海量資源，盡在掌握
釉柱(enamel rod):為釉質(zhì)的基本結(jié)構(gòu),呈細(xì)長柱狀,貫穿釉質(zhì)全程,從釉牙本質(zhì)界放射狀伸向釉質(zhì)表面,其行走方向反映了成釉細(xì)胞形成釉質(zhì)時向后退縮的路線并非徑直。在窩溝處,釉質(zhì)從釉牙本質(zhì)界向窩溝底部集中呈放射狀;在牙頸部,釉柱幾...[繼續(xù)閱讀]
橫紋(cross striations):為釉柱上有規(guī)律間隔的細(xì)線,橫紋之間的距離約為 4μm,相當(dāng)于釉基質(zhì)每日形成的量。橫紋處礦化程度稍低,故當(dāng)牙輕度脫礦時橫紋較明顯。Cross striations:Enamel rods have regularly spaced cross striations and the distance between the ...[繼續(xù)閱讀]
絞釉 (gnarled enamel):釉柱自釉牙本質(zhì)界至牙表面的行程并不完全呈直線,近表面l/3較直,而內(nèi)2/3彎曲,在切緣及牙尖處絞繞彎曲更為明顯,稱為絞釉。絞釉可以增強(qiáng)釉質(zhì)對咬合力的抵抗。Gnarled enamel:The enamal rod from the EDJ the surface is not comp...[繼續(xù)閱讀]
釉質(zhì)生長線(incremental line):又稱芮氏線(line of Retzius),橫磨片中此線呈深褐色同心環(huán)狀排列,類似樹的年輪。縱磨片中,生長線自釉牙本質(zhì)界向外,在牙尖呈環(huán)形包繞牙尖,近牙頸部呈斜形線。釉質(zhì)生長線是釉質(zhì)周期性生長速率改變形成的間...[繼續(xù)閱讀]
釉梭(enamel spindle):釉梭是起始于釉牙本質(zhì)界伸向釉質(zhì)的紡錘狀結(jié)構(gòu),形成于釉質(zhì)發(fā)生的早期。此時牙本質(zhì)細(xì)胞的突起穿過基底膜伸向前成釉細(xì)胞之間。釉質(zhì)形成時此末端膨大的突起留在釉質(zhì)內(nèi)。在磨片中,牙尖和切緣部位較多見。Ena...[繼續(xù)閱讀]
釉板(enamel lamella):釉板是片狀、貫穿整個釉質(zhì)厚度的結(jié)構(gòu)缺陷,在磨片中觀察呈裂隙狀結(jié)構(gòu)。其鈣化程度低、窄而細(xì)長,數(shù)量比釉叢少,在釉質(zhì)橫斷面容易觀察到。Enamel lamella:Enamel lamella is a sheet-like structural defect that runs through the entire...[繼續(xù)閱讀]
釉牙本質(zhì)界(enamel dentinal junction, EDJ):代表來自于上皮和外間充質(zhì)兩種不同礦化組織的交界面,其外形呈連續(xù)的貝殼狀而不是一條直線。這種連接增大了釉質(zhì)和牙本質(zhì)的接觸面,有利于兩種組織牢固結(jié)合。Enamel dentinal junction:EDJ represents...[繼續(xù)閱讀]
無釉柱釉質(zhì)(rodless enamel):在近釉牙本質(zhì)界最先形成的釉質(zhì)和多數(shù)乳牙及恒牙表層,有 20～100μm厚的釉質(zhì)看不到釉柱結(jié)構(gòu)。近釉牙本質(zhì)界處的無釉柱釉質(zhì),是成釉細(xì)胞在最初分泌釉質(zhì)時 Tomes 突尚未形成所致,而外層則是成釉細(xì)胞分泌活動...[繼續(xù)閱讀]
牙本質(zhì)小管(dentinal tubule):為貫通牙本質(zhì)全層的管狀空間,充滿了組織液和一定量的成牙本質(zhì)細(xì)胞突起。牙本質(zhì)小管自牙髓表面向釉質(zhì)牙本質(zhì)界呈放射狀排列。Dentinal tubule:The dentinal tubule is a tubular space that penetrates the entire layer of denti...[繼續(xù)閱讀]
初級彎曲(primary curvature):牙本質(zhì)小管在牙尖部及根尖部的小管較直,而在牙頸部則彎曲呈“～”形,稱為初級彎曲,其近牙髓的一端較粗,越向表面越細(xì)且排列稀疏。Primary curvature:Dentinal tubules at the tip of the cusp and theapex are straight, while a...[繼續(xù)閱讀]
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