Self-reported preparedness of final year undergraduate dental students and interns in Saudi Arabia: a multi-institutional study.

BACKGROUND: Contemporary undergraduate dental education aims to equip the dental students with clinical competence, empathy, and professionalism to enable them to deliver safe and effective dental care to the communities. The purpose of this study was to assess the self-reported preparedness of final year dental students and interns at three Saudi dental institutions, using the pre-validated Dental Undergraduates Preparedness Assessment Scale (DU-PAS). METHODS: A cross-sectional study design was employed to assess the self-reported preparedness of the participants using the DU-PAS. Following ethics approval, a probability sampling technique was used to recruit undergraduate dental students and interns from three dental institutions in Saudi Arabia. The data was collected online on Google Forms and all participants provided their consent to participate in the study prior to providing their responses to DU-PAS. RESULTS: Responses were received from 397 participants including 171 males and 226 females yielding a response rate of 60.3%. The total mean score of the participants was 81.85 ± 13.11. Although higher scores were reported in males, the interaction between gender and DU-PAS scores were not significant. Interaction between DU-PAS scores and stage of education showed significant effect of the stage of education with interns reporting higher overall scores. The participants reported that they were able to perform most clinical procedures independently. However, low confidence was reported in performing multi-rooted endodontics, fabrication of removable dentures and orthodontic assessment. The participants also expressed their confidence in a wide range of behavioural attributes related to communication, teamworking and professionalism. However, lack of experience was noted in referral for oral cancer, interpreting research, and evaluation of new dental products using an evidence-based approach. CONCLUSION: The study provides useful insights into the self-reported preparedness of undergraduate dental students and interns in three dental institutions. While the overall preparedness of the participants was comparable to their international peers, the findings underscore the need for further enhancements to the teaching and training of undergraduate students particularly in multirooted endodontics, removable prosthodontics and orthodontics.

Comparison of Efficacy of Lidocaine and Articaine as Inferior Alveolar Nerve Blocking Agents in Patients with Symptomatic Irreversible Pulpitis: Randomized Controlled Trial.

Background and Objectives: Lidocaine Hydrochloride has been the standard choice for local anesthesia in dentistry and Articaine's unique structure and growing popularity make it a viable alternative. Due to contradictory results in prior research and a scarcity of trials conducted in the Pakistani population, this study aims to compare the anesthetic efficacy of Lidocaine with Articaine for inferior alveolar nerve blocks in patients with symptomatic irreversible pulpitis. Materials and Methods: This double-blinded, randomized controlled trial included 152 patients who were selected by consecutive non-probability sampling. The participants included patients who presented with symptomatic irreversible pulpitis in mandibular posterior teeth (molars and premolars) and depicted normal apical tissue radiographically. The patients were equally and randomly divided into two groups. The control group received 2% Lidocaine Hydrochloride injections, and the experiment group received 4% Articaine Hydrochloride injections. Participants scored their pain on the HP-VAS both before and after the administration of anesthesia. A value of 54 mm or less on the scale indicated effective anesthesia. The data obtained were analyzed using SPSS. Chi-square test was applied to analyze data for statistical significance. Results: There was no statistically significant difference in the efficacy of the two anesthetic agents. During access cavity preparation, Lidocaine demonstrated a success rate of 93%, whereas Articaine exhibited a slightly higher success rate of 97%. During initial instrumentation, the success rates for Lidocaine and Articaine were 72% and 71%, respectively. This suggests that both Lidocaine and Articaine were effective in achieving anesthesia during the dental procedure in patients with symptomatic irreversible pulpitis, with Articaine showing a slightly better success rate, although the difference was not statistically significant. Conclusions: The anesthetic efficacy of Articaine is similar to that of lidocaine in subjects with symptomatic irreversible pulpitis. Hence, Articaine can serve as an alternative to Lidocaine for local anesthesia administration in dentistry.

A Cone Beam Computed Tomography-Based Investigation of the Frequency and Pattern of Radix Entomolaris in the Saudi Arabian Population.

Background and Objectives: An understanding of the anatomical complexity of teeth is a significant factor for a successful endodontic treatment outcome. The aim of this study was to explore the frequency and pattern of distribution of radix entomolaris (RE) in mandibular first molars (MFMs) of a Saudi Arabian subpopulation using CBCT scans. Materials and Methods: This study was conducted at dental clinics of Qassim University from February to May 2023 by evaluating CBCT scans that were previously obtained for diagnostic purposes. Scans of Saudi national patients with bilaterally present MFMs and fully formed root apices were included. Conversely, scans with one/or two missing MFMs, MFMs with incomplete root apices, full- or partial-coverage prosthesis, endodontic treatment, and associated radicular resorption were excluded from study. A total of 303 CBCT scans with 606 bilateral MFMs were analyzed by two calibrated evaluators for the presence of, and type according to Song's typolgy of RE. The data were analyzed using SPPS-24. The descriptive variables were documented as frequencies and percentages. The chi-square test was used to determine the association between the prevalence of RE with the gender, jaw side and age group. Both inter-rater and intra-rater agreements were estimated for detecting and classifying RE using Cohen's kappa test. Results: The sample had 63.7% males and 36.3% females. The prevalence of RE was 6.6%, with Song's type III (57.5%) as the most common variant. Absolute agreement was noted between the raters about the presence of RE and very strong agreement was noted for the classification of the RE. Conclusions: RE is an uncommon finding among the mandibular first molars of the Saudi population without any gender and quadrant predilection. The clinicians' knowledge of the presence and Song's type of RE may contribute towards the enhancement of endodontic treatment outcomes.

Fracture Load of CAD/CAM Fabricated Cantilever Implant-Supported Zirconia Framework: An In Vitro Study.

The fracture resistance of computer-aided designing and computer-aided manufacturing CAD/CAM fabricated implant-supported cantilever zirconia frameworks (ISCZFs) is affected by the size/dimension and the micro cracks produced from diamond burs during the milling process. The present in vitro study investigated the fracture load for different cross-sectional dimensions of connector sites of implant-supported cantilever zirconia frameworks (ISCZFs) with different cantilever lengths (load point). A total of 48 ISCZFs (Cercon, Degudent; Dentsply, Deutschland, Germany) were fabricated by CAD/CAM and divided into four groups based on cantilever length and reinforcement of distal-abutment: Group A: 9 mm cantilever; Group B: 9 mm cantilever with reinforced distal-abutment; Group C: 12 mm cantilever; Group D: 12 mm cantilever with reinforced distal-abutment (n = 12). The ISCZFs were loaded using a universal testing machine for recording the fracture load. Descriptive statistics, ANOVA, and Tukey's test were used for the statistical analysis (p < 0.05). Significant variations were found between the fracture loads of the four ISCZFs (p = 0.000); Group-C and B were found with the weakest and the strongest distal cantilever frameworks with fracture load of 670.39 ± 130.96 N and 1137.86 ± 127.85 N, respectively. The mean difference of the fracture load between groups A (810.49 + 137.579 N) and B (1137.86 ± 127.85 N) and between C (670.39 ± 130.96 N) and D (914.58 + 149.635 N) was statistically significant (p = 0.000). Significant variations in the fracture load between the ISCZFs with different cantilever lengths and thicknesses of the distal abutments were found. Increasing the thickness of the distal abutment only by 0.5 mm reinforces the distal abutments by significantly increasing the fracture load of the ISCZFs. Therefore, an increase in the thickness of the distal abutments is recommended in patients seeking implant-supported distal cantilever fixed prostheses.

Students' self-assessment: a learning tool and its comparison with the faculty assessments.

OBJECTIVE: This study compared the student's self-grades versus the examiners grades, inter examiner grades and grades of anterior with posterior teeth in a preclinical prosthodontic course. METHODS: 75 students and 2 examiners participated in the study. The students prepared one anterior (upper central incisor) and one posterior (lower first molar) teeth for full veneer crowns in allocated time of 2 hours and 30 minutes. After the preparations, the students self-graded their preparations based on criteria-based evaluation forms. The examiners also completed the grading for the prepared teeth. All the grades were recorded, comparisons were made using SPSS version 21 and results tabulated. RESULTS: The means of grades (8.32) by the students themselves were found to be higher compared to the examiners grades (7.3) for the anterior as well as posterior teeth. Comparison of the grades for the anterior/posterior teeth and the overall grades showed a statistically significant difference (p=0.000). A moderate correlation (0.399) and a strong correlation (0.601) were found between the grades of the faculty and the students for the anterior and posterior teeth respectively. The overall grading for the anterior and posterior teeth by the two faculty members showed no statistically significant difference (p=0.053) and a very strong correlation (0.784). The results of the test showed a significant difference (p=0.001) between the overall grading for anterior and posterior teeth. CONCLUSION: Students tended to grade their teeth preparations higher compared to the examiner grades, inter examiner variation in the grades existed and the grades of the anterior teeth were higher compared to the posterior teeth.

Comparison of Shade of Ceramic with Three Different Zirconia Substructures using Spectrophotometer.

OBJECTIVE: This study assessed how changing the Zirconia (Zr) substructure affected the color samples after they have been overlaid by the same shade of veneering ceramic. MATERIALS AND METHODS: Three commercial Zr materials were tested in this study: Prettau(®) Zirconia (ZirKonZahn, Italy), Cercon (Dentsply, Germany) and InCoris ZI (Sirona, Germany). For each system, 15 disk-shaped specimens (10 × 1 mm) were fabricated. Three shades of A1, A2 and A3.5 of porcelain (IPS e.MaxCeram, IvoclarVivadent, USA) were used for layering the specimens. Five specimens from each type of Zr were layered with same shade of ceramic. Color measurements were recorderd by a spectrophotometer Color-Eye(®) 7000A (X-Rite, Grand Rapids, MI). Mean values of L, a, b color coordinates and ΔE were recorded and comparisons were made. RESULTS: Differences in the ΔE were recorded for the same porcelain shade with different Zr substructures and affected the color of the specimens (p < 0.01, ANOVA). The maximum difference between the ΔE values for the A1, A2 and A3.5 shades with three types of Zr substructures was found to be 1.59, 1.69 and 1.45 respectively. Multiple comparisons of the ΔE with PostHoc Tukey test revealed a statistically significant difference (p < 0.05) between the three types of Zr, except between Type 2 Zr and Type 3 Zr for the Shade A1. The mean values of L, a, b and ΔE for the Prettau(®) Zirconia substructure were found to be the least among the three types. CONCLUSIONS: The brand of Zr used influences the final color of the all ceramic Zr based restorations and this has clinical significance.

Evaluation of medicinal interventions for the management of oral submucous fibrosis: a systematic review of the literature.

Oral submucous fibrosis is a chronic, progressive scarring disease associated with both significant morbidity including pain and limited mouth opening and an increased risk for malignancy. This systematic review evaluated the different medicinal (i.e. nonsurgical) interventions available for the management of oral submucous fibrosis. An automated literature searches of online databases from January 1960 to December 2013 were performed and only studies with high level of evidence based on the guidelines of the Oxford Centre for evidence-based medicine were selected. Thirteen studies (3 randomized controlled trials and 10 clinical trials/controlled clinical trials) were included and drugs like steroids, hyaluronidase, human placenta extracts, chymotrypsin and collagenase, pentoxifylline, nylidrin hydrochloride, iron and multivitamin supplements including lycopene were used. There is a clear lack of evidence on the available drug treatment for oral submucous fibrosis and further high quality randomized controlled trials are needed to evaluate the different therapeutic agents.

Patient's satisfaction with the dental care provided by dental students.

BACKGROUND: The success of an oral health service can be assessed by the degree of satisfaction of its patients. The objective of this study was to evaluate patient satisfaction following comprehensive dental treatment provided by final year dental students at college of dentistry, King Saud University, Riyadh, Saudi Arabia and to correlate the level of patient satisfaction with their post-treatment oral hygiene maintenance. METHODS: The required information for this cross-sectional was collected from patients using a self-answered questionnaire. A five point Likert scale was used (Strongly agree, agree, neither, disagree and strongly disagree) to evaluate the level of patient satisfaction. Clinical examination included assessment of oral hygiene status using 0111-S (Oral Hygiene Index-Simplified). RESULTS: Four hundred & forty-six patients who received comprehensive dental treatment at the student clinics during the past two years were contacted out of which 86 patient's (81% males and 19% females) participated. The overall patient's satisfaction score of 68.67±6.85 was highly satisfactory. The mean OHI-S score was 2.21±1.68. This showed a good to moderate level of oral hygiene among the participating patients. No statistically significant difference was found for the overall patient satisfaction score in relation to the age, gender, nationality and educational level. The post treatment oral hygiene status was significantly better in female patients compared to males. There was no statistically significant difference in OHI-S scores in relation to age, nationality and education level. The patient satisfaction scores and OHI-S score showed no correlation. CONCLUSION: The patients treated by the dental students at college of dentistry were highiy satisfied with their treatment. A good to moderate level f post treatment oral hygiene among the participating patients was recorded according to the

The Surface Roughness of Contemporary Indirect CAD/CAM Restorative Materials That Are Glazed and Chair-Side-Finished/Polished.

The surface roughness (Ra) of indirect computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated dental restorations is crucial for their long-term durability. This study intended to evaluate the Ra of five different types of contemporary indirect CAD/CAM restorative materials with varying compositions that were glazed and finished/polished. A total of 75 specimens, disc-shaped (10 mm × 2 mm), were obtained from five materials (n = 15) (Tetric CAD, IPS e.max CAD, IPS e.max ZirCAD, CELTRA Duo, and Vita Enamic) and fabricated by CAD/CAM. One of the two surfaces for each specimen was subjected to glazing, while the other surface was subjected to finishing/polishing. The Ra of the two surfaces in micrometers (µm) was evaluated using a Profilometer, while the surface topography was examined using a scanning electron microscope. Using SPSS, the Kruskal-Wallis, post hoc Conover, and Mann-Whitney tests were used to statistically evaluate the data. A comparison of the Ra for the finished/polished surfaces of the five test materials showed significant differences (p < 0.0001). Among the finished/polished surfaces, the mean rank values of Vita Enamic were significantly higher than the other four test materials (p < 0.0001). A comparison of the Ra of glazed surfaces among the five study materials revealed significant differences (p < 0.0001). The Ra for the IPS e.max ZirCAD material was significantly higher than the rest of the four materials (p < 0.001). A comparison of the Ra for two types of surface conditioning within each of the five test materials showed a significant difference (p < 0.05). Only for IPS e.max ZirCAD was the Ra of the glazed surface significantly higher than the finished/polished surface (p < 0.0001). Significant variations in the surface roughness (Ra) were exhibited between the finished/polished and glazed surfaces of the five test materials. Hybrid ceramics showed the highest Ra values for the finished/polished surfaces, and zirconia exhibited the highest Ra values among the glazed surfaces among the tested materials. The Ra values of either finished/polished or glazed surfaces of the test materials were within the clinically acceptable range (0.2-0.5 µm), except for the glazed surface of the zirconia ceramics (0.84 µm).

Comparative in-vivo bond failure rate of orthodontic brackets when bracket base is treated with micro-abrasive blasting vs. acid etching: eighteen month randomized control trial and scanning electron microscope study.

Background: The aim of this study was threefold. Firstly, it aimed to introduce and detail a novel method for chemically etching the bases of stainless-steel orthodontic brackets. Secondly, the study sought to investigate the structural alterations within the brackets' microstructure following chemical etching compared to those with sandblasted bases, using electron microscopy analysis. Lastly, the study aimed to evaluate and compare the long-term durability and survivability of orthodontic brackets with chemically etched bases versus those with sandblasted bases, both bonded using the conventional acid etch technique with Transbond XT adhesive, over an 18-month follow-up period. Methods: The study was a randomized clinical control trial with triple blinding and split-mouth study design and consisted of two groups. The brackets in the sandblasted group were prepared by sandblasting the intaglio surface of the base of the bracket with 50 µm SiO2 particles. Hydrofluoric acid was used to roughen the base in the acid-etched group. The bases of the brackets were viewed under an electron microscope to analyze the topographical changes. Results: A total of 5,803 brackets (3,006 acid-etch, 2,797 sandblasted) in 310 patients were bonded, in a split-mouth design by the same operator. The patients were followed for 18 months. The failure rate of 2.59% and 2.7% was noted in an acid-etched and sandblasted group, respectively. There was a close approximation of curves in the Kaplan-Meier plot, and the survival distribution of the two groups in the log-rank (Mantel-Cox) test was insignificant; x2 = 0.062 (P value = 0.804). Conclusion: Acid etching if the bases of the brackets can be used as an alternative to sandblasting furthermore acid etching can be performed on the chair side.

Evaluation of the Effect of Electronic Cigarette Devices/Vape on the Color of Dental Ceramics: An In Vitro Investigation.

The use of vaping or electronic cigarette devices (ECDs) has recently increased as an alternative to conventional tobacco smoking products. By recording the CIELAB coordinates (L*a*b*) and computing the total color difference (ΔE) values using a spectrophotometer, the effect of ECDs on contemporary aesthetic dental ceramics was investigated in this in-vitro study. A total of seventy-five (N = 75) specimens from five different (n = 15) dental ceramic materials (Pressable ceramics (PEmax); Pressed and layered ceramics (LEmax); Layered zirconia (LZr); Monolithic zirconia (MZr) and Porcelain fused to metal (PFM)) were prepared and exposed to aerosols produced by the ECDs. The color assessment was performed using a spectrophotometer at six time intervals (0 = baseline; 250-puff exposures; 500-puff exposures; 750-puff exposures; 1000-puff exposures; 1250-puff exposures; and 1500-puff exposures). By recording L*a*b* and computing total color difference (ΔE) values, the data were processed. A one-way ANOVA and Tukey procedure for pairwise comparisons were used to assess color differences between tested ceramics (p < 0.05). All test materials demonstrated significant color differences (ΔE) after exposure to vaping (p < 0.05). The LZr group displayed noticeably high ΔE values at all the distinct puff exposure intervals, with the highest ΔE value of (13.67) after 1500 puffs. The lowest (ΔE) values were observed in the PFM group after 250 and 500 puffs (0.85 and 0.97, respectively). With the exception of the group PEmax (p = 0.999), all groups produced readings of "ΔE" that indicated significant differences (p < 0.05) at various degrees of puff exposures. ECDs can noticeably alter the color of the dental ceramics affecting the esthetics of the patients. All the materials tested demonstrated significant color changes (ΔE > 3.33) above the clinically acceptable threshold, except for the PFM and PEmax group (ΔE < 3.33) which showed color stability after exposure to the ECDs.

Dental students' academic performance before and after the Covid-19 pandemic: A retrospective analysis.

Delivering quality education to students with fair assessment strategies is a key indicator of an excellent educational institution. The present study explored the impact of the COVID-19 pandemic on the academic performance of dental students in terms of the evaluations/grades awarded to them before and during the pandemic. The targeted groups were dental students, studying in the third year of 2018-2019 and 2020-2021 academic years. The sample size included all male and female students who enrolled and completed the following courses: pre-clinical fixed prosthodontics (SDS333), pre-clinical removal prosthodontics (SDS323), clinical operative dentistry-1 (RDS313), and pre-clinical endodontics (RDS323). Evaluations for students who did not complete the requirements were not included in the statistical analysis. Paired sample statistics were used for comparisons between the different groups at p < 0.05. Results revealed statistically significant differences (p ≤ 0.05) for all the course pairs. It was found that students' grades for all the courses during the pandemic year were higher compared to the grades before the pandemic. While female students demonstrated the highest mean difference (6.13) before and during the pandemic year for RDS323, males demonstrated the highest mean difference (8.14) for SDS323. However, both male and female students demonstrated the lowest mean difference (0.25 and 2.03, respectively) for SDS333. The grades were higher during the COVID-19 pandemic. Overall, female students achieved higher grades than male students.

Patients' Satisfaction and Oral Health-Related Quality of Life of Edentulous Patients Using Conventional Complete Dentures and Implant-Retained Overdentures in Saudi Arabia.

The aim of this study was to compare patients' satisfaction and quality of life (QoL) when using implant overdentures vs. conventional dentures. The QoL of Saudi patients who were provided mandibular implant-supported overdentures was assessed using a structured questionnaire. Overall satisfaction; ability to speak, eat, and chew food; comfort; esthetics; stability; and satisfaction of general oral health were measured. A total of 48.3% vs. 6.9% were, overall, very satisfied with their implant overdentures and conventional dentures, respectively. A total of 37.9% of the patients were very satisfied regarding speaking with their implant overdentures vs. 17.2% with conventional dentures. Furthermore, 41.4% were very comfortable with their implant overdentures vs. 5.2% were very comfortable using conventional dentures. However, only 15.5% were very satisfied with the esthetics of the conventional dentures compared to 43.1% being satisfied with implant overdentures. Only 1.7% were very satisfied with the stability of conventional dentures vs. 44.8% being satisfied using implant overdentures. About 8.6% of the candidates were very satisfied regarding chewing food with conventional dentures vs. 36.2% being very satisfied using implant overdentures. Approximately 10.3% were very satisfied with their general oral health using conventional dentures compared to 29.3% being very satisfied using implant overdentures. Mandibular implant overdentures had a strong impact on patients' quality of life over conventional complete dentures and should be considered the minimum standard of care provided to completely edentulous patients.

An Evaluation of the Usefulness of YouTube® Videos on Crown Preparation.

BACKGROUND: You Tube is one of the most commonly used online sources for sharing information and knowledge. Academic topics or clinical data shared on this platform is not peer reviewed or evaluated by subject specialists for accuracy. No study was found in the literature examining the validity of crown preparation videos available at this platform. OBJECTIVE: To evaluate the authenticity of the content and quality of the crown preparation videos uploaded on the YouTube. METHODS: The systematic search for YouTube videos was carried out over a period of one year from January 2020 until February 2021. The keywords or phrases and tags used were crown preparation, PFM crown preparation, all ceramic crown preparation, and dental crown preparation. The videos were shortlisted on the basis of inclusion and exclusion criteria to select educationally useful videos in terms of content and quality. RESULTS: Three subject specialists evaluated the videos on crown preparation three times to shortlist only 12 (11%) educationally useful videos out of 109 relevant videos. These 12 videos met the preset inclusion criteria. CONCLUSION: Although YouTube is the most popular social media platform used as the source of information by the students, the majority of uploaded content lacks authenticity. This study found that crown preparation videos uploaded by the faculty members or subject specialists can be considered as the reliable source.

Push-Out Bond Strength of Endodontic Posts Cemented to Extracted Teeth: An In-Vitro Evaluation.

(1) Background: An ideal bond strength between endodontic posts and root canal dentin is essential for optimal retention and good prognosis. This study aimed to evaluate the push-out bond strength (PBS) of prefabricated fiber and metal posts, luted with resin cement to natural dentin. (2) Methods: Extracted premolars with similar root dimensions were assigned into two groups of 30 each for the metal and fiber posts. Teeth were mounted in acrylic blocks exposing 2 mm of the coronal root. Teeth were subjected to endodontic treatment and post-space preparations. Two groups were further subdivided into three sub-groups (n = 10) according to the size of the posts (# 4, 5 and 6). Posts were cemented with resin cement. Specimens were sectioned into 4 mm slices and subjected to the PBS test. (3) Results: The mean PBS was similar for the metal and fiber posts bonded with resin cement, showing a statistically significant result. An increase in post size increased the bond strength initially, but a further increase in size did not show any marked difference. A total of 71.66% of tested specimens failed with the adhesive failure mode. (4) Conclusions: Metal posts showed slightly higher retention compared to the fiber posts, although the p-value was similar for both types. An increase in the size of posts showed increased retention. The most common mode of failure was adhesive failure between cement and dentin.

Undergraduate Dental Students' And Instructors' Perceptions About The Quality Of Clinical Feedback.

BACKGROUND: Feedback is an essential component of the clinical skills development of dental students. The clinical training is a complex integration of knowledge, psychomotor skills, behaviour and clinical communication skills under stress for both instructor and student. This study aimed to investigate the perceptions of undergraduate dental students and their instructors on the quality of clinical feedback. METHODS: The current cross-sectional observational study was conducted at the Department of Operative Dentistry and Endodontics, Riphah International University, Islamabad from August to December 2019. A self-administered questionnaire was used to collect responses from final year undergraduate dental students and faculty. The questionnaire comprised of 13 items, subdivided into six categories, targeting the various aspects of clinical feedback. SPSS 23 was utilized to analyse the data. Descriptive statistics were tabulated and data was analysed using the Mann-Whitney test (p<0.05) for differences between the two cohorts. RESULTS: The mean age of the 64 students who responded was 24±0.8 years. Students' male to female ratio was 1:1.56, while for the 18 instructors the ratio was 1:1. Good agreement between the students and instructors was shown for items related to personal dignity and empathy. Moderate agreement was found for items covering the domains of time, understanding, comfort level, professionalism, and self-assessment. The disagreement was observed for the items associated with conflicting feedback, conflict satisfaction, and effective communication. CONCLUSIONS: Incongruousness existed between the dental students and instructors, about the quality of clinical feedback provided to the dental students. Communication between the instructors and learners must be promoted to increase the level of understanding of the feedback given by the clinical instructors.

Comparison of the Fracture Resistance and Fracture Mode of Contemporary Restorative Materials to Overcome the Offset of Mandibular Implant-Supported, Cement-Retained Crowns.

BACKGROUND: The purpose was to compare the fracture resistance and the mode of failure of different contemporary restorative materials to restore implant supported, cement-retained mandibular molars. METHODS: Two 5 × 10 mm titanium dental implants were mounted in resin blocks and prefabricated titanium and zirconia abutments were connected to each implant. Each implant received forty crowns resembling mandibular first molars. The specimens were divided into four groups (n = 10/group) for each abutment according to the type of material; Group A: porcelain fused to metal crowns; Group B: monolithic zirconia crowns; Group C: zirconia coping with ceramic veneer; Group D: all ceramic lithium disilicate crowns. Specimens were cemented to the abutments, mounted into a universal testing machine, and vertical static load was applied at a speed of 1 mm/min. The test stopped at signs of visual/audible fracture/chipping. Fracture resistance values were analyzed using ANOVA and Tukey's tests (α ≤ 0.05). The modes of failure were visually observed. RESULTS: A statistically significant difference (p < 0.001) of the fracture resistance values among tested groups was found. The group that showed the highest fracture resistance was Group A for both the titanium and the zirconia abutments (3.029 + 0.248 and 2.59 ± 0.39, respectively) while Group D for both abutments (1.134 + 0.289 and 1.68 ± 0.13) exhibited the least resistance. CONCLUSIONS: Fracture resistance and fracture mode varied depending on type of restorative material. For both titanium and zirconia abutments, porcelain fused to metal showed the highest fracture resistance values followed by monolithic zirconia.

Comparing the Ability of Various Resin-Based Composites and Techniques to Seal Margins in Class-II Cavities.

Background: Resin-based composites (RBCs) provide excellent esthetics but the marginal micro-leakage in the proximal cavities remains a major concern. The aim of the present study was to assess the ability of various dental RBCs and techniques utilized for sealing deep dentin margin in class-II cavities. Methods: Box-cavities (class-II) on the distal and mesial surfaces of extracted (premolar) teeth were prepared with a gingival margin placed 1mm apical to the cemento-enamel junction. Teeth with prepared class II cavities were randomly divided into four study groups according to the type of restorative materials (conventional RBC; bulk-fill RBC; conventional RBC lined with flowable RBC and conventional RBC lined with resin-modified glass-ionomer-cement (GIC) as open sandwich-technique). Each group was further subdivided into a total-etch subgroup in which a separate etching step was performed before applying the bonding agent and a self-etch subgroup in which a self-etch adhesive system was used (n = 10). For each group, cavities were restored using the respective restorative materials and techniques, subjected to 1000 thermocycles, and placed in the methylene-blue dye. The specimen teeth were sectioned for further microscopic examination for micro-leakage. Results: The least dye penetration values were reported for group 4 (GIC) followed by the group Bulk-fill using the self-etch adhesive system (group 2b). The highest dye penetration was reported for the group Bulk-fill using the total-etch adhesive system (2a), followed by the group conventional RBC using the total-etch adhesive system). The total-etch adhesive system had significantly greater micro-leakage compared to the self-etch adhesive system (1a) (p = 0.026). Conclusions: The self-etch adhesive system significantly reduced the micro-leakage compared to the total-etch system. Bulk-fill RBC when bonded with the self-etch adhesive provided good marginal sealing ability comparable to open sandwich-technique using GIC.

Regenerative Therapy Modality for Treatment of True Combined Endodontic-Periodontal Lesions: A Randomized Controlled Clinical Trial.

The aim of this in-vivo study was to evaluate/compare the clinical periodontal parameters in patients with true combined endo-perio lesions (EPL), treated with gutta-percha (GP) and mineral trioxide (MTA) as an obturation material alone and with addition of bone grafting in such lesions. 120 Saudi patients (mean age = 41yrs) diagnosed with true combined EPL participated in this study. Group I (control group, n = 30) was treated with conventional endodontic treatment using GP for obturation. Group II (n = 30) was treated with conventional endodontic treatment using MTA for obturation. Group III (n = 30) was treated with conventional endodontic treatment using GP for obturation + grafting procedure to fill the bony defect. Group IV (n = 30) was treated with conventional endodontic treatment using MTA for obturation + grafting procedure to fill the bony defect. Clinical parameters (Pocket depth (PD); Clinical attachment loss (CAL); keratinized tissue width (KTW); gingival phenotype (G.Ph.) and Cone Beam Computed Tomography Periapical Index (CBCTPAI)) were recorded and compared at baseline, 3, 6, 12 months' interval. For the groups III and IV, CBCTPAI showed significant difference (p < 0.0001) with the other groups at 6 months and 1-year interval. The group with MTA + bone graft showed 76% and 90% patients with 0 score at 6 months and 1-year follow-up, respectively. Comparison of mean values of PD among study groups at 3 months, 6 months and 1 year showed significant difference at 3 months, whereas the mean PD values of subjects in GP + bone graft showed significantly higher PD values than other 3 groups (p = 0.025). Use of GP and MTA for root canal obturation along with periodontal therapy and bone augmentation helps in resolving complex endo-perio lesions. Bone grafting in addition to obturation with MTA was found to be the best treatment strategy in management of EPL cases and is recommended for clinicians who are treating EPL patients.

Shear Bond Strength of Veneered Zirconia Repaired Using Various Methods and Adhesive Systems: A Comparative Study.

The aim of the present study was to investigate the shear bond strength of five different repair methods and adhesive systems for zirconia (Zr) cores layered with feldspathic porcelain. Seventy-five Zr specimens (10 × 10 × 4 mm3) were prepared, sintered, layered with 2 × 10 × 10 mm3 of feldspathic porcelain, and fired. The ceramic was fractured, and the load recorded using a shear-bond test. Specimens were thermocycled and randomly divided into 5 groups (n = 15/group) based on the repair methods. Composite repair blocks with similar dimensions to the layered ceramic (2 × 10 × 10 mm3) were built according to each repair method. Shear bond strength testing of the specimens with composite built up was carried out using a universal testing machine (Instron®5960, Massachusetts, USA). The shear bond strengths of the adhesive interface between repaired composite and the Zr were recorded for all the test groups. The fractured specimens' surfaces were examined under a scanning electron microscope (Jeol, Musashino, Akishima, Tokyo, Japan) for evaluation of the type of failure and surface characteristics. Shear bond strength of the veneered ceramic bonded to the Zr for all the test groups was non-significant (ANOVA, p = 0.062). Shear bond strength after the repair revealed significant differences (ANOVA, p = 0.002). Group-C (13.79 ± 1.32) and Group-D (9.77 ± 4.77) showed the highest and lowest shear bond strength values, respectively. Paired Sample T-tests showed significantly lower values (p = 0.000) for the repaired (composite) Zr compared to the layered (ceramic) Zr. Multiple comparisons revealed differences (significant) between the shear bond strength of Group-D with Groups A (p = 0.010) and C (p = 0.003, Post Hoc Tukey test). The repair methods tested showed variations in their respective shear bond strengths. Complete ceramic/zirconia repair systems showed better bonding between the repaired composite and Zr core. The mean shear bond strength for the repaired fractured layered Zr showed acceptable outcomes in terms of clinical perspective, but was, however, unpredictable.