Abstract:

Objective: To evaluate peri-implant hard and soft tissues adaptation in the anterior maxillary sites (aesthetic zone) prepared with different implant shoulder orofacial positions. Methods: A randomized study in six healthy beagle dogs was carried out with bilateral first incisors(n=12) in the maxilla. They were divided into four groups, group A, early implant placement with a buccal bone width of 1 mm; group B, early implant placement with a buccal bone width of 2 mm; group C, immediate implant placement with a jumping gap width of 1 mm; group D, immediate implant placement with a jumping gap width of 2 mm. All groups underwent computer-guided surgery with concentrated growth factors (CGF) inserted into the jumping gap in immediate implant placement and no filling material or membrane was used in early implant placement groups. All implants were left to heal submerged for 3 months and the animals were sacrificed 1 month after flap surgery of gingivalplasty. The vertical bone resorption (VR), horizontal bone resorption (HR), buccal bone thickness (BT), keratinized mucosa width (KW), and bone-to-implant contact (BIC) of all groups were measured and compared. Results: Marked VR was observed more in group A than in group B, and in group C than in group D (P<0.05). The horizontal bone resorption (HR) was lower in group A than in group B, and in group C than in group D (P<0.05). Pronounced bone resorption occurred more in group A than in group B at the level of 1 mm apical to the implant shoulder(P<0.05). The bone-to-implant contact (BIC) of group C was higher than group A and D (P<0.05) and no difference was observed between group A and B (P>0.05). Comparing the width of keratinized mucosa (KW), at 4 months after implantation, group B was wider than group A(P<0.05) and during 3 months after implantation, group D was wider than group C(P<0.05). Conclusion: The implant shoulder placed 1 mm away from the labial bone crest lead to pronounced bone resorption and a decrease of keratinized mucosa width in the aesthetic zone. The implant shoulder placed 2 mm away from the labial bone crest effectively maintained the height of the labial bone wall and the width of the keratinized gingival in the aesthetic zone.

Key words: labial bone thickness, immediate implant placement, early implant placement, bone resorption, keratinized mucosa width

摘要：

目的：探讨前牙美学区植入种植体的颈部与唇侧骨板间距离对种植体周软硬组织的影响。方法：随机选取6只健康Beagle犬，在双侧上颌第一切牙处（共12个位点）行数字化外科导板辅助下的即刻种植和早期种植，并分为4组，A组（早期种植1 mm组），B组（早期种植2 mm组），C组（即刻种植1 mm组），D组（即刻种植2 mm组）。早期种植不使用任何植骨材料，即刻种植在跳跃间隙内置入浓缩生长因子（concentrated growth factor, CGF）。均采用埋入式缝合，3个月后翻瓣行牙龈成形术，术后1个月处死Beagle犬。比较各组唇侧牙槽嵴垂直骨吸收（vertical bone resorption, VR）、水平骨吸收（horizontal bone resorption, HR）、唇侧骨板厚度（bone thickness, BT）、角化龈宽度（keratinized mucosa width, KW）、种植体-骨结合率（bone-to-implant contact, BIC）。结果：垂直骨吸收数值比较，A组大于B组，C组大于D组（P<0.05）；水平骨吸收数值比较，A组小于B组，C组小于D组（P<0.05）。种植体颈部根方1 mm水平，A组的唇侧骨板吸收量大于B组。种植体-骨结合率比较，A组和B组间的差异无统计学意义（P>0.05），C组大于D组和A组（P<0.05）。角化龈宽度比较，种植术后3个月内，C组小于D组（P<0.05）；在种植术后4个月，A组小于B组（P<0.05）。结论：在前牙美学区，种植体颈部距离唇侧骨板1 mm时，种植体颈部发生明显骨吸收，角化龈宽度减少。在前牙美学区，种植体颈部距离唇侧骨板2 mm时，可以有效地维持唇侧牙槽嵴高度和角化龈宽度。

关键词: 唇侧骨板厚度, 即刻种植, 早期种植, 骨吸收, 角化龈宽度

CLC Number: 

• R782