Tanaka Junko, Mukai Norio, Tanaka Muto, Tanaka Masahiro
Department of Fixed Prosthodontics and Occlusion, Osaka Dental University, 1-5-17, Otemae, Chuo-ku, Osaka 540-0008, Japan.
Int J Dent. 2012;2012:452108. doi: 10.1155/2012/452108. Epub 2012 Jan 11.
Objective. The purpose of this study was to investigate whether teeth that have undergone prosthetic restoration are under conditions that promote caries recurrence. Methods. The subjects were 20 dentate adults with both a healthy tooth and an affected tooth entirely covered with a complete cast crown in the molar regions of the same arch. The pH was measured in plaque adhering to the margin of the tooth covered with a complete cast crown and adhering to the cervicobuccal area of the natural tooth. In addition, the numbers of cariogenic bacteria (mutans streptococci and lactobacilli) were measured employing the saliva test. The relationships between the number of cariogenic bacteria and plaque pH of the natural tooth and between the number of cariogenic bacteria and plaque pH of the tooth covered with a complete cast crown were investigated. Results. The plaque pH of the tooth covered with a complete cast crown decreased as the numbers of SM and LB increased. The natural tooth were also influenced by the number of SM. Conclusion. Secondary caries are likely to develop from the marginal region of the crown in the oral cavity with a high caries risk unless a preventive program is prepared and the oral environment is improved following the program.
目的。本研究旨在调查经过修复治疗的牙齿是否处于促进龋齿复发的条件下。方法。研究对象为20名有牙成年人，在同一牙弓的磨牙区域有一颗健康牙齿和一颗完全被铸造全冠覆盖的患牙。测量附着在被铸造全冠覆盖牙齿边缘的菌斑以及附着在天然牙颈颊区域的菌斑的pH值。此外，采用唾液检测法测量致龋菌（变形链球菌和乳酸杆菌）的数量。研究天然牙的致龋菌数量与菌斑pH值之间以及被铸造全冠覆盖牙齿的致龋菌数量与菌斑pH值之间的关系。结果。随着变形链球菌（SM）和乳酸杆菌（LB）数量的增加，被铸造全冠覆盖牙齿的菌斑pH值降低。天然牙也受到变形链球菌数量的影响。结论。在龋齿风险较高的口腔环境中，除非制定预防方案并按照该方案改善口腔环境，否则继发龋很可能从牙冠边缘区域发展而来。
