구치부 부분 결손 환자에서 즉시하중군과 지연하중군의 임상적 성공률을 측정하기 위한 전향적 연구가 계획되었다. 즉시하중군에서는 17명의 환자에 42개의 GSIII 임플란트(Osstem, Korea)를 식립하고 48시간 안에 하중을 가하였다. 대조군인 지연하중군에서는 15명의 환자에 27개의 GSIII 임플란트를 식립하고 평균 $2.6{pm}1.7$개월 후에 하중을 가하였다. 하중 전 1차안정성을 ISQ로 측정하였고 임상증상, 동요도, 연조직 반응을 식립 직후, 3개월 후, 6개월 후, 12개월 후에 평가하였다. 변연골 흡수량은 치근단 방사선 영상으로 측정하였고 Mann-Whitney test (${alpha}$=0.05)와 repeated measured ANOVA (${alpha}$=0.05)로 두 군의 차이를 검정하였다. 식립 직후 실험군과 대조군의 ISQ는 각각 $80.3{pm}7.1$과 $69{pm}17$이었다. 실험군은 95.23%의 성공률을, 대조군은 100% 성공률을 나타냈다. 3개월과 6개월 후 실험군의 변연골 흡수량은 대조군에 비해 유의성 있게 컸다(p<0.05). 하지만 12개월 후 두 군의 차이는 관찰되지 않았다 (p>0.05). 변연골 흡수량은 성별과 식립위치에 따른 차이가 없었다 (p>0.05). 실험의 한계 내에서, 1차안정성이 획득된다면 구치부 식립 GSIII 임플란트의 즉시하중은 예지성 있는 치료법이라고 여겨진다.
This prospective study was designed to compare clinical outcomes of immediately loaded implant with delayed loaded implant in partially posterior edentulous patients. For test group, 42 GS III (Osstem, Korea) implants in 17 patients were loaded within 48 hours after the placement. Control group was 27 implants in 15 patients loaded at $2.6{pm}1.7months$ from the placement surgery. Before loading, primary stability was evaluated by ISQ value. Clinical symptoms, mobility, soft tissue state was evaluated at baseline, 3 months, 6 months and 12 months of loading. Marginal bone level change was also measured with periapical radiographs. Mann-Whitney test (${alpha}$=0.05) and repeated measured ANOVA (${alpha}$=0.05) was used for marginal bone level change between two groups. At the baseline, mean ISQ value of test group and control group was $80.3{pm}7.1$ and $69{pm}17$ respectively. Test group showed 95.23% of success rate and 100% of control group was successful. At 3 and 6months of loading, significantly more bone resorption was observed in test group than in control group (p<0.05). However, there was no significant difference in the bone level change at 12months of loading between two groups (p>0.05). Marginal bone level change showed no significant difference with gender and location (p>0.05). Within the limitation of this study, when primary stability was obtained, immediate loading of GS III implant at posterior region could be predictable treatment option.
