published_or_final_version / abstract / Dentistry / Master / Master of Dental Surgery

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Dentistry Johannesburg, 2013 / The aim of this study was to test various alternating sequences of sodium hypochlorite (NaOCl), anolyte solution, and EDTA for their ability to remove the mineralised portion of the smear layer, and to destroy bacteria. Forty-eight single canal teeth were collected and randomly divided into six groups, prepared to working length, sterilized and inoculated with Enterococcus faecalis. The irrigation protocols were as follows: Group 1 (four roots) 3ml sterile distilled water, Group 2 (four roots) 3ml 6% sodium hypochlorite, Group 3 (ten roots) 3ml 6% sodium hypochlorite followed by 3ml 18% EDTA, Group 4 (ten roots) 3ml 6% sodium hypochlorite followed by 5ml anolyte solution, Group 5 (ten roots) 0.5ml 6% sodium hypochlorite followed by 5ml anolyte solution followed by 3ml 18% EDTA and Group 6 (ten roots) 5ml anolyte solution followed by 3ml 18% EDTA. Sterile paper points were inserted into the canals after sterilization, inoculation and irrigation. Standard cultivation techniques were used to count the colony forming units of viable bacteria at each phase. The roots were split longitudinally and prepared for SEM evaluation. Two photomicrographs were randomly taken in the coronal, middle and iv apical thirds of each root and the number of patent dentinal tubules counted. The One-way ANOVA was used for statistical evaluation. The small sample size limited definitive conclusions but the results indicated that the coronal thirds of the roots showed better smear layer removal than the apical thirds, Sodium hypochlorite followed by EDTA showed the best smear layer removal. The various sequences of NaOCl, anolyte solution, and EDTA all had similar antibacterial results.

Thesis (M.D.S.)--University of Hong Kong, 1993. / Includes bibliographical references (p. 105-125). Also available in print.

Thesis (Ph. D.)--University of Hong Kong, 2005. / Also available in print.

Thesis (M. D. S.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

This study assessed biofilm formation within sealer-dentin interfaces of root segments filled with gutta-percha and zinc oxide sealer incorporated with chitosan nanoparticles, without and with canal surface treatments. Bovine root segments were filled using Pulp Canal Sealer incorporating chitosan nanoparticles (CS), or after surface treatment with phosphorylated CS (PHCS), chitosan-conjugated Rose Bengal (CSRB) and a combination of both (RBPH). The control group used unmodified sealer. Specimens were aged 1- or 4-weeks. Enterococcus faecalis biofilms were grown on specimens for 7days and assessed with confocal laser scanning microscopy. In the 4-week aged specimens only, the mean biofilm areas were lower than the control for CS, PHCS and RBPH. Percentage of biofilm-covered interface was lower than the control for CS and PHCS. CS, PHCS and RBPH did not differ. Incorporating chitosan nanoparticles into sealer affected inhibition of biofilm formation within the sealer-dentin interface. This was maintained with PHCS, but moderated by CSRB.

This study assessed biofilm formation within sealer-dentin interfaces of root segments filled with gutta-percha and zinc oxide sealer incorporated with chitosan nanoparticles, without and with canal surface treatments. Bovine root segments were filled using Pulp Canal Sealer incorporating chitosan nanoparticles (CS), or after surface treatment with phosphorylated CS (PHCS), chitosan-conjugated Rose Bengal (CSRB) and a combination of both (RBPH). The control group used unmodified sealer. Specimens were aged 1- or 4-weeks. Enterococcus faecalis biofilms were grown on specimens for 7days and assessed with confocal laser scanning microscopy. In the 4-week aged specimens only, the mean biofilm areas were lower than the control for CS, PHCS and RBPH. Percentage of biofilm-covered interface was lower than the control for CS and PHCS. CS, PHCS and RBPH did not differ. Incorporating chitosan nanoparticles into sealer affected inhibition of biofilm formation within the sealer-dentin interface. This was maintained with PHCS, but moderated by CSRB.

Thesis (M.Sc.(Odontology))--University of Pretoria, 2009. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, Ann Arbor, 1983. / Typescript (photocopy). Includes bibliographical references (leaves 55-61). Also issued in print.

Thesis (M.S.)--University of Michigan, 1968.