Department of Endodontics, School of Stomatology, Tianjin Medical University, Tianjin, China.
Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China.
Int Endod J. 2023 May;56(5):608-621. doi: 10.1111/iej.13890. Epub 2023 Jan 31.
Microbial function changes may be responsible for dental pulp transformation from normal to diseased. However, studies on the prediction and verification of the function of the microbial community in the deep dentine and pulp of caries-induced pulpitis are lacking.
This study included 171 cases of deep dentinal caries divided into normal pulp (NP), reversible pulpitis (RP), and irreversible pulpitis (IRP). In Experiment I, the microbial community composition was identified in 111 samples using 16S ribosomal DNA. Function prediction was performed through phylogenetic investigation of communities by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States prediction and qPCR. In Experiment II, different microbiome functions were confirmed in 60 samples using liquid chromatography-tandem mass spectrometry.
In Experiment I, microbial abundance significantly differed in the IRP group compared to the other two groups. The RP and NP groups had the same microbiome composition, but the predicted functional difference between the RP and NP groups pertained to membrane transport (p < .010). The predicted functional difference between the IRP and NP groups pertained to amino-acid, co-factor, and vitamin metabolism (p < .010). In Experiment II, Kyoto Encyclopedia of Genes and Genomes functional annotation revealed that the differential metabolites between the RP and NP groups did not participate in membrane transport; however, the differential metabolites between the IRP and NP groups participated in amino-acid metabolism.
The near-pulp microbiome in RP and NP with deep dentinal caries had the same differential function. However, amino acid metabolism in near the pulp microbial community differed between IRP and NP with deep dentinal caries.
微生物功能的变化可能是导致正常牙髓转变为病变牙髓的原因。然而，目前缺乏关于龋源性牙髓炎深牙本质和牙髓中微生物群落功能预测和验证的研究。
本研究纳入了 171 例深牙本质龋患者，分为正常牙髓（NP）、可复性牙髓炎（RP）和不可复性牙髓炎（IRP）。在实验 I 中，通过 16S 核糖体 DNA 鉴定了 111 个样本的微生物群落组成，通过 Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 预测和 qPCR 进行功能预测。在实验 II 中，通过液相色谱-串联质谱法在 60 个样本中确认了不同的微生物组功能。
在实验 I 中，IRP 组与其他两组相比，微生物丰度差异显著。RP 和 NP 组具有相同的微生物群落组成，但 RP 和 NP 组之间的预测功能差异与膜转运有关（p <.010）。IRP 和 NP 组之间的预测功能差异与氨基酸、辅助因子和维生素代谢有关（p <.010）。在实验 II 中，京都基因与基因组百科全书功能注释显示，RP 和 NP 组之间的差异代谢物不参与膜转运；然而，IRP 和 NP 组之间的差异代谢物参与了氨基酸代谢。
深牙本质龋中 RP 和 NP 的近牙髓微生物群具有相同的差异功能。然而，深牙本质龋中 IRP 和 NP 的近牙髓微生物群落中的氨基酸代谢存在差异。
