07 牙发育异常

非龋性疾病noncariousdisease牙外伤(injuryofteeth)牙发育异常(developmentalabnormalityofteeth)牙体慢性损伤（chronicinjuryofteeth)牙本质过敏症（dentinehypersensitivity)牙发育异常developmentalabnormalityofteeth主要内容Summary牙结构异常Abnormalitiesofhistodifferentiation牙形态异常Abnormalitiesofmorphodifferentiation牙数目异常Disturbancesinnumberofteeth牙萌出异常Disturbancesingerminationofteeth钟状期造釉器(enamelorganinbellstage)dentalpapillastellatereticulumenameldentineexternalenamelepithelium牙结构异常Abnormalitiesofhistodifferentiation釉质发育不全enamelhypoplasia氟牙症dentalfluorosis四环素牙tetracyclinestainedteeth遗传性牙本质发育不全hereditarydentinogenesisimperfecta先天性梅毒牙congenitalsyphiliticteeth釉质发育不全enamelhypoplasia定义definition牙齿发育期间，由于全身疾患、营养障碍或乳牙的严重的根尖周感染所导致的釉质的结构异常。(enamelabnormalitiesofhistodifferentiationresultfromsystematicdisease,nutritiondeficiencyorsevereapicalaffectionofdeciduousdentitionduringteethformation)釉质发育不良：釉质基质形成障碍(dyspoiesisofenamelmatrix)釉质矿化不良：基质形成正常，但矿化不良(hypomineralization)釉质实质缺损(withenamelloss)釉质无实质缺损(withoutenamelloss)enamelagenesisenamelhypocalcification病因Aetiology营养障碍nutritiondeficiency内分泌失调incretiondisorder婴儿、母体疾病infant&maternaldisease局部因素localizedcauses釉质发育不全（enamelhypoplasia)病因（Aetiology)婴儿、母体疾病infant&maternaldisease出生前Prenatal新生儿Neonatal婴儿Postnatal出生前Prenatal感染（infection)——风疹(rubella)、梅毒(syphilis)母亲的代谢性疾病（maternalsystemicdisease)新生儿Neonatal新生儿溶血性疾病（haemolyticdiseaseofthenewborn)低钙血症（hypocalcaemia)早产儿/晚产儿（prematurebirth/prolongedlabour)婴儿Postnatal感染——尤其是重症病毒感染（severechildhoodinfectionsespeciallytheviralexanthemata)慢性疾病——先天性心脏病、胃肠道疾病、内分泌疾病（chronicdiseasesinchildhood,e.g.congenitalheartdisease,gastrointestinalandendocrinediseases)营养不良——维生素D缺乏（nutritionaldeficiency,e.g.vitaminD)肿瘤化疗（cancerchemotherapy)氟中毒（excessfluorideions)局部因素localizedcauses感染（Infection)创伤（Trauma)放疗(Radiotherapy)临床表现clinicalfeatures轻症mildtype重症severetype轻症mildtype釉质形态基本完整（smooth-surfaceenamel)仅有色泽和透明度的改变（white,opaquespots,brown-stainedaftereruption)重症severetype带状(横沟状)缺陷(horizontalgroovesintheenamelsurface)窝状缺陷（pitsintheenamelsurface)釉质变薄（generalreductioninthethicknessofthewholeenamel)特点：对称发生(symmetrical)例外？（exception)对称发生(symmetrical)提示Note累及631136提示致病因素1岁以内63211236（damageoccuratage1)累及22提示致病因素在出生后第2年（damageoccuratage2)累及754457提示致病因素在2－3岁以后754457(damageoccuratage2-3)特纳牙Turnerteeth乳牙的感染、创伤导致恒牙的造釉细胞的损伤（infectionortraumarelatedtothedeciduouspredecessorresultingindamagetotheameloblastsofthepermanentsuccessor)釉质呈黄色或棕色（yellowishorbrownishpigmentationoftheenamel)表面凹陷、不规则(pitsandirregularityofthesurface)牙冠小(thesmallercrownthannormal)治疗Therapy（略）氟牙症DentalFluorosis定义definition又称氟斑牙或斑釉牙，主要是在牙齿发育矿化期，摄入过量的氟所引起的釉质发育不全、矿化不全。(ingestionofexcessivefluorideduringteethformationresultinenamelhypoplasiaorhypocalcification)病因Aetiology摄入过量的氟离子（ingestionofexcessfluorideions）饮水含氟量，正常为1ppm（1partpermillionoffluorideinthedrinkingwater)食物中的氟化物(fluorideindiet)损害釉质发育期牙胚的造釉细胞（damageameloblastsduringthetoothformation)造成釉质矿化不良，色素沉着（resultinhypomineralizedenamel&pigmentation)机理Mechanism磷酸酯（phospholipid)——无机磷酸盐（inorganicphosphate)碱性磷酸酶（Alkaliphosphatase）抑制(inhibition)骨、牙齿的重要组成部分焦磷酸和ATP——骨基质矿化(mineralization)氟浓度增高（fluorideincreasing)结果（result)：釉质矿化不良（hypomineralizedenamel)造釉细胞（ameloblast)高氟导致氟牙症（excessfluorideresultindentalfluorosis)？(pyrophosphoricacidandAdenosineTriphosphate)机理Mechanism在牙齿发育期间，过量摄入的氟才会导致氟牙症（dentalfluorosisresultfromahighintakeduringtheperiodoftoothformation)氟不易通过胎盘屏障，乳牙一般不受累（Placentabarriercanresistfluoride,dentalfluorosisseldomappearindeciduousdentition)提示：6－7岁以前，高氟摄入易患氟牙症！（Ingestionexcessfluoridenomorethan6-7ageispronetohighprevalence)机理Mechanism氟牙症（dentalfluorosis)临床表现clinicalfeatures在同一时期萌出的釉质上有白垩色到褐色的斑块(fluorideopacitiesoccursymmetricallyaroundthearchcharacterizedbyfaintwhitefleckingoftheenamel,whitepatchesorstriations)严重者还并发釉质的实质缺损。(inseverecasesmayassociatewithlossofthenormaltoothform)临床上常按其轻、中、重度而分为白垩型（轻度)、着色型（中度）和缺损型（重度）3种类型。临床表现clinicalfeatures多见于恒牙，发生在乳牙者甚少，程度亦较轻。这是由于乳牙的发育分别在胚胎期和乳婴期，而胎盘对氟有一定的屏障作用。因此，氟牙症一般见于恒牙，但如氟摄人量过多，超过胎盘筛除功能的限度时，也能不规则地表现在乳牙上。(mainlyfoundinthepermanentdentition,butthedeciduousteethmaybeinvolvedinseverecasesandinareasofendemicfluorosis)对摩擦的耐受性差，但对酸蚀的抵抗力强。(highacid-resist,rapidlossbyabrasionandattrition)严重的慢性氟中毒(severecases)临床表现clinicalfeatures分类Classification级别临床特征正常釉质呈乳白色、半透明、有光泽可疑能见到数个白色斑点极轻有白垩色条纹或不规则散布的小面积不透明区，整个面积不超过牙面的1/4轻度白垩色区域扩大，整个面积不超过牙面的1/2中度牙形态无变化，上述所见常累及整个牙面，伴有广泛着色，呈茶褐色重度釉质有严重的发育不全，常有表面形态的改变并伴有广泛着色，颜色自棕色至灰黑色不等治疗Therapy脱色（bleaching)复合树脂（compositeresin)（略）脱色（bleaching)四环素牙tetracyclinestainedteeth定义definition在牙齿的发育矿化期，服用的四环素族药物，结合到牙组织内，造成的牙齿的染色(discolorationofteethresultingfromdepositsoftetracyclineingestionduringtoothdevelopment)。病因Aetiology在牙的发育矿化期（妊娠期和婴幼儿8岁以下），服用的四环素族药物，可被结合到牙组织内，使牙着色。(Tetracyclineisadministratedtopregnantfemalesortochildrenunderageof8,itmaybeincorporatedintothedentinofthedevelopingteeth)呈黄色，在阳光照射下则呈现明亮的黄色荧光，以后逐渐由黄色变成棕褐色或深灰色。(Itproducesayellowdiscoloration,theteethwillfluorescefromabrightyellowtobrowntograywithexposuretolight)四环素可通过胎盘引起乳牙着色。(Permeateplacentatoaffectdeciduousdentition)病因Aetiology四环素（tetracycline)四环素牙（tetracyclinestainedteeth)恒牙（permanentdentit