Veitz-Keenan Analia, Keenan James R
New York College of Dentistry, New York, USA.
Evid Based Dent. 2017 Mar;18(1):21-22. doi: 10.1038/sj.ebd.6401222.
Data sourcesA broad computerised search with similar key terms was performed in different databases that included: Ovid Medline, Thomson's ISI Web of Science, PubMed, Science Direct, EMBASE and the Cochrane Library. Grey literature, dissertations, abstracts and theses were searched too. Reference lists of the selected articles were hand-searched.Study selectionThe inclusion criteria included in vivo randomised clinical trials and quasi-randomised clinical trials using gingival retraction techniques with and without cord. Studies were included if they examined the primary outcome from the review: efficiency of haemostasis control, the amount of gingival displacement and the influence of the techniques on gingival/periodontal health. Secondary outcomes accepted for the review included subjective factors reported by the patient such as pain, sensitivity, unpleasant taste and discomfort and operator's experience with both techniques. Non-English papers, clinical reports, animals studies or in vitro studies were excluded.Data extraction and synthesisTwo authors independently searched and screened the articles. Disagreements were resolved by discussion. A third reviewer participated in the eligibility of the studies. The risk of bias was assessed using the Cochrane Collaboration tool. Due to the heterogeneity of measurement variables across the studies and the differences among the studies, a meta-analysis was not performed. A narrative assessment was performed for the outcomes: moisture/bleeding control, gingival displacement, gingival/periodontal health and the subjective outcomes.ResultsFrom the initial search that retrieved 1,342 articles, 19 potential relevant full-text articles were considered for the review. Seven studies were selected for the systematic review. Four randomised clinical trials were included. Sample size ranged from eight to 252 participants per study. Five studies were conducted on patients requiring any indirect fixed restorations on prepared teeth. Two studies were done on unprepared teeth. In all studies, participants were in good health, had a healthy gingival condition and a sound periodontal status.ConclusionsBoth techniques are reliable in achieving gingival retraction. The review supports the observation that gingival retraction paste can more effectively help to achieve a dry field and at the same time be less injurious to soft tissues, however its ability to displace gingival tissues, compared to retraction cord, was compromising. Rather than considering the cost of material or the individual preference of the operator, choosing the right technique to maximise clinical efficiency should be based on scientific evidence. It seems that impregnated gingival cords are more effective on thick gingival tissue whereas paste is more effective when minimal retraction is required for haemostasis control, preservation of the gingiva and less tissue displacement.
数据来源
在不同数据库中使用相似关键词进行了广泛的计算机检索，这些数据库包括：Ovid Medline、汤姆森ISI科学网、PubMed、Science Direct、EMBASE和考克兰图书馆。还检索了灰色文献、学位论文、摘要和专著。对所选文章的参考文献列表进行了手工检索。
研究选择
纳入标准包括使用带或不带排龈线的牙龈退缩技术的体内随机临床试验和半随机临床试验。如果研究考察了综述的主要结局：止血控制效率、牙龈移位量以及这些技术对牙龈/牙周健康的影响，则纳入该研究。该综述接受的次要结局包括患者报告的主观因素，如疼痛、敏感、异味和不适，以及术者对这两种技术的经验。排除非英文论文、临床报告、动物研究或体外研究。
数据提取与综合
两位作者独立检索和筛选文章。通过讨论解决分歧。第三位审阅者参与研究的合格性评估。使用考克兰协作工具评估偏倚风险。由于各研究中测量变量的异质性以及研究之间的差异，未进行荟萃分析。对结局进行了叙述性评估：湿度/出血控制、牙龈移位、牙龈/牙周健康以及主观结局。
结果
从最初检索到的1342篇文章中，有19篇潜在相关的全文文章被纳入综述。七项研究被选入系统评价。包括四项随机临床试验。每项研究的样本量从8名到252名参与者不等。五项研究针对需要对预备牙进行任何间接固定修复的患者开展。两项研究针对未预备牙进行。在所有研究中，参与者健康状况良好，牙龈状况健康，牙周状态良好。
结论
两种技术在实现牙龈退缩方面都是可靠的。该综述支持以下观察结果：牙龈退缩膏能更有效地帮助实现术区干燥，同时对软组织的损伤较小，然而与排龈线相比，其移位牙龈组织的能力较差。应基于科学证据选择合适的技术以最大化临床效率，而不是考虑材料成本或术者的个人偏好。似乎浸渍排龈线对厚牙龈组织更有效，而当需要最小程度的退缩以控制出血、保护牙龈和减少组织移位时，膏剂更有效。
