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Introduction: In stomatology, the evaluation of bite power is crucial. It is considered a significant objective approach to evaluating masticatory performance. Bite force has become a significant outcome analysis index for various therapies in dentistry research. Presently several devices being used globally have their graces and faults. They are costly and also not available easily to the general dental practitioner. Objectives: Development of a novel indigenous instrument for the measurement of human bite force. Methods: This paper describes an indigenously developed and researched instrument to measure human bite force. The sensor data (change in electronic resistance under applied force) will be read by the microprocessor and converted to force values in newton. The bite force result will be instantly displayed on the screen of the instrument and the device with which it is connected. Results: The developed instrument is handy and user-friendly and can measure bite force accurately and repeatedly. Conclusions: In this research paper, an economical, lightweight, user-friendly, accurate, and reproducible human bite force measurement device is explained, which has been developed indigenously.
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Background It is essential for dentists and technicians to work together to fabricate and create restorations that are a "perfect" shade match for a particular person. Thus, the Vitapan 3D-Master tooth shade system (Vita Zahnfabrik, Germany) was created and put into use in order to improve the accuracy of shade-selection operations. The objective was to visually assess the color of the maxillary anterior teeth in male and female subjects from various age groups in Uttar Pradesh, India. Materials and methods There were 150 patients in total, and they were divided equally into three groups of 50: Group I, which included patients aged 18 to 30; Group II, which included patients aged 31 to 40; and Group III, which included patients aged 41 to 50. Ceiling-mounted fluorescent lighting fixtures with PHILIPS 65 D tubes (OSRAM GmbH, Germany) were installed. Three medical experts provided their opinions as part of this research. The maxillary central incisor was placed next to tabs of various shades, and the doctors' final assessment was based solely on the central one-third of the face. From each of the two sample sets, a total of 30 patients were selected. Once the crown had been made from the prepared tooth of the patient, it was colored according to two shade guidelines (Vita Classic and Vita 3D Master). The three clinicians matched the shade of the manufactured crown with visual shade guides. For shade matching, a modified United States Public Health Service (USPHS) standard was employed. Results The Chi-square test was used to compare categorical variables across groups. According to the Vitapan Classic shade guide, 26% of Group I participants matched the first Hue group (A1), 14% of Group II participants matched the first Hue group (A3), and 20% of Group III participants matched the second Hue group (B2). Master shade guide for Vita 3D 26% of Group I participants matched with the second value group (2M2), 18% of Group II participants matched with the third value group (3L 1.5), and 24.5% of Group III participants matched with the third value group (3M2). Eighty percent of people who were matched to Alpha scored for crowns made using the Vita 3D Master shade guide, while 94.1% of people who were matched to Charlie scored for crowns made using the Vitapan Classic shade guide in a comparison of the two shade guides. Conclusion The majority of the shades obtained from the Vita 3D master shade guide were found to be 1M1 and 2M1 in the younger patients, 2M1 and 2M2 in the second age group, and 3L 1.5, 3M2 in the older age group. In contrast, the Vitapan Classic shade guide revealed A1, A2, A3, B2, C1, D2, and D3 as the predominant shades.
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We investigate the differential effects of a new index of Twitter-based market uncertainty (TMU) and variables for the US equity market before and during the Covid-19 pandemic. We find that markets are significantly more sensitive to the uncertainty contained in tweets during the pandemic, the TMU is a leading indicator of returns only during the pandemic, and the effect of the TMU on the volatility and liquidity of equity markets is greater during the pandemic compared to the pre-pandemic period. Our results show that the information contained tweets are having a much larger effect on equity markets during the pandemic.
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PURPOSE: Acrylic denture base tends to fracture frequently during their service due to poor strength. The surface roughness of denture base is a critical property because denture base with rough surface will cause accumulation of food particles ,thereby leading plaque retention . Microbes such as candida albicans are seen inhabitating the surface. MATERIALS AND METHODS: Conventional heat cure denture base reins(DPI) and heat cure denture base resin with incorporation of 15wt% aluminium oxide was studied in two groups with 20 samples each. A mold of size 65 mm × 10 mm × 3 mm (ISO Standard) was obtained by investing brass rectangles. About forty specimens were prepared. Specimens were divided into two groups (n = 20) coded A and B. Group A was the control group (n = 20) without addition of aluminum oxide. Group B was the experimental group (n = 20) with addition of 15 wt % aluminum oxide. All the specimens were stored in distilled water for 14 days. The flexural strength was measured using a three-point bending test in a universal testing machine, and the surface roughness was measured using contact-type profilometer. RESULTS: Incorporation of 15wt% aluminum oxide leads to a significant increase in flexural strength and surface roughness of conventional heat-cure denture base resin.
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AIM: The aim of the study is to investigate the effect of joint surface preparations and chemical surface treatment given to prepared surface on the transverse strength of repaired denture base resin. METHODOLOGY: Two hundred and twenty specimens (DPI India) were randomly allocated into eight groups (n = 10), according to the combination of joint surface preparation (Butt joint, 45° bevel, and rounded joint) and chemical surface treatment (methylene chloride, ethyl acetate, and methyl methacrylate) for 30 and 60 s each. Specimens, after surface treatment, were repaired with self-cured resin (DPI India) and then subjected to 3-point bending test to measure transverse strength. Fractured surfaces were viewed under stereomicroscope and subjected to AutoCAD analysis to determine type of failure (adhesive or cohesive) and measure their area. Measurement data were analyzed by one-way analysis of variance, paired t-test, Dunnett's D test, and multiple comparison Bonferroni t-test, with a 5% significance level. RESULTS: Most of the comparisons between the test specimens were statistically significant. Specimens (methylene chloride for 60 s and rounded joint) show 60%-70% gain of strength. CONCLUSIONS: For providing better bond strength to a repaired specimen, the segment of fractured specimens to be provided "Rounded joint" preparation with etching by methylene chloride for 60 s.
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OBJECTIVES: The present study is conducted to explore the knowledge, attitude, and practice towards impression technique and materials for recording impression in implant placement among general dental practitioners. MATERIALS AND METHODS: The present study is a cross-sectional questionnaire study. The study was conducted among general dental practitioners in Patna city in November-December 2017. Patna city was divided into five directions, which are north, south, east, west, and central. From each direction, 20 clinics were selected randomly, and dental practitioners from there clinics were interviewed. A closed-ended questionnaire consists of 19 items was prepared, the questionnaire was divided into four parts. RESULTS: Majority of study participants (58 [34%]) were above the age of 40 years. 96 (56%) of study participants were male. Most of the study participants (89 [50%]) were having MDS degree. Knowledge, attitude, and behavior scores among study participants. About 43% of study participants have good knowledge scores regarding impression technique and material in implant placement while 50% of study participants had fair attitude score. About 58% of study participants had fair practice score. There was statistically significant correlation (P ≤ 0.05*) between knowledge and attitude of study participants. CONCLUSION: It was concluded that there was good knowledge, fair attitude, and practice among the dental professionals regarding the impression technique and materials for recording impression in implant placement. There was statistically significant correlation between knowledge and attitude of study participants. There was statistically significant correlation between some demographic variables and knowledge, attitude, and practice of study participants.