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INTRODUCTION: Present Finite-element-method (FEM) study evaluates the stress distribution values at the Temporomandibular-Joint (TMJ) during en-masse retraction of the mandibular dentition using buccal shelf bone screws with varying magnitudes of forces. MATERIAL AND METHODS: Nine replicas of a pre-existing three-dimensional finite element model of the craniofacial skeleton and articular disc from Cone-Beam-Computed-Tomography (CBCT) data and Magnetic-Resonance-Imaging (MRI) data of a patient were used. Buccal shelf (BS) bone screws were inserted buccal to the mandibular second molar region. Forces of magnitudes 250 gm, 350 gm and 450 gm were applied through NiTi coil springs along with stainless-steel archwires of sizes 0.016 × 0.022-inch, 0.017 × 0.025-inch and 0.019 × 0.025-inch. RESULTS: On the articular disc, the maximum stress was observed at the inferior region and the inferior part of the anterior and posterior zone at all force levels. The stress on the articular disc and displacement of teeth increased with increase in force levels in all the 3 archwires. The maximum stress at the articular disc and displacement of teeth was observed for 450 gm force and the least for 250 gm force. No significant difference in the amount of displacement of teeth or the stresses produced at the articular disc was seen with increasing the size of the archwire. CONCLUSION: With the present FEM study, we can deduce that it is better to use forces of lower levels on patients with temporomandibular-disorders (TMD) so as to reduce the stresses produced at the TMJ to avoid worsening of the TMD condition.
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Trastornos de la Articulación Temporomandibular , Diente , Humanos , Dentición , Alambres para Ortodoncia , Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/cirugía , Tornillos Óseos , Análisis de Elementos FinitosRESUMEN
OBJECTIVE: To identify the best-suited cephalometric parameter for assessing the sagittal skeletal discrepancy in the Indian population. DESIGN: An in vitro, observational, single-blinded, retrospective study. SETTING: Department of Orthodontics and Dentofacial Orthopaedics. METHODS: A total of 94 lateral cephalograms were used in this study. The study involved one key person and two examiners. The key person collected the radiographs, coded, analysed and classified them into three groups (skeletal classes I, II and III). Subsequently, the coded radiographs were independently analysed by the two examiners. They classified the cases by matching a minimum of 6 out of 11 parameters. On completion of diagnosis by the examiners, the samples were decoded and matched with the original diagnosis given by the key person. The samples in which identification of a particular cephalometric parameter matched the original evaluation as given by the key person was regarded as correctly diagnosed. The number of correctly assessed cases was used to judge the diagnostic performance of all the parameters in all the cases. Cross-validation of the method was performed, and a diagnostic algorithm was developed for diagnosis. RESULTS: ß angle and Pi angle showed a positive predictive value of 1 in both skeletal class I and II cases. ANB angle, W angle and HBN angle showed a positive predictive value of 1 in skeletal class III cases. CONCLUSION: No single cephalometric parameter can independently be used to diagnose sagittal skeletal discrepancy in all cases. However, a conclusive diagnosis on the type of sagittal skeletal malocclusion can be made by using a simple and easy to use diagnostic algorithmic process having a combination of cephalometric parameters.
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Cefalometría , Heurística , Maloclusión de Angle Clase III , Maloclusión Clase II de Angle , Maloclusión Clase I de Angle , Cefalometría/métodos , Humanos , Maloclusión Clase I de Angle/diagnóstico , Maloclusión Clase II de Angle/diagnóstico , Maloclusión de Angle Clase III/diagnóstico , Estudios RetrospectivosRESUMEN
AIM AND OBJECTIVE: To predict and correlate mandibular growth pattern using palatoscopy (average, horizontal, and vertical). MATERIALS AND METHODS: This retrospective study includes 120 archived maxillary casts. One key person and two examiners performed the study; the key person was responsible for coding and collecting casts and radiographs, as well as calibration of the examiners. The key person divided the samples into three craniofacial growth pattern groups (average, horizontal, and vertical) based on Frankfort-mandibular plane angle (FMA), SN-GoGn, and facial axis angle and distributed them to the blinded examiners. Rugae were studied using a modified Thomas and Kotze classification system. After the analysis, the results were decoded and analyzed with the corresponding cephalometric radiographs. RESULTS: Multinomial logistic regression was employed to predict the mandibular growth patterns with the following independent variables: Forwardly directed rugae, number of divergent rugae, predominant shape circular, predominant shape curved, primary rugae, predominant shape wavy, number of convergent rugae, and horizontally directed rugae. CONCLUSION: Palatal rugae patterns predict the growth pattern of the mandible. CLINICAL SIGNIFICANCE: Considering the significant parameters and their correlation with mandibular growth pattern, prediction of mandibular growth patterns can be done noninvasively.
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Mandíbula , Paladar Duro , Cefalometría , Humanos , Mandíbula/diagnóstico por imagen , Maxilar , Estudios RetrospectivosRESUMEN
BACKGROUND: Healing unbinds a well choreographed array of cellular, physiologic, biochemical, and molecular processes directed toward restoring the integrity and functional capacity of the damaged structures. The rate and degree of healing vary among individuals but is greatest during the first few months or years after tooth loss. Evidence suggests that alveolar bone ridge resorption may be prevented, initially by reconstructive surgical techniques using several materials which are employed at the time of extraction. This droves to the development of bone substitutes materials such as hydroxyapatite, beta tricalcium phosphate (ß TCP), and bioactive glasses. These regenerative materials not only act as an osteoconductive scaffold but also interact with the surrounding tissues and impart an osseostimulatory effect. METHODS: Twenty adult patients who required bilateral removal of homologous tooth, were informed and described regarding post extraction socket grafting using ß TCP and CPS followed by covering with Collagen Membrane. Radiographic densitometry evaluation of postoperative visits of immediate; 1st month; 3rd month; and 6th month using orthopantomograph was done. RESULTS: The Karl Pearson's Correlation coefficient was used to determine the degree of bone density with adjacent bone preoperatively and postoperatively. The statistical evaluation, CPS was more superior to ß TCP, with a difference of 58.75 and P value showed more significance (<0.0001). CONCLUSION: This article evaluates radiographically quality and quantity of bone formation in the socket, following extraction and bone grafting using Calcium Phosphosilicate (CPS) and ß TCP, it is concluded that the two modalities of treatment were efficient in improving the clinical outcome parameters as well as showed comparable regenerative effects when used in the treatment of "socket grafting" while between them CPS more superior to ß TCP biomaterials by Osteogenic properties.
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A case report of trifid and aplastic condyle in a 26-year-old female has been discussed. A marked oval radiolucency in the head of right condyle and absence of left condyle was observed on a panoramic radiograph. Diagnosis of trifid condyle was established and confirmed using computed tomography. Magnetic resonance images showed degenerative changes of the disc.
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Dysgenetic polycystic disease (DPD) is a rare cystic lesion affecting mainly the parotid salivary glands with only 14 reported cases in English literature. DPD of parotids is more common in females, common in younger age group, mostly bilateral in occurrence and commonly affects the superficial lobe. Surgery is performed for symptomatic relief and cosmosis. We report a case of a unilateral DPD of the parotid gland with distinctive histopathology. Patient was treated by performing total parotidectomy with preservation of the facial nerve.
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OBJECTIVE: To assess the distribution pattern of Langerhans cells in oral lichen planus using adenosine triphosphatase (ATPase) histochemistry and to correlate this with the duration of symptoms. METHOD AND MATERIALS: Included were fresh unfixed tissues from previously untreated cases that were clinically and histologically diagnosed as oral lichen planus (n=18). Healthy oral mucosal tissues were used as controls (n=5). ATPase activity in the Langerhans cells from the tissue samples was assessed by enzyme histochemistry. RESULTS: The difference in the distribution pattern of Langerhans cells in the superficial and basal half of the epithelium in both the lesional and control tissue was significant (P<.001, Mann-Whitney U test). With an increase in duration of symptoms, the median migration of cells from superficial position to the basal half was significant (P=.001, Kruskal-Wallis test). A negative correlation (Pearson correlation coefficient) was seen between duration of symptoms and migration of cells. CONCLUSION: The initial increase in the number of Langerhans cells in the lesional tissues compared to controls suggests that these cells are critically required for both the initiation and progression of the mucosal immune response in oral lichen planus. Variation in their number and distribution bear clinical importance as objective assessment of long-standing lesions could be made with reference to treatment planning.
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Adenosina Trifosfatasas/análisis , Técnicas para Inmunoenzimas , Células de Langerhans/enzimología , Liquen Plano Oral/inmunología , Liquen Plano Oral/patología , Adulto , Estudios de Casos y Controles , Recuento de Células , Movimiento Celular , Distribución de Chi-Cuadrado , Femenino , Humanos , Células de Langerhans/patología , Masculino , Mucosa Bucal/inmunología , Mucosa Bucal/patología , Estadísticas no Paramétricas , Adulto JovenRESUMEN
Ectodermal dysplasias are a complex group of genetically determined disorders clinically characterized by congenital alterations of the structures derived from the ectoderm. Even though ectodermal dysplasia with partial anodontia is common, this condition with total anodontia is not. We describe features of hypohidrotic ectodermal dysplasia with complete anodontia in a 6-year-old boy. In order to improve esthetics, speech and mastication, the child was provided with upper and lower complete dentures.
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Anodoncia/etiología , Displasia Ectodermal Anhidrótica Tipo 1/complicaciones , Anodoncia/rehabilitación , Niño , Dentadura Completa Inferior , Dentadura Completa Superior , Estética Dental , Humanos , Masculino , Masticación/fisiología , Habla/fisiologíaRESUMEN
We aimed to establish a reliable method of localizing an impacted maxillary canine on the sole basis of assessment of a single panoramic radiograph, and to determine the validity and reproducibility of the method. Panoramic radiographs of 50 subjects with a total of 68 impacted canines were analysed. The Canine Incisor Index (CII), Canine Canine Index (CCI), control Canine Incisor Index (c-CII), Zone (apical, middle, coronal) and Sector (I, II, III, IV) were determined on digitized panoramic radiographs. Comparison of the CII and CCI values of labially or palatally impacted canines revealed a statistically significant difference (P < 0.05). Comparison of labial and central canine impactions revealed no relation to CII or CCI (P > 0.05). There was a significant difference between palatal and central canine impactions in relation to CII (P < 0.05), but no significant difference between the two with respect to CCI (P > 0.05). Correct prediction of palatal canine impactions by differential magnification on a panoramic radiograph is possible in 77% of cases. Vertical and horizontal restrictions have no value in recognition of labiolingual position of impacted maxillary canines. The panoramic radiograph cannot be used as a sole radiograph for reliable localization of impacted maxillary canines.
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Diente Canino/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Radiografía Panorámica/estadística & datos numéricos , Diente Impactado/diagnóstico por imagen , Adolescente , Adulto , Arco Dental/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Incisivo/diagnóstico por imagen , Masculino , Odontometría/métodos , Hueso Paladar/diagnóstico por imagen , Magnificación Radiográfica , Reproducibilidad de los Resultados , Corona del Diente/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Diente no Erupcionado/diagnóstico por imagen , Adulto JovenRESUMEN
The objectives of the study are to evaluate the relationship between common HIV-related oral lesions and absolute CD4+ count, age, gender, and medication used and to assess the sensitivity, specificity, positive and negative predictive value of oral manifestations for low absolute CD4+ counts. HIV-positive patients, 200, from south India were selected, whose absolute CD4+ counts were determined within 2 weeks of oral examination. Sociodemographic data was obtained using a structured questionnaire. Oral manifestations were diagnosed according to presumptive criteria of EEC-clearinghouse classification (1993). Four or more concurrent oral lesions were statistically significant with low CD4+ counts <200 cells/mm3 (P = 0.005). The highest and lowest mean CD4+ cell counts were seen in individuals with linear gingival erythema (LGE; 172.5 cells/mm(3)) and pseudomembranous candidiasis (PC; 87 cells/mm(3)), respectively. Smoking, age (<35 years), and males had a positive association with oral hairy leukoplakia (OHL; P < 0.05). Patients with CD4+ counts < 200 cells/mm(3) were associated with 15 times greater risk of PC and four times at greater risk for occurrence of any oral manifestation. Concurrent oral manifestations (>or=4) were good predictors (80-100%) of severe immune suppression. In most resource poor countries where facilities for undertaking CD4+ counts are not available, the presence of concurrent oral manifestations may be used as an indicator of deteriorating immune status.
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Recuento de Linfocito CD4 , Candidiasis Bucal/inmunología , Infecciones por VIH/inmunología , Tolerancia Inmunológica , Leucoplasia Vellosa/inmunología , Adolescente , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas , Antiinfecciosos/uso terapéutico , Candidiasis Bucal/complicaciones , Eritema/complicaciones , Eritema/inmunología , Femenino , Enfermedades de las Encías/complicaciones , Enfermedades de las Encías/inmunología , Infecciones por VIH/complicaciones , Humanos , India , Leucoplasia Vellosa/complicaciones , Modelos Logísticos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Factores Sexuales , Fumar , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Ellis-van Creveld (EvC) and Curry-Hall (CH) syndromes are rare syndromes that occur due to mutations of genes mapped to the chromosome 4p16 region. Hence, they both have few features that are common. The dental literature describing the oral manifestations and etiology of both syndromes is scarce. We report a case of a 7-year-old girl who appeared with features that are common to both syndromes, as well as with other features such as reduced cranial base flexure and toes of equal length with skeletal changes that have not been mentioned or described in earlier reports. The patient possibly represents a new syndromic entity that has not been reported until now. Further, we present a review of various other similar syndromes, such as various types of orofacial digital (OFD) syndrome and acrofacial dysostosis.
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Anomalías Múltiples/patología , Enanismo/patología , Prognatismo/patología , Anomalías Dentarias/patología , Cefalometría , Niño , Disostosis Craneofacial/patología , Diagnóstico Diferencial , Síndrome de Ellis-Van Creveld/patología , Femenino , Deformidades Congénitas del Pie/patología , Deformidades Congénitas de la Mano/patología , Humanos , Uñas Malformadas/patología , Síndromes Orofaciodigitales/patología , Base del Cráneo/anomalías , SíndromeRESUMEN
Impacted canines are not uncommon in clinical practice, but intraosseous movement of impacted canines crossing the midline (transmigration) is a rare phenomenon. We report 4 cases of mandibular canine transmigration to emphasize the need to supplement periapical radiographs with a panoramic radiographic examination in patients with over-retained deciduous canines or missing permanent canines.