Microfracture artifacts and their role in electron microscopic evaluation of endodontically treated human teeth
Date
1978
DOI
Authors
Blumenkranz, Uziel
Version
OA Version
Citation
Abstract
Recent literature has reported the possible occurrence of microfractures during endodontic procedures. An assumption was made that microfractures, in scanning electron microscopy examination of dentinal walls, may have been produced by pressure generated during the use of vertical compaction of warm gutta percha (Wollard et al 1976). Previous studies have indicated that it is impossible to produce visible fractures in teeth, with the amount of pressure transmitted to the gutta percha by manual application of plugging instruments against the gutta-percha itself (Cohen J. 1974). Of course, the application of pressure, by wedging steel pluggers and or spreaders, against the dentinal walls as in lateral condensation is contrary to the vertical compaction of warm gutta-percha technique. The purpose of the present investigation was to determine whether microfractures could be produced during vertical compaction of warm gutta-percha. It became apparent early in the investigation, that microfractures could be found in dentin walls of teeth subjected to all endodontic filling techniques, and equally important, in dentinal walls of extracted teeth that had not been subjected to any endodontic filling procedures at all.
Preliminary investigation provided the impression that microfractures previously reported may have been related to artifacts due to:
(a) microfractures previously existent in extracted teeth,
or
(b) microfractures produced during preparation of specimen for scanning electron microscopy examination.
In order to overcome possible errors in in vitro studies, it was decided to perform endodontic treatment under clinical conditions rather than on extracted teeth. Following endodontic treatment these teeth were extracted and sectioned. A replication technique for scanning electron microscopy was employed in order to avoid dehydration artifacts of the original specimen. It was observed that dehydration artifacts could cause cracking of dentin. The replicas which were made prior to dehydration demonstrated no evidence of cracks however. Repeated replication, causing the sample to be exposed to air for prolonged periods of time resulted in cracking of one original sample which was duplicated in the replica. Successful first replicas of fresh specimens failed to show any evidence of fractures.
Description
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Colored photographs included.
Thesis (M.Sc.D.)--Boston University, Henry M. Goldman School of Graduate Dentistry, 1978 (Endodontics)
Bibliography : leaves 77-86.
Colored photographs included.
Thesis (M.Sc.D.)--Boston University, Henry M. Goldman School of Graduate Dentistry, 1978 (Endodontics)
Bibliography : leaves 77-86.
License
This work is protected by copyright. Downloading is restricted to the BU community. If you are the author of this work and would like to make it publicly available, please contact open-help@bu.edu.