Soares Janir Alves, de Carvalho Maria Auxiliadora Roque, Soares Suelleng Maria Cunha Santos, Pereira Rodrigo Dantas, Brito-Júnior Manoel, Magalhães Paula Prazeres, Nunes Isabel Alessandra Miranda, Tavarez Rudys Rodolpho de Jesus, Rizzi Claudia de Castro, Moreira Rafaela Nogueira, Farias Luiz de Macêdo, Maia Filho Etevaldo Matos
Department of Dentistry, Federal University of the Jequitinhonha and Mucuri Valleys, Diamantina, Minas Gerais, Brazil.
Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
ScientificWorldJournal. 2019 Jan 1;2019:9219238. doi: 10.1155/2019/9219238. eCollection 2019.
To quantify density in root canal dentin after chemomechanical preparation (CMP) using alternated irrigating regimen.
Root canals (RC) were contaminated with (ATCC 19433) for 3 weeks and evident biofilms were obtained. After initial sampling (S1), the CMP was aided by irrigants: saline solution (control; n=12), a conventional regimen (CR) (group 1; n=12) using 5.25% NaOCl and a final rinse with 17% EDTA, and an alternating regimen (AR) of intercalated use of NaOCl and EDTA (group 2, n=12), followed by a second sampling (S2). After 2 weeks, S3 was obtained. Two roots were analyzed by scanning electron microscopy. Each root was divided into cervical, mild, and apical segments and sampling of the superficial (n=90) and deep (n=90) dentin layers was obtained using Gates-Glidden burs. The density (CFU/mg) in log was categorized as residual (0 > 0.2), moderate (0.2 ≥ 0.5), or elevated (> 0.5). The prevalence of positive samples in BHI and BHI-A was analyzed by Pearson's chi-square test. The data were normalized by a log transformation of CFU and were analyzed by one-way ANOVA and Tukey's tests.
Biofilms were observed only in the control root canal walls. Topographically, the controls and CR showed similar distributions of in the dentin. Microbiologically positive root canals harbored much in the adjacent dentin ( < 0.05). Irrigating saline provided moderate density of in the dentin while CR and AR resulted in a residual density of microorganisms ( < 0.05).
The density in dentin was influenced by the irrigating regimen and the microbiological status of the root canal. The CMP aided by the alternating regimen interfered with the recolonization of the root canal and topographic distribution of in root dentin.
使用交替冲洗方案对化学机械预备（CMP）后根管牙本质中的细菌密度进行定量分析。
根管（RC）用粪肠球菌（ATCC 19433）污染3周以获得明显的生物膜。在初始取样（S1）后，使用冲洗液辅助进行CMP：生理盐水（对照组；n = 12）、传统方案（CR）（第1组；n = 12），使用5.25%次氯酸钠并最终用17%乙二胺四乙酸（EDTA）冲洗，以及交替使用次氯酸钠和EDTA的交替方案（AR）（第2组，n = 12），随后进行第二次取样（S2）。2周后，获取S3。通过扫描电子显微镜分析两根根管。每根根管分为颈段、中段和根尖段，使用盖茨 - 格利登钻针从浅表（n = 90）和深层（n = 90）牙本质层取样。以对数形式表示的细菌密度（CFU/mg）分为残留（0＞0.2）、中度（0.2≥0.5）或升高（＞0.5）。通过Pearson卡方检验分析脑心浸液（BHI）和添加放线菌酮的脑心浸液（BHI - A）中阳性样本的患病率。数据通过对CFU进行对数转换进行归一化，并通过单因素方差分析和Tukey检验进行分析。
仅在对照根管壁观察到生物膜。在地形学上，对照组和CR组在牙本质中的细菌分布相似。微生物学上呈阳性的根管在相邻牙本质中存在更多细菌（P＜0.05）。冲洗生理盐水在牙本质中产生中度细菌密度，而CR和AR导致微生物残留密度（P＜0.05）。
牙本质中的细菌密度受冲洗方案和根管微生物学状态的影响。交替方案辅助的CMP干扰了根管的再定植以及根管牙本质中细菌的地形分布。
