夜間義歯撤去が咬合圧による義歯床下組織の病理組織学的変化に及ぼす影響

夜间拔牙对咬合压力引起的义齿基托组织病理学变化的影响

• 批准号: 05771683
• 负责人: 永禮 五明
• 金额: $ 0.58万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Encouragement of Young Scientists (A)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05771683/
• 关键词: 義歯床下組織; 義歯の夜間撤去; 咬合圧; 骨動態; 組織計測

15週齡のWistar系雄性ラット50匹の口蓋に咬合時に規定量だけ沈下して義歯床下組織に2.0gf/mm^2の咬合圧を伝達する義歯床を装着した.実験動物の半数の25匹は昼間のみ,残り半数は昼夜を通じて義歯床を装着することによって,夜間義歯撤去が咬合圧による義歯床下組織の変化に及ぼす影響に関して検討を加えた.義歯床装着の2,4,7,10および14日後に口蓋組織を採取し,頬舌的な4mumのパラフィン切片としてhematoxylineosin染色を施した.得られた標本を用いて病理組織学的観察を行うとともに,二次元画像解析装置を用いて,骨組織の吸収に関する組織計測,統計処理を行い骨組織の吸収動態を観察した.その結果,下記の知見を得た.1.昼夜義歯床装着群:義歯床装着4日後から上皮基底細胞の配列の乱れと,粘膜固有層の圧扁がわずかに認められた.7日後には,4日後にみられた義歯床下粘膜組織の退行性変化の進行に加えて,義歯床下骨組織の吸収の開始が観察され,分画吸収面率は20.7%,活性吸収面率は92.9%であった.10日後には義歯床下組織の退行性変化は7日後に比べて進行し,骨組織では著名な吸収が認められ,分画吸収面率は70.1%,活性吸収面率は79.4%,平均破骨細胞数は19.8個/mm,相対破骨細細胞数は35.7個/mmであった.14日後には,義歯床下組織の退行性変化は10日後に比べてさらに増強したが,骨組織の吸収は10日後に比べて減少傾向を示し,その分画吸収面率は55.0%,活性吸収面率は64.7%,平均破骨細胞数は9.3個/mmであった.2.夜間義歯撤去群:観察期間を通じて義歯床下組織には病理組織学的変化は認められなかった.以上のことから,夜間に義歯を撤去することは,義歯床下組織に惹起される組織変化を回復,予防することによって,義歯床下の粘膜組織ならびに骨組織の保全に対して有効であることが示唆された.

A 15-week-old male Wistar was fitted with a 2.0 gf/mm^2 occlusal pressure of 2.0 gf/mm^2 in the submandibular tissue at the required amount of occlusal pressure. Half of the animals were exposed to light during the day, and the remaining half were exposed to light during the day and night. After 2, 4, 7, 10, and 14 days, the flap tissues were taken, and the 4 mum sections of the cheek and tongue were stained with hematoxylineosin. In order to obtain the results of pathological observation, the two-dimensional image analysis device was used to measure and statistically process the absorption dynamics of bone tissue. The results of this study are summarized below. 1. Day and night dental bed installation group: 4 days after implantation, the epithelial basal cell alignment disorder and the pressure of lamina propria were observed. 7 days later, 4 days later, the degeneration of the subgingival mucosa was observed, and the absorption of subgingival bone tissue was observed. 10 days later, the degeneration of the tissue under the bone bed was more progressive than 7 days later, and the bone tissue was more obvious than 7 days later. The absorption rate of the bone tissue was 70.1%. The active absorption rate was 79.4%, the average number of osteoclasts was 19.8/mm, and the corresponding number of osteoclasts was 35.7/mm. After 14 days, the degeneration of the tissue under the dental bed was stronger than that after 10 days. The absorption rate of bone tissue decreased after 10 days, and the absorption rate of bone tissue was 55.0%, the active absorption rate was 64.7%, and the average number of osteoclasts was 9.3/mm. During the observation period, the tissue under the microscope was examined by pathological examination. In the evening, the tissue under the dental bed was removed, and the tissue under the dental bed was restored to prevent the mucosal tissue under the dental bed from being preserved.