Objective: To evaluate the clinical success of the treatment of maxillary anterior primary incisors caries with composite resin strip crowns.
Methods: Children who presented with severe early childhood caries and were treated comprehensive caries under general anesthesia from January to December 2016 were enrolled in this study. Composite crowns using preformed celluloid crown (3M ESPE, USA) called as "strip crown technique" were applied to treat vital primary incisors with two or multiple surface cavities. Selective etchings of enamel, Universal Bond adhesive and 3M Z350 resin were used to make strip crowns. The patients returned at the end of 6, 12 and 18 months and received clinical and radiologic examinations. Dentists who did not attend the treatment evaluated the strip crowns clinically by modified United States Public Health Service (USPHS) criteria.
Results: Four hundred eighteen restorations, placed in 127 children aged 1.17-5.75 years (average of 3.22), were evaluated. The overall retention rate was 97.8% at the end of 6 months, 93.6% at 12 months and 89.2% at 18 months. After 18 months, 28 restorations (6.7%) were totally lost and 4.1% were rated as having lost some resin material. Only four teeth (1.0%) had secondary caries at the end of 18 months and 1.4% teeth had pulpal pathology requiring root canal treatment. Composite crowns had good performance in contour and adjacent contact and improved aesthetics significantly. Twenty-nine teeth (6.9%) showed mild gingivitis and 93.1% showed healthy gingival. 11.2% of the teeth demonstrated color change because plaque accumulation and the polish could remove the stains. The complete loss of strip crowns was mainly related to eating bites.
Conclusion: Strip crowns performed well for restoring primary incisors with large or multisurface caries for periods of over 18 months. The strip crowns can be a durable and aesthetic restoration for vital carious primary incisors with adequate tooth structure after caries removal. Functional movement is an important cause of complete loss. Because of the high technical sensitivity and its requirement of the cooperation of children, strip crowns are more suitable for older and cooperative children as well as children receiving dental treatment under sedation or general anesthesia.
目的: 评价对活髓乳前牙复面洞和多面洞龋坏采用Strip crowns透明成形冠进行复合树脂全冠修复的临床效果。
方法: 纳入的研究对象为2016年1—12月接受全身麻醉下牙齿治疗，且因乳前牙复面洞或多面洞龋坏需行树脂全冠修复的患儿。术中使用选择性酸蚀技术、Universal Bond粘接剂、3M Z350树脂制作全冠。术后6、12和18个月复查，由非治疗医师采用改良的美国公共卫生署(United States Public Health Service，USPHS)标准进行单盲评价。
结果: 共有127例儿童的418颗牙齿纳入统计，年龄为1.17~5.75岁(平均3.22岁)，其中70例男性，57例女性。树脂冠6个月时的保留率为97.8%，12个月时的保留率为93.6%，18个月时的保留率为89.2%。18个月时共有28颗(6.7%)树脂冠完全脱落，17颗(4.1%)部分脱落，4颗(1.0%)树脂冠发生继发龋，6颗(1.4%)牙齿出现牙髓感染。修复体外观及邻接关系恢复较好，色泽协调性佳，可明显改善美观。93.1%的树脂冠牙龈健康，有29颗(6.9%)牙龈轻度红肿。有47颗(11.2%)树脂冠因菌斑堆积出现颜色变化，抛光可去除着色。树脂冠脱落主要与进食咬物相关。
结论: 树脂冠是修复乳前牙大面积龋坏和多面洞龋坏的较好方式，功能运动是导致脱落的重要原因。由于制作树脂冠技术敏感性高，需要儿童全程配合，更适用于年龄较大且可配合的儿童以及接受镇静或全身麻醉的儿童。
Keywords: Child; Dental caries; Primary incisors; Tooth crown.