Perception of Minimum Interventional Dentistry among Dental Undergraduate Students and Interns.

Background: The philosophy of minimum interventional dentistry (MID) is to integrate prevention, remineralization, and minimal intervention for the placement and replacement of restorations. All branches of dentistry play an important role in practicing MID, and their primary goal is to realize that any restoration is of less biological significance than the healthy original tissue Objectives: The objective of this study was to assess the perception of MID among dental undergraduate students and interns in terms of knowledge, attitude, and practice at the College of Dentistry. Materials and Methods: This cross-sectional study was conducted among undergraduate students and interns at the College of Dentistry, Qassim University, Saudi Arabia. A self-administered questionnaire was distributed, which included basic demographic profiles and questions about the knowledge, attitude, and practices toward MID. The data were tabulated in MS Excel, and all statistical analyses were performed using SPSS version 21. Results: A total of 163 dental students were recruited, with senior students comprising 73% and interns comprising 27%. Male students were slightly more prevalent (50.9%) than female students (49.1%). About 37.6% of participants received training about MID during educational courses, while 10.3% received it during their internship. A statistical test revealed that the prevalence of interns who were trained in performing MID was significantly higher (p < 0.001). Conclusions: The majority of the participants demonstrated proper knowledge, attitude, and practice in different aspects of MID. Interns reported a higher rate of knowledge, attitude, and practice in MID compared to undergraduate students. However, more education and hands-on training about MID concepts during the college curriculum are necessary to attain better knowledge, attitude, and practices that could be useful for more conservative clinical practice.

Mechanical Properties of the Modified Denture Base Materials and Polymerization Methods: A Systematic Review.

Amidst growing technological advancements, newer denture base materials and polymerization methods have been introduced. During fabrication, certain mechanical properties are vital for the clinical longevity of the denture base. This systematic review aimed to explore the effect of newer denture base materials and/or polymerization methods on the mechanical properties of the denture base. An electronic database search of English peer-reviewed published papers was conducted using related keywords from 1 January 2011, up until 31 December 2021. This systematic review was based on guidelines proposed by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search identified 579 papers. However, the inclusion criteria recognized 22 papers for eligibility. The risk of bias was moderate in all studies except in two where it was observed as low. Heat cure polymethyl methacrylate (PMMA) and compression moulding using a water bath is still a widely used base material and polymerization technique, respectively. However, chemically modified PMMA using monomers, oligomers, copolymers and cross-linking agents may have a promising result. Although chemically modified PMMA resin might enhance the mechanical properties of denture base material, no clear inferences can be drawn about the superiority of any polymerization method other than the conventional compression moulding technique.

Graphene oxide-based experimental silane primers enhance shear bond strength between resin composite and zirconia.

Despite various mechanical and chemical surface-pretreatment methods, long-term bonding of resin composite to dental zirconia (ZrO2 ) remains a major concern. In this study, graphene oxide (GO) sheets were infused into two commercially available primers and the enclosed mould shear bond strength (EM-SBS) of resin composite to ZrO2 was evaluated. Twelve fully sintered ZrO2 blanks were pretreated and randomly allocated to four groups according to the primers used: RelyX (RX); GO blended RelyX (RXGO); Monobond-S (MB); and GO blended Monobond-S (MBGO). The resin composite stubs were bonded onto the pretreated ZrO2 surfaces and analysed at baseline and after storage in distilled water for 2 and 4 months. The experimental primers blended with GO sheets influenced the surface morphology, visualized as increased surface roughness, and slightly increased the water contact angle measurements. Moreover, the infusion of primers with GO increased the mass fraction (wt%) of carbon and oxygen. The highest EM-SBS values were found for RXGO, with mean (SD) EM-SBS values of 26.4 (3.7) MPa and 21.5 (5.1) MPa after 2 and 4 months of storage, respectively. Infusion of silane primers with nanometre- to micrometre-size GO sheets enhanced the SBS between resin composite and ZrO2 .

Evaluation of the Dentinal Shear Bond Strength and Resin Interface in Primary Molars after Pre-Treatment with Various Dentin Bio-Modifiers: An In Vitro Study.

Dentine adhesives have demonstrated great success with permanent teeth. Though the results in primary teeth are not well documented, some studies have demonstrated lower values of bond strength in primary teeth than those found in permanent teeth. The aim of this study was to compare and evaluate the effect of grape seed extract (6.5%) (Herbal Bio Solutions, Delhi, India), glutaraldehyde (5%) (Loba Chemie PVT. LTD., Mumbai), hesperidin (0.5%) (Herbal Bio Solutions, Delhi, India), and casein phosphopeptide-amorphous calcium phosphate (tooth mousse) (GC Corporation, Alsip, IL, USA) on the shear bond strength of dentine of primary teeth and to evaluate the resin tags at the resin tooth interface. Seventy-five caries-free human primary molars were collected, and their occlusal surfaces were ground flat. Dentin surfaces were etched using phosphoric acid. Then teeth were randomly assigned in sequential order to five groups according to the dentinal treatment method: Group I (Control group) (no treatment), Group II (5% glutaraldehyde), Group III (6.5% grape seed extract), Group IV (0.5% hesperidin), and Group V (CPP-ACP). Ten teeth from each group were assigned for Shear Bond Strength and five for SEM analysis. ANOVA and a post hoc least significant difference test (p < 0.05) were used for statistical analysis of the collected data. The grape seed extract group showed significantly increased shear bond strength than the control group (p < 0.05), and the mean length of resin tags in different dentine bio modifiers groups was also statistically significant (p < 0.05). The use of dentin bio modifiers such as 5% glutaraldehyde, 6.5% grape seed extract, 0.5% hesperidin, and CPP-ACP in the bonding process for primary teeth did not improve the dentinal bond strength.

Using Functionalized Micron-Sized Glass Fibres for the Synergistic Effect of Glass Ionomer on Luting Material.

This laboratory experiment was conducted with the objective of augmenting the mechanical properties of glass ionomer cement (GIC) via altering the composition of GIC luting powder through the introduction of micron-sized silanized glass fibres (GFs). Experimental GICs were prepared through the addition of two concentrations of GFs (0.5% and 1.0% by weight) to the powder of commercially available GIC luting materials. The effect of GF in set GIC was internally evaluated using micro-CT while the mechanical attributes such as nano hardness (nH), elastic modulus (EM), compressive strength (CS), and diametral tensile strength (DTS) were gauged. Additionally, the physical properties such as water solubility and sorption, contact angle (CA), and film thickness were evaluated. Reinforced Ketac Cem Radiopaque (KCR) GIC with 0.5 wt.% GF achieved improved nH, EM, CS, and DTS without affecting the film thickness, CA or internal porosity of the set GIC cement. In contrast, both GF-GIC formulations of Medicem (MC) GIC showed the detrimental effect of the GF incorporation. Reinforcing KCR GIC with 0.5 wt.% silanized GFs could improve the physical and mechanical attributes of luting material. Silanized GF, with optimal concentration within the GIC powder, can be used as a functional additive in KCR GIC with promising results.

Disinfection Efficacy of Laser Activation on Different Forms and Concentrations of Sodium Hypochlorite Root Canal Irrigant against Enterococcus faecalis in Primary Teeth.

Photoactivated disinfection with sodium hypochlorite (NaOCl) has improved primary root canal treatment outcomes. This in vitro study aims to assess and compare the disinfecting efficacy of 2.5% sodium hypochlorite solution and 5.25% sodium hypochlorite gel, without laser activation and accompanied by laser activation, on Enterococcus faecalis-contaminated primary teeth root canals. After one month of incubating extracted teeth specimens with E. faecalis, 36 specimens were randomly divided into two groups: Group A (conventional method without laser-activated irrigation) and Group B (with laser-activated irrigation). Each group was further divided into three subgroups, with six samples in each subgroup. Subgroup 1 received irrigation with normal saline, Subgroup 2 with 2.5% sodium hypochlorite solution, and Subgroup 3 with 5.25% sodium hypochlorite gel. Diode laser activation at 810 nm was used in Group B. Bacterial colony counts were measured before and after the intervention. Student's t-test and one-way analysis of variance (ANOVA) with Tukey's post hoc test were used for statistical analysis. The significance level was set at p < 0.05. Microbial analysis revealed no bacterial growth in samples irrigated with 5.25% sodium hypochlorite gel activated with the laser. Activation with the laser significantly (p = 0.02) improved the disinfection ability of the irrigant compared to the non-activation group. The disinfection ability of sodium hypochlorite gel was better than that of saline (p = 0.02); however, it was comparable to that of sodium hypochlorite solution (p = 0.67). Conclusion: Root canal irrigation with 5.25% sodium hypochlorite gel activated with an 810 nm diode laser resulted in complete eradication of Enterococcus faecalis, indicating its effectiveness as an endodontic disinfection treatment modality.

Efficacy of antimicrobial photodynamic therapy versus antiviral therapy in the treatment of herpetic gingivostomatitis among children: Aa randomized controlled clinical trial.

AIM: The aim of the present study was to evaluate the effect of antimicrobial photodynamic therapy (aPDT) as an adjunctive treatment to topical antiviral therapy for the treatment of children having herpetic gingivostomatitis. MATERIALS AND METHODS: 45 individuals (age group 12-18 years) with herpetic gingivostomatitis (HG) were divided into three groups on the basis of provision of treatment. (a) Group A: topical anti-viral therapy (TAT) (n = 14, mean age = 17.0 years) (b) Group B: antimicrobial photodynamic therapy (aPDT) (n = 15, mean age =17.7 years) and (c) Group C: topical anti-viral therapy + adjunctive aPDT (n = 16, mean age = 18.0 years) respectively. Pain scores [visual analogue scale (VAS) and McGill Pain Questionnaire (MPQ)] were assessed and HSV-1 was quantified. ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA) was used to compute the pro-inflammatory cytokine including interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α). The analysis of the mean values and inter group comparisons were evaluated with the Mann-Whitney test. The Friedman test was used to establish the comparison of the changes observed in HSV quantification, pain scores, and pro-inflammatory cytokines. ANOVA tests were employed for the quantification of differences observed at follow-ups. The assessments for the clinical trial were done at baseline, immediate after post-op, two, and four weeks, and three and six months respectively. RESULTS: According to the analysis of the data obtained after the clinical assessment, the three groups reported a decrease in the pain scores, HSV-1 quantification and levels of the pro-inflammatory cytokines. However, Group C (TAT + aPDT) reported improvement in the observed parameters which was statistically significant in comparison to Group A (TAT) and Group B (aPDT) respectively. CONCLUSION: Antimicrobial photodynamic therapy (aPDT) in conjunction with topical antiviral therapy (TAT) helped in reducing the pain scores and pro-inflammatory cytokine levels in herpetic gingivostomatitis among children.

Team-Based Learning in Prosthodontics Courses: Students' Satisfaction.

The goal of this cross-sectional observational study was to assess dental students' satisfaction regarding team-based learning (TBL) methodology in prosthodontics courses taught at College of Dentistry, Princess Nourah bint Abdulrahman University, Saudi Arabia. Undergraduate dental students at second, third, fourth, and fifth years were taught prosthodontics courses through traditional and TBL pedagogies. TBL sessions consisted of preparation, readiness assurance, and application. At the end of each prosthodontics course, the students were asked to complete a self-administered questionnaire that was divided into four sections to assess the effect of TBL on the following parameters: information acquisition, interpersonal skills improvement, classroom environment, and the students-instructors interaction. The responses of the questionnaire followed the Likert scoring method (scaled from 1 to 5). The t-test and ANOVA statistical analyses were performed using SPSS. Results. The response rate to the questionnaire was 86%. There were a significant relationship and correlation between TBL pedagogy and student satisfaction (P values ≤ 0.05) for all levels. The means of the responses for the second and fifth years were 4.36 and 4.56, respectively, where the means for the third and fourth years were 3.54 and 3.59, respectively. The parameter notably affected by TBL was interpersonal skills enhancement. All students strongly agreed that TBL enhances personal flexibility and boosts their self-esteem. Conclusion. Students showed positive perceptions about TBL pedagogy in terms of active engagement, knowledge acquisition, and improvement of interpersonal skills leading to more efficient learning outcome.

Familiarity and implementation of academicians of dental schools regarding the application of photodynamic therapy in dentistry: A need to incorporate in the dental curriculum.

BACKGROUND: The present cross-sectional study aimed to evaluate the knowledge, behavior, and attitudes of academicians from dental schools in Riyadh, Saudi Arabia towards the use of photodynamic therapy (PDT) in dentistry. METHODS: A self-administered questionnaire to a total of 289 academicians from the dental training faculty (DTF) was distributed to six dental schools in Riyadh, Saudi Arabia during 3 months of the study period. The questionnaire consisted of four main sections with 17 items that dealt with: demographic data, awareness, and knowledge of dental academician regarding PDT technique, and the interest of the dental academician in implementation the PDT technique, detailed knowledge, and background about PDT use followed by the role and integration of PDT technique and its theoretical knowledge in the curriculum and clinical practice. Quantitative data were analyzed using frequency distribution. To estimate if general demographics of the participants affect DTF responses regarding PDT knowledge and teaching experience multivariate statistical analyses were carried out according to gender, age, professional experience, and academic rank regarding selected questions. RESULTS: A total of 238 questionnaires (response rate: 82.3 %) were returned for the analysis. Females responded higher than males. More than 50 % of respondents were age 50 years and less. It is shown that 63 % of DTF indicates familiarization regarding PDT and 67 % and 70 % strongly agree to the fact that PDT should be incorporated in the dental curriculum and important to acquire knowledge regarding PDT for teaching undergraduate. A remarkable number of 87 % and 74 % showed high interest in participating in lectures and workshops related to PDT and therefore clinically applying the technique in clinical practice, respectively. Multivariate analysis showed a statistically significant difference between the level of knowledge and correct answers with age, professional experience of teaching and academic rank. CONCLUSION: Although the DTF involved in the present study demonstrated average knowledge regarding PDT, they, however, consider significantly important and showed a keen interest in acquiring PDT knowledge and adding it in the dental curriculum.

Antimicrobial Capacity and Surface Alterations Using Photodynamic Therapy and Light Activated Disinfection on Polymer-Infiltrated Ceramic Material Contaminated with Periodontal Bacteria.

This study determined the antimicrobial efficiency of light-activated disinfection (LAD) and photodynamic therapy (PDT) on polymer-infiltrated ceramic network (PICN) material contaminated with three periodontal bacteria and explored if PDT and LAD cause PICN surface alterations. Sixty PICN discs were contaminated with Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola and randomly divided into five groups (n = 12 samples/each) according to the treatment groups: Group PDT-PDT (630 ± 10 nm diode laser) with methylene blue; Group DL-808 nm diode laser in contact mode without photosensitizer; Group MB-methylene blue without light application; Group CHX-0.12% chlorhexidine digluconate solution and; Group NT-no treatment. Each disc was then placed in tubes containing phosphate buffered saline (PBS) and vortexed for 30 s to remove the remaining bacteria from the discs. A total of 10× serial dilutions were performed followed by plating of 30 µL of suspension on Brucella agar plates. The colony forming units (CFU) were calculated after 72 h. PICN discs with the attached biofilms were used for confocal microscopy investigation for live/dead bacterial viability. A random single sample from each group was selected to study the bacterial adherence and topographical alterations on PICN discs under scanning electron microscope (SEM). The PDT group showed higher reduction for each bacterial species and total counts of bacteria assessed followed by the DL group (p < 0.05). When compared with MB group, the two laser groups were significantly superior (p < 0.05). The MB group did not show significant differences for any bacteria when compared to NT. The bacteria with the CHX group and DL groups appeared dead with few areas of surviving green stained bacteria. The PDT group showed the highest dead cell count (p < 0.05). PDT and DL groups indicate no significant changes on the surface compared to the sterile PICN discs on visual assessment. Photodynamic therapy produced superior periodontal bacteria reduction over the surface of PICN surface. PDT group showed higher reduction for each bacterial species and total counts of bacteria assessed followed by the DL group. Both PDT and DL treatment strategies are effective without producing surface alterations on PICN.

Characterization of osteogenic cells grown over modified graphene-oxide-biostable polymers.

Graphene is an excellent filler for the development of reinforced composites. This study evaluated bone cement composites of graphene oxide (GO) and poly(methyl methacrylate) (PMMA) based on the proliferation of human bone marrow mesenchymal stem cells (hBMSCs), and the anabolic and catabolic effects of the incorporation of GO on osteoblast cells at a genetic level. Surface wettability and roughness were also evaluated at different GO concentrations (GO1: 0.024 wt% and GO2: 0.048 wt%) in the polymer matrix. Fabricated specimens were tested to (a) observe cell proliferation and (b) identify the effectiveness of GO on the expression of bone morphogenic proteins. Early osteogenesis was observed based on the activity of alkaline phosphatase and the genetic expression of the run-related transcription factor 2. Moreover, bone strengthening was determined by examining the collagen type 1 alpha-1 gene. The surface roughness of the substrate material increased following the addition of GO fillers to the resin matrix. It was found that over a period of ten days, the proliferation of hBMSCs on GO2 was significantly higher compared to the control and GO1. Additionally, quantitative colorimetric mineralization of the extracellular matrix revealed greater calcium phosphate deposition by osteoblasts in GO2. Furthermore, alizarin red staining analysis at day 14 identified the presence of mineralization in the form of dark pigmentation in the central region of GO2. The modified GO-PMMA composite seems to be promising as a bone cement type for the enhancement of the biological activity of bone tissue.

Synthesis and characterization of wollastonite glass-ceramics for dental implant applications.

OBJECTIVES: To synthesize a glass-ceramic (GC) that is suitable for non-metallic one-piece dental implant application. METHODS: Three glasses in a SiO2-Al2O3-CaO-CaF2-K2O-B2O3-P2O5-CeO2-Y2O3 system were produced by wet chemistry. Differential thermal analysis (DTA) was carried out to determine the glass crystallization kinetic parameters and the heating schedules that were used for sintering of GCs. Crystalline phases and crystal morphologies were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Mechanical properties of the GCs were determined by ultrasonic and indentation tests and its machinability were evaluated. Chemical durability was carried out according to ISO 6872, whereas testing chemical degradation in tris buffered solution was executed according to ISO 10993-14. RESULTS: XRD of the GC specimens showed that wollastonite was the main crystalline with other secondary phases; GC2 had cristobalite as an additional phase. SEM of the GCs revealed dense acicular interlocking crystals. Young's modulus of elasticity (E), true hardness (Ho) and fracture toughness (KIC) of the GCs were 89-100GPa, 4.85-5.17GPa and 4.62-5.58MPam(0.5), respectively. All GCs were demonstrated excellent machinability. The GCs exhibited various chemical durability and degradation rates. KIC values of the GCs following chemical durability testing were not significantly different from those of the original materials (p>0.05). GC2 exhibited significantly higher KIC value compared with GC1 and GC3 (p<0.05) and its chemical durability satisfied ISO 6872 specification for dental ceramics. SIGNIFICANCE: Wollastonite-cristobalite GC can be considered as a promising material for one-piece dental implant applications due to its strength, machinability and chemical durability.

Synthesis of bioactive and machinable miserite glass-ceramics for dental implant applications.

OBJECTIVES: To synthesize and characterize machinable, bioactive glass-ceramics (GCs) suitable for dental implant applications. METHODS: A glass in the SiO2-Al2O3-CaO-CaF2-K2O-B2O3-La2O3 system was synthesized by wet chemical methods, followed by calcination, melting and quenching. Crystallization kinetics were determined by differential thermal analysis (DTA). GC discs were produced by cold pressing of the glass powder and sintered using schedules determined by DTA. The crystalline phases and microstructure of GC samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Dynamic Young's modulus (E), true hardness (Ho), fracture toughness (KIC) and brittleness index (BI) were evaluated. Bioactivity was studied by examining the formation of hydroxyapatite (HA) on the GC surfaces after soaking in simulated body fluid (SBF). Attachment and proliferation of MC3T3-E1 osteoblastic cells were assessed in vitro. RESULTS: Miserite [KCa5(Si2O7)(Si6O15)(OH)F] was the main crystalline phase of the GC with additional secondary phases. Microstructural studies revealed interlocking lath-like crystalline morphology. E, Ho, and KIC values for the GCs were 96±3 GPa, 5.27±0.26 GPa and 4.77±0.27 MPa m(0.5), respectively. The BI was found to be 1.11±0.05 µm(-0.5), indicating outstanding machinability. An HA surface layer was formed on the GC surfaces when soaked in SBF, indicating potential bioactivity. MC3T3-E1 cells exhibited attachment, spreading and proliferation on GC surfaces, demonstrating excellent biocompatibility. SIGNIFICANCE: We present a novel approach for the synthesis of miserite GC with the physical and biological properties required for non-metallic dental implant applications.