Objective: To assess the knowledge and attitude of dentists of Rawalpindi and Islamabad towards the use andsafety of amalgam, observance of mercury hygiene and amalgam waste management.Study Design: Cross Sectional survey.Place and Duration of Study: The study was carried out at Operative Dentistry Department of AFIDst th Rawalpindi, from 1 March to 31 April 2021.Materials and Methods: An online questionnaire was circulated among 384 private and public hospital dentistsof Rawalpindi and Islamabad. Final questionnaire consisted of close ended questions related to demographicdetails, questions regarding the handling and disposal of amalgam and perception of dentists regardingmercury hygiene. Data was analyzed using SPSS version 21 and evaluated as frequencies, percentages, meanand standard deviation. Chi-square test was used to correlate demographic to the responses of the participantsto the items of the questionnaire.Results: Majority of the dentists were doing 5-10 amalgam restorations per week (34.6%) but they didn't placerubber dam while restoring tooth with amalgam (95.7%). Most of the dentists take no specific measures forstoring leftover amalgam (65.4%) and do not periodically monitor mercury vapor (91.5%).Conclusion: The majority of dentists of Rawalpindi and Islamabad are not following dental mercury hygienerecommendations as there is a significant lack of knowledge regarding mercury hygiene and amalgam wastedisposal.

Objective: To find the effect of different combinations of Calcium Hydroxide for the management of post-operative pain in acute apical periodontitis. Study Design: Comparative cross-sectional study. Place and Duration of Study: Department of Operative Dentistry Armed Forces Institute of Dentistry, Rawalpindi. from Jun to Nov 2019. Methodology: A total of 282 patients presenting with acute apical periodontitis in their mandibular posterior teeth were selected for this study and were randomly divided into three equal groups with the help of scientific random number table. Group-A patients were given intracanal dressing of Calcium Hydroxide mixed with Chlorhexidine, group-B patients were given intracanal dressing of Calcium Hydroxide mixed with Saline and group-C patients were given intracanal dressing of Calcium Hydroxide mixed with Dexamethasone. Endodontic therapy was initiated after application of rubber dam, following pulpectomy and disinfection with frequent irrigation, canals were prepared and intra-canal dressings were placed according to the allotted group and the cavity was restored till the next appointment. Post-operative pain was recorded at 24 hours, 48 hours and one week using the visual analogue scale. Results: The three intra-canal combinations of Calcium Hydroxide used in the study were found to be equally effective in reducing pain. Overall, the result between the three groups after 24 hours proved to be insignificant (p=0.40), after 48 hours (p=0.84) and 1 week (p=0.45) were also insignificant. Conclusion: Calcium Hydroxide mixed with Saline, Chlorhexidine and Dexamethasone are all effective for pain reduction with dexamethasone being the most effective.