Proteolytic activity and degradation of bovine versus human dentin matrices.

OBJECTIVE: Non-human teeth have been commonly used in research as replacements for human teeth, and potential dissimilarities between the dental tissues should be considered when interpreting the outcomes. To compare the proteolytic activity and degradation rate of bovine and human dentin matrices. METHODOLOGY: Dentin beam specimens were obtained from human molars (n=30) and bovine incisors (n=30). The beams were weighed hydrated and after complete dehydration to obtain the mineralized wet and dry masses. Then, the beams were demineralized in 10 wt% phosphoric acid. Next, 15 beams from each substrate were randomly selected and again dehydrated and weighed to obtain the initial demineralized dry mass (DM). Then, the beams were stored in saliva-like buffer solution (SLBS) for 7, 14 and 21 days. SLBS was used to evaluate hydroxyproline (HYP) release after each storage period. The remaining beams of each substrate (n=15) were tested for initial MMP activity using a colorimetric assay and then also stored in SLBS. DM and MMP activity were reassessed after 7, 14 and 21 days of incubation. The data were subjected to two-way ANOVA tests with repeated measures complemented by Bonferroni's tests. Unpaired two-tailed t-tests were also used (p<0.05). RESULTS: Similar water and inorganic fractions were found in human and bovine dentin, while human dentin had a higher protein content. The most intense proteolytic activity and matrix deterioration occurred short after dentin was demineralized. Both substrates exhibited a sharp reduction in MMP activity after seven days of incubation. Although human dentin had higher MMP activity levels, greater HYP release and DM loss after seven days than bovine dentin, after 14 and 21 days, the outcomes were not statistically different. CONCLUSION: Bovine dentin is a suitable substrate for long-term studies involving the degradation of dentin matrices.

Assessment of Passiflora incarnata L for conscious sedation of patients during the extraction of mandibular third molars: a randomized, split-mouth, double-blind, crossover study.

OBJECTIVE: The aim of the present study was to evaluate the efficacy of Passiflora incarnata L for the control of anxiety during third mandibular molar extraction and compare it to midazolam, the most used benzodiazepine in dentistry. METHOD AND MATERIALS: The investigators implemented a prospective, randomized, double-blind, split-mouth study. The degree of anxiety of the patients was assessed before the surgical procedure. The surgeries took place in two sessions: one on each side of the hemi-mandible and, on each of them, the patient received one of the drugs, crosswise. Anxiety control was measured through physical parameters, at the following periods during the surgery: (1) immediately administration of anxiolytic medication, (2) 30 minutes after anxiolytic medication, (3) after extraoral antisepsis, (4) after local anesthesia, (5) during incision, (6) during osteotomy, (7) between osteotomy and odontosection, (8) during odontosection, (9) during surgical store curettage, (10) during suture, and (11) immediately after postoperative care guidelines. Lastly, the volunteers received a self-assessment form in order to report their experience. Statistical analysis was performed using the Wilcoxon test. RESULTS: The final sample was composed of 20 patients, with a mean age of 22.5 years. The results of the physical parameters showed statistically significant differences (P < .05) for certain times and physical parameters, especially heart rate (P = .036), which showed the highest control for Passiflora at time point (3). The undesirable effects reported by patients such as drowsiness, muscle relaxation, and dizziness were greater with benzodiazepine. CONCLUSION: The results of this study suggest that Passiflora may be considered as an alternative to midazolam in controlling anxiety in dentistry. Future studies will focus on other benzodiazepines and herbal medicines.

Proteolytic activity and degradation of bovine versus human dentin matrices

Abstract Non-human teeth have been commonly used in research as replacements for human teeth, and potential dissimilarities between the dental tissues should be considered when interpreting the outcomes. Objective: To compare the proteolytic activity and degradation rate of bovine and human dentin matrices. Methodology: Dentin beam specimens were obtained from human molars (n=30) and bovine incisors (n=30). The beams were weighed hydrated and after complete dehydration to obtain the mineralized wet and dry masses. Then, the beams were demineralized in 10 wt% phosphoric acid. Next, 15 beams from each substrate were randomly selected and again dehydrated and weighed to obtain the initial demineralized dry mass (DM). Then, the beams were stored in saliva-like buffer solution (SLBS) for 7, 14 and 21 days. SLBS was used to evaluate hydroxyproline (HYP) release after each storage period. The remaining beams of each substrate (n=15) were tested for initial MMP activity using a colorimetric assay and then also stored in SLBS. DM and MMP activity were reassessed after 7, 14 and 21 days of incubation. The data were subjected to two-way ANOVA tests with repeated measures complemented by Bonferroni's tests. Unpaired two-tailed t-tests were also used (p<0.05). Results: Similar water and inorganic fractions were found in human and bovine dentin, while human dentin had a higher protein content. The most intense proteolytic activity and matrix deterioration occurred short after dentin was demineralized. Both substrates exhibited a sharp reduction in MMP activity after seven days of incubation. Although human dentin had higher MMP activity levels, greater HYP release and DM loss after seven days than bovine dentin, after 14 and 21 days, the outcomes were not statistically different. Conclusion: Bovine dentin is a suitable substrate for long-term studies involving the degradation of dentin matrices.