Immunohistochemical expression of p21 in normal tissues of salivary gland, pleomorphic adenoma and carcinoma ex pleomorphic adenoma (undifferentiated and adenocarcinoma types)

Objective: Our study aimed to characterize alteration in the immunohistochemical expression of p21 in normal tissue of the salivary gland surrounding pleomorphic adenoma, the tumor cells of pleomorphic adenomas, and carcinoma arising in pleomorphic adenoma. Study design: A selected series of 29 cases of pleomorphic adenomas, and 27 cases of carcinoma ex-pleomorphic adenoma (undifferentiated and adenocarcinoma types) were examined. Results: The results showed that p21 expression was negative in the most components of normal tissue of the salivary gland surrounding pleomorphic adenoma, 24 cases out of 29 of the non tumour duct cells (82.8%), and 28 (96.6%) cases out of 29 of the acinar cells shows negative p21 expression. P21 expression in pleomorphic adenomas shows that 2 cases out of 29 (6.9%) strongly expressed in the duct cells. p21 was strongly expressed in carcinoma cells in 9 (33.3%) cases out of 27. Conclusion: Our data suggest that the strong nuclear staining as an indicator for altered p21, then the alteration of p21 expression would increase from pleomorphic adenoma to carcinoma arising in pleomorphic adenomas (6.9% versus 33.3%)

An immunohistochemical study of the distribution of p 16 protein in oral mucosa in smokers, non-smokers and in frictional keratosis

Objective: Our study aimed to characterize alteration in the immunohistochemical p16 expression in normal oral mucosa and non-neoplastic hyperproliferative disorders (i.e. frictional keratosis and mucosa from smokers). Study design: 43 specimen of oral mucosa were examined using immunohistochemistry. Results: In normal mucosa, there was strong positive nuclear staining in a proportion of fibroblasts and endothelial cells in the lamina propria, with variable expression in nuclei of the epithelial layer. However, when the patient?s tobacco smoking was examined, p16 nuclear staining in oral epithelium was seen in 4/20 (20%) of smokers and 0/23 (0%) of non-smokers. In every case of frictional keratosis (n=11), there was strong nuclear staining of some basal and supra-basal cells. In addition, there was strong nuclear staining of parakeratinizing squamous in a band above the spinous layer. In clinically normal oral epithelium of smokers and in frictional keratosis, basal and supra-basal cells expressed strong p16 nuclear staining which was absent in the control tissue examined. Conclusion: Our data suggest that p16 expression may be involved in the long-term loss of proliferation in cell senescence of oral mucosa

Immunohistochemical expression of oestrogens and progesterone receptors in carcinoma ex pleomorphic adenoma- undifferentiated and adenocarcinoma types

Cancer of the salivary gland is one of the common cancers in the head and the neck regions. This type of cancer develops in the minor and the major salivary glands, and it sometimes metastasizes to other organs, particularly the lung. Morphologic mimicry and similarity in the expression of steroid hormone receptors between salivary gland tumors and breast tumors are well-known phenomena and are occasionally debated in the field of surgical pathology. The expression of sex hormone receptors in some tumors suggests a role for these receptors in tumor pathogenesis and therapy. Previous studies of the expression of estrogens and progesterone receptors in salivary gland tumors have reported conflicting results. Objective: Our study aimed to characterize alteration in the immunohistochemical expression of estrogens receptor and progesterone receptor in the tumor cells of carcinoma arising in pleomorphic adenoma. Study design: 27 cases of carcinoma arising in pleomorphic adenoma (undifferentiated and adenocarcinoma types) were examined. Results: The results showed that 27 (100 %) of 27 cases had negative nuclear staining for either estrogens or progesterone receptors. Conclusion: Our data suggest that carcinomas arising in pleomorphic adenoma were not dependent on endocrine function

Immunohistochemical Expression of p53 in Pleomorphic Adenoma and Carcinoma Ex Pleomorphic Adenoma

Context. Immunohistochemical stains for p53 are used as a diagnostic marker associated with malignancy in several histologic types of salivary gland tumors. This marker may be useful in differentiating pleomorphic adenoma (PA) from carcinoma ex pleomorphic adenoma (CPA), as these tumors are often difficult to distinguish on the basis of morphology alone. Objective. to evaluate whatever inactivation of tumor suppressor gene (p53) increases with the tumor progression from normal salivary tissue to PA and eventually CPA. Design. Paraffin blocks of 29 cases of PA, which were surrounded by normal parotid gland, and 27 cases of carcinoma ex pleomorphic adenoma were retrieved and validated. In all cases of carcinoma ex pleomorphic adenoma, a PA “ghost” was identified, and the malignant element was either undifferentiated carcinoma or adenocarcinoma. Results. The results showed negative nuclear expression of P53 in normal parotid gland. Nuclear P53 was expressed strongly in 6/29 (20.7%) pleomorphic salivary adenoma and 10/27 (37%) carcinoma ex pleomorphic adenoma. Conclusion. Our data suggest that inactivation of p53 may play an important role in the evolution of pleomorphic salivary adenoma and carcinoma ex pleomorphic adenoma

Assessing the association between unstimulated whole salivary flow rate (UWSFR) and oral health status among healthy adult subjects : a cross-sectional study

This study aimed to test the association between the unstimulated whole salivary flow rate (UWSFR) and the oral health status represented by dental and gingival status among healthy adult subjects. This work was a cross-sectional study of patients attending the undergraduate dental clinics at AlFarabi College for Dentistry and Nursing, Riyadh, Saudi Arabia. The study population consisted of 502 systemically healthy adults aged 18?35 years. UWSFR was collected for all study participants and expressed as ml/min. Oral health status was estimated using the Community Periodontal Index (CPI) and the Oral Hygiene Index-Simplified (OHI-S). The number of decayed teeth and the number of available teeth were also calculated to evaluate dental status. The mean UWSFR was 0.42 (±0.3) ml/min, and the male participants significantly had more UWSFR than the females. UWSFR was significantly affected by CPI, OHI-S, body mass index (BMI) and gender as indicated in the univariate analysis. However, multiple regression analysis revealed that only gender was a significant predictor of UWSFR. The male subjects were shown to have a higher average of 0.133 ml/min than the females. High BMI scores, moderate-to-severe gingivitis and low level of oral hygiene increased UWSFR. However, further longitudinal studies are recommended to test the role of salivary cytokine levels to validate the exact association between the UWSFR and the oral health status

A survey of dentists? practice in the restoration of the shortened dental arch

Objectives: The aim of this survey was to determine how a sample of dentists working in general dental practice in the UK sought to restore the mouths of patients who had shortened dental arches (SDAs). Study design: A survey was conducted over a period of six months on four commercial dental laboratories. Cases of SDAs comprising the anterior teeth and 2 to 4 premolars were examined; dental prescriptions were scrutinized and a special data collection form was completed accordingly. Results: A total of 140 SDA cases were examined. Most of these cases were for mandibular SDAs (88.6%). Of the recorded SDA cases, 67.2% were restored by cobalt-chromium based removable partial dentures (RPD); 25.7% were extended by acrylic-resin based RPDs; implants were provided to restore 8 SDA cases (5.7%); and only two SDA cases (1.4%) were extended by cantilevered fixed bridges. Neither the gender of the patient ([Chi (2)= 4.19, p>0.05) nor the length of the SDA ([Chi (2) = 6.51, p>0.05) influenced the choice of prosthesis to be implemented. Conclusions: It would appear from the results of this survey that among the different restorative treatment options for SDA, the RPD was the most popular treatment option for dentists surveyed in this UK study. Extending the SDA by either an implant-supported prosthesis or cantilevered fixed bridges did not appear to be a popular choice of treatment

Teledentistry-Knowledge, Practice, and Attitudes of Dental Practitioners in Saudi Arabia: A Nationwide Web-Based Survey

The present survey assessed the knowledge, attitudes, and practice of teledentistry (TD) among dental practitioners in Saudi Arabia. This questionnaire-based cross-sectional study was conducted with dental interns and practicing dentists in Saudi Arabia. An online questionnaire was sent to all potential respondents. Questions related to knowledge, practice, attitudes, and training regarding TD were presented. A total of 603 (227 dental interns, 376 practicing dentists) completed the questionnaire. Generally, the participants revealed poor knowledge and practice of TD, with only 38% having heard about TD and only one-quarter of the sample (23.2%) reporting practicing TD at their current workplace. However, most of the participants expressed positive attitudes and a willingness to practice TD in the future. Specialists and those in practice for >5 years showed significantly better knowledge and practice of TD than general dentists and those with lesser clinical experience (p > 0.01). While only one-fifth of the participants (20.2%) reported having attended a workshop/lecture about TD, the majority (69.7%) felt that they needed training on TD. The results revealed poor knowledge, practice, and training with regard to TD among practicing dentists in Saudi Arabia. However, the positive attitude expressed by most of the participants towards practicing TD in the future is an encouraging sign for dental educators and planners of oral health care. Continuous education through periodic workshops and training courses on TD is crucial to improve dentists’ knowledge, practice, and attitudes towards TD. Integration of TD topics into undergraduate/postgraduate curricula is highly recommended. Special attention should be directed to training general dental practitioners and junior dentists