Histologic findings of three-wall intrabony defects around dental implants using different grafting materials in beagle dogs

Abstract

[한글]

연구목적: SLA surface dental implant 주위의 3면 골내낭에서 xenogeneic demineralized bone matrix putty, porous β-tri-calcium phosphate, 새로이 개발된 non-crystalline calcium phosphate glass를 사용한 치료를 조직학적으로 비교 평가하기 위한 것이다. 연구방법: 실험동물로는 15개월에서 18개월 사이의 12kg에서 15kg 정도되는 성견을 사용하였다. 20개의 SLA surface implant가 사용되었으며, 성견 하악의 양측에 각각 2개씩 사용되었다. 임플란트 식립전에, 각각의 임플란트 근심면에 straight fissure bur를 이용하여 표준화된 3면 골내낭 (근원심 5mm×협설 3mm×깊이 3mm)을 형성하였다. 형성된 골 결손부에는 demineralized bone matrix putty, porous β-tri-calcium phosphate, non- crystalline calcium phosphate glass를 넣은 것을 각각 실험군으로, 이식재를 넣지 않은 것을 대조군으로 사용하였다. 8주 후에 실험 동물을 희생시키고 조직학적 관찰을 하였다. 결과: 조직학적 소견상 임플란트 주위에 급성 염증 소견은 보이지 않았으며, non-crystalline calcium phosphate glass은 매우 적은량의 신생골을, β-TCP을 이용한 골내낭에서는 약간의 기저부에서 유래된 신생골이 관찰된다. β-TCP granules 가운데로 상당량의 측면의 골에서 유래된 신생골 형성이 보인다. xenogeneic DBM putty에서는 적은 량의 신생골이 기저부에 형성된 것을 볼수 있으며 대조군과의 차이는 크지 않다. 이식재의 종류와 상관없이 흡수되지 않은 이식재를 임플란트 주위에서 관찰할 수 있었다. 골내낭 안의 이식재들은 모두 connective tissue로 둘러 싸여 있었다. 모든 실험군에서 이식재에서 기인한 신생골 형성과 임플란트 표면에 신생 골유착의 조직학적 증거는 발견되지 않았다.

[영문]

Background: The Purpose of this study was to histologically evaluate and compare the healing of the three-wall defects using xenogeneic demineralized bone matrix putty (xDBM putty), porous β-tri-calcium phosphate (βTCP), newly developed non-crystalline calcium phosphate glass around submerged SLA(Sand blasted with Large-grit and Acid Etched) surface dental implant. Methods: Five male, lab-bred Beagle dogs were used in this study. At the beginning, these animals were approximately 15-18 months old and weighed between 12㎏ and 15㎏. Twenty SLA surface dental implants were placed bilaterally, two implants on each side of the mandible. Before placement, a standardized 3-wall intrabony defect (3mm buccolingual×3mm apicocoronal×5mm mesiodistal) was created at the mesial of the each implant site with a straight fissure bur. Defects were then grafted with either xDBM putty, β-tri-calcium phosphate, non-crystalline calcium phosphate glass or not filled (control). Experimental animals were sacrificed at 8 weeks later. Results: There was no evidence of acute inflammatory reaction around any of the implants. Result from this limited study demonstrated that intrabony defects around implants treated with non-crystalline calcium phosphate glass showed minimal amount of new bone formation. There were significant extent of new bone formation from the base of the bone in xenogeneic DBM putty and β-TCP. However, the amount of new bone formation in xenogeneic DBM putty and β-TCP showed no significant difference in related with control defects. Most of residual graft particles adjacent to the implant, embeded in connective tissue, were observed from all specimens regardless of graft type. Although bone fill was observed clinically, our histologic sections demonstrated regenerated tissue with fibrous consistency. There was a little amount of newly formed bone among the β-TCP granules. Ingrowth of new bone from lateral wall was observed in β-TCP specimen. But, all the treatment groups in this study showed no histologic evidence of new bone formation and bone to implant contact originating from grafted materials.