Do dentists practice what they know? A cross-sectional study on the agreement between dentists' knowledge and practice in restoring endodontically treated teeth.

BACKGROUND: There are very few studies comparing dentists' knowledge in relation to their clinical approach despite the existence of a possible gap between what they know and what they do. AIM: To measure the agreement between knowledge and practice methods related to a selected clinical scenario involving the placement of an indirect post in endodontically treated teeth (ETT) among different types of practitioners. METHODS: An electronic questionnaire was emailed to members of the Saudi Dental Society. The questionnaire presented a clinical scenario of restoring a posterior ETT with an indirect post, core unit, and crown, followed by specific questions regarding knowledge and practice related to ten different treatment aspects such as who prepares the post space, technique, isolation, time, gap between gutta-percha, and time to cementation of the crown. Each question was presented twice for each aspect, once asking about their practice method and then what they thought was the correct practice (knowledge). The relationship between the participants' responses and their specialty and the agreement between the responses of knowledge and practice for each participant were analyzed by Pearson's chi-square test and Kappa. RESULTS: 203 completed questionnaires were analyzed. Most participants were 30 years old or younger (62.6%), and general dental practitioners (59%). When comparing the knowledge to the practice methods of each participant, nine out of ten aspects were of a "weak" level agreement or below (kappa < 0.59, p < 0.001). Only one aspect demonstrated a "strong" level of agreement (Kappa = 0.804), which was related to the duration of time between obturation and post space preparation in the presence of a periapical lesion. However, this strong agreement in the responses was not aligned with current evidence. There was also a significant difference among the responses of endodontists, restorative dentists and general practitioners in most of the aspects. CONCLUSION: Overall, there was a weak agreement between what practitioners know and do in most aspects of a selected clinical scenario involving the placement of an indirect post in posterior ETT. Moreover, the participant's specialty influenced their responses regarding both knowledge and clinical practice.

Bone morphology changes around two types of bone-level implants installed in fresh extraction sockets--a histomorphometric study in Beagle dogs.

BACKGROUND: Minimizing crestal bone loss following immediate implant placement is considered the most challenging aspect in implant therapy. Implant surface topography and chemical modifications have been shown to influence the success of Osseointegration. The Straumann Bone Level implant, featuring SLActive surface, has been introduced with the aim of enhancing bone apposition. Similarly, the OsseoSpeed implants from Astra Tech claim to have an enhanced osseointegration. Because of the specific features in the implant design, both companies claim that crestal resorption is minimal with these implants. OBJECTIVE: To evaluate the osseointegration and crestal bone level following immediate placement of Straumann Bone Level implant and OsseoSpeed implants in fresh extraction sockets in Beagle dogs. METHOD: The distal roots of the second, third and fourth premolars were extracted in both sides of the mandible. The distal roots were removed using a dental elevator. A total of 60 fixtures were installed in 10 Beagle dogs. Two types of implants were used: Straumann Bone-Level implants, which were 8 × 3.3 mm in size, and Astra Tech OsseoSpeed 3.5 S MicroThread implants, which were 8 × 3.5 mm in size. The histomorphometrical evaluation was performed at the end of 4- and 12-week healing. The implant-bone contact and bone volume percentage were assessed. RESULTS: The bone-to-implant contact (BIC) and the bone volume did not show any significant changes for both types of implants. The OsseoSpeed™ implants showed 67.4% and 65.3% BIC, respectively, at 4 and 12 weeks compared with 71.7 and 73.1 for the Straumann Bone-Level implants. The bone volume around both types of implants did not differ significantly at both time periods. The crestal bone resorption was observed for both types of implants. The first BIC at buccal side and lingual side of the implants also did not differ significantly for both implant systems. CONCLUSIONS: This study showed that Straumann Bone Level and OsseoSpeed implants induced similar bone response after immediate implantation at 4 and 12 weeks. The immediate implant placement resulted in peri-implant crestal bone-level changes for both types of implants.

Antibiofilm effect of different concentrations of silver nanoparticles combined with calcium hydroxide against Enterococcus faecalis biofilm: An ex vivo study.

This study aimed to evaluate the antibiofilm activity of different concentrations of silver nanoparticles (AgNPs) in combination with calcium hydroxide [Ca(OH)2] against Enterococcus faecalis biofilm. On an E. faecalis biofilm on dentin discs, the following medicaments were applied for 7 days (n = 13/group): 0.005% AgNPs+Ca(OH)2, 0.01% AgNPs+Ca(OH)2, 0.02% AgNPs + Ca(OH)2, Ca(OH)2 and saline/control. Specimens were stained with LIVE/DEAD® BacLight™ dye and analysed with confocal laser scanning microscopy. Proportion of dead bacteria was calculated and analysed. There was a significant reduction in E. faecalis biofilm in all medicament groups (43.5%, 49.1%, 69.1%, 48.7%) respectively, compared with control group (2.54%) (p < 0.001). The 0.02% AgNPs + Ca(OH)2 group demonstrated the most significantly superior antibiofilm effect, with no significant difference between remaining groups. In conclusion, combining 0.02% AgNPs enhanced the antibiofilm effect of Ca(OH)2 on E. faecalis biofilm compared with lower AgNPs concentrations.

Depression, anxiety and stress in dental students.

OBJECTIVES: To measure the occurrence and levels of depression, anxiety and stress in undergraduate dental students using the Depression, Anxiety and Stress Scale (DASS-21). METHODS: This cross-sectional study was conducted in November and December of 2014. A total of 289 dental students were invited to participate, and 277 responded, resulting in a response rate of 96%. The final sample included 247 participants. Eligible participants were surveyed via a self-reported questionnaire that included the validated DASS-21 scale as the assessment tool and questions about demographic characteristics and methods for managing stress. RESULTS: Abnormal levels of depression, anxiety and stress were identified in 55.9%, 66.8% and 54.7% of the study participants, respectively. A multiple linear regression analysis revealed multiple predictors: gender (for anxiety b=-3.589, p=.016 and stress b=-4.099, p=.008), satisfaction with faculty relationships (for depression b=-2.318, p=.007; anxiety b=-2.213, p=.004; and stress b=-2.854, p<.001), satisfaction with peer relationships (for depression b=-3.527, p<.001; anxiety b=-2.213, p=.004; and stress b=-2.854, p<.001), and dentistry as the first choice for field of study (for stress b=-2.648, p=.045). The standardized coefficients demonstrated the relationship and strength of the predictors for each subscale. To cope with stress, students engaged in various activities such as reading, watching television and seeking emotional support from others. CONCLUSIONS: The high occurrence of depression, anxiety and stress among dental students highlights the importance of providing support programs and implementing preventive measures to help students, particularly those who are most susceptible to higher levels of these psychological conditions.