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Evaluating the Effect of Abrasive Microparticle Root Canal Irrigants on Dentin Microhardness: An In Vitro Comparative
Taif R Ghafil1, Hussain F Al-Huwaizi2
1Department of Restorative and Aesthetic Dentistry, College of Dentistry, University of Baghdad, Baghdad, Baghdad Governorate, Iraq.
Aim:
To evaluate the effect of zirconia microparticle irrigation solution on dentin microhardness by particle size, weight, and ultrasonic activation (UA) time, comparing its effect with ethylenediaminetetraacetic acid (EDTA).
Materials And Methods:
A total of 112 palatal roots of maxillary first molars were instrumented up to 40, 06 and divided into four primary groups according to the irrigation protocol: Group A zirconium oxide (5 μm) subdivided according to the UA time (1, 2.5, and 5 minutes) and powder weight [50 mg and 100 mg per 10 mL normal saline (NS)] into six subgroups (A1-A6), n = 8 for each subgroup, group B zirconium oxide (10 μm) also subdivided according to the UA times and powder weight into six subgroups (B1-B6), n = 8 for each subgroup, group C EDTA 17%, (n = 8), group D normal saline, (n = 8). The roots were sectioned longitudinally into two halves, then three points within each half were examined, corresponding to the coronal, middle, and apical. Vickers microhardness tests were completed, including three measurements at three points on each half, and the mean value of the three measurements within each half was taken. The repeated-measures and one-way analysis of variance (ANOVA) tests were used for assessing the microhardness. Dunnett's two-sided test was used for multiple comparisons.
Results:
Most subgroups exhibited higher microhardness mean values than EDTA; however, a statistically significant difference was observed only at the apical third of subgroup A6.
Conclusion:
The abrasive irrigant, under specific powder weight, particle size, and UA time, resulted in higher Vickers hardness (VHN) values.
Clinical Significance:
Substituting EDTA with an abrasive irrigant may increase dentin microhardness, which could contribute to improved resistance to structural degradation and enhance the longevity of endodontically treated teeth. Dentin microhardness may be better preserved by abrasive irrigants than by traditional chelating agents. For teeth to remain strong and structurally sound, dentin hardness must be maintained. Over-softening may make fractures more likely. Clinical results are enhanced, and long-term durability is supported by using irrigants with few side effects.
