The impact of post preparation on the residual dentin thickness of maxillary molars
Section snippets
Material and Methods
This in vitro repeated-measure study, approved by the ethical committee at the University Center of Maranhão, included 15 teeth from a pool of 33 first maxillary molars, selected according to the radiographic mesiodistal thickness of the palatal root. A sequence of intracanal preparations was performed on the palatal root. After each preparation stage for post placement (before preparation, after hand instrumentation, after Largo reamer enlargement, and after ParaPost preparation) standardized
Results
Table I shows means and standard deviations for RDT on each post space wall and at sectioned levels after each stage of the preparation for post placement. The 3-way ANOVA (Table II) indicated a significant reduction in RDT after each stage of the post space preparation at both levels (P<.001). Comparing the levels, a significant difference in dentin reduction was detected only after the use of a ParaPost drill; here the reduction was significantly higher at the apical level than at the coronal
Discussion
A significant difference in the RDT of root canal walls at both levels was observed after post preparation with the ParaPost system. Thus the null hypothesis was rejected. A significant reduction in RDT after each stage of preparation for post placement at the palatal root of maxillary molars at both levels was observed (P<.001). This is consistent with previous studies that demonstrated a significant reduction in RDT after the subsequent stages for post preparation using the ParaPost System.5,
Conclusion
Within the limitations of this in vitro study, intracanal preparation up to a parallel-sided ParaPost 5.0 drill increased the risk of perforation or weakening of the root in the buccal and palatal aspects, especially at the apical level.
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Cited by (22)
Cone beam computed tomography analysis of residual dentin thickness after virtual post placement in the palatal roots of maxillary first molars
2022, Journal of Prosthetic DentistryCitation Excerpt :The percentage of molars with inadequate or no RDT was approximately 85.7% when the largest post size (1.14 mm) was examined at 5 mm from the apex. These findings are consistent with those of a previous study when a larger post size (1.25 mm) was compared, although the sample size was smaller.24 In contrast with previous in vitro studies,5,22-24,27 the present investigation assessed the use of posts in palatal roots without using extracted teeth.
Remaining dentinal thickness after simulated post space preparation and the fit of prefabricated posts to root canal preparation shapes
2021, Journal of the American Dental AssociationCitation Excerpt :Additional studies with other assumptions and their permutations are suggested in association with the assessment of progressive root morphology in other populations. We highlighted that, if posts are placed to 5 mm from the apical terminus, particular canals demonstrate higher levels of likelihood of violating the 1-mm rule, which can be interpreted as a proportionate risk of experiencing perforation or future root fracture, which is in agreement with other studies.27,28 Therefore, there is a higher risk of sustaining iatrogenic damage when preparing for a post in mandibular incisors and buccal and distal canals of molars.29
Microcomputer tomography measurement of minimum residual dentin thickness in mandibular first molars after virtual fiber post placement
2020, Journal of Prosthetic DentistryCitation Excerpt :In this study, the mean mRDT at the mesial side of distal roots was less than 1 mm (0.95 ±0.35 mm) after root canal preparation, and after post placement, the values were 0.76 ±0.34 mm for post #1, 0.63 ±0.35 mm for post #2, 0.52 ±0.35 mm for post #3, and 0.41 ±0.33 mm for post #4, which was acceptable for clinical application. Root anatomy is another important factor affecting RDT, which gradually decreases with the distance from the root canal orifice.6-8 The presence of oval roots with a buccolingual diameter much wider than the mesial-distal diameter is another factor affecting RDT.10,27,29,30
Influence of adhesive techniques on fracture resistance of endodontically treated premolars with various residual wall thicknesses
2013, Journal of Prosthetic Dentistry
Presented at the International Association for Dental Research (IADR) annual meeting, Barcelona, Spain, July 2010.