SS) contributes differently on body balance regulation according to the presence of external disturbances. METHODS: Literature regarding the different sources involved in the proprioceptive information to the SS was reviewed. The influence of dental occlusion on balance control at different external environments was then explored. RESULTS: The main findings are: (a) a plausible evidence between the masticatory and cervical muscles can be described; (b) a reciprocal connection between the trigeminal and vestibular nuclei supports the influence of the SS on body balance; (c) traditionally, research involving the relationship between the SS and balance control has focused on strictly controlled situations, thus, ignoring the sensory reweighting which occurs depending on the external disturbances; and (d) the afferences of dental occlusion for balance control seem strengthened when more difficult conditions are present. CONCLUSION: Results of the present review suggest that afferent signals from dental occlusion effectively contribute to balance control when more external perturbations are present, that is unstable support surface, fatigue and tasks being performed. However, more studies are needed to elucidate the mechanisms by which dental occlusion may influence balance control focusing on different external environments.

[Dental malocclusion in children: warning signs]. / Troubles de l'articulé dentaire chez l'enfant : les signes d'alerte.

DENTAL MALOCCLUSION IN CHILDREN: WARNING SIGNS. Dental malocclusions are common, and can be dental, skeletal and/or functional. Detecting these pathologies earlier is a signal to remove these causing factors, and act in favor of an harmonious growth of the jaws and the face. The dental alert signs include abnormalities of shapes, numbers, positions and eruption delay. Arch length discrepancy is due to a problem of teeth positions on the arch, resulting in overlaps or in interdental spaces. Dento-skeletal abnormalities are also to be analysed in the three space dimensions: the sagittal direction looks for a jaw too much projected forward or backward, the vertical and transverse directions evaluate mainly the recovery of the upper on the lower teeth and the absence of a narrow maxilla. The functional examination aims to check the stop of sucking habit after 3 years old, the ability of a good nasal breathing and a good swallowing. These disorders, in addition to the aesthetic consequences, lead primarily to temporomandibular joint disorders, masticatory and digestive disorders, ventilatory and obstructive sleep apnea, and dental and periodontal problems. These disorders are mainly fixed by the growth potential of the child, functional rehabilitation or using orthopedics or orthodontics appliances.

TROUBLES DE L'ARTICULÉ DENTAIRE CHEZ L'ENFANT : LES SIGNES D'ALERTE. Les troubles de l'articulé dentaire sont fréquents, ils peuvent être dentaires, squelettiques et/ou fonctionnels. Dépister tôt ces pathologies permet d'agir pour supprimer ces facteurs responsables, et favoriser une croissance harmonieuse des mâchoires et de la face. Les signes d'alerte dentaires comportent les anomalies de forme, de nombre, de position et de retard d'éruption. La dysharmonie dentomaxillaire correspond à un problème de place des dents sur l'arcade, se traduisant par des chevauchements ou à l'inverse des espaces interdentaires. Les anomalies dentosquelettiques sont aussi à analyser dans les trois dimensions de l'espace : sur le sens sagittal on recherche une mâchoire trop projetée vers l'avant ou l'arrière, dans les sens vertical et transversal on évalue principalement le recouvrement des dents supérieures sur les inférieures et l'absence de palais étroit. L'examen des fonctions vérifie l'arrêt de la succion après 3 ans, la capacité d'une bonne respiration nasale et d'une bonne déglutition. Ces troubles, en plus des conséquences esthétiques, entraînent des désordres temporomandibulaires, masticatoires et digestifs, ventilatoires et des apnées obstructives du sommeil, ainsi que des problèmes dentaires et parodontaux. Ils se corrigent principalement grâce au potentiel de croissance de l'enfant, par la rééducation fonctionnelle ou à l'aide d'appareils orthopédiques ou orthodontiques.

Prevention of Injury-Induced Osteoarthritis in Rodent Temporomandibular Joint by Targeting Chondrocyte CaSR.

Traumatic joint injuries produce osteoarthritic cartilage manifesting accelerated chondrocyte terminal differentiation and matrix degradation via unknown cellular and molecular mechanisms. Here we report the ability of biomechanical stress to increase expression of the calcium-sensing receptor (CaSR), a pivotal driver of chondrocyte terminal differentiation, in cultured chondrogenic cells subjected to fluid flow shear stress (FFSS) and in chondrocytes of rodent temporomandibular joint (TMJ) cartilage subjected to unilateral anterior cross-bite (UAC). In cultured ATDC5 cells or TMJ chondrocytes, FFSS induced Ca2+ loading and CaSR localization in endoplasmic reticulum (ER), casually accelerating cell differentiation that could be abrogated by emptying ER Ca2+ stores or CaSR knockdown. Likewise, acute chondrocyte-specific Casr knockout (KO) prevented the UAC-induced acceleration of chondrocyte terminal differentiation and matrix degradation in TMJ cartilage in mice. More importantly, local injections of CaSR antagonist, NPS2143, replicated the effects of Casr KO in preventing the development of osteoarthritic phenotypes in TMJ cartilage of the UAC-treated rats. Our study revealed a novel pathological action of CaSR in development of osteoarthritic cartilage due to aberrant mechanical stimuli and supports a therapeutic potential of calcilytics in preventing osteoarthritis in temporomandibular joints by targeting the CaSR. © 2018 American Society for Bone and Mineral Research.

Assessment of dental maturation on orthopantomograms among children with various dental malocclusions at a tertiary care hospital.

OBJECTIVE: To determine and compare the median dental age among males and females and in subjects with dental Class I, II and III malocclusions. METHODS: The retrospective study was conducted at Aga Khan University Hospital and comprised dental records of patients from July to December 2016 who were aged 9-16 years and had complete dentition excluding third molars. The sample was divided according to dental malocclusion which was further categorised according to chronological age groups. SPSS 21 was used for data analysis. RESULTS: Of the 270 sbjects whose radiographs were studied, 135(50%) each were males and females. Children aged 11-12 years showed a statistically significant difference (p=0.03) in the median dental age among genders. There was a strong positive correlation in the dental and chronological ages in the males (p<0.001) and females (p<0.001) sample. Median time of eruption of mandibular second permanent molar in different malocclusions was 11 years and 2 months. CONCLUSIONS: There was a strong positive correlation between chronological and dental ages for males and females. Females subjects were dentally advanced compared to the male subjects aged 11-12 years. ..

Prevalence of Malocclusion in Permanent Dentition of Iranian Population: A Review Article.

BACKGROUND: The aim of this study was systematic review and meta-analysis of prevalence in current and relevant literature about this developmental disorder to present the profile of malocclusion in Iran. METHODS: This review study was carried out with systematically identified and critically assessed studies reporting malocclusion prevalence among Iranian population in permanent dentition. National and international databases were searched for articles about prevalence of malocclusion by Angle classification in different regions of Iran from 1994 to 2015. After applying inclusion and exclusion criteria, the quality of articles was checked by professional checklist. Data extraction and meta-analysis was performed. A random-effect model was employed. Publication bias was checked. RESULTS: Of 2768 articles, 21 cases were included. The pooled prevalence of malocclusion was about 87% (95% CI: 78.3-92.2) in Iranian population; however, the prevalence of malocclusion across individual studies varied considerably (ranging from 23.7% to 99.7%). Prevalence of normal occlusion, class I, II and III malocclusion were reported as 13.3% (CI 95%: 7.8-21.7), 50.7% (CI 95%: 42.9-58.4), 21% (CI 95%: 17.5-25.1), 5.5% (CI 95%: 3-10); respectively. Maximum prevalence of malocclusion was in the East of Iran. CONCLUSION: The results showed a high prevalence of malocclusion in Iranian population. The baseline information could be appropriately utilized for the future planning to meet the orthodontic treatment need among the Iranian population.

Genetic Polymorphism in MMP9 May Be Associated With Anterior Open Bite in Children

Abstract Anterior open bite (AOB) has a multifactorial etiology caused by the interaction of sucking habits and genetic factors. The aim of this study was to evaluate the association between AOB and polymorphisms in genes that encode Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Four hundred and seventy-two children that presented at least one sucking habit were evaluated. Children were examined clinically for the presence of AOB. Genomic DNA was extracted from saliva. Genotyping of the selected polymorphisms in MMP2, MMP3, MMP9, TIMP1 and TIMP2 was carried out by real-time PCR using the TaqMan method. Allele and genotype frequencies were compared between the groups with and without AOB using the PLINK® software in a free and in a recessive model using a chi-square test. Logistic regression analysis was implemented (p≤0.05). Two hundred nineteen children had AOB while 253 did not. The polymorphism rs17576 in MMP9 was significantly associated with AOB (p=0.009). In a recessive model GG genotype was a protective factor for AOB (p=0.014; OR 4.6, 95%CI 1.3-16.2). In the logistic regression analysis, none of the genes was associated with AOB. In conclusion, the polymorphism rs17576 (glutamine for arginine substitution) in MMP9 was a protective factor for AOB.

Resumo A mordida aberta anterior apresenta uma etiologia multifatorial causada pela interação entre hábitos de sucção e fatores genéticos. O objetivo deste estudo foi avaliar a associação entre mordida aberta anterior e polimorfismo nos genes que codificam as metaloproteinases da matriz (MMPs) e seus inibidores teciduais (TIMPs). Foram avaliadas 472 crianças que apresentvam pelo menos um hábito de sucção. As crianças foram clinicamente examinadas para avaliar a presença de mordida aberta anterior. DNA genômico foi extraído da saliva. A genotipagem dos polimorfismos selecionados em MMP2, MMP3, MMP9, TIMP1 e TIMP2 foi realizada por PCR em tempo real, usando o método de TaqMan. As frequências alélicas e genotípicas foram comparadas entre os grupos com e sem mordida aberta anterior usando o software PLINK®. Duzentas e dezenove crianças apresentavam mordida aberta anterior enquanto 253 não a apresentavam. O polimorfismo rs17576 em MMP9 estava significativamente associado com mordida aberta anterior (p=0,009). No modelo recessivo (GG versus AG+AA) o genótipo GG foi um fator protetor para mordida aberta anterior (p=0,014; OR 4,6; 95%CI 1,3- 16,2). Concluindo, o polimorfismo rs17576 (substituição de glutamina por arginina) em MMP9 está associado com mordida aberta anterior. Os resultados obtidos suportam a hipótese de que fatores genéticos estão envolvidos com a etiologia da mordida aberta anterior.

GH-secreting pituitary macroadenoma (acromegaly) associated with progressive dental malocclusion and refractory CPAP treatment.

BACKGROUND: A link between progressive dental malocclusion, the use of a continuous positive airway pressure mask and GH-secreting pituitary macroadenoma (acromegaly) has not been previously reported. The present clinicopathological analysis stresses that tooth malposition should not be seen exclusively as a local process. CASE PRESENTATION: A 62-year-old caucasian man with no relevant medical history reported difficulty chewing food and perceived voice alteration during his annual periodontal check-up. He also referred stiffness of the tongue, face, and submandibular area. The patient had been diagnosed with obstructive sleep apnea syndrome two years previously, since when he had worn a continuous positive airway pressure device during sleep. Exploration of the occlusion revealed significant changes: an atypical left lateral and anterior open bite with major buccoversion of teeth 33, 34, 35, 36. Inspection of the soft tissue revealed only macroglossia, although external palpation indicated a subcutaneous stiffness of the submandibular area. General analytical tests, including hormone profiles, and magnetic resonance imaging confirmed the diagnosis of acromegaly induced by a pituitary adenoma. Intrasellar tumor resection via transsphenoidal approach was performed. After surgery, the patient already noted a marked improvement of all symptoms associated with the acromegaly. Desaturation data also evolved favourably and the pulmonologist advised the patient to abandon the continuous positive airway pressure treatment. CONCLUSION: Progressive dental malocclusion may be associated with a systemic disease and the use of a nasal mask with premaxillary support may distort the diagnosis of acromegaly.

Dental Angle class asymmetry and temporomandibular disorders.

OBJECTIVES: The aim of this study was to determine whether there is an association between the presence of asymmetric molar or canine Angle classes on the two sides and the presence of temporomandibular joint dysfunction (TMD). MATERIALS AND METHODS: Participants to the study were divided into two groups: TMD group (90 patients) or a control group (58 patients). In the TMD group, clinical assessment for TMD was performed according to the Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guidelines by the same two trained examiners. In both groups, all subjects underwent an assessment of dental occlusion, focusing on the assessment of bilateral canine and molar Angle class relationship. The study protocol was reviewed and approved by the Institutional Review Board of the University of Padova, and each participant gave written consent to take part in the investigation. RESULTS: TMJ pain was diagnosed in 58, disk displacement in 96, arthrosis in 17, and muscle pain in 46 individuals. Molar Angle class was symmetrical in 86 individuals and asymmetrical in 62 subjects. Molar Angle class was not correlated with any of the TMD diagnoses. Canine Angle class was correlated with TMJ arthrosis. Correlation values with the other TMD diagnoses were low and were not significant. CONCLUSIONS: It can be suggested that an association between dental Angle class asymmetry and TMDs does not exist and that the role of dental asymmetries as a factor correlated with the presence of TMD signs and symptoms is minimal.

Prevalence of ponticulus posticus among patients with different dental malocclusions by digital lateral cephalogram: a comparative study.

PURPOSE: The aim of the present study was to investigate the prevalence of ponticulus posticus among patients with dental Angle class I, II, and III malocclusions in Middle Anatolian population. METHODS: A total of 1246 cephalometric radiographs were examined in a 6 months period. Each patient was assigned an identification number, and demographic information, absence/presence of PP, if present, type of PP and type of dental malocclusion were recorded by two observers. In cases where there was any disagreement, a third observer was consulted. Distributions of obtained values were analysed using Pearson's Chi-square test. RESULTS: The mean age of subjects was 20.98 ± 6.95 years (range 10-39). In the analysed sample, PP had a prevalence of 18.8 % (complete form 9.6 %, incomplete form 9.2 %). There was a significant difference between genders (p = 0.002) (more prevalent in male patients: 119/522; 23 %). No significant difference was found between age groups (p > 0.05). PP was most frequently detected in Angle class III patients (78/351; 22.2 %) but there was no significant difference between malocclusion groups (p > 0.05). CONCLUSION: In the present study, PP is found to be a relatively common anomaly in patients with dental malocclusions. Although Angle class III patients showed a higher frequency of PP, statistically no significant difference was found among dental malocclusion groups.