Rajan Sadna, Day Peter F, Christmas Clare, Munyombwe Theresa, Duggal Monty, Rodd Helen D
Department of Paediatric Dentistry, Leeds Dental Institute, University of Leeds, Leeds, UK.
Int J Paediatr Dent. 2014 Jul;24(4):268-76. doi: 10.1111/ipd.12070. Epub 2013 Oct 17.
This study sought to investigate the effect of caries, in association with physiological root resorption, on the pulpal status of human primary molars.
Fifty-three mandibular primary molars were obtained from children requiring extractions under general anaesthesia. Following extraction, teeth were split longitudinally and placed in Zamboni's fixative. Teeth were categorised according to i) the depth of caries (less than or greater than halfway through dentine thickness) and ii) the degree of physiological root resorption (<33%, 34-66% or >67% of the root length). Ten-micrometre pulp sections were subject to indirect immunofluorescence using a combination of PGP 9.5 (a general neuronal marker), CD45 (a general neuronal marker), and Ulex europaeus agglutinin I (a marker of vascular endothelium). Image analysis was used to determine the percentage area of staining (PAS) for innervation and immune cells.
Marked differences were seen between different samples, but there were no significant differences in mean PAS for PGP 9.5 or CD45 according to the degree of caries or extent of physiological root resorption (two-way anova, P > 0.05).
Findings suggest that even if primary molars are undergoing exfoliation, they show comparable caries-induced changes to teeth without physiological root resorption, thus retaining potential for healing and repair.
本研究旨在调查龋齿与生理性牙根吸收对人类乳磨牙牙髓状态的影响。
从需要全身麻醉下拔牙的儿童中获取53颗下颌乳磨牙。拔牙后,将牙齿纵向劈开并置于赞博尼固定液中。根据以下标准对牙齿进行分类:i)龋损深度(小于或大于牙本质厚度的一半)和ii)生理性牙根吸收程度(牙根长度的<33%、34 - 66%或>67%)。使用PGP 9.5(一种通用神经元标记物)、CD45(一种通用神经元标记物)和荆豆凝集素I(血管内皮标记物)的组合对10微米厚的牙髓切片进行间接免疫荧光检测。图像分析用于确定神经支配和免疫细胞的染色面积百分比(PAS)。
不同样本之间存在明显差异,但根据龋损程度或生理性牙根吸收程度,PGP 9.5或CD45的平均PAS无显著差异(双向方差分析,P>0.05)。
研究结果表明,即使乳磨牙正在脱落,它们与没有生理性牙根吸收的牙齿相比,龋损引起的变化相似,因此仍具有愈合和修复的潜力。