Department of Prosthodontics, Faculdade Integrada de Pernambuco, Recife, Pernambuco, Brazil.
Department of Radiology, Latin American Institute for Dental Research and Education (ILAPEO), Curitiba, Paraná, Brazil.
Clin Oral Implants Res. 2017 Oct;28(10):1227-1233. doi: 10.1111/clr.12946. Epub 2016 Aug 2.
This randomized clinical trial analyzed crestal bone changes and soft tissue dimensions surrounding implants with an internal tapered connection placed in the mandible anterior region at different depths (equicrestal and subcrestal).
Eleven edentulous patients (five implants per patient) were randomly divided in a split-mouth design: G1, 28 equicrestal implants; and G2, 27 subcrestal implants. All implants were immediately loaded. Correlation between keratinized tissue width (KTW) and vertical mucosa thickness (MT) with soft tissue recession was analyzed. Intraoral radiographs were used to evaluate crestal bone changes. Patients were assessed immediately, 4-, and 8-months after implant placement. Rank-based ANOVA-type statistical test was used for comparison between groups (α = 0.05).
Fifty-five implants (G1 = 28 and G2 = 27) were assessed in 11 patients. Implant survival rate was 100% for both groups. Both tested implant placement depths presented similar crestal bone loss (P > 0.05). Significant crestal bone loss for each group was found in the different measurement times (T4 and T8) (P < 0.05). Implant placement depths, KTW, and vertical MT had no effect on soft tissue recession (P > 0.05).
Different implant placement depths do not influence crestal bone changes. Soft tissue behavior is not influenced by different implant placement depths or by the amount of keratinized tissue.
本随机临床试验分析了在下颌前牙区以不同深度（平齐嵴和骨下）植入具有内部锥形连接的种植体时的嵴顶骨变化和周围软组织的尺寸。
11 名无牙患者（每位患者 5 个种植体）被随机分为分牙设计：G1，28 个平齐嵴种植体；G2，27 个骨下种植体。所有种植体均立即加载。分析角化组织宽度（KTW）和垂直黏膜厚度（MT）与软组织退缩的相关性。使用口腔内射线照相评估嵴顶骨变化。在植入后立即、4 个月和 8 个月对患者进行评估。使用基于等级的 ANOVA 型统计检验比较两组（α=0.05）。
在 11 名患者中评估了 55 个种植体（G1=28 和 G2=27）。两组的种植体存活率均为 100%。两种测试的种植体植入深度呈现相似的嵴顶骨丧失（P>0.05）。在不同的测量时间（T4 和 T8），两组均发现明显的嵴顶骨丧失（P<0.05）。种植体植入深度、KTW 和垂直 MT 对软组织退缩没有影响（P>0.05）。
不同的种植体植入深度不会影响嵴顶骨变化。软组织的行为不受不同的种植体植入深度或角化组织量的影响。
