The purpose of this study was to evaluate the biological characteristic of deproteinized freeze dried bovine bone(DFDBB) through grafting to maxillary sinus as following time lapsed. Nine patients who were needed of sinus elevation procedure because of severe resorption of maxillary edentulous alveolar bone were selected. patients were divided into three group. Firstly sinus lifting procedure was performed and then the implantation procedure was performed after 6 months in first group, 12 months in second group and 18 months in third group and simutaneously tissues of sinus were obtained by trephine. 18 sections are made from every obtained tissue. 9 sections were stained by Masson's trichrome method and were taken a photo at 100 times of magnification. Relative area of newly formed bone were obtained by IPTK(image processing tool kit) version 5.0 program and mean values and standard deviations were produced from obtained data by using SPSS version 17 program and significance tests were conducted by ANOVA method. This study revealed that DFDBB stimulated new bone formation in maxillary sinus and did not have osteoinductive capacity but osteoconductive capacity, and DFDBB was exceedingly slowly resorbed.

I. 서론
 II. 재료 및 방법
  1. 환자의 선택
  2. 외과적 술식 및 조직편의 채취
  3. 조직절편의 준비
  4. 결과의 통계적 분석
 III. 결과
  A. 조직학적 결과
  B. 조직계측학적 결과
 IV. 토론
 V. 결론.
 VI. 참고문헌

• 박경주(단국대학교 치과대학 구강병리학교실) | Gyeong Ju Park correspondence