Khakhar Pooja, Katge Farhin, Krishna Vamsi, Pradhan Debapriya, Shetty Shilpa, Patil Devendra
Postgraduate Student, Dept. of Pediatric and Preventive Dentistry, Terna Dental College, Phase- II, Sector- 22, Nerul (west), Navi Mumbai, India.
Dept. of Pediatric and Preventive Dentistry, Terna Dental College, Phase - II, Sector- 22, Nerul (west), Navi Mumbai, India.
J Dent (Shiraz). 2024 Dec 1;25(4):326-333. doi: 10.30476/dentjods.2023.96668.1955. eCollection 2024 Dec.
Root canal preparation with rotary files causes dentinal cracks in root canals of primary teeth affecting their longevity.
Nickel-titanium rotary files have been widely used for root canal preparation in primary teeth. The present study compared occurrence of dentinal microcracks in root canals of extracted primary molar teeth prepared using Hedstrom (H) files, ProTaper Universal rotary files, and ProTaper Next rotary file systems.
In this experimental study, 80 primary molar mesial root canals were randomly divided into four groups of 20 canals each (n=20). Group I was prepared with H files. Group II was prepared with ProTaper Universal rotary files using shaping files SX and S2. Group III was instrumented with ProTaper Next rotary files X1 and X2 while Group IV was left unprepared and served as control. Roots were stained with 1% methylene blue solution and sectioned perpendicular to the long axis at 2mm, 4mm, and 6mm from the apical foramen. Slices obtained were examined under the stereomicroscope. Data obtained were subjected to statistical analysis using chi square tests.
Dentinal microcracks were observed in groups prepared using H files, ProTaper Universal, and ProTaper Next rotary files. Highest percentage of cracked root canals (20%) was seen in Group I, prepared by H files. These cracks were complete in nature, found in apical sections and statistically significant (= 0.016). Group III prepared with ProTaper Next showed 10% dentinal cracks, followed by ProTaper Universal group with 5% cracked root canals.
H files may be considered more aggressive at apical third due to complete cracks produced.
使用旋转锉进行根管预备会导致乳牙根管出现牙本质裂纹，影响其使用寿命。
镍钛旋转锉已广泛用于乳牙根管预备。本研究比较了使用Hedstrom（H）锉、ProTaper Universal旋转锉和ProTaper Next旋转锉系统对拔除的乳磨牙根管进行预备后牙本质微裂纹的发生率。
在本实验研究中，80个乳磨牙近中根管被随机分为四组，每组20个根管（n = 20）。第一组使用H锉进行预备。第二组使用ProTaper Universal旋转锉，采用SX和S2成形锉进行预备。第三组使用ProTaper Next旋转锉X1和X2进行预备，而第四组未进行预备作为对照。将牙根用1%亚甲蓝溶液染色，并在距根尖孔2mm、4mm和6mm处垂直于长轴进行切片。在体视显微镜下检查获得的切片。对获得的数据使用卡方检验进行统计分析。
在使用H锉、ProTaper Universal和ProTaper Next旋转锉预备的组中均观察到牙本质微裂纹。在使用H锉预备的第一组中，根管裂纹的发生率最高（20%）。这些裂纹是完全性的，出现在根尖切片中，且具有统计学意义（P = 0.016）。使用ProTaper Next预备的第三组显示10%的牙本质裂纹，其次是ProTaper Universal组，有5%的根管出现裂纹。
由于产生了完全性裂纹，H锉在根尖三分之一处可能被认为更具侵袭性。
