No abstract

The purpose of this study was to investigate a group of Brazilian dental students' knowledge about HIV infection, the infection control measures utilized by the dental students, and students' attitudes towards treating HIV/AIDS patients. The study population consisted of 250 dental students from Universidade Federal da Bahia, Brazil, who were treating patients in clinics of the university and extra-mural rotations at the time of the study. The survey instrument was a self-administered questionnaire which consisted of 32 pre-coded questions and two open-ended questions. The overall response rate to the questionnaire was 54%. More than 80% of respondents (N = 135) considered every dental patient a potential HIV carrier. A majority of the students were aware of the association between HIV and Kaposi's sarcoma (92.5%), oral candidiasis (90.3%) and oral hairy leukoplakia (52.7%). A gender difference was observed in students' knowledge of oral manifestations and infection control measures, with females having better knowledge than males (p < 0.05). Because of certain inadequacies in knowledge and infection control practices among respondents, a curriculum focusing on the management of HIV/AIDS, including infection control and legal issues is recommended.

Objectives Test the hypotheses that there are equivalent wear rates for enamel-versus-enamel and ceramic-versus-enamel, analyzing the in vivo wear of crown ceramics, their natural enamel antagonists, and the corresponding two contralateral teeth; and, that bite force does not correlate with the wear. Methods A controlled, clinical trial was conducted involving patients needing full coverage crowns opposing enamel antagonists. Bite forces were measured using a bilateral gnathodynamometer. Single-unit restorations of metal/ceramic (Argedent 62, Argen Corp/IPS d.SIGN veneer); or, core-ceramic/veneer from either, Empress2/Eris, or e.maxPress core/e.maxCeram glaze (ceramics: Ivoclar Vivadent, USA) were randomly assigned, fabricated and cemented. Impressions were made of the ceramic crowns, as well as each maxillary and mandibular quadrant at one week (baseline) and one, two and three years. Resulting models were scanned (3D laser scanner). Maximum wear was calculated by superimposing baseline with annual images. Results There were a total of thirty-six crowns required for thirty-one patients. Each restoration had three associated enamel teeth; 1) crown, 2) antagonist, 3) contralateral, and 4) contralateral-antagonist. SAS PROC MIXED (α=0.05) indicated no statistical significance for mean maximum wear among crown ceramics, enamel antagonists and contralaterals. However, enamel wear was statistically significant in relation to intraoral location (p=0.04) and among years (p<0.02). Analyzed alone, the enamel contralateral-antagonist exhibited significantly greater wear (p<0.001). Considering all wear sites, there was no correlation with bite force (p=0.15). Significance The ceramics and their antagonists exhibited in vivo wear rates within the range of normal enamel. Future studies should examine the wear implications of the contralateral-antagonist enamel.

Purpose Analyzing the clinical performance of restorative materials is important, as there is an expectation that these materials and procedures will restore teeth and do no harm. The objective of this research study was to characterize the clinical performance of metal-ceramic crowns, core ceramic crowns, and core ceramic/veneer ceramic crowns based on 11 clinical criteria. Materials and Methods An IRB-approved, randomized, controlled clinical trial was conducted as a single-blind pilot study. The following three types of full crowns were fabricated: (1) metal-ceramic crown (MC) made from a Pd-Au-Ag-Sn-In alloy (Argedent 62) and a glass-ceramic veneer (IPS d.SIGN veneer); (2) non-veneered (glazed) lithium disilicate glass-ceramic crown (LDC) (IPS e.max Press core and e.max Ceram Glaze); and (3) veneered lithia disilicate glass-ceramic crown (LDC/V) with glass-ceramic veneer (IPS Empress 2 core and IPS Eris). Single-unit crowns were randomly assigned. Patients were recalled for each of 3 years and were evaluated by two calibrated clinicians. Thirty-six crowns were placed in 31 patients. A total of 12 crowns of each of the three crown types were studied. Eleven criteria were evaluated: tissue health, marginal integrity, secondary caries, proximal contact, anatomic contour, occlusion, surface texture, cracks/chips (fractures), color match, tooth sensitivity, and wear (of crowns and opposing enamel). Numerical rankings ranged from 1 to 4, with 4 being excellent, and 1 indicating a need for immediate replacement. Statistical analysis of the numerical rankings was performed using a Fisher’s exact test. Results There was no statistically significant difference between performance of the core ceramic crowns and the two veneered crowns at year 1 and year 2 (p > 0.05). All crowns were rated either as excellent or good for each of the clinical criteria; however, between years 2 and 3, gradual roughening of the occlusal surface occurred in some of the ceramic-ceramic crowns, possibly caused by dissolution and wear of the glaze. Statistically significant differences in surface texture (p = 0.0013) and crown wear (p = 0.0078) were found at year 3 between the metal-ceramic crowns and the lithium-disilicate-based crowns. Conclusion Based on the 11 criteria, the clinical performance of ceramic-ceramic crowns was comparable to that of the metal-ceramic crowns after 2 years; however, gradual roughening occurred between years 2 and 3, which resulted in differences in surface texture and wear.

The purpose of this study was to investigate a group of Brazilian dental students' knowledge about HIV infection, the infection control measures utilized by the dental students, and students' attitudes towards treating HIV/AIDS patients. The study population consisted of 250 dental students from Universidade Federal da Bahia, Brazil, who were treating patients in clinics of the university and extra-mural rotations at the time of the study. The survey instrument was a self-administered questionnaire which consisted of 32 pre-coded questions and two open-ended questions. The overall response rate to the questionnaire was 54%. More than 80% of respondents (N = 135) considered every dental patient a potential HIV carrier. A majority of the students were aware of the association between HIV and Kaposi's sarcoma (92.5%), oral candidiasis (90.3%) and oral hairy leukoplakia (52.7%). A gender difference was observed in students' knowledge of oral manifestations and infection control measures, with females having better knowledge than males (p < 0.05). Because of certain inadequacies in knowledge and infection control practices among respondents, a curriculum focusing on the management of HIV/AIDS, including infection control and legal issues is recommended.