Geometrics Morphometrics in Craniofacial Skeletal Age Estimation - A Systematic Review.

Geometric morphometrics is a novel statistical shape based technique used as an additional approach to the currently used methods in forensics for the assessment of age. Various craniofacial units are used for the estimation of age using this technique. The aim of this systematic review was to assess if Geometric Morphometrics is an accurate and reliable method in craniofacial skeletal age estimation. A literature search was conducted for cross-sectional studies on geometric morphometrics in craniofacial skeletal age estimation using various search engines such as Pubmed, Google Scholar, and Scopus using specific MESH terms. AQUA (Anatomical Quality Assessment) tool was used for the quality assessment. A total of 4 articles were included for qualitative synthesis as they met the objectives of this review. The results of all the included studies suggested that geometric morphometrics can be used for craniofacial skeletal age estimation. The centroid size calculated using digitized images or CBCT scanned images is said to be the highest predictor of age.This systematic review summarises the merits and demerits of this technique and suggests that it is rapid and accurate method for age estimation even in instances of single skeletal remains of craniofacial units and can be performed on a digitized image or a CBCT scanned images. However, further studies are needed to derive reliable data and meta-analysis can be performed effectively.

Sex estimation in Indians by digital analysis of the gonial angle on lateral cephalographs.

OBJECTIVE: Sex estimation of skeletons is important in forensic reconstructive identification. The mandible is a durable component that is suitable to discriminate the sexes while lateral cephalometry is a standardised radiographic technique accepted as a tool in personal identification. Limited data is available for the mandibular/gonial angle as a parameter for sex assessment using lateral cephalometric radiographs. The aim of this study is to determine the gonial angle's accuracy in sexing Indians using a new digital method and statistical approach. METHOD: The sample comprised of 304 digital lateral cephalometric radiographs (155 females and 149 males, age between 18-30 years) of Indian subjects. The mandibular/gonial angle was measured on these radiographs using Adobe Photoshop software using tools available therein. The obtained angles for the sexes were subjected to logistic regression analysis (LRA), which forms a composite of weighted independent variables using a multivariate strategy. RESULTS: The average angle was 122.7° for females and 121.1°for males. LRA produced an accuracy rate of 56.3% in sex assessment, with females being more accurately identified (61.9%) than males (50.3%). CONCLUSION: The study demonstrated significant univariate sexual dimorphism among males and females in this population. However, the sex prediction value of this approach was low and thus may not be useful in sex estimation involved in human identification of Indians.

Detection of metastases in oral squamous cell carcinoma: still a diagnostic impasse.

Oral squamous cell carcinoma (OSCC) being the most common malignancy of the oral cavity poses a significant public health problem due its impact on the speech, mastication, taste, swallowing and esthetics. Moreover, the presence of metastasis either regional or distant worsens the prognosis and reduces the survival rate in these patients. This makes it imperative to diagnose metastasis at an early stage to facilitate appropriate therapeutic management to reduce the morbidity and mortality associated with this disease. There have been several modalities that have been developed and in wide-use for recognition of metastasis with their inherent advantages and disadvantages making it a perplexing dilemma to the clinician and surgeon alike. This paper aims to give an insight into the diagnostic workup available for the evaluation of metastasis in patients with OSCC and reinforces the need for further research to develop more accurate methods.

Comparison of tetrachromic VOF stain to other histochemical staining techniques for characterizing stromal soft and hard tissue components.

The components of hard tissues including dentin, enamel, cementum, bone and other calcified deposits, and mature and immature collagen pose problems for identification in routine hematoxylin and eosin (H & E) stained sections. Use of combinations of stains can demonstrate the components of hard tissues and soft tissues distinctly. We assessed the efficacy of the Verde Luz-orange G-acid fuchsin (VOF) stain for differentiating hard and soft connective tissues and compared results with other histochemical staining techniques. Eighty tissue sections comprising developing tooth (30), ossifying fibroma (30) and miscellaneous pathologies (20) expected to contain varying types of calcified tissues were stained with H & E, VOF, and Masson's trichrome (MT). In developing tooth, VOF demonstrated better differentiation of hard tissues, while it was comparable to MT for ossifying fibroma and miscellaneous pathologies. The intensity of staining was greater with VOF than with the other stains studied. VOF stains hard tissue components distinctly and gives good contrast with the surrounding connective tissue. VOF is comparable to MT, but has added advantages including single step staining, rapid and easy procedures, and it distinguishes the maturity of the tissues.

Immuno-histochemical evaluation of Cathepsin D in malignant salivary gland carcinomas.

OBJECTIVE: Cathepsin D is a lysosomal acid protease secreted in increased levels in several malignancies. However, its role in salivary gland tumors has not been studied extensively. The present study aims to assess the expression of Cathepsin D in malignant salivary gland tumors and to compare its expression in these tumors. STUDY DESIGN: A total of 30 cases of malignant salivary gland carcinomas which included 16 cases of adenoid cystic carcinoma (ACC), 9 cases of mucoepidermoid carcinoma (MEC), and 5 cases of polymorphous low grade adenocarcinoma (PLGA) were evaluated immunohistochemically using anti-Cathepsin D antibody. RESULT: All the cases showed positivity (100%) for Cathepsin D with intense expression noted in ACC and MEC as compared to PLGA. Comparison of these tumors revealed statistical significant difference in expression between ACC and PLGA. CONCLUSION: Intense expression of Cathepsin D in high grade carcinomas may be a marker for invasive potential and aggressive behavior.

Efficacy of "Dimodent" sex predictive equation assessed in an Indian population.

Teeth are considered as a useful adjunct for sex assessment and may play an important role in constructing a post-mortem profile. The Dimodent method is based on the high degree of sex discrimination obtained with the mandibular canine and the high correlation coefficients between mandibular canine and lateral incisor mesiodistal (MD) and buccolingual (BL) dimensions. This has been evaluated in the French and Lebanese, but no study exists on its efficacy in Indians. Here, we have applied the 'Dimodent' equation on an Indian sample (100 males, 100 females; age range of 19-27yrs). Additionally, a population-specific Dimodent equation was derived using logistic regression analysis and applied to our sample. Also, the sex determination potential of MD and BL measurements of mandibular lateral incisors and canines, individually, was assessed. We found a poor sex assessment accuracy using the Dimodent equation of Fronty (34.5%) in our Indian sample, but the populationspecific Dimodent equation gave a better accuracy (72%).Thus, it appears that sexual dimorphism in teeth is population-specific; consequently the Dimodent equation has to be derived individually in different populations for use in sex assessment. The mesiodistal measurement of the mandibular canine alone gave a marginally higher accuracy (72.5%); therefore, we suggest the use of mandibular canines alone rather than the Dimodent method.