J Korean Acad Conserv Dent.  2011 Sep;36(5):425-430. 10.5395/JKACD.2011.36.5.425.

The effects of short-term application of calcium hydroxide on dentin fracture strength

• Shin EJ
• Park YJ
• Lee BN
• Jang JH
• Chang HS
• Hwang IN
• Oh WM
• Hwang YC

• KMID: 2176580
• DOI: http://doi.org/10.5395/JKACD.2011.36.5.425

Abstract

OBJECTIVES
This in vitro study investigated whether short-term application of calcium hydroxide in the root canal system for 1 and 4 wk affects the fracture strength of human permanent teeth.
MATERIALS AND METHODS
Thirty two mature human single rooted mandibular premolars in similar size and dentin thickness without decay or restorations were hand and rotary instrumented and 16 teeth vertically packed with calcium hydroxide paste and sealed coronally with caviton to imitate the endodontic procedure and the other 16 teeth was left empty as a control group. The apicies of all the samples were sealed with resin, submerged in normal saline and put in a storage box at 37degrees C to mimic the oral environment. After 1 and 4 wk, 8 samples out of 16 samples from each group were removed from the storage box and fracture strength test was performed. The maximum load required to fracture the samples was recorded and data were analysed statistically by the two way ANOVA test at 5% significance level.
RESULTS
The mean fracture strengths of two groups after 1 wk and 4 wk were similar. The intracanal placement of calcium hydroxide weakened the fracture strength of teeth by 8.2% after 4 wk: an average of 39.23 MPa for no treatment group and 36.01 MPa for CH group. However there was no statistically significant difference between experimental groups and between time intervals.
CONCLUSIONS
These results suggest that short term calcium hydroxide application is available during endodontic treatment.

Keyword

Calcium hydroxide; Dentin; Fracture strength; Short term application

MeSH Terms

Bicuspid
Calcium
Calcium Hydroxide
Calcium Sulfate
Dental Cements
Dental Pulp Cavity
Dentin
Hand
Humans
Hydrazines
Hydroxides
Root Canal Filling Materials
Tooth
Vinyl Compounds
Zinc Oxide
Calcium
Calcium Hydroxide
Calcium Sulfate
Dental Cements
Hydrazines
Hydroxides
Root Canal Filling Materials
Vinyl Compounds
Zinc Oxide

Figure

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  Figure 1 The samples were fixed into a vice and the load was applied at 90° anlge to long axis of the tooth at 5 mm/min by cross-head speed.

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  Figure 2 The mean fracture strength of test groups. There was no statistically significant difference between experimental groups and between time intervals (p > 0.05). No tx, no treatment; CH, calcium hydroxide treatment.

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  Figure 3 Most of fracture was happened in cervical area of tooth.

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