Biomedical subjects

Kamran Safavi

Publications and source records attributed to Kamran Safavi.

3 recordsLinked to original sources

PubMed2004

Chlorhexidine substantivity in root canal dentin.

OBJECTIVE: The purpose of this investigation was to evaluate the substantivity of chlorhexidine (CHX) within a root canal system and to assess how long the CHX remains antimicrobially effective. STUDY DESIGN: Bovine roots were sectioned and standardized to 8 mm. Sections, which served as controls, were treated with 1% sodium hypochlorite and 1 mol/L EDTA, then obturated with gutta percha and AH26 sealer. Experimental sections were treated similarly except they were placed in 2% CHX for 10 minutes prior to obturation. Control specimens were divided into 4 control groups and stored in saline for 1 day, 3 weeks, 6 weeks, and 12 weeks. Experimental specimens were divided into 4 groups and stored in saline for 1 day, 3 weeks, 6 weeks, and 12 weeks. After their respective storage periods, all specimens were halved and canal wall dentin was ground out with Peeso reamers. Dentin specimens were agitated in 700 microl of saline for 5 hours to release CHX. After centrifugation the supernatants were analyzed with UV spectrophotometry at 253 nm. To determine whether the CHX from dentin samples remained antimicrobial, the extracts from experimental and control groups were mixed with cultures of Enterococcus faecalis. RESULTS: After 1 day of storage, the dentin extract contained approximately 0.0048% CHX. After 3, 6 and 12 weeks, dentin extracts contained approximately 0.0023%, 0.0016%, and 0.0010% CHX respectively. Extracts from the storage groups were found to be highly antimicrobial corresponding to the CHX concentration. CONCLUSION: The results of this study indicate that CHX is retained in root canal dentin in antimicrobially effective amounts for up to 12 weeks.

Animals↗

PubMed2003

The effect of chlorhexidine as an endodontic disinfectant.

OBJECTIVE: The purpose of this study was to establish whether addition of a 2% chlorhexidine rinse to a conventional treatment protocol enhances the rate of the successful disinfection of the root canal system in vivo. STUDY DESIGN: Twenty-four teeth with infected necrotic pulps and resorbing apical periodontitis were treated with a conventional technique in which 1% NaOCl as irrigant was used. Half of the cases received an additional rinse with 2% chlorhexidine. Prereduced thioglycollate medium was used to take cultures that were incubated for 4 weeks. RESULTS: Cultivable bacteria were retrieved at the conclusion of the first visit in 1 out of 12 chlorhexidine cases whereas in the control group 7 out of 12 cases showed growth. This difference was significant (P < .05). CONCLUSION: The findings are clinically important.

Adolescent↗

PubMed2003

Cell and tissue reactions to mineral trioxide aggregate and Portland cement.

OBJECTIVE: Mineral trioxide aggregate (MTA) is being widely used for root-end fillings, pulp capping, perforation repairs, and other endodontic procedures. MTA and Portland cement (PC) have many similar physical, chemical, and biologic properties. PC cement has shown promising potential as an endodontic material in several studies in vitro and in vivo. The purpose of this study was to compare the cytotoxic effect in vitro and the tissue reaction of MTA and Portland cement in bone implantation in the mandibles of guinea pigs. STUDY DESIGN: Millipore culture plate inserts with freshly mixed or set material were placed into the culture plates with already attached L929 cells. After an incubation period of 3 days, the cell morphology and cell counts were studied. Adult male guinea pigs under strict asepsis were anesthetized, during which a submandibular incision was made to expose the symphysis of the mandible. Bilateral bone cavities were prepared and Teflon applicators with freshly mixed materials were inserted into the bone cavities. Each animal received 2 implants, one filled with ProRoot and 1 with PC. The animals were killed after 2 or 12 weeks, and the tissues were processed for histologic evaluation by means of light microscopy. RESULTS: There was no difference in cell reactions in vitro. Bone healing and minimal inflammatory response adjacent to ProRoot and PC implants were observed in both experimental periods, suggesting that both materials are well tolerated. CONCLUSIONS: MTA and PC show comparative biocompatibility when evaluated in vitro and in vivo. The results suggest that PC has the potential to be used as a less expensive root-end filling material.

Aluminum Compounds↗