Dental Research Journal
Volume:9 Issue: 7, Nov 2012

Ghost cells have been a topic of controversy since a long time. The appearance of these cells in different lesions has given it varying terms. In lesions like that of Calcifying cystic odontogenic tumor (CCOT), these cells have been termed as ‘Ghost cells’ whereas similar descriptive cells have been called shadow/translucent cells in non‑odontogenic lesions like Craniopharyngiomas of the pituitary gland and Pilomatricomas of skin. Controversy arises because of the fact that there are varying opinions and incomplete knowledge about their origin, nature, significance and relation in different neoplasms. Irrespective of the origin, these cells are seen in odontogenic and non‑odontogenic neoplasms, which probably direct us towards a missing link between these differing neoplasms. This article attempts to present a review on the concepts around these peculiar cells and shed some light on these ghosts that are still in dark.

Salivary gland tumors are relatively uncommon and account for approximately 3-6% of all neoplasms of the head and neck. Tumors mostly involve the major salivary glands, 42.9-90% of which occur in the parotid glands and 8-19.5% in the sub‑mandibular glands; tumors in the sub‑lingual glands being uncommon. Despite the plethora of different malignant salivary gland tumor presented to pathologists for diagnosis, there is consensus on a limited number of pathologic observations that determine treatment and outcome. There are few absolutes in salivary gland tumor diagnosis given the marked spectrum and overlap of differentiated cell types that participate in the numerous benign and malignant tumors. Thus, there are enumerating antibodies that may be helpful in resolving difficult differential diagnoses when applied with astute morphologic correlation. In general, immunohistochemistry as an ancillary diagnostic tool should be used sparingly and wisely as a morphologic adjunct because of the lack of specificity of many markers for specific histologic tumor types. The aim of this review is to discuss the molecular profiling of salivary gland neoplasms and correlate this with histogenesis of salivary gland neoplasms. We have elected to discuss and illustrate some of the unusual salivary gland tumors that the practicing pathologist find difficult to diagnose. These have been selected because they readily simulate each other but have very different clinical therapies and, therefore, should be included routinely in differential diagnosis.

Xerostomia is the medical term for the subjective complaint of dry mouth due to a lack of saliva. Xerostomia is sometimes colloquially called pasties, cottonmouth, drooth, doughmouth or des (like a desert). Several diseases, treatments and medications can cause xerostomia. It is also common in smokers. Treatment of xerostomia is a common clinical challenge in the oral medicine practice. Although some treatments have been used to improve the symptoms of xerostomia, none is completely satisfactory for the patients who suffer of this alteration. This review is aimed at presenting new developments for the treatment of xerostomia.

Most common impacted teeth are the mandibular third molars and decision about extraction of them is usually controversial. The presence of pericoronal pathologic changes is an acceptable reason for removal of impacted teeth. Differences in the proliferation rate and apoptosis of odontogenic epithelial cells may influence on the formation of odontogenic epithelial lesions. Therefore, the aim of the present study is to evaluate the immunohistochemical expression of the bcl-2 apoptosis-inhibiting protein and the cell-cycle-related ki-67 antigen in pericoronal follicle of impacted third molars with ≥2.5 mm and <2.5 mm radiolucency. This was a cross-sectional study that 20 follicles with <2.5 mm radiolucency and 20 follicles with ≥2.5 mm radiolucency were selected by a professional radiologist in digital panoramic radiographs and then referred to a surgeon. Formalin fixed paraffin-embedded tissues were immunohistochemical analyzed for immunoreactivity of bcl-2 protein and ki-67 antigen. The data was analyzed using logistic regression, Spearman correlation coefficient and t-test and Mann-Whitney. P<0.05 was considered significant. The findings showed correlation between size of the third molar’s follicles and expression of bcl-2 protein (P < 0.001, r = 0.556) but there was no correlation between size of third molar’s follicles and staining with ki-67 antigen (P = 0.546, r = 0.098). The follicles with radiolucency ≥2.5 mm showed increased immunoreactivity for bcl-2 protein. The results of study suggest that impacted third molars with radiolucency ≥2.5 mm may be associated with deregulation of cell death, indicated with increased expression of the anti- apoptotic protein bcl-2, while cell proliferation (ki-67) does not seem to play a significant role.

A review of literature revealed that, although the involvement of temporomandibular joint (TMJ) in rheumatoid arthritis (RA) patients is not uncommon, variation in presentation persist. Comparative studies of bony changes in the right and left TMJ with the right and left peripheral hand (Metacarpophalangeal-MCP)/wrist joints have not been done, to the best of our knowledge. In this cross-sectional study, the temporomandibular and hand (MCP) and wrist joints of fifteen rheumatoid arthritis patients were evaluated with questionnaires, clinical and lab assessment and radiographically using conventional radiographs and computed tomography. Students t-test was applied for the statistical analysis of the data obtained and a P value of 0.05 was considered as statistically significant. Comparisons between the right TMJ with right MCP/wrist joint and left TMJ with left MCP/wrist joint did not reveal statistically significant results. Radiographically, flattening and erosions were the common manifestations. MCP joints were more affected than the wrist, but whenever the wrist was involved, it was more likely to be bilaterally affected. Although the TMJ showed osseous changes of a higher grade than the hand (MCP) and wrist joints radiographically, it was observed that patients were more aware of the peripheral joint discomfort. There were no significant differences between TMJ and peripheral joints on both right and left sides.

Odontogenic keratocyst (OKC) is an aggressive cyst and its recurrence is higher than other odontogenic cysts, orthokeratinized odontogenic cyst (OOC) is a cyst with moderate biological behavior in comparison with OKC, but with the probability of carcinomatous changes. The present study aims to evaluate the quantity and intensity of the expression of P53 protein and transforming growth factor alpha (TGF-alpha) in OKC and OOC in order to compare the biologic behavior of these two cysts. This is a cross-sectional study. The samples include 30 cysts (15 OKC and 15 OOC), all stained immunohistochemically for P53 protein and TGF-alpha by the Novolinkepolymer method. Then, all the cases were examined with an optical microscope with ×400 magnification and the stained cells were counted in the basal and parabasal layers. Finally the results were analyzed by the Mann−and Wilcoxon tests (P value < 0.05). The difference between the expression of P53 protein in the basal layer in OKC and OOC was not statistically significant (P value = 0.076). The difference between the expression of P53 protein in the parabasal layer in OKC and OOC was statistically significant (P value = 0.003); moreover, the difference between the expression of TGF-alpha in the basal layer in OKC and OOC was not statistically significant (P value = 0.284). The difference between the expression of TGF-alpha in the parabasal layer in OKC and OOC was statistically significant (P value = 0.015). Since there was a higher expression of P53 protein and TGF-alpha in OKC compared to those in OOC, the probability of carcinomatous changes was at least theoretically higher in OKC than in OOC.

Some studies have been performed on assessing the anatomical variations of lingual foramen and its bony canals, in many different countries but no study has been performed in Iran yet. The purpose of this study is to assess the anatomical variations of lingual foramen and its bony canals with cone-beam computed tomography (CBCT) imaging in Isfahan. This was a cross-sectional study in which CBCT images taken from 102 patients referred to the Radiology Department of Head and Neck in Esfahan (Iran) University between 2010 and 2011. The presence of the lingual foramen and its bony canals, the locations, sizes, and length were assessed. The distances between the terminal end of lingual canal at the buccal and lingual side from the inferior border of the mandible and alveolar crest were measured. We also evaluated the effect of patient age and gender on the dimensional measurements of the anatomical landmark mentioned above t test, analysis of variance (ANOVA), and pearson’s correlation were used for statistical analysis and P value lower than 0.05 was considered significant. All of the CBCT images taken showed the presence of lingual foramen. Of all the participants, 52% of them had two foramens in their images. The mean diameters of the upper and lower lingual foramen were 1.12 and 0.9 mm, respectively. These anatomical landmarks in Isfahan population vary from previous studies. All of the images had at least one lingual foramen which demonstrates high prevalence of this anatomy among Isfehanian population. Therefore, it is recommended to use CBCT imaging for preoperative evaluation prior to installing dental implants.

The styloid process and the attached ligaments have the potential for calcification and ossification in specific conditions. The purpose of this study was to evaluate the relationship between the elongated styloid process (ESP) frequency and some of the systemic health factors of patients over 40 years of age. In this analytical‑descriptive study, 296 panoramic radiographs of patients over 40 years of age (165 female and 131 male) referred to the Dental School of Khorasgan Azad University were selected. The length of the styloid process was measured by a special ruler and recorded in a questionnaire form. Other data such as sex, age, height, weight, blood pressure, heartbeat and the number of teeth present in the mouth were also recorded. The lengths equal to or more than 30 mm on the radiographs were considered as ESP. Data analysis were done by independent t‑test, Pearson correlation coefficient and Chi‑square test at a significance level of < 0.05. ESP was observed in 135 cases (45.6%). There was a significant relationship between ESP and the body height, weight and the blood pressure, but there was no significant correlation between ESP, the heartbeat and the number of teeth present in the mouth. Because of the significant relationship between the length of the styloid process and the blood pressure, height and weight it is reasonable to evaluate a patient’s systemic health conditions when radiographic signs of ESP are observed.

the aim of this study was to evaluate linear measurement accuracy of CBCT Newtom VG (Quantitative Radiology, Verona, Italy) in vitro. CBCT is dedicated to dental and Maxillofacial imaging particularly for surgical and prosthetics implant planning in dentistry. Linear measurement accuracy is important in selection of implant type, size, orientation and number of implants. 22 anatomic landmarks in 4 dry skulls were marked by gutta – percha. 15 linear measurements were obtained using a digital caliper. These were considered as real measurements. Skulls were scanned at two settings: (a) voxel size 0.3mm (b) voxel size 0.15 mm High Resolution (HR). Radiographic distance measurement were made using the NNT viewer software in axial and coronal sections by three observers. The data were compared by mean difference, standard deviation and Intraclass Correlation Coefficient (ICC). Mean difference of real and radiographic measurements was -0.10 0.99 mm in axial sections, -0.271.07 mm in coronal sections, +0.14 1.44mm in axial (HR) sections, 0.02 1.4mm in coronal (HR) sections. The ICC for CBCT measurements in axial sections was 0.9944, coronal sections 09941, axial (HR) sections 0.9935, coronal (HR) sections 0.9937. Statistical analysis showed high interobserver and intraobserver reliability. CBCT is reliable in linear measurement in different image planes in maxillofacial area. Voxel size has no effect on accuracy of linear measurements, so by reducing radiation dose we can have images with the same dimensional accuracy.

Mucopolysaccharidosis type I (MPS I) is caused by a deficiency of alfa‑iduronidase (IDUA), which leads to intralysosomal accumulation of glysosaminoglycans. Evidences point secondary events like oxidative stress on lysosomal storage diseases including MPS I. Patients with MPS I present a wide range of oral clinical manifestations, including tongue hypertrophy, hypertrophyc alveolar process, and carious teeth. However, the mechanisms by which these alterations occur are still not fully understood. The aim of this study was to analyze the proliferative activity as well as apoptosis in tongue mucosa cells from murine model of MPS I. Protein expression of apoptotic markers such as p53, bcl‑2 and bax were evaluated in this setting. Ki‑67 was used as a proliferative marker. All analyses were made by immunohistochemistry in tongue cells. Statistical analysis was perfomed by Kruskal-Wallis nonparametric test followed by the Dunn’s test. P < 0.05 was considered for statistic significance. Histopathological analysis revealed no remarkable differences in tongue mucosa on MPS I mice when compared to control. By contrast, our results demonstrated that bcl‑2 immunoexpression was decreased in mice tongue mucosa cells of MPS I mice. p53, bax and ki‑67 immunoexpresssion did not show significant differences among controls and MPS I mice. Taken together, our results suggest that IDUA deficiency, which characterizes MPS I, may induce apoptosis in mice tongue cells as a result of bcl‑2 down regulation.

Recent studies have shown that lactoferrin promotes the proliferation and differentiation of osteoblasts and inhibits osteoclast‑mediated bone resorption. Anorganic bovine bone (ABB) graft has been extensively used as an osteoconductive material in the bone reconstructive surgeries. The purpose of this study was to examine whether the combination of lactoferrin with Bio‑Oss would improve ossification in experimentally induced bone defects in rabbit calvaria. In this randomized, prospective animal study, a total of 32 bone defects with the diameter of 6 mm were created on the calvaria of 8 male New Zealand rabbits (4 defects in each animal). One defect was filled with ABB + Lactoferrin + Vehicle (BLV), the second one with ABB + Lactoferrin (BL), the third defect with ABB + V (BV), and the fourth defect was filled with ABB (B) alone. After 4 weeks, histologic sections were prepared and evaluated histologically and histomorphometrically. The type, percentage and vitality of newly formed bone, inflammation, percentage of residual material, and foreign body reaction were assessed for each specimen. Data were analyzed using Friedman tests. All groups were similar in terms of inflammation and vitality, type, percentage of new bone formation, and residual material. The percentage of new bone formation in BLV, BL, BV, and B groups were 14.73 ± 3.14%, 15.02 ± 1.51%, 15.95 ± 2.24% and 13.44 ± 2.89% (P = 0.1) and the amount of residual biomaterial were 11.85 ± 1.50%, 13.73 ± 1.80%, 13.02 ± 1.86%, and 15.41 ± 2.05%, respectively (P = 0.392). Based on results of this study, the combination of lactoferrin and ABB did not show any significant improvement in bone regeneration compared with ABB alone in surgically induced bony defects in rabbit calvaria.

Bone density measurement in a radiographic view is a valuable method for evaluating the density of bone quality before performing some dental procedures such as, dental implant placements. It seems that Cone‑Beam Computed Tomography (CBCT) can be used as a diagnostic tool for evaluating the density of the bone, prior to any treatment, as the reported radiation dose in this method is minimal. The aim of this study is to investigate the effect of object location on the density measurement in CBCT versus Multislice computed tomography (CT). In an experimental study, three samples with similar dimensions, but different compositions, different densities (Polyethylene, Polyamide, Polyvinyl Chloride), and three bone pieces of different parts of the mandibular bone were imaged in three different positions by CBCT and Multislice CT sets. The average density value was computed for each sample in each position. Then the data obtained from each CBCT was converted to a Hounsfield unit and evaluated using a single variable T analysis. A P value <0.05 was considered to be significant. The density in a Multislice CT is stable in the form of a Hounsfield Number, but this density is variable in the images acquired through CBCT, and the change in the position results in significant changes in the density. In this study, a statistically significant difference (P value = 0.000) has been observed for the position of the sample and its density in CBCT in comparison to Multislice CT. Density values in CBCT are not real because they are affected by the position of the object in the machine.

The mastoid pneumatization begins on the 33rd week of embryonic life, and continuous up to 8-9 years of age. This air cells is important for surgical perspective. Inadvertent penetration through this anatomical feature during surgical procedures can be disastrous. Aim of this study is to determine the prevalence of zygomatic air cell defect (ZACD) in the Esfehanian population. This was a cross‑sectional study. 2600 panoramic radiographs of patients aged between 3 and 90 years were evaluated retrospectively to establish dominant laterality, type and grade amongst these patients. The SPSS 11.5 program was used for the statistical analysis. Mean and standard deviation were used for statistical methods in this study. ZACD was found in 94 cases, representing a prevalence of 3.6%. 59 cases occurred in females (62.8%) and 35 cases occurred in males (37.2%). Most cases were in their twenties. Unilateral ZACD was found in 70 patients (74.5%) with the half occurring on the right side. In 24 cases (25.5%) was bilateral. 70 of the cases (59.3%) were multilocular type, while 45 (38.1) and 3 (2.6%) were unilocular and trabecular type, respectively. 59 cases were grade 2 (62.8%) and 35 were grade 3 (37.2%). The frequency of ZACD amongst Iranian population was more than previous studies. In addition younger population was involved in this group. So it is important for clinicians who are planning to perform temporomandibular joint surgery to assess radiographic imaging thoroughly before the surgery to avoid intraoperative complications.

There is a variation in trends of oral cancers all over the world. Many investigations have reported evidence of an increasing incidence in oral cancers during recent years. The purpose of this study was to investigate time trend and changes in demographic distribution of oral cancers incidence in Isfahan during 1991-2010. In this retrospective analytic study archive of Oral Pathology Department of School of Dentistry, Isfahan University of Medical Sciences from 1991 to 2010 were reviewed. A total of 231 Pathology reports were analyzed. Age, sex, primary site, histologic type of cancer, and the referral year were recorded. Data were analyzed by using Jointpoint Regression Program 3 and SPSS 18. P value less than 0.05 consider as significant level. Out of all malignancies, 55% were male and 45% were female. The most frequent cancer was squamous cell carcinoma. Comparing the two time intervals (1991-2000) and (2001-2010) showed that the ratio of carcinomas and salivary gland tumors had decreased while there was an increase in incidence of sarcomas and lymphomas. Among young persons, the occurrence of oral carcinomas (mostly SCC) is rare but sarcomas were more common in younger patients. Gingiva was the most frequently involved in oral cancers with (46%), followed by tongue with (18%). According to this study it revealed that some changes in trends of oral cancer have happened in Isfahan that calls for more study and evaluation of etiologies of these changes.

Leukoplakia, is a precancerous lesion that is most commonly encountered in the oral cavity. The grade of dysplasia is presumed to be the most important indicator of malignant potential. There are many promising aspects in advanced methods for the evaluation of oral precancer and cancer. Among these methods, electron microscopic examination predicts the true biologic potential more accurately than conventional histology and has some success in the early detection of potentially malignant lesions. It has been reported in the literature that there is some correlation between clinical, histopathological, and transmission electron microscopic features. In this cohort study (prospective research), from the total of 9 subjects, 3 had homogenous leukoplakia, 3 had ulcerative type of oral leukoplakia, and 3 had nodular type of oral leukoplakia. Two patients were selected as control patients. Transmission electron microscopic examination was carried for all the cases and controls. All the findings were correlated with clinical features and light microscopy. Clinically and histologically, mild leukoplakia showed break in basement membrane, which can only be observed under transmission electron microscope (TEM). Additional dysplastic features were observed under transmission electron microscope, which are indicative of neoplastic process. Thus, it is finally concluded that nodular leukoplakia seems to be the most severe clinical type of leukoplakia showing highest risk of malignant transformation. Homogenous leukoplakia might show break in basement membrane under TEM.

Hypodontia or congenitally missing teeth is among dental anomalies with different prevalence in each region. The aim of this study was to evaluate the prevalence of congenitally missing permanent teeth in Iranian population. A descriptive, retrospective and cross‑sectional study was done. Panoramic radiographs of 2422 Iranian patients (1539 girls and 883 boys), 7‑25 years old, were collected. The radiographs were studied for evidence of congenitally missing teeth. Data were analyzed using Paired t‑test, Mann‑Whitney test, Fisher exact test and Chi‑square test (α = 0.05). Prevalence of congenitally missing teeth was totally 45.7% and 34.8% for third molars. The most frequent congenitally missing teeth was mandibular second premolars (23.34%) followed by maxillary second premolars (22.02%). Upper jaw showed significantly higher number of congenitally missing teeth (P value < 0.001). According to Chi‑square test, congenital missing teeth was found approximately 10.9% in both females and males and there were no statistically significant difference between sexes (P = 0.19). The prevalence of congenitally missing teeth (CMT) in Iranian permanent dentition was 10.9%. The most common congenitally missing teeth were mandibular second premolar fallowed by maxillary second premolars.

To assess the effect of smoking on lip and gingival pigmentation and also to assess the relationship of pigmentation with periodontal parameters. 109 smokers and an equal number of control subjects who were nonsmokers in the age range of 35 – 44 years comprised the study sample. All the participants were assessed for pigmentation on lip and gingiva and a total periodontal status examination was done with measurements on gingival bleeding, probing depth and loss of attachment at six points in each tooth. Melanin pigmentation on lips and gingiva was observed in all the smokers except for one who did not exhibit gingival pigmentation. Significantly greater number of smokers exhibited pigmentation than nonsmokers. Gingival bleeding on probing, probing depth and loss of attachment differed significantly in relation to gingival and lip pigmentation. Oral pigmentation was widespread and more commonly observed in smokers than nonsmokers and there was a relationship between pigmentation and periodontal deterioration.

Adenoid cystic carcinoma (ACC) occurs more commonly in the minor salivary glands of the palate on than the tongue. ACC is a malignant neoplasm that accounts for 1‑2% of all head and neck malignancies and 10‑15% of all salivary gland malignancies. ACC affects the exocrine glands at any site, but the parotid gland is the most common site in the head and neck region. Many factors should be taken into account in the prognosis of ACC, including the histological and clinical stages of the disease. The most striking feature of ACC is that it is locally aggressive, with a high recurrence level, perineural invasion and distant metastases, especially to the lungs and bones. The most common presentation histologically is the presence of cribriform appearance (Swiss cheese pattern). The present case is a rare one present on the tongue.

Intraosseous schwannomas is a very rare neoplasm, and less than 50 cases have been reported in the medical literature. In this article, the clinical, radiographic and histopathologic appearances of a rare case of intraosseous schwannomas are presented. The importance of this case is that other benign central lesions such as odontogenic tumors and cysts might be included in differential diagnosis. This case was recognized in a 9‑year‑old child, which is a very rare occurrence. The diagnosis was confirmed by immunohistochemical staining with S100 protein.

Wegener’s granulomatosis (WG) is an immunologically mediated inflammatory disease characterized by granulomatous vasculitis of the upper and lower aerodigestive tracts together with glomerulonephritis. We are reporting a rare case of gingival WG that presented with erythematous and painful generalized gingival enlargement. Correlation of histopathology with routine hematoxylin and eosin and special stains [Grocott‑Gomori methenamine‑silver nitrate and Periodic Acid Schiff (PAS)], Mantoux test, peripheral blood smear and clinical presentation were established in diagnosing this rare entity. By the above‑mentioned procedures and methodology, we have arrived at the diagnosis of Wegner’s granulomatosis limited to the upper aerodigestive tract. Therefore, the aim of reporting this case was to emphasize that, the dental surgeon often being the first person to examine the oral cavity, should be familiar with the typical appearance of gingival WG as “strawberry gingivitis,” its clinical course as well as diagnostic parameters and adequate management. To the best of our knowledge, this is the first reported case of WG manifesting as “strawberry gingivitis” in the Indian population.

Lymphoma is a malignant neoplasm of lymphoid tissue which is divided into 2 groups: Hodgkin and non‑Hodgkin. About 85% of non‑Hodgkin lymphomas are B‑cell lymphomas, and T‑cell lymphomas are unusual. Anaplastic large cell lymphoma (ALCL) is a kind of non‑Hodgkin lymphoma with T or NK cell origin that is rarely seen in the oral cavity and only 10 cases have been reported up to now. Here we present a case of ALCL metastasized to the oral cavity in a 32‑ year‑ old man with pervious history of ALCL which caused an ulceration in the posterior area of the hard palate. Radiography showed irregular resorption of alveolar bone. Histopathologic examination of the incisional biopsy revealed neoplastic proliferation of large and bizarre cells with hyperchromatic nuclei and numerous giant cells and atypical mitoses. Immunohistochemistry markers (CK, LCA, CD3, CD30, CD20) confirmed the diagnosis of ALCL.

One of the normal interesting variations that we may encounter in the mandible is bifid mandibular canal. This condition can lead to difficulties when performing mandibular anesthesia or during extraction of lower third molar, placement of implants, and surgery in the mandible. Therefore diagnosis of this variation is sometimes very important and necessary.

The congenital granular cell epulis (CGCE) is a rare tumor, which is apparent at birth. The histogenesis is still uncertain, but several theories, including origin from epithelial, undifferentiated mesenchymal cells, pericytes, fibroblasts, smooth muscle cells, and nerve‑related cells have been proposed. This case report describes management of a 2‑day‑old baby girl having a large, round, soft, single 3 × 4 cm, pedunculated swelling, on the lower anterior ridge, which was causing difficulty in feeding. Clinical diagnosis of congenital epulis (CE) was made and lesion was excised under conscious sedation. A vessel running over the surface of the lesion was continuous on the alveolar ridge. To reduce intra‑operative hemorrhage transfixion suture was passed around the vessel on the alveolar ridge. Then the lesion was excised from the base of peduncle with a scalpel. Histopathologically, the diagnosis of a congenital granular cell lesion of the jaw was given. Follow up of 3 months shows no signs of recurrence. CGCE may interfere with feeding, requiring a conservative excision as soon as the child is fit to undergo surgery. Tendency for recurrence and malignant transformation has not been documented.