Abstract:
:The destabilizing effect of endodontic treatment upon teeth is still controversial. The purpose of this study was to investigate the effects of different steps of endodontic treatments upon the rigidity of teeth. Extracted untreated central maxillary anterior teeth were loaded (3.75 N), and deformations of the root were assessed by Speckle pattern interferometry. The following treatments (with subsequent determination of deformability) were conducted sequentially: access preparation, manual instrumentation (Kerr files ISO-40, ISO-60, ISO-80, ISO-110), and tapered and parallel-sided post preparation. It was found that the teeth were increasingly destabilized by any treatment. While the increased deformability was not significant with the manual enlargement (p > 0.05), we found a significant destabilization after access preparation and post preparation (p < 0.05). A corresponding difference was found after conversion of the post preparation from tapered to parallel-sided (p < 0.05). Both substance loss and modifications of the natural root canal geometry play an important role in tooth rigidity.
journal_name
J Dent Resjournal_title
Journal of dental researchauthors
Lang H,Korkmaz Y,Schneider K,Raab WHdoi
10.1177/154405910608500416keywords:
subject
Has Abstractpub_date
2006-04-01 00:00:00pages
364-8issue
4eissn
0022-0345issn
1544-0591pii
85/4/364journal_volume
85pub_type
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