6週間にわたる下顎と上顎の歯槽骨形成の比較：X線学的検討

A comparison of mandibular and maxillary alveolar osteogenesis over six weeks: a radiological examination.

抄録

はじめに:

上顎と下顎の歯槽骨に同様の欠損を形成し、その再生率や骨密度のX線学的差異を比較する情報は十分ではない。

INTRODUCTION: Insufficient information exists on comparing radiological differences in bone density of the regeneration rate in the alveolar bone of the maxilla and mandible following the creation of similar defects in both.

方法:

5頭の健康なチャクマヒヒから歯槽骨欠損を作成した。標準化したX線画像を経時的に取得し、選択した欠損部位の密度を術前、術後直後、術後3週後および6週後に測定した。密度の差はANOVAを用いて統計的に検定した。

METHODS: Alveolar bone defects were created from five healthy Chacma baboons. Standardized x-ray images were acquired over time and the densities of the selected defect areas were measured pre-operatively, directly post-operatively and at three- and six weeks post-operatively. Differences in densities were statistically tested using ANOVA.

結果:

上顎は下顎に比べ、X線学的に有意に密度が高かった（p=0.026）。上顎と下顎では、それぞれ術後直接、術後3週間と6週間の間に差は得られなかった。すなわち、欠損が形成された後の各時点で密度に有意差は認められなかった（3週間：t=1.08、p=0.30、6週間：t=1.35、p=0.19、3～6週間：t=1.20、p=0.25）。下顎の密度増加は、3週間で106％（8.9±7.6％/回、4.3±2.7％/回）、6週間で28％（15.0±8.1％/回、11.7±8.0％/回）、3～6週間では56％（12.5±9.7％/回 対 8.0±6.9％/回）であり、同じ間隔で上顎よりも高かった。

RESULTS: The maxilla was significantly more radiologically dense (p = 0.026) than the mandible pre- operatively. No differences were obtained between the maxilla and mandible directly postoperatively and three- and six weeks post-operatively respectively; i.e. densities were not significantly different at the different time points after the defects had been created (three weeks: t = 1.08, p = 0.30; six weeks: t = 1.35, p = 0.19; three to six weeks: t = 1.20, p =0.25). The increase in density in the mandible was 106% (8.9 ± 7.6%/time versus 4.3 ± 2.7%/time) over three weeks, 28% (15.0 ± 8.1%/time versus 11.7 ± 8.0%/time) over six weeks and 56% (12.5 ± 9.7%/time versus 8.0 ± 6.9%/time) over three-to-six weeks and was higher than in the maxilla over the same intervals.

結論:

標準化されたグレースケール解析による放射線学的検査は、上顎と下顎の骨密度の差を決定するのに使用できる。統計学的に有意ではなかったが、下顎骨の治癒速度は上顎骨よりも速く、特に欠損を形成してから最初の3週間に観察された。

CONCLUSIONS: Radiological examination with its standardized gray-scale analysis can be used to determine the difference in bone density of the maxilla and mandible. Although not statistically significant, the mandible healed at a faster rate than the maxilla, especially observed during the first three weeks after the defects were created.