Hitesh Vij

Evaluation of collagen in connective tissue walls of odontogenic cysts ― A histochemical study

BACKGROUND The purpose of this study was to evaluate the nature of collagen in the connective tissue walls of odontogenic cysts, like the odontogenic keratocyst (OKC), dentigerous cyst and radicular cyst using picrosirius red stained sections. Furthermore, it was intended to assess if the capsular connective tissue can affect the nature of overlying epithelium, thus emphasizing the role of epithelial-mesenchymal interactions in biological behaviour of the cysts. MATERIALS AND METHOD The material for the study included 51 formalin-fixed paraffin-embedded tissue blocks (15 odontogenic keratocyst, 15 dentigerous cysts, 15 radicular cysts and four normal mucosa and two dental follicular tissue as controls), retrieved from the Department of Oral Pathology and Microbiology, MCODS, Manipal. Tissue blocks were sectioned at 5-μm thickness, stained with picrosirius red stain and observed with polarization and light microscopy. RESULTS Few sections of OKC and dentigerous cyst exhibited greenish-yellow birefringence in sub-epithelial region, whereas others showed a yellowish-orange birefringence under polarization microscopy. Most radicular cysts had yellowish-orange to orange birefringence. Shift in colour in case OKC and dentigerous cyst was attributed to the presence of inflammation in those sections. These regions also exhibited either a change in phenotype or thickness of overlying epithelium. CONCLUSION This technique can be used to study the nature of collagen fibres in odontogenic cyst walls. Further studies with an increased sample size and using various epithelial and mesenchymal markers and ssDNA antibodies should be carried out to confirm the effect of epithelial-mesenchymal interactions on the nature of epithelium of odontogenic cysts.

Rhabdomyosarcoma of mandible: A diagnostic predicament

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children under 15 years of age and rare among persons older than 45 years of age. It is considered to result from malignant transformation of primitive mesenchymal cells. Although it has a relative predominance for head and neck region, it is found less often in oral cavity. Here we report a case of RMS of mandible in an adult patient, which was initially diagnosed as carcinosarcoma. Clinical and pathologic findings are described, which were confirmed by histochemical and immunohistochemical stains.

Expression of tenascin and nucleolar organizer region in ameloblastoma and ameloblastic fibroma

BACKGROUND The aim of this study was to assess the expression, distribution and comparison of tenascin, a glycoprotein of the extracellular matrix in ameloblastoma and ameloblastic fibroma, both odontogenic neoplasms with diverse biological behavior and to understand the proliferative activity by using the morphometric analysis. METHODS Paraffin embedded tissue from 25 cases of odontogenic tumors i.e., ameloblastoma (n = 15) and ameloblastic fibroma (n = 10) were used. The expression of tenascin was evaluated using immunohistochemistry. Morphometric analysis of nucleolar organizer regions (NORs) from ameloblastoma and ameloblastic fibroma was carried out by silver staining. RESULTS A heterogeneous expression of tenascin was found in ameloblastoma which was mainly localized at the epithelial-mesenchymal interface and a patchy distribution was observed in the stroma (80%), while strong positivity was observed in the stroma and at the basement membrane zone of ameloblastic fibroma (100%). argyrophilic nucleolar organizer regions (AgNORs) revealed higher mean counts in ameloblastoma (3.093 +/- 0.902) when compared with those of ameloblastic fibroma (1.553 +/- 0.250). Ameloblastoma presented more than two NORs (two to five) per nucleus in majority of the cells, while ameloblastic fibroma exhibited only one NORs per nucleus. CONCLUSIONS Expression of tenascin in these neoplasms suggest that it could play a role in epithelial- mesenchymal interaction, while AgNORs reveal that ameloblastomas are more aggressive when compared with ameloblastic fibromas.

Forensic odontology as a victim identification tool in mass disasters: A feasibility study in the Indian scenario

Aim: The aim of this study was to evaluate the awareness of practicing dentists about the subject of forensic odontology and to assess their willingness to maintain and share patient records. Materials and Methods: A blind questionnaire survey was carried out among 100 randomly selected practicing dentists in district Ghaziabad, Uttar Pradesh. Results: Most of the dentists interviewed were familiar with the subject of forensic odontology and its relation to dentistry, despite forensic dentistry having been newly introduced since 2007 into the undergraduate dental curriculum in India. However, dental records are maintained by only a few dentists, and only a very small percentage of them reported to have shared records, which may have helped in the identification of victims in a mass disaster. Conclusion: The result of our survey concluded that more awareness needs to be developed among practicing dentists regarding maintaining and sharing patient records for forensic odontology to succeed as a victim identification tool.

An erupted compound odontoma.

Odontomas are familiar entities but their eruption into the oral cavity is an extraordinary occurrence, which may be associated with pain, infection, malocclusion, etc. Not many cases of erupted odontomas have been reported in the literature. This paper puts forth a case of erupting odontoma in an attempt to add to the list of reported cases of this unique pathology.

Cleidocranial dysplasia: complete clinical, radiological and histological profiles.

Cleidocranial dysplasia is an autosomal-dominant condition characterised by widely patent calvarial sutures, clavicular hypoplasia, supernumerary teeth and short stature. Though it is not a very uncommon occurrence, its histopathological features are not frequently reported. This paper presents a similar case with complete clinical, radiological, histological and treatment profiles.

Ameloblastic fibroma: an uncommon entity

Ameloblastic fibroma is an uncommon mixed odontogenic tumour, which is often confused with ameloblastoma. It exhibits both epithelial and mesenchymal components with absence of any calcified dental structure. This paper presents two cases of this rare entity with detailed review of literature.

Heterotopic Tooth: An Exceptional Entity.

A 30-year-old female patient reported to the dental clinics with a complaint of missing teeth. On clinical evaluation maxillary left pre-molars and mandibular left second molar were absent, the patient was free from any gross pathology and a set of radiographs was advised for analysis of periodontal health and treatment planning. Radiographs revealed the presence of an impacted 3rd molar tooth in the left coronoid process [Table/Fig-1], though clinically no signs or symptoms were observed. Since the location of tooth was abnormal the case was diagnosed as “ectopic 3rd tooth in coronoid process”. [Table/Fig-1]: Orthopantomogram showing ectopic 3rd molar in left coronoid process As the literature suggests such asymptomatic patients can be kept under regular follow-up without any surgical intervention till there is any associated pathology or discomfort. The patient was motivated for placement of implants in edentulous areas and was informed regarding the presence of the ectopic tooth. All the possible complications which could arise in relation to the ectopic tooth were explained to the patient. Further, the patient was advised to have a regular follow-up and visit the dental clinics in case even slight discomfort arose in the concerned region. Occurrence of impacted 3rd molar tooth is not uncommon but an impacted 3rd molar tooth in an abnormal location (ectopic tooth) is not encountered very frequently [1]. As per the reviews very few cases of ectopic 3rd molar tooth have been reported in English literature [1,2]. Hence, it becomes difficult to comment about the epidemiology of these ectopic teeth. The aetiology of this phenomenon also remains obscure, though many theories have been put forth to explain this exceptional event [2]. This paper presents a case of an ectopic tooth in coronoid process. Only 6 cases of this condition have been reported till date, thus the current case is another milestone of this rare occurrence [1]. A tooth may be impacted, by soft tissue alone or it might be a bony impaction, but the location of the tooth is close to its physiologic position [3]. When such impacted teeth have dislocated to distant regions such as condylar process, mandibular ramus, maxillary sinus, nasal cavity etc these are referred to as ectopic teeth [1,2]. Keros and Susic referred to this condition as “Heterotopic position of tooth” in his report [4]. Occurrence of ectopic tooth as such is an uncommon phenomenon and ectopic tooth in coronoid process is even rarer [1], the latter scenario was observed in the current case. It is not always possible to determine the exact cause of an ectopic tooth. Various authors have suggested different possible aetiologies which may be either pathologic such as cysts, developmental like an abnormal eruptive pattern or tooth germ development in abnormal location, or sometimes traumatic or iatrogenic in nature [1,2]. In the present case the causative factor appears to be developmental aberration since there was no associated pathology or any history of trauma or surgical interventions in relation to the jaws. Due to the sporadic nature it is not appropriate to definitively comment about the gender predilection, site, clinical signs and symptoms, etc of ectopic 3rd molars. Most of the reported cases in literature are in women and located in mandibular subcondylar or condylar region [1]. In present case too patient was a female but the tooth was located in an atypical position i.e. the coronoid process [Table/Fig-1]. The clinical symptoms may be in the form of pain and swelling, trismus or sometimes fever with acute inflammation and draining sinus [2]. In the case under discussion the patient was asymptomatic and it was an incidental finding. Asymptomatic cases are generally kept under regular follow-up with radiographic evaluation, as was done in the current case. Ectopic tooth associated with cysts are generally surgically treated conservatively until the cyst is very small. In latter case patient is kept under regular follow-up with radiographic evaluation as is done in asymptomatic cases. Intraoral approach is preferred if possible to avoid scarring of facial skin [5]. Based on various reported cases and reviews of ectopic tooth it can be said that coronoid process is not a common location for occurrence of this phenomenon. Further, it is a must that asymptomatic cases are kept under regular follow-up to monitor the development of any new symptoms or pathology or observe any increase or decrease in the associated pathology.

Modified technique for soft tissue processing and staining

Abstract Use of xylene as a clearing agent during tissue processing and the subsequent hematoxylin and eosin staining process have become inseparable parts of histopathology laboratories. While using these reagents, one must keep in mind the well-documented health hazards of xylene and the stability, the cost factor, and the shortage of hematoxylin, which has been faced once and may recur since it is obtained from a natural resource. Thus, this study was carried out to find suitable substitutes for xylene and hematoxylin. To compare xylene and chloroform, ten biopsy tissues fixed in formalin were cut into two; one piece of each biopsy was cleared in xylene and the other piece in chloroform. All the other reagents used in the tissue processing remained the same. The tissues were then sectioned and stained with hematoxylin and eosin. Further, two tissue sections were obtained from tissues of differing natures and stained with hematoxylin and eosin and Celestine blue and eosin, in order to compare and evaluate hematoxylin and Celestine blue. In both cases, the staining intensity of selected fields was evaluated at regular intervals. Staining intensity of sections following clearing with chloroform was more stable over a period of time as compared to those cleared with xylene. The staining of sections with Celestine blue was comparable to that of hematoxylin and was not affected by the nature of the tissue. Results of the present study suggest that chloroform has specific advantages as a clearing agent as compared with xylene. Furthermore, Celestine blue is a steadfast substitute for hematoxylin.