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Purpose: To determine the influence of iatrogenic gaps, type of cement, and time on microleakage of cast posts using spectrophotometer and glucose filtration measurements.Materials and Methods: Forty-eight single-rooted teeth were divided into eight groups of six teeth each. Teeth were instrumented and obturated, and a cast post was fabricated. In addition to two control groups (positive and negative), a total of six groups were prepared: In four groups, an artificial 2- to 3-mm gap was created between post and residual gutta percha (GP), and two groups were prepared with intimate contact between post and residual GP. Posts were cemented with either zinc phosphate cement or resin cement. Leakage through the post after 1, 8, 14, and 20 days was measured using a glucose penetration model with two different reading methods. Mixed analysis of variance tests were performed to analyze the data.Results: The presence of a gap between the apical end of the post and the most coronal portion of the GP remaining in the root canal after post space preparation increased microleakage significantly. However, microleakage was significantly less when the gap was refilled with GP compared to no gap. There was no difference in leakage between luting cements used.Conclusion: It was concluded that none of the cements were able to prevent microleakage. However, the addition of GP to residual GP did increase the sealing ability. [ABSTRACT FROM AUTHOR]

The aim of the study: to assess the shaping ability of the XPES file compared to that of the ProTaper Universal (PTU) file using micro-computed tomography (micro-CT). 19 mesial roots (with 2 separate canals) of mandibular molars were selected and scanned using micro-CT. The mesial root canals were divided into 2 groups: XPES files were used to instrument the mesiobuccal canals (n=19) while PTU files were used to instrument the mesiolingual canals (n=19). Instrumentation was performed in a water bath (37 C) to mimic body temperature. The roots were scanned using micro-CT before and after instrumentation. Pre- and post-instrumentation images were superimposed using Adobe Photoshop CC at 3 different levels (2, 4, and 6 mm from the apex). ImageJ 1.51s software was used to evaluate and measure cross-sectional area change of the canal and canal transportation in different directions. There was no statistically significant difference in the area change between the experimental groups. However, the mean mesial transportation in the PTU group was higher than that in the XPES group at 4 mm and 6 mm levels. XPES instrumentation might reduce the magnitude of canal transportation in the middle third region of mandibular molars mesial canals. [ABSTRACT FROM AUTHOR]

Introduction: Different irrigation protocols have been developed to improve the efficacy of root canal irrigants. The goal of this investigation was to compare several irrigation protocols for helping irrigation penetration into the dentinal tubule. Materials and methods: Fifty-five extracted single-rooted human lower premolar roots were instrumented to reach size 30 taper .04, sterilized, then inoculated with Enterococcus faecalis for 3 weeks. Teeth were then grouped according to the disinfection protocol into: group A (n=15): canals were disinfected with Diode Laser; group B (n=15): XP Endo Finisher was used for final irrigation; group C (n=15): needle irrigation, in addition to two control groups; D (n= 5): canals were irrigated with Saline and E (n=5), no bacteria being inoculated in the canals. The teeth were split into halves and stained with bacterial viability stain, then scanned by confocal laser scanning microscopy to measure the ratio of live vs dead bacteria in the dentinal tubules of the canals, Results and disscusion: A significant difference between the amount of live vs dead bacteria was found among all groups (p<0.05). The XP Endo finisher and Diode laser showed more dead bacteria at all levels. Conclusions: Sodium hypochlorite activation by Diode laser and XP Endo finisher improves disinfection of the root canal at all levels, especially at the apical part. Canals irrigated with the Diode Laser and XP Endo Finisher showed higher bacterial reduction of E. faecalis in dentinal tubules, compared with standard needle irrigation. [ABSTRACT FROM AUTHOR]

Objective. The investigation aims to compare antimicrobial efficacy of the extract of Commiphora molmol, against Enterococcus faecalis and Fusobacterium nucleatum, with sodium hypochlorite (NaOCl). Design. The dehydrated oleo-gum resin of Commiphora molmol was extracted by using 70% ethanol and was suspended in 99.8% dimethyl sulfoxide (DMSO) as a dissolving agent in a 1:2 volume to produce an aqueous solution at room temperature. Agar-well diffusion and broth microdilution methods assay were utilized to determine both the antimicrobial activity and minimum inhibitory concentration, of alcoholic extract of Commiphora molmol against E. faecalis and F. nucleatum. The values of the inhibition zones were determined based on the concentration of the investigated material. One hundred and forty extracted human premolar teeth were instrumented and immersed in bacterial suspension of E. faecalis or F. nucleatum (70 teeth in each species suspension). Prepared teeth were then immersed in the myrrh extract solution, 2.5% NaOCl, DMSO, or Cefotaxime and incubated for 30 and 60 minutes. Results. The largest inhibition zone diameter for both bacterial species was obtained by the 100mg/100μL concentration. The minimum inhibitory concentration (MIC) was 0.03mg/300μL for both E. faecalis and F. nucleatum. The minimum bactericidal concentration (MBC) results showed that 0.03mg/μL myrrh extract and 2.5% sodium hypochlorite significantly reduced bacterial growth at both 30 and 60 minutes of different treatments of root canals, compared to DMSO group (negative control) and the antibiotic group (positive group). Conclusion. Myrrh extract was proven to have considerable antibacterial activity against both F. nucleatum and E. faecalis. [ABSTRACT FROM AUTHOR]

The aims of this study were to develop, implement, and assess a contemporary dental curriculum that would be competitive internationally and take into consideration the specific needs of the community in a newly established all-female dental school in Saudi Arabia: Princess Nourah bint AbdulRahman University College of Dentistry (PNUCD). A six-step approach to curriculum development was used. Problem identification, general needs, and target needs were identified, and goals, objectives, and educational strategies were defined. The new curriculum emphasizes producing competent dentists focused on prevention and geared toward the needs of women and children. Leadership attributes, patient-centered care, and research are emphasized in the curriculum. Contemporary educational methods are used to implement the curriculum. In the assessment part of the study, evaluations of the curriculum by students, faculty, and external stakeholders (part-time instructors, program evaluators, and patients) have been mainly positive. Overall, PNUCD provided the opportunity to develop a curriculum that reflects the explosion of scientific knowledge, based on principles of modern educational theory in a unique cultural environment. [ABSTRACT FROM AUTHOR]

The aims of this study were to develop, implement, and assess a contemporary dental curriculum that would be competitive internationally and take into consideration the specific needs of the community in a newly established all-female dental school in Saudi Arabia: Princess Nourah bint AbdulRahman University College of Dentistry (PNUCD). A six-step approach to curriculum development was used. Problem identification, general needs, and target needs were identified, and goals, objectives, and educational strategies were defined. The new curriculum emphasizes producing competent dentists focused on prevention and geared toward the needs of women and children. Leadership attributes, patient-centered care, and research are emphasized in the curriculum. Contemporary educational methods are used to implement the curriculum. In the assessment part of the study, evaluations of the curriculum by students, faculty, and external stakeholders (part-time instructors, program evaluators, and patients) have been mainly positive. Overall, PNUCD provided the opportunity to develop a curriculum that reflects the explosion of scientific knowledge, based on principles of modern educational theory in a unique cultural environment.