Rajeswari C L, Kumar M V Sunil
Department of Prosthodontics, KLE Society's Institute of Dental Sciences Bangalore, Bengaluru, Karnataka, India.
Department of Prosthodontics, Jaipur Dental College, Jaipur, Rajasthan, India.
J Indian Prosthodont Soc. 2015 Jan-Mar;15(1):39-45. doi: 10.4103/0972-4052.155039.
In the inaccessible areas on the crown the removal of calculus and stains by hand and ultrasonic instrumentation is the method for cleaning to preserve and increase the longevity of the restoration. However, when oral prophylaxis is performed on restorative crowns, it may produce some surface alterations and may favour plaque accumulation.
Many patients may have restored their teeth with artificial crowns and would come to the dental office for oral prophylaxis. If a routine oral prophylaxis is followed, its effect on the restorative materials and the plaque accumulation can be studied.
A total of 15 disc shaped wax patterns were invested and casted for cast titanium (Group A) and the remaining 15 disk shaped for nickel-chromium (Group B). The obtained castings were finished and polished. All the specimens were subjected to hand and ultrasonic scaling for 15 s. Profilometer and scanning electron microscopic was used to analyze and evaluate the surface roughness. Specimens of each group were embedded on the anterior lingual aspects of the removable lower retention plates. 5 volunteers were asked to wear it in the mouth for 24 h for 7 days. After 7 days, the specimens were stained with plaque disclosing solutions and the photomicrographs were taken by the optical stereomicroscope and the plaque accumulations were assessed in percentage.
The difference in average surface roughness (μm) of the polished test specimens was maximum for ultrasonic scaling than hand scaling and maximum for Group A than Group B. Plaque accumulation in percentage on the treated specimens was found to be nonsignificant but, mean plaque accumulation was maximum on ultrasonic scaling surface than hand scaling and maximum for Group A than Group B. Surface roughness was found to be statistically significant after hand scaling (F = 9.377, P = 0.000) and ultrasonic scaling (F = 5.373, P = 0.0000) by Student t-test.
The Surface roughness and plaque accumulation on the specimens were more for Group A than Group B and maximum produced by ultrasonic scaling than hand scaling.
在牙冠难以触及的区域,通过手工和超声器械去除牙结石和污渍是保持和延长修复体使用寿命的清洁方法。然而,对修复性牙冠进行口腔预防时,可能会产生一些表面改变,并可能有利于牙菌斑的积聚。
许多患者可能已用人造牙冠修复牙齿,并会前往牙科诊所进行口腔预防。如果遵循常规口腔预防措施,就可以研究其对修复材料和牙菌斑积聚的影响。
共制作15个圆盘形蜡型,用于铸造钛合金(A组),另外15个圆盘形用于铸造镍铬合金(B组)。对获得的铸件进行精加工和抛光。所有标本均进行15秒的手工和超声洁治。使用轮廓仪和扫描电子显微镜分析和评估表面粗糙度。将每组标本嵌入可摘取下颌固位板的前舌侧。邀请5名志愿者在口腔中佩戴7天,每天佩戴24小时。7天后,用牙菌斑显示剂对标本进行染色,并用光学体视显微镜拍摄显微照片,以百分比评估牙菌斑积聚情况。
超声洁治后的抛光测试标本平均表面粗糙度(μm)差异比手工洁治时大,A组比B组大。经处理的标本上牙菌斑积聚的百分比差异不显著,但超声洁治表面的平均牙菌斑积聚比手工洁治时多,A组比B组多。经学生t检验,手工洁治(F = 9.377,P = 0.000)和超声洁治(F = 5.373,P = 0.0000)后表面粗糙度具有统计学意义。
A组标本的表面粗糙度和牙菌斑积聚比B组多,超声洁治产生的表面粗糙度和牙菌斑积聚比手工洁治时大。