성견에서 조기기능하중이 hydroxylapatite-coated IMZ 임플란트 주위 골형성에 미치는 영향

Abstract

[한글]

조기 기능적 하중이 임플란트 주위 골조직에 미치는 영향을 규명하기 위해 HA plasma spray coated IMZ임플란트를 성견의 하악 양쪽 소구치 부위에 이식하여, 6주에 기능을 하도록 한 것을 Ⅰ군, 9주에 기능을 하도록 한 것을 Ⅱ군, 12주에 기능을 하도록 한 것을 Ⅲ군, 그리고 16주 동안 기능을 하지 않은 것을 대조군으로 하여, 임플란트 주위 골조직을 황학 현미경, 형광 현미경, 편광 현미경 으로 관찰하고 형태계측학적 분석과 EPMA분석을 통해 다음과 같은 결론을 얻었다.

1. 임플란트를 이식한 대조군, 실험 Ⅰ군, 실험 Ⅱ군, 실험 Ⅲ군 모두 상피 조직의 하방 이주없이 골유착이 관찰되었고 일부에서는 골수조직과 접촉하고 있었다.

2. 임플란트 이식후 6주에 조기하중을 가한 실험 Ⅰ군은 하중을 가하지 않은 대조군에 비해 골형성 및 골개형이 빨리 일어났으나, 협측 변연부에서 골흡수 양상이 관찰되었다.

3. HA가 티타늄 금속으로부터 탈락되어 대식세포에 의한 HA의 탐식작용이 관찰되었다.

4. 임플란트와 골조직간의 계면에서 골접촉률 비교시 대조군, 실험 Ⅰ군, 실험 Ⅱ군, 실험 Ⅲ군 간에 유의차가 없었다.

5. EPMA를 이용한 임플란트 주위 골조직의 Calcium과 Phosphorous의 정량 분석에서 조기하중에 따른 비교시 대조군, 실험 Ⅰ군, 실험 Ⅱ군, 실험 Ⅲ군 간에 유의차가 없었다.

[영문]

The purpose of this study was to investigate the influence of early functional load on the bone formation around osseointegrated titanium implants. 15 HA plasma spray coated IMZ implants were placed into the previously extracted site of both

mandibular premolar areas of five adult dogs. The implants were divided into four groups : the control group was the implant without abutments during the experiment period : the experimental group Ⅰ was preloaded by connecting the contoured abutment after 6 weeks of healing : the experimental group Ⅱ was preloaded after 9 weeks of healing : the experimental group Ⅲ was loaded after 12 weeks of healing : and the mandibular first molar and surrounding tissues were selected for natural tooth group to compare the implant group. All dogs were injected intravenously

tetracycline, alizarin red S, and calcein for bone labeling. After the experimental period of 16 weeks, the dogs were sacrificed and longitudinal and horizontal sections of the bone-implant interface were cut and observed using light microscope, polarized microscope, fluorescence microscope, image analizer, and EPMA.

The results of this study were as follows :

1. All implant surfaces were well in contact with bone tissue, but some contact with bone marrow tissue was observed.

2. Bone formation and bone remodeling in the group Ⅰ pre-loaded after 6 weeks of healing appeared earlier than the control group without functional load, but marginal bone resorption of the buccal crestal bone was observed in the group Ⅰ.

3. HA particles separated from titanium body and phagocytosis of these partices by macrophages were observed.

4. The morphemetric analysis showed no significant differences in bone-implant contact rate among 4 groups.

5. EPMA analysis of calcium and phosphorous content showed no significant differences in the bone around implants among 4 groups.

The result of this study indicate the possibility of the early functional load to the implant using temporary prosthesis. The insufficient bonding strength in bone-to-implant interface and HA resorption by phagocytosis were observed regardless of functional load. Therefore, more research of HA coating method is required in future.