Objective: The aim of the present in-vitro study was to assess antimicrobial efficacy of 0.8% hyaluronic acid (HA) and 0.2% Chlorhexidine gluconate (CHX) against Porphyromonas gingivalis (P. gingivalis). Methods: The study was performed between December 2018 and March 2019 at the College of Dentistry at the Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia. The P. gingivalis biofilms were formed and grown for 72 hours at 37°C under anaerobic conditions on glass slides coated with human saliva. The slides were individually positioned and exposed to 0.8% HA or 0.2% CHX. Therapeutically, the biofilms were divided into 3 groups as follows: (a) negative group; (b) 0.8% HA group and (c) 0.2% CHX group. P-values less than 0.05 were considered statistically significant. Results: In the 0.8% HA group, P. gingivalis CFUs/ml were significantly higher at baseline than at 24- (P<0.05), 48 (P<0.05) and 72 hours (P<0.05) intervals. In the 0.2% CHX group, P. gingivalis CFUs/ml were significantly higher at baseline than at 72 hours interval (P<0.05). In the CHX group, there was no difference in P. gingivalis CFUs/ml between baseline, 24- and 48-hours intervals. At 48- and 72-hours intervals, the P. gingivalis CFUs/ml were significantly higher in the 0.2% CHX group compared with the 0.8% HA group. Conclusion: In-vitro, 0.8% HA is more effective in reducing the P. gingivalis CFUs/ml compared with 0.2% CHX. doi: https://doi.org/10.12669/pjms.36.2.1456 How to cite this:Binshabaib M, Aabed K, Alotaibi F, Alwaqid M, Alfraidy A, Alharthi S. Antimicrobial efficacy of 0.8% Hyaluronic Acid and 0.2% Chlorhexidine against Porphyromonas gingivalis strains: An in-vitro study. Pak J Med Sci. 2020;36(2):111-114. doi: https://doi.org/10.12669/pjms.36.2.1456 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Aim: The aim was to assess the presence of incidental-findings (IFs) on cone-beam computed tomography (CBCT) scans of faciomaxillary region with emphasis on gender and ethnicity. Materials and methods A retrospective analysis of incidental findings (IFs) in the maxillary sinus was performed. All CBCT-scans were performed using a Cone Beam 3D imaging system and examined using a software program. These images were taken for treatment planning for dental implant therapy of partially edentulous individuals. Four-hundred CBCT scans were retrospectively evaluated. Data regarding age, gender and ethnicity (Saudi Arabian, Egyptian, Filipino and Pakistani) of the patients was recorded. When P-value were lesser than 0.05, the difference was deemed significant. Results: Four hundred CBCT-based scans were investigated. The IFs were seen in 30.2%, 32.1%, 35.1% and 34.4% individuals belonging to the Egyptian, Saudi Arabian, Pakistani and Filipino ethnicities, respectively. Mucosal-thickening was more often identified in Saudi-Arabian (P < 0.05), Pakistani (P < 0.05) and Filipino males (P < 0.05) than females in the respective ethnic group. There was no difference in the identification of IFs (mucous retention cysts, opacifications, sinus septa and sinus floor discontinuation) related to the maxillary sinus region among males belonging to the Egyptian, Saudi-Arabian, Filipino and Pakistani ethnic groups. Interpretations and conclusion The CBCT-based technology is valuable resource for the identification of IFs.

Background: There is a debate regarding the significance of problem-based learning (PBL) model in educational systems. The aim of this study was to assess the awareness of dental students at the Princess Nourah Bint Abdulrahman University (PNU), Saudi Arabia, toward PBL. Methods: The present cross-sectional study was performed at the College of Dentistry, PNU, Riyadh, Saudi Arabia. An anonymous, standardized and self-administered questionnaire (based on nine items) coded as 1, 2, 3 and 4 was distributed to the first-, second-, third- and fourth-year undergraduate students, respectively, after a seminar that focused on the perceptions of PBL among the students at the end of the academic year 2017. The questionnaire was developed following an exhaustive search of indexed databases. Based on the students’ responses (yes/no) to the questions, group mean differences (95% CI) were computed and Pearson’s chi-squared test was used for data analysis. Cronbach’s alpha coefficient was also determined. The level of significance was set at P0.05). Conclusion: Perception of female undergraduate dental students at the PNU was inconclusive. Further studies are warranted in this regard.

The aim was to compare the in-vitro antibacterial effectiveness of two herbal extracts (a) Saussurea-costus (S. costus) and (b) Melaleuca-alternifolia (M. alternifolia) against Porphyromonas gingivalis (P. gingivalis), Streptococcus mutans (S. mutans) and Enterococcus faecalis (E. faecalis). Aqueous extracts from M. alternifolia were prepared by adding 2 grams of S. costus and M. alternifolia, respectively to 100 ml distilled water. Bacterial strains of P. gingivalis, E. faecalis and S. mutans were treated into 3 groups. In groups 1 and 2, bacterial strains were treated with aqueous extracts of S. costus and M. alternifolia, respectively. In the control-group, bacterial strains were exposed to distilled water. Antibacterial activity of the samples and nanoparticles was determined. The minimum-inhibitory-concentration (MIC) values were determined using the microdilution method. P < 0.01 was considered statistically significant. The MIC for all bacterial strains treated with S. costus was significantly higher than that of M. alternifolia (P < 0.001). There was no significant difference in MIC for strains of P. gingivalis, E. faecalis and S. mutans treated with S. costus. For bacterial strains treated with M. alternifolia, the MIC was significantly higher for P. gingivalis compared with E. faecalis and S. mutans strains (P < 0.01). There was no difference in MIC for E. faecalis and S. mutans strains treated with M. alternifolia. The in-vitro antibacterial efficacy of M. alternifolia is higher than S. costus against P. gingivalis, E. faecalis and S. mutans.