A Systematic Review on Maxillofacial Prosthesis with Respect to Their Color Stability.

The aim of this systematic review was to identify and analyze the findings of various studies that analyzed the changes in the color stability of maxillofacial prosthetic materials after the addition of various colorants and nanoparticles and assess the change in color after being subjected to either natural or artificial accelerated aging as well as outdoor aging. This systematic review was conducted in accordance with the guidelines of transparent reporting of systematic reviews and meta-analysis (PRISMA Statement). The primary objective of this systematic review was to evaluate the color stability of maxillofacial prosthesis. The secondary objective was to assess the effect of various colorants; pigments; opacifiers; UV absorbers-such as inorganic colorants (dry earth pigments); metal oxides; and organic colorants. The time period of the included studies extended from 2013 to 2023. Electronic database search identified a total of 217 studies. Ten studies were included to meet the research question. All 10 included studies analyzed the effect of various colorants and their exposure to various aging and weathering conditions. It was found that various pigments and nanoparticles had an effect on the color stability. Also weathering and aging conditions had a direct effect on the color stability as well. In terms of disinfection, although there was not much color difference observed, highest change in color stability was observed when rubbing or brushing of the prosthesis was carried out. In conclusion, the color stability of maxillofacial prosthetics is a critical factor that influences both patient satisfaction and the overall cosmetic look. The potential of pigments and nanoparticles to enhance the color stability of silicone-based maxillofacial prosthesis has received much research. By avoiding color fading and discoloration brought on by environmental variables including UV radiation, aging, and chemical exposure, the inclusion of various pigments and nanoparticles has been demonstrated to improve the color stability of silicone maxillofacial prostheses.

The role of microRNAs on the pathogenesis, diagnosis and management of portal hypertension in patients with chronic liver disease.

INTRODUCTION: Portal hypertension (PH) is the elevated pressure in the portal vein, which results in poor functioning of the liver and is influenced by various factors like liver cirrhosis, nonalcoholic fatty liver disease, schistosomiasis, thrombosis, and angiogenesis. Though the diagnosis and treatment have been advanced, early diagnosis of the disease remains a challenge, and the diagnosis methods are often invasive. Hence, the clear understanding of the molecular mechanisms of PH can give rise to the development of novel biomarkers which can pave way for early diagnosis in noninvasive methods, and also the identification of target genes can elucidate an efficient therapeutic target. AREAS COVERED: PubMed and Embase database was used to search articles with search terms 'Portal Hypertension' or 'pathophysiology' and 'diagnosis' and 'treatment' or "role of miRNAs in portal hypertension. EXPERT OPINION: Interestingly, biomarkers like microRNAs (miRNAs) have been studied for their potential role in various diseases including hypertension. In recent years, miRNAs have been proved to be an efficient biomarker and therapeutic target and few studies have assessed the roles of miRNAs in PH. The present paper highlights the potential roles of miRNAs in PH.

Comparison of Interactive Teaching in Online and Offline Platforms among Dental Undergraduates.

In recent years, the educational system has focused more on the holistic development of an individual. Modern technology has changed the educational environment to provide students with better academic opportunities. Along with the education system, teaching techniques and learning tools have also changed with digital evolution. This research was undertaken to assess the academic performance of interactive teaching methods in offline and online platforms in Periodontics among BDS undergraduates at a dental college in India. This prospective study was conducted among 49 students: Group I (n = 24, online class through Zoom) and Group II (n = 25, offline classes). The subject was divided into three modules and was covered in one week. The topics covered, teaching methods, lectures, and activities were similar for both groups. A formative assessment mark was obtained from written tests during the module, whereas the summative assessment mark was recorded from exams conducted towards the end of the module. In the results, a statistically significant difference was not observed in terms of formative assessment between Group I (77.88 ± 12.89) and Group II (77.80 ± 16.09) (p = 0.98). In addition, a statistically significant difference was not observed in terms of summative assessment between Group I (80.54 ± 8.39) and Group II (80.28 ± 11.57) (p = 0.93). Overall, this study suggests that interactive teaching methods in both offline and online platforms in Periodontics showed equivalent performance by the undergraduate dental students.

Phosphorescent wax - The novel approach of innovation.

The present invention relates to dental compositions that include a phosphorescent material, more particularly, adding phosphorescent material to waxes that used in dentistry. The aim of the study is to develop a wax that has innate phosphorescent properties. Three groups of samples were taken in which the phosphorescent material was added. Three groups were later compared for their phosphorescent property in the material. All the samples in the initial molten state were poured into a mold made of silicone impression material and allowed to set. The material was placed in a dark room, and visual examination was done to compare the materials. From the samples obtained, paraffin wax showed more phosphorescent property than beeswax. The least phosphorescent property was seen in marginal wax. It can be concluded from this study that paraffin wax showed the most phosphorescent property.

Troubleshooting in complete denture fabrication.

In countries with a high amount of geriatric patients, it is mandatory for a dental clinician to have working knowledge on complete denture (CD) procedures. The aim of this study was to troubleshoot the errors in denture fabrication by assessing the difficulties in clinical procedures. A questionnaire was distributed among dental undergraduates across the country in the present study. A total of 26 questions were included in the study. An online sharing medium was used for distribution and a total of 140 responses were received. SPSS for windows, version 20 was used for data tabulation. Descriptive statistics and Chi-square test were done. The results of this study revealed that jaw relation was the most difficult procedure followed by border molding. Multiple problems arise from the practitioner's end due to the lack of knowledge. One of the causes for these problems could be inability to learn the principles and procedures during the undergraduate program. This must be addressed at the base level so that better care can be given to patients.

Wear Resistance, Color Stability and Displacement Resistance of Milled PEEK Crowns Compared to Zirconia Crowns under Stimulated Chewing and High-Performance Aging.

Recently, polyetheretherketone (PEEK) has been introduced to the dental market as a high-performance and chemically inert biomaterial. This study aimed to compare the wear resistance, abrasiveness, color stability, and displacement resistance of zirconia and PEEK milled crowns. An ideal tooth preparation of a first maxillary molar was done and scanned by an intraoral scanner to make a digital model. Then, the prosthetic crown was digitally designed on the CAD software, and the STL file was milled in zirconia (CaroZiir S, Carol Zircolite Pvt. Ltd., Gujarat, India) and PEEK (BioHpp, Bredent GmbH, Senden, Germany) crowns using five-axis CNC milling machines. The wear resistance, color stability, and displacement resistance of the milled monolithic zirconia with unfilled PEEK crowns using a chewing simulator with thermocyclic aging (120,000 cycles) were compared. The antagonist wear, material wear, color stability, and displacement were evaluated and compared among the groups using the Wilcoxon-Mann-Whitney U-test. Zirconia was shown to be three times more abrasive than PEEK (p value < 0.05). Zirconia had twice the wear resistance of PEEK (p value < 0.05). Zirconia was more color stable than PEEK (p value < 0.05). PEEK had more displacement resistance than zirconia (p value < 0.05). PEEK offers minimal abrasion, better stress modulation through plastic deformation, and good color stability, which make it a promising alternative to zirconia crown.

Zebrafish as a potential biomaterial testing platform for bone tissue engineering application: A special note on chitosan based bioactive materials.

Biomaterials function as an essential aspect of tissue engineering and have a profound impact on cell growth and subsequent tissue regeneration. The development of new biomaterials requires a potential platform to understand the host-biomaterial interaction, which is crucial for successful biomaterial implantation. Biomaterials analyzed in rodent models for in vivo research are cost-effective but tedious, and the practice has many technical difficulties. As an alternative, zebrafish provide an excellent biomaterial testing platform over the current rodent models. During growth and recovery, zebrafish bone morphogenesis shows a variety of inductive signals involved in the cycle that are close to those influencing differentiation of bone and cartilage in mammals, including humans. This platform is cheap, optically transparent, quick to change genes, and provides reliable reproducibility on short life cycles. Chitosan is a well-known biomaterial in the field of tissue engineering. In view of its documented use in bone regeneration, the biological characterization of chitosan-based bioactive materials in the zebrafish model has been featured in an outstanding note. We, therefore, outlined this review of the zebrafish as a potential in vivo research model for the rapid characterization of the biological properties of new biomaterials for bone tissue engineering applications.

Evaluation of the sub-acute toxicity of Acacia catechu Willd seed extract in a Wistar albino rat model.

Acacia catechu (A. catechu) or Khair (Hindi) is used in several herbal preparations in the Ayurvedic system of medicine in India. Traditionally, this drug is beneficial against several gastrointestinal and stomach related ailments, and leprosy. The present investigation was carried out to evaluate the sub-acute oral toxicity of the ethanolic extract of A. catechu seeds in Wistar albino rats. Results obtained from the quantitative chemical analysis of A. catechu seed extract were compared with commercially available standards. A. catechu seed extract was administered orally at the doses of 250, 500 and 1000 mg/kg b.w. daily for 28 days. General behavior, bodyweight and mortality were examined during the entire study period. At the end of 28 days, hematological and biochemical parameters along with the relative organ weights were determined. It was observed that the extract did not induce death or any significant changes in the body weight, relative weight of vital organs and in hematological parameters for up to a dose of 1000 mg/kg. The oral administration of the plant extract did not produce any significant changes in the levels of glucose. In addition, there were no significant changes in the activity of both hepatotoxic and nephrotoxic marker enzymes in the serum. Oral administration of A. catechu also did not produce any significant changes in the levels of oxidative markers. Furthermore, the findings from the biochemical studies were, well corroborated with the histological findings.

In vitro evaluation of fracture resistance and cyclic fatigue resistance of computer-aided design-on and hand-layered zirconia crowns following cementation on epoxy dies.

AIM: This in vitro study was to compare the fracture resistance and cyclic fatigue resistance of hand-layered zirconia crowns and computer-aided design (CAD)-on crowns (lithium disilicate with zirconium oxide). SETTINGS AND DESIGN: Comparative -Invitro study design. MATERIALS AND METHODS: All ceramic crown preparation was done on a mandibular molar ivorine tooth, impression made, and duplicated. Twenty hand-layered zirconia crowns and twenty CAD-on crowns were fabricated using CAD/computer-aided manufacturing (CAD/CAM) technique. All crowns were cemented to their respective dies using resin cement for evaluating fracture resistance and cyclic fatigue resistance using universal testing machine. STATISTICAL ANALYSIS USED: Independent samples t-test, Mann-Whitney U-test, and Shapiro-Wilk test were used. RESULTS: The mean fracture resistance of CAD-on crowns (2660.50 ± 501.303 N) was significantly more than that of hand-layered zirconia crowns (1963.60 ± 452.895 N) (independent samples t-test, P < 0.023). Cyclic fatigue resistance test results showed that the mean number of cycles before failure for hand-layered zirconia crowns was 175,297 and for CAD-on crowns was 212,097 (Mann-Whitney U-test, P < 0.012). CONCLUSION: CAD-on crowns were found to have significantly higher fracture resistance and cyclic fatigue resistance properties than hand-layered zirconia crowns.

Blended Module-Based Teaching in Biostatistics and Research Methodology: A Retrospective Study with Postgraduate Dental Students.

Information technology has stimulated efforts to reform teaching methods in dental education. Most of these efforts involve a shift from conventional mode to the more technology-savvy and student-centered approach. The aim of this study was to compare postgraduate dental students' academic performance using two teaching methodologies (video-based learning and blended module-based learning) in a biostatistics and research methodology course in a master's program at a dental college in India. This retrospective study involved two groups of students enrolled in the master's program with different years of admission: Group I in 2013-14 (n=80) and Group II in 2015-16 (n=80). Group I students learned the subjects with video-based learning, whereas Group II students were taught using a blended module program using a small-group learning system called Process-Oriented Guided Inquiry Learning (POGIL). The students' final course evaluation (summative assessment) and formative assessment (during course assessments) were compared for the two groups. The students' final course evaluation was derived from an end-of-year written examination, whereas the formative assessment was recorded with written tests and projects during the course. In the results, the summative assessment did not show a significant difference between Group I (68.2±13.4) and Group II (66.4±11.9) (p=0.39). The formative assessment showed a significant difference (p<0.001) in favor of the Group II students. In this study, the blended module-based teaching produced similar scores on the final exam to the video-based lectures, but it produced significantly better results on the in-course assessments. The latter finding could be attributed to the incorporation of small-group learning and POGIL.

Impact of Video Based Learning on the Perfomance of Post Graduate Students in Biostatistics: A Retrospective Study.

INTRODUCTION: Education, being a process of knowledge transfer always has advances which are generally on par with the discovery of newer technologies. Currently, most of the education process has shifted away from the conventional black board towards the usage of more student friendly technologies. This leads us to the aim of this study, which is to analyse the impact of video based learning on the performance of dental post graduate students in their biostatistics course. MATERIALS AND METHODS: A new video based discussion method was followed to teach biostatistics to MDS postgraduate students in 2013 (test group, n=44). The performance of these students were compared to a historical cohort of scores obtained by students of the 2012 batch (control group, n=44) who underwent a traditional lecture based teaching for the same course. The scores obtained by the students in their undergraduate board exams were compared to test for difference in academic aptitude of the students in the two groups. RESULTS: The mean exam score of the test group was significantly higher (66.60±8.92) when compared to the control group (53.48±8.38); (p < 0.001 Independent Sample t-test). There was no significant difference in the overall academic performance of the students from both groups (test group mean academic performance was 61.47±4.86 and control group was 63.19±4.69. CONCLUSION: The results of this study suggest that video based discussion based teaching is more effective in training postgraduate dental students in biostatistics.

Critical appraisal-based learning in a dental college in India: a randomized control study.

This study examined the effect of critical appraisal exercises on the quality of preclinical tooth preparation skills and the confidence level of undergraduate dental students at a dental college in India. Forty-two student volunteers were randomly divided into critical appraisal (CA; n=19) and control (C; n=23) groups. Both groups were given conventional lecture and video demonstration; the CA group was also given critical appraisal exercises. Four evaluators assessed the incisor, canine, premolar, and molar preparations made by all students. The mean overall scores (reported as mean±SD) assigned to the CA group by all evaluators were significantly higher (independent t-test, p<0.05) than the C group for incisor (CA: 6.19±1.47, C: 5.09±1.52), canine (CA: 5.64±1.36, C: 4.50±1.35), premolar (CA: 5.88±1.03, C: 4.88±1.18), and molar (CA: 5.98±1.16, C: 5.20±0.71) teeth. The CA group also demonstrated a significant increase in self-confidence over that of the C group (repeated measures general linear model F=8.554, p=0.006). In this study, the critical appraisal exercises significantly improved the preclinical incisor, canine, premolar, and molar tooth preparation skills and the confidence level of the undergraduate dental students.

Dental fusion: a case report of esthetic conservative management.

The management techniques reported for dental fusion are usually complex, invasive, and irreversible. This case report describes a novel, simple technique to manage double teeth using resin restorations. The promising results obtained will encourage dental practitioners to consider this conservative approach before more complex treatment alternatives.