Department of Oral and Maxillofacial Surgery, Universidade Federal de Uberlandia, Uberlândia, MG, Brazil.
Int J Oral Maxillofac Implants. 2013 May-Jun;28(3):e128-34. doi: 10.11607/jomi.2885.
To demonstrate the degree of stability decrease and subsequent increase of dental implants at early implantation times in a beagle model.
The mandibular premolars and first molars of eight beagle dogs were extracted and the ridges allowed to heal for 8 weeks. Thirty-two (n = 16 each group) implants were placed bilaterally, and remained in vivo for 1 and 3 weeks. The implants with comparable dimensions were divided as follows: group 1, Straumann Bone Level with SLActive surface; group 2, Nobel Speedy Replace RP with TiUnite surface. During insertion and following sacrifice, the implants were torqued to determine insertion and interface failure values. Histologic sections were prepared for microscopy. Statistical analysis was performed using Kruskal-Wallis and multiple paired and non-paired t tests considering unequal variances at a 95% level of significance.
High insertion torque values were observed along with a significant decrease at 1 week in vivo (P = .003). At 3 weeks, the biomechanical fixation levels increased and were comparable to the insertion torque value. Histology showed that interfacial bone remodeling and initial woven bone formation was observed around both implant groups at 1 and 3 weeks.
As time elapsed early after implantation, the biomechanical stability of dental implants initially decreased and subsequently increased.
在比格犬模型中，展示早期种植体植入时种植体稳定性降低和随后增加的程度。
八只比格犬的下颌前磨牙和第一磨牙被拔出，牙槽嵴愈合 8 周。每侧植入 32 个（n=16 个/组）种植体，植入体在体内保留 1 周和 3 周。具有相似尺寸的种植体分为以下两组：组 1，Straumann 骨水平 SLActive 表面；组 2，Nobel Speedy Replace RP TiUnite 表面。在插入和后续牺牲过程中，将种植体扭转以确定插入和界面失效值。制备组织学切片进行显微镜检查。使用 Kruskal-Wallis 检验和多个配对和非配对 t 检验，考虑到 95%置信水平下的方差不等，对统计数据进行分析。
观察到高插入扭矩值，并且在体内 1 周时显著降低（P=0.003）。在 3 周时，生物力学固定水平增加，并与插入扭矩值相当。组织学显示，在 1 周和 3 周时，两组种植体周围都观察到界面骨重塑和初始编织骨形成。
随着植入后时间的推移，种植体的生物力学稳定性最初降低，随后增加。
