Tamil Nadu Government Dental College and Hospital

In circumstances where identification of an individual by fingerprint or dental record comparison is difficult, palatal rugae may be considered as an alternative source of comparative material. This article evaluates the use of palatal rugae patterns for forensic identification with an indigenously developed computer software program. Comprehensive computerized antemortem records were constructed for 250 subjects and a comparison matching process performed using both recorded and unrecorded samples. The efficiency of this computer-based identification method was then assessed. The program proved to have an average sensitivity of 0.93 and specificity of 1 and had a success rate of 92-97% in matches with digitized rugae pattern samples.

The most challenging situations in Forensic Odonto-Stomatology are mass disasters, where the forensic dentist is usually confronted with charred human remains or heavily decomposed or fragmented bodies. This article determines the extent of preservation of palatal rugae for use as an alternative identification tool in such situations, using a study group comprising burn victims and cadavers simulating forensic cases of incineration and decomposition. The thermal effects and the decomposition changes on the palatal rugae of burn victims with panfacial third degree burns and human cadavers in storage were respectively assessed and graded on a new scale. Ninety three percent of burn victims and 77% of human cadavers had Grade 0 changes (normal). When changes were noted, they were less pronounced than the generalized body involvement of burns in burn victims and the generalized body decomposition of human cadavers.

Native fluorescence characteristics of blood plasma were studied in the visible spectral region, at two different excitation wavelengths, 405 and 420 nm, to discriminate patients with different stages of oral malignancy from healthy subjects. The fluorescence spectra of blood plasma of oral malignant subjects exhibit characteristic spectral differences with respect to normal subjects. Different ratios were calculated using the fluorescence intensity values at those emission wavelengths that give characteristic spectral features of each group of experimental subjects studied. These fluorescence intensity ratios were used as input variables for a multiple linear discriminant analysis across different groups. Leave-one out cross-validation was used to check the reliability of each discriminant analysis performed. The discriminant analysis performed across normal and oral cancerous subjects classified 94.7% of the original grouped cases and 93.7% of the cross-validated grouped cases. A classification algorithm was developed on the basis of the score of the discriminant functions (discriminant score) resulted in the analyses. The diagnostic potentiality of the present technique was also estimated in the discrimination of malignant subjects from normal and nonmalignant diseased subjects such as liver diseases. In the discriminant analysis performed across the three groups, normal, oral malignancy (including early and advanced stages) and liver diseases, 99% of the original grouped cases and 95.9% of the cross-validated grouped cases were correctly classified. Similar analysis performed across normal, early stage of oral malignancy, advanced oral malignancy and liver diseases correctly classified 94.9% of the original grouped cases and 91.8% of the cross-validated grouped cases.

BACKGROUND/PURPOSE: Oral lichen planus is an autoimmune disorder that has posed a challenge in spite of the several treatment modalities available. Here, we have proposed yet another treatment modality, photodynamic therapy, for this condition. The aim of the study was to treat patients having symptomatic oral lichen planus with photodynamic therapy with methylene blue as photosensitizer. METHODS: Twenty patients with symptomatic oral lichen planus were included in the study. They were treated with 5% methylene blue mediated photodynamic therapy (light source: Xenon arc lamp, wavelength: 630 ± 5 nm, total dose: 120 J/cm(2) per sitting) in four sessions (1st, 4th, 7th and 15th day). Follow-up was done on second and fourth week after the therapy. RESULTS: There was significant improvement in signs and symptoms of the lesion at first and second follow-up visits (P-value<0.001). CONCLUSION: There was satisfactory reduction in signs and symptoms of oral lichen planus without any side effects. Thus, methylene blue mediated photodynamic therapy seems to be a promising alternative for the control of oral lichen planus.

AIM: Oral cancer is a major health concern in many parts of the world. Despite its low survival rates, when detected early or in the precancer stage, it can drastically increase the survival rates. This strongly supports the need for sensitive biomarkers to perk up early detection of oral cancers. The aim of the study is to estimate whether salivary interleukin-6 (IL-6) can be used as a molecular marker to diagnose leukoplakia and oral squamous cell carcinoma (OSCC). METHODS: The sample of 75 cases was divided into three groups of 25 patients each: group I: oral leukoplakia; group II: OSCC; group III: control group. Saliva samples were collected by simple drooling method and the concentration of IL-6 was determined by using ELISA (enzyme-linked immunosorbent assay) technique. RESULTS: When the concentration of salivary IL-6 among the three groups was compared, the results were statistically significant ("P" value <0.001). CONCLUSION: The increase in salivary IL-6 in leukoplakia and OSCC might point out its local production by the tumor cells. The difference in its levels between these two lesions might indicate the progression of precancer to cancer. Further longitudinal studies with increased sample size are needed to substantiate the utility of salivary IL-6 as diagnostic or prognostic marker for oral cancer and precancer.

Tongue squamous cell carcinoma (TSCC) generally affects the older age group exposed to tobacco for an extended period. However, recent research points out that there is an increased incidence of TSCC in the younger age group without any traditional risk factors making TSCC as a distinct biological entity in this group. This study aims to assess the prevalence and risk factors of tongue carcinoma in the younger group of patients. This article included studies that addressed the TSCC involving young patients and that which are PubMed indexed. Initially, 390 articles were considered; but after refined evaluation, 123 articles had their titles and abstracts matching to this present work. After the extraction of the case reports, review articles and the articles without the assessment of the parameter of harmful habits, we have included only 23 articles in the sample matching the title. The statistical analysis was formed by using chi-square tests using IBM SPSS ver. 20.0. The cohort of the younger population in these studies was mostly in the 35- to the 45-year age group. The majority of reports (64%) classified the patients below 40 years of age as a young group. Though male predominance is reported to be 55%, female patients are also more affected (40%) in the younger age group compared with, the more typical and usual group of head and neck carcinoma patients. TSCC in older adults predominantly reported in tobacco users (70%) whereas in young adults, TSCC was associated with a higher incidence in nonsmokers (53%); the causes of these cancers in young adults remain unclear. The identification of the potential risk factors aside from traditional factors is vital to control the incidence of TSCC in young patients.

BACKGROUND: This randomized, double-blind, parallel arm study was carried out to evaluate and compare the effectiveness between nano-hydroxyapatite (HAP) and a benchmark dentifrice in reducing dentin hypersensitivity. MATERIALS AND METHODS: About 36 patients were selected, randomly divided into two groups and was evaluated clinically using three different stimuli, i.e., tactile, air blast, and cold water test. The patient's responses to various stimuli were recorded using a visual analog scale at baseline and after 4 weeks. RESULTS: Statistical analysis was done using unpaired and paired t-tests. It was seen that patients treated in both groups showed significant reductions scores across all sensitivity measures at the end of 4 weeks. CONCLUSION: The HAP containing toothpaste was effective in reducing dentin hypersensitivity with pre-existing benchmark toothpaste tested and hence can be advocated in the management of hypersensitivity.

Idiopathic thrombocytopenic purpura (ITP) is defined as a hematologic disorder, characterized by isolated thrombocytopenia without a clinically apparent cause. The major causes of accelerated platelet consumption include immune thrombocytopenia, decreased bone marrow production, and increased splenic sequestration. The clinical presentation may be acute with severe bleeding, or insidious with slow development with mild or no symptoms. The initial laboratory tests useful at the first visit to predict future diagnosis were erythrocyte count, leukocyte count, anti-glycoprotein IIb/IIIa antibodies, reticulated platelets, plasma thrombopoietin level. Treatment should be restricted to those patients with moderate or severe thrombocytopenia who are bleeding or at risk of bleeding. We present a case report on ITP with clinical presentation, diagnosis and management.

Obstructive sleep apnea syndrome (OSAS) is a potentially serious disorder attacking millions of people around the world. Many of these individuals are undiagnosed, and even though diagnosed often exhibit a poor compliance with the use of continuous positive airway pressure at nights, a very effective nonsurgical treatment. A variety of surgical procedures have been proposed to manage and treat OSA. This article throws insights into assessing the sites of obstruction and a number of surgical procedures designed to address OSA. The scope of this article is to provide information to dentists which enables them to identify the patients who have OSAS and to guide these patients in making informed decisions regarding treatment options.

Mucormycosis is an opportunistic fungal infection that is caused by normally saprobic organism of the class Zygomycetes. The main form of mucormycosis are pulmonary and rhinocerebral. Rhinocerebral mycormycosis typically starts in the maxillary antrum, particularly in poorly controlled diabetics. Invasion of surrounding tissue can cause necrotizing ulceration of palate with a blackish slough and exposure of bone. A case of mucormycosis presenting as palatal performation is discussed in this article.

AIM: To compare the fracture resistance of teeth restored with fiber-reinforced composite (FRC) posts and experimental dentin posts milled from human root dentin. MATERIALS AND METHODS: Thirty maxillary central incisors were divided into three groups of ten each. Twenty teeth were restored with FRC posts and solid dentin posts and numbered as Groups 2 and 3 respectively while Group 1 acted as the control, without any post. The teeth were loaded at 135° angle to their long axes after core build-up and the failure loads were recorded. RESULTS: One-way Analysis of Variance (ANOVA) and Bonferroni multiple comparisons revealed a significant difference among test groups with the control group showing the highest fracture resistance, followed by the dentin post group and lastly the FRC post group. CONCLUSIONS: Teeth restored with dentin posts exhibited better fracture resistance than those restored with FRC posts.

AIM OF THE STUDY: Oral leukoplakia (OL) is the most common potentially malignant disorder that may transform into oral carcinoma. By treating leukoplakia in its incipient stage, the risk of occurrence of oral carcinoma can be prevented. In this aspect, photodynamic therapy (PDT) can serve as a useful treatment modality. The aim of the study is to treat patients with OL using PDT in which 5-aminolevulinic acid (ALA) is used as a photosensitizer. MATERIALS AND METHODS: Five patients with OL were included in the study. They were treated with 10% ALA mediated PDT (light source: Xenon lamp, power: 0.1 W, wavelength: 630 ± 5 nm, total dose: 100 J/cm(2) per session) for 6-8 sessions. Follow-up was done for a period of 1 year. RESULTS: One month (4 weeks) after ALA-PDT, the response was evaluated based on clinical examination. It was as follows: Complete response: Two patients; partial response: Two patients; and no response: One patient. There was no recurrence in any of the cases. CONCLUSION: There was satisfactory reduction in the size of the OL lesion without any side-effects. Thus, ALA mediated PDT seems to be a promising alternative for the treatment of OL.

Historical Background X-rays were discovered in 1895 by Wilhelm Roentgen. Digital radiology has overtaken conventional screen-film radiography since it was introduced in the mid-1980s.[1] Digital imaging uses sensor of solid-state, and information is presented and stored as an image using a computer. The dawn of the digital era in dental radiography came in 1987 with the first digital radiography system called radio visio graphy (RVG), launched by Dr. Francis Mouyen. A physicist and charge-coupled device (CCD) image sensor design engineer Paul Suni created the CCD image sensor technology that made the RVG digital radiography system a reality.[2] Main factor distinguishing digital systems from conventional is their response to incident radiation. An imaging system operates between the range of a completely bright and a completely dark image. The dynamic range of digital detectors is about 400-fold compared to film-screen. Digital Radiography Digital radiographic images can be indirect, direct, or semi-direct. Radiographic produced by flatbed scanners with a transparency adapter, slide scanners, and digital cameras are referred to as indirect digital radiographs. Direct digital images are acquired using a solid-state sensor such as CCD or complementary metal–oxide–semiconductor (CMOS)-based chips. Semi-direct images are obtained using a phosphor plate system charge-coupling transfers the number of electrons deposited in each pixel from one well to the next in a sequential manner to a readout amplifier for image display on the monitor. Area digital sensor array is used for intraoral radiography while linear arrays are used in extraoral imaging. CMOS sensors use an active pixel technology. It reduces required system power by a factor of 100 and eliminates the need for charge transfer. Phosphor plate system consists of a polyester base coated with a crystalline emulsion of europium-activated barium fluorohalide Compound. Incident X-ray photons create a latent image. A scanner reads the image information by scanning the plate with a laser beam of near-red wavelengths to form digital image. Clinical Applications Contrast resolution is an important parameter in the diagnostic accuracy of caries detection. Software allows image manipulation by applying specific filters to detect carious lesions. For periodontal diagnosis, the high resolution of intraoral radiography helps the visualization of the bony supporting tissues, including small details such as periodontal ligament space, lamina dura, and bony trabecularization.[3] Digital imaging allows measuring bone loss extent using image analysis tools. High-resolution technology and/or dedicated endodontic filtering improves the visibility of small file tips as small as 0.06 mm. Serial radiographs with identical geometric projection and exposure settings can be subtracted using digital subtraction radiography. This allows for qualitative evaluation by underscoring small changes such as caries progression, periapical lesions, or even quantitative evaluation of periodontal bone loss.[4] Forensic dentistry uses radiology in determining the age of an individual by assessing the stage of eruption of teeth as well as for evidence in the identification of the suspect, to determine the cause of death, to find faulty charting of teeth, legal matters, body identification, postmortem examination, and for nonaccidental injuries of children and forensic anthropology.[5] In evaluating cysts or benign tumors, multiplanar sections (axial, coronal, and sagittal planes) are helpful to locate deeper tissues. It is also helpful in postsurgical follow-ups of lesions with high recurrences. Advantages Digital radiography requires 90% lesser dose compared to E-speed film. In digital imaging, image quality may be interactively manipulated after image acquisition, i.e., contrast, blur and noise may be altered digitally. Filtering of the digital image may result in a reduction of blur of structure boundaries. Diagnostic accuracy of the detection of carious lesions is increased by digital contrast enhancement and filtering. Measurements of length, angle, and area can be made on a digital image. Three-dimensional reconstruction of radiographic images is of importance for the diagnosis and treatment planning in malformations, trauma, tumor investigation, and surgery planning. Low-pass spatial filtering (smoothing) reduces the image noise. However, it decreases image resolution. High-pass spatial filtering (hardening) enhances edges to create a crisper image, but with more noise. It facilitates the detection of boundaries of low-contrast regions. In digital radiography, the same image can be used for various diagnostic purposes, for instance, marginal bone loss which requires lighter images and caries detection requiring darker images. With the CCD system, the image is displayed immediately postexposure. Although there is a lag time between scanning and the appearance of an image exists with the pressure-sensitive paint method, it is faster than the conventional method. Digital Imaging and Communications in Medicine (DICOM) standards encompass primary and secondary diagnostic images acquired digitally that provides a basis for interoperability of digital system's output.[6] DICOM standard facilitates a common method of transmission for medical radiographic images. DICOM compliant system utilizes common file formats that are universally recognized. For instance, when one is contemplating digital image submission to insurance companies.

OBJECTIVES: This study presents data on the prevalence and severity of dental fluorosis in 11-15-years-old school children of Kanyakumari district, TamilNadu, India, and also the relationships between prevalence of dental fluorosis and selected risk factors. MATERIALS AND METHODS: A total of 1800 children, from all the nine blocks of Kanyakumari district, studying in classes 6-10 were examined using type III examination. The assessment form designed specifically for this study was used while examining each student. RESULTS: Dental fluorosis was present in 15.8% (285 children) of the study population and the community fluorosis index was calculated to be 0.27. The prevalence of dental fluorosis varied from as low as 1.4% in some blocks to as high as 29.4% in some others. There was a significant difference in the level of dental fluorosis between rural and urban residents ( P < 0.001). The prevalence of dental fluorosis was higher in children who consumed pipe water as compared to children who consumed ground water. 65% of the children with dental fluorosis had no caries, indicating the positive effects of fluoride. CONCLUSIONS: The prevalence of dental fluorosis can be attributed to the level of fluoride in the drinking water as it exhibited a step-wise increase when the water fluoride levels increased from 1.5-1.7 ppm. Measures for defluoridation of drinking water before distribution has to be taken in the high prevalence blocks to lower the burden of dental fluorosis in this community.

PURPOSE: Osseointegration being an accepted and well-documented concept, attention is now directed towards simplification of the mechanical design of implants and towards achieving biomechanical success. The aim of this literature review is to provide an overview of the one-piece implant, with its advantages and disadvantages over a conventional two-piece implant. METHODS: The PubMed database was searched in the English language using the keywords one-piece implant, single-piece implant, single-stage implant surgery, and two-piece implant. Articles were selected on the basis of whether they had sufficient information related to placement timing, surgical procedure used, loading protocol, follow-up periods, marginal bone loss, and implant success rates of one-piece implants. For inclusion, a study group must have had a minimum of 30 one-piece implants followed for at least 1 year. DISCUSSION: Nineteen articles were subjected to the selection criteria. Out of 19 clinical trials only 11 met the selection criteria. Five parameters were taken into consideration for studying one-piece implants: placement timing, surgical technique, loading protocol, marginal bone loss, and implant survival rate. The data from the identified studies were tabulated according to these parameters and discussed. CONCLUSION: Delayed placement of one-piece implants is more commonly practiced than extraction and immediate placement. Most surgeons prefer surgeries using flaps as compared to flapless surgeries, and in most cases, one-piece implants were loaded immediately. Limited literature reveals both positive and negative results regarding the effect of a one-piece implant system on surrounding hard and soft tissues.

The aim was to evaluate the design parameters of dental implants shape, diameter and length on stress distribution by finite element analysis (FEA).The objectives of the study was to compare the influence of stress distribution in the implants of screw-vent tapered and parallel design by varying the implant diameter with a standard implant length. Six dental implant models have been simulated three-dimensionally. The influence of diameter and length on stress distribution was evaluated by Group I: for screw-vent tapered design (Zimmer Dental Implant Carlsbad, CA, USA) (1) Dental implant model with diameter 3.7 mm and length 13 mm. (2) Dental implant model with diameter 4.1 mm and length 13 mm. (3) Dental implant model with diameter 4.7 mm and length 13 mm. Group II: for parallel design (Zimmer Dental Implant Carlsbad, CA, USA) (4) Dental implant model with diameter 3.7 mm and length 13 mm. (5) Dental implant model with diameter 4.1 mm and length 13 mm. (6) Dental implant model with diameter 4.7 mm and length 13 mm. The 3-D model of the implant was created in the pro-e wildfire 4.0 software by giving various commands. This model was imported to the ANSYS software through IGES (initial graphic exchange specification) file for further analysis. All six models were loaded with a force of 17.1, 114.6 and 23.4 N in a lingual, an axial and disto-mesial direction respectively, simulating average masticatory force in a natural oblique direction, to analyze the stress distribution on these implants. The increase in implant diameter in Group I and Group II from 3.7 to 4.1 mm and from 4.1 to 4.7 mm with constant 13 mm length for screw-vent tapered and parallel design implant resulted in a reduction in maximum value of Von Mises stress in the bone surrounding the implant was statistically significant at 5% level done by student "t" test. The overall maximum value of Von Mises stress was decreased in parallel design implant diameter of 4.7 mm with constant length of 13 mm when compared to screw-vent tapered design implant samples. The results of the FEA computation depend on many individual factors including material properties, boundary conditions interface definition and also on the overall approach to the model. The results depicted that the tapered shape implant design exhibited higher stress levels in bone than the parallel shaped implant design which seemed to be distributing stresses more evenly. The application of a 3-D model simulation with the non-symmetric loading by the masticatory force on a dental implant resulted in a more satisfactory modeling of "clinical reality" than that achieved with 2-D models used in other studies.

Periodontitis is a chronic bacterial infection resulting in destruction of the supporting structures of the teeth. Regeneration of the lost tissues has faced difficulties primarily due to the lack of support during the intricate healing processes. A surgical additive which can 'jump start' the healing process to a more predictable regenerative process is always on the wish list of any periodontist. Platelet-rich fibrin (PRF) is a second generation platelet concentrate that has been considered to be an important, easy to obtain, predictable surgical additive for periodontal regeneration. This autologous scaffold provides the much needed bio-chemical mediators which has the potential for enhancing reconstruction of the periodontium. This review article tries to understand as to why PRF would be an important link to reach predictable periodontal regeneration.

The mechanical properties of different polymer matrix composites are discussed in this research study. These composites are multiphase materials in which reinforcing elements and a polymer matrix are suitably combined. The mechanical properties of 18 PMCs, including nylon 66 reinforced with 5, 15, and 25% wt% silicon carbide (SiC) and nylon 66 reinforced with 5, 15, and 25% wt% boron carbide (B 4 C), were evaluated using an injection moulding technique at three different injection pressures in this study. The optimization of process parameters like reinforcement material, reinforcement quantity, and injection pressure to maximize the tensile and impact strength of nylon 66 composites are the main focus of this study. It is observed that the specimens 25% SiC with an injection pressure of 90 MPa has optimised tensile strength, while the specimen 5% B 4 C with an injection pressure of 90 MPa has optimised impact strength.

OBJECTIVE: The aim of this study was to investigate the neutralizer effect of antioxidant agents on the bond strength of bleached enamel. MATERIALS AND METHODS: Sixty enamel slabs were prepared from 60 freshly extracted maxillary central incisors and were divided into six groups. The negative control group received no bleaching treatment and the other groups were bleached with 35% carbamide peroxide (Opalescence Quick; Ultradent, South Jordan, USA). In Group II, composite was built immediately after bleaching and cured without any antioxidants. In Group III, bleached specimens received composite build ups delayed by 1 week. In Groups IV, V, and VI bleached specimens received applications of superoxide dismutase (SOD), sodium ascorbate (SA), and tocopherol solutions, respectively, for 10 min. Following composite bonding, the micro shear bond strength (μSBS) was measured at a speed of 1 mm/min in universal testing machine. STATISTICAL ANALYSIS USED: The μSBS values of all the groups were analyzed using the analysis of variance followed by Tukey honestly significant difference post-hoc test. RESULTS: Bonding of composites to unbleached group (Group I) exhibited the highest mean SBS values and among the antioxidant-treated groups, the highest SBS values were seen with SOD (Group IV) treated samples (23.0040 ± 4.30565 MPa). CONCLUSIONS: Application of SA, alpha-tocopherol, and SOD can effectively reverse the bond strength with bleached enamel. SOD gave a comparatively more promising reversal of bond strength than SA and alpha-tocopherol, and deserves further studies.

AIM: The purpose of this study is to critically evaluate the factors that affect the bond strength of one-step and two-step self-etch adhesives by using meta-analysis. MATERIALS AND METHODS: Potential papers that were selected according to inclusion and exclusion criteria from articles were published in 13 peer-reviewed journals using "PubMed data base". From each report, means and standard deviations of bond strengths were extracted and tabulated with corresponding experimental conditions. RESULTS: All the studied parameters showed no significant difference, except for dentin origin/site and bonding area. In addition, statistical analysis done with ANOVA showed statistical significance between the one-step and two-step self-etch adhesives. CONCLUSIONS: Our analysis has showed that two-step self-etch adhesive system showed a superior in vitro performance in comparison to one-step self-etch system. Nevertheless, certain factors such as dentin origin, site and area of bonding affect the bond strength of adhesives.