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1.
Artigo em Inglês | MEDLINE | ID: mdl-37771233

RESUMO

A dental implant with three distinct layers, of titanium alloy at core, porous titanium alloy at the intermediate layer and titanium alloy hydroxyapatite composite at the outer layer, is designed to achieve low elastic modulus and adequate strength with bioactive surface. Artificial Neural Network (ANN) along with Rule of Mixture (ROM) is used to generate the objective functions for the Genetic Algorithm (GA) based multi-objective optimization for achieving the optimal designs, which are validated using Finite Element Analysis (FEA) simulations. The composition and processing parameters are correlated with the yield strength and elastic modulus of titanium alloy using ANN. The ANN models are generated to express the strength and effective modulus of the implant using ROM. To determine the optimal composition of titanium alloys, porous layers, and composite layers for a three-layer dental implant, multi-objective genetic algorithm is employed. The Pareto optimal solutions provide the guidelines for designing the implant. A few selected non-dominated solutions are used for studying the actual stress distribution at the bone-implant interface using FEA, and showed significant improvements compared to conventional implants.


Assuntos
Implantes Dentários , Titânio , Ligas , Interface Osso-Implante , Informática , Análise de Elementos Finitos , Estresse Mecânico
2.
Head Face Med ; 19(1): 6, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882815

RESUMO

OBJECTIVE: To determine whether odontometric parameters using cone beam computed tomography (CBCT) would aid in sex estimation by assessing sexual dimorphism of odontometric parameters. MATERIAL AND METHODS: The focused question was whether there is sexual dimorphism in linear and volumetric odontometric parameters when assessed using CBCT. The preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines were followed to conduct a systematic search until June 2022 in all major databases. Data were extracted regarding the population, size of the sample, age range, teeth analyzed, linear or volumetric measurements, accuracy, and conclusion. The quality of included studies was assessed using (Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. RESULTS: Out of the 3761 studies identified, twenty-nine full-text articles were assessed for eligibility. Finally, twenty-three articles (4215 participants) that provided data on odontometrics using CBCT were included in this systematic review. The odontological sex estimation were assessed either linear measurements (n = 13) or volumetric measurements (n = 8) or both (n = 2). Canines were analysed in maximum number of reports (n = 14), followed by incisors (n = 11), molars(n = 10) and premolars(n = 6). Most of the reports (n = 18) confirmed the existence of sexual dimorphism in odontometric parameters when assessed using CBCT. No significant differences in odontometrics between the sexes were noted in some reports (n = 5). The accuracy of sex estimation was assessed in eight investigations, which ranged from 47.8 to 92.3%. CONCLUSIONS: Odontometrics of human permanent dentition using CBCT exhibit a certain degree of sexual dimorphism. Both linear and volumetric measurements of teeth can aid sex estimation.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Caracteres Sexuais , Humanos , Bases de Dados Factuais , Incisivo , Dente Molar
3.
Contemp Clin Dent ; 14(4): 289-292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38344155

RESUMO

Aim and Objectives: Estimation and correlation of plasma fibrinogen degradation product (FDP) and salivary fibrin precipitating factor (FPF) in oral sub mucous fibrosis (OSMF) patients, betel quid chewers without OSMF and healthy individuals. The study aims to evaluate whether FDP and FPF can be used as a marker for development and progression of OSMF and whether there is any correlation between the two. Methodology: The study included 163 subjects grouped into three categories, Group 1, which included 54 control patients, Group 2, which included 55 betel quid chewers, and Group 3, which included 54 clinically confirmed OSMF patients. All of them were subjected to the estimation of plasma FDP and salivary FPF. Results: FDP was present in 52 (96.3%) patients in Group 3, 2 (3.6%) patients in Group 2, and 1 patient in Group 1 (1.9%). FPF was positive in eight patients. The correlation of FDP and FPF was done by Fisher's exact test and was found to be statistically nonsignificant. Conclusion: In the present study, FDP was positive in 52 (96.3%) OSMF patients; hence, FDP may be used as an early indicator of OSMF. FDP was found to be positive in two patients with a habit of chewing betel quid without OSMF. It may be hypothesized that these patients are more likely to develop OSMF. Hence, the estimation of FDP may be used as a diagnostic test to predict an impending OSMF before it could manifest itself clinically. FPF was negative in some OSMF patients, may be because it is below the detectable range.

4.
J Exp Ther Oncol ; 13(1): 59-63, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30658029

RESUMO

BACKGROUND: Risk factors such as chronic use of tobacco, smoking and alcohol consumption of individual's lifestyle may possibly influence the significant role in the etiopathogenesis of precancerous lesions (PL) and Conditions (PC) and lead to oral cancer. Previous studies have revealed that genetic factors have contributed to a remarkable extent in the development of this chronic disease. Limited studies have confirmed that ABO blood groups remain reportedly possible genetic factor to the specific disease such as oral malignant. In this context, we have reported that individuals in a particular blood group are more prone to develop lesions and certain types of cancer. This has thrown a light to take up an effort to conduct this present study. MATERIALS AND METHODS: The present study covering 105 patients and grouped into three subjects with 35 participants in each. a) oral squamous cell carcinoma b) oral leukoplakia and c) submucous fibrosis. Gender and age group impact was also made to understand the interaction between the focused sample groups. A separate control was gathered from a same geographical population composed of gender-matched healthy volunteers. Slide agglutination was employed for blood grouping and results were tabulated for statistical analysis. RESULTS: Blood group "A" exhibited a significant relationship between oral squamous cell carcinoma patient and odd ratio shown 1.74 times higher risk of developing oral cancer. Gender different and habit stimulation have increased the risk. A significant relationship was observed between ABO blood group and oral leukoplakia and oral submucous fibrosis. CONCLUSION: Study inferred that blood group "A" is found to be at the high risk in developing oral malignant syndrome due to its susceptibility, whereas oral pre-cancer is hypothesized that individual habits are the host risk factor and transformed to carcinoma by interacting genetic factors to act upon ABO blood group.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Neoplasias Bucais , Fibrose Oral Submucosa , Lesões Pré-Cancerosas , Humanos , Leucoplasia Oral , Neoplasias Bucais/etiologia , Fibrose Oral Submucosa/etiologia , Lesões Pré-Cancerosas/etiologia , Fatores de Risco , Síndrome
5.
Asian Pac J Cancer Prev ; 16(17): 7497-500, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26625751

RESUMO

BACKGROUND: Tumor markers, designated as a broad group of substances produced by malignancies, could be in the form of biochemical substances, immunological substances, cell surface changes and genetic alterations. Cancer, a disorder of cellular behavior is characterized by alteration of serum glycoproteins. L-fucose, a hexose, which is the terminal sugar in most of the plasma glycoproteins, may be useful as a tumor marker for the detection, monitoring and prognostic assessment of malignancies. The aim of the study was to ascertain the role of serum fucose as a biomarker for early detection of oral cancer and to compare serum fucose levels in healthy controls, leukoplakia and oral cancer patients. MATERIALS AND METHODS: The study included 60 (100.0%) subjects, who were grouped as 20 (33.3%) control subjects, 20 (33.3%) squamous cell carcinoma patients and 20 (33.3%) leukoplakia patients. Fucose estimation was done using UV-visible spectrophotometry based on the method as adopted by Winzler using cysteine reagent. The results were analyzed statistically using ANOVA with Bonferroni post hoc tests. RESULTS: Results showed a high significance in serum fucose in oral squamous cell carcinoma (OSCC) and leukoplakia subjects compared to normal controls. There was a gradual increase in the values noted from control to leukoplakia and to squamous cell carcinoma. CONCLUSIONS: Estimation of serum fucose may be a reliable marker and can be used as an effective diagnostic biomarker in oral squamous cell carcinoma patients.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Fucose/sangue , Neoplasias de Cabeça e Pescoço/sangue , Leucoplasia/sangue , Neoplasias Bucais/sangue , Adulto , Carcinoma de Células Escamosas/diagnóstico , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Leucoplasia/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço
6.
Case Rep Dent ; 2013: 370695, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23431477

RESUMO

Hypoglossia-hypodactyly is a rare congenital anomaly affecting the tongue and the limbs. Hall in 1971 classified it under a complex group of disorders called oromandibular limb hypogenesis syndromes. It is an extremely rare condition with around 40 cases reported in the world literature. The cause of the syndrome is unknown. Some type of intrauterine trauma is the most widely accepted etiology. The characteristic features of the syndrome are hypoglossia, limb anomalies of variable degree, and micrognathia of the mandible. This unique case report of hypoglossia-hypodactyly was observed in a patient with normal mandible. In addition, patient also had pulmonary regurgitation. His parents and other siblings were normal. Positive prenatal history of maternal hyperthermia was obtained suspecting it to be the cause of the syndrome.

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