Parenchymal changes of salivary glands adjacent to a variety of salivary gland disorders.

A fully developed tumor is the first manifestation of a typical salivary gland neoplasm. Identification of precursor lesions and the accompanying clinical findings may improve our understanding of these tumors. The frequency of possible precursor lesions of salivary gland tumors have not been systematically investigated to date. In this study, slides of 661 cases from three pathology laboratories in Ankara, Turkey were reviewed to search for possible precursor lesions. Salivary gland parenchymal changes adjacent to a variety of salivary gland disorders such as metaplastic changes, ductal epithelial hyperplasia, adenomatoid ductal hyperplasia, adenomatoid oxyphilic hyperplasia, adenomatoid hyperplasia of the minor salivary glands, myoepithelial sialadenitis and dysplasia were screened histologically as potentially precursor lesions. Nuclear protein Ki-67 and cellular tumor antigen p53 were also analyzed immunohistochemically in selected cases. Approximately 16% of the cases in this series contained various types of pathologic hyperplasia. Only a minority of these lesions were originally reported, so most of the findings in this study were not part of the original histology reports. The majority of these parenchymal changes were seen in parotids. Adenomatoid ductal hyperplasia was the most frequent possible precursor lesion, and it was found most frequently around pleomorphic adenomas. Although the biological significance of most of the lesions described in this report still remains to be understood completely, efforts to define and detect possible preneoplastic lesions should be intensified. We believe that detection and eradication of the precursors is the best way of decreasing the overall morbidity caused by salivary gland tumors.

Clinical evaluation of apex locator and radiography in primary teeth.

AIM: The aim of this in vivo study was to evaluate the accuracy and reliability of electronic apex locater and radiographic determination of root canal length in primary teeth. METHODOLOGY: A total of 32 human primary molar teeth (96 roots) were selected. After endodontic access preparation, root canals were irrigated with physiological saline solution. The access cavities were dried with cotton pellets and, the roots were dried with paper points before performing the electronic measurement. The root canal length measurements were first taken with an apex locater (EndoMaster), and then, a size ♯ 15 K-file was inserted into the root canal, and radiography was taken to determine the working length measurements. The measurement data were recorded and compared by one-way anova and Kruskal-Wallis tests. P < 0.05 was accepted for the significance. RESULTS: The mean values for radiography were 13.23 ± 1.92 mm and for EndoMaster were 13.08 ± 1.77 mm. The accuracy of EndoMaster was 80.2% in correct measurements ±1 mm (P < 0.001). CONCLUSION: The electronic apex locators could be useful in determining working length and thereby decreasing the need for radiographs and exposure to ionizing radiation in pediatric dental patients.

KTP laser on microleakage of compomer restorations in Class V restorations.

AIM: To evaluate the effects of pulsed KTP (potassium-titanyl-phosphate) laser on decrease of dentinal microleakage of compomer restorations in primary teeth. METHOD: Twenty four primary molars were selected for the study After Class V cavity preparations in buccal and lingual surfaces, teeth were divided into three groups: Group 1: Control, Group 2: 1 WKTP laser Group 3: 1.5 WKTP laser. Then cavities were restored with compomer and teeth were thermocycled to 500 cycles, isolated and immersed in 0.5% basic fuchsin for 24 hours. Teeth were rinsed, dried, and sectioned, and microleakage was assessed by dye penetration at the occlusal and gingival surface of the teeth with stereomicroscope (40X). The data were analyzed with Kruskal-Wallis, Mann-Whitney U and Wilcoxon tests. RESULTS: When the scores of microleakage at the gingival margins of the groups were compared, the differences among the groups were found to be statistically significant (p<0.05). At the occlusal margins of the groups, there were no statistical differences (p>0.05). Comparing the gingival and the occlusal margins in the each group, statistically significant differences existed in the Groups 1 and 3 (p<0.05). CONCLUSIONS: KTP laser is able to seal dentinal tubules and consequently reduce microleakage towards pulp in primary teeth.