1、授課章節牙齒發育異常授課對象口腔3系學時2時 間4014授課地點教 材葛立宏兒童口腔醫學 人民衛生出版社 教學目的要求掌握：牙齒萌出與脫落異常熟悉：牙齒結構、形態、數目異常教學重點難點重點: 牙齒結構、形態、數目異常，牙齒萌出與脫落異常難點；牙齒萌出與脫落異常 教學方法講授式啟發式教具多媒體課件授課提綱1、 牙齒結構異常 （40分）釉質發育不全、牙本質發育不全、氟牙癥、四環素牙先天性梅毒牙2、牙形態異常 （15分） 3、牙齒萌出過早、過遲、牙齒脫落異常 （20分） 4、牙齒數目不足、過多 （5分）教 學 主 要 內 容備 注 牙發育異常(developmental abnormality of

2、 teeth)主要內容 Summary牙結構異常 Abnormalities of histodifferentiation牙形態異常 Abnormalities of morphodifferentiation牙數目異常 Disturbances in number of teeth牙萌出異常 Disturbances in germination of teeth牙結構異常 Abnormalities of histodifferentiation釉質發育不全 enamel hypoplasia氟牙癥 dental fluorosis四環素牙 tetracycline stained te

3、eth遺傳性牙本質發育不全 hereditary dentinogenesis imperfecta先天性梅毒牙 congenital syphilitic teeth釉質發育不全 enamel hypoplasia定義 definition牙齒發育期間，由于全身疾患、營養障礙或乳牙的嚴重的根尖周感染所導致的釉質的結構異常。(enamel abnormalities of histodifferentiation result from systematic disease, nutrition deficiency or severe apical affection of deciduou

4、s dentition during teeth formation)病因 Aetiology營養障礙 nutrition deficiency內分泌失調 incretion disorder嬰兒、母體疾病 infant & maternal disease局部因素 localized causes嬰兒、母體疾病 infant & maternal disease出生前 Prenatal新生兒 Neonatal嬰兒 Postnatal出生前 Prenatal感染（infection)風疹(rubella)、梅毒(syphilis)母親的代謝性疾病（maternal system

5、ic disease)新生兒 Neonatal新生兒溶血性疾病（haemolytic disease of the newborn)低鈣血癥 （hypocalcaemia)早產兒/晚產兒（premature birth/prolonged labour)嬰兒 Postnatal感染尤其是重癥病毒感染（severe childhood infections especially the viral exanthemata)慢性疾病先天性心臟病、胃腸道疾病、內分泌疾病（chronic diseases in childhood,e.g. congenital heart disease, gast

6、rointestinal and endocrine diseases)營養不良維生素D缺乏（nutritional deficiency, e.g. vitamin D)腫瘤化療（cancer chemotherapy)氟中毒（excess fluoride ions)局部因素 localized causes感染（Infection)創傷 （Trauma)放療 (Radiotherapy)臨床表現 clinical features輕癥 mild type重癥 severe type輕癥 mild type釉質形態基本完整（smooth-surface enamel)僅有色澤和透明度的改變

7、 （white, opaque spots, brown-stained after eruption)重癥 severe type帶狀(橫溝狀)缺陷 (horizontal grooves in the enamel surface)窩狀缺陷 （pits in the enamel surface)釉質變薄 （general reduction in the thickness of the whole enamel)對稱發生 (symmetrical)提示 Note累及 631136 提示致病因素1歲以內 6321 1236（damage occur at age 1)累及2 2 提示致病

8、因素在出生后第2年（damage occur at age 2)累及754457 提示致病因素在23歲以后 754457 (damage occur at age 2-3)特納牙 Turner teeth乳牙的感染、創傷導致恒牙的造釉細胞的損傷（infection or trauma related to the deciduous predecessor resulting in damage to the ameloblasts of the permanent successor)釉質呈黃色或棕色（yellowish or brownish pigmentation of the ena

9、mel)表面凹陷、不規則(pits and irregularity of the surface) 牙冠小(the smaller crown than normal)治療 Therapy（略）氟牙癥Dental Fluorosis定義definition又稱氟斑牙或斑釉牙，主要是在牙齒發育礦化期，攝入過量的氟所引起的釉質發育不全、礦化不全。(ingestion of excessive fluoride during teeth formation result in enamel hypoplasia or hypocalcification)病因Aetiology攝入過量的氟離子（in

10、gestion of excess fluoride ions） 飲水含氟量，正常為1ppm（1 part per million of fluoride in the drinking water) 食物中的氟化物(fluoride in diet)損害釉質發育期牙胚的造釉細胞（damage ameloblasts during the tooth formation)造成釉質礦化不良，色素沉著（result in hypomineralized enamel & pigmentation)機理 Mechanism 磷酸酯（phospholipid)無機磷酸鹽（inorganic p

11、hosphate)機理 Mechanism在牙齒發育期間，過量攝入的氟才會導致氟牙癥（dental fluorosis result from a high intake during the period of tooth formation)氟不易通過胎盤屏障，乳牙一般不受累（Placenta barrier can resist fluoride, dental fluorosis seldom appear in deciduous dentition)提示：67歲以前，高氟攝入易患氟牙癥 ！ （Ingestion excess fluoride no more than 6-7 ag

12、e is prone to high prevalence)機理 Mechanism臨床表現 clinical features在同一時期萌出的釉質上有白堊色到褐色的斑塊(fluoride opacities occur symmetrically around the arch characterized by faint white flecking of the enamel, white patches or striations)嚴重者還并發釉質的實質缺損。(in severe cases may associate with loss of the normal tooth for

13、m)臨床上常按其輕、中、重度而分為白堊型（輕度)、著色型（中度）和缺損型（重度）3種類型。臨床表現 clinical features多見于恒牙，發生在乳牙者甚少，程度亦較輕。這是由于乳牙的發育分別在胚胎期和乳嬰期，而胎盤對氟有一定的屏障作用。因此，氟牙癥一般見于恒牙，但如氟攝人量過多，超過胎盤篩除功能的限度時，也能不規則地表現在乳牙上。(mainly found in the permanent dentition, but the deciduous teeth may be involved in severe cases and in areas of endemic fluorosi

14、s)對摩擦的耐受性差，但對酸蝕的抵抗力強。(high acid-resist, rapid loss by abrasion and attrition)嚴重的慢性氟中毒(severe cases)臨床表現 clinical features分類 Classification治療Therapy脫色（bleaching)復合樹脂（composite resin) （略）脫色（bleaching)四環素牙 tetracycline stained teeth 定義definition在牙齒的發育礦化期，服用的四環素族藥物，結合到牙組織內，造成的牙齒的染色(discoloration of teet

15、h resulting from deposits of tetracycline ingestion during tooth development)。病因 Aetiology在牙的發育礦化期（妊娠期和嬰幼兒8歲以下），服用的四環素族藥物，可被結合到牙組織內，使牙著色。(Tetracycline is administrated to pregnant females or to children under age of 8, it may be incorporated into the dentin of the developing teeth) 呈黃色，在陽光照射下則呈現明亮的黃

16、色熒光，以后逐漸由黃色變成棕褐色或深灰色。(It produces a yellow discoloration, the teeth will fluoresce from a bright yellow to brown to gray with exposure to light)四環素可通過胎盤引起乳牙著色。(Permeate placenta to affect deciduous dentition)病因 Aetiology臨床表現 clinical features著色（stain)可伴有釉質發育不全 (enamel hypoplasia)臨床表現 clinical featur

17、es治療Therapy復合樹脂修復法 (composite resin)外脫色法 (bleaching)內脫色法 (intracoronal bleaching)？復合樹脂修復法 (composite resin)外脫色法 (bleaching)外脫色法 (bleaching)比較 comparison遺傳性牙本質發育不全 hereditary dentinogenesis imperfecta 病因 Aetiology常染色體顯性遺傳(autosomal dominant)男、女患病率均等(equal frequency in males and females)乳、恒牙均可受累(affec

18、t both deciduous and permanent dentition) 病理（Pathology)釉質結構基本正常，釉牙本質界失去小弧形的排列而呈直線相交(normal enamel structure, but amelodentinal junction(ADJ) is straight rather than scalloped) 牙本質形成較紊亂，牙本質小管排列不規則(the dentine contains a reduced number of tubules, many of which are wide and irregular) 由于不斷較快地形成牙本質，髓腔消

19、失 (exhibit premature closure of the pulp chamber and canals)臨床表現 clinical features牙冠呈微黃色半透明，光照下呈現乳光(translucent, opalescent amber-like appearance)釉質易從牙本質表面分離脫落使牙本質暴露，從而發生嚴重的咀嚼磨損(enamel is rapidly lost and the teeth then show marked attrition)X線片可見牙根短。牙萌出后不久，髓室和根管完全閉鎖 (radiological examination shows

20、short , blunt roots with partial or even total obliteration of the pulp chambers and root canals by dentine)臨床表現 clinical features治療Therapy義齒修復先天性梅毒牙 congenital syphilitic teeth 病因 Aetiology梅毒螺旋體侵犯牙胚（infection of the tooth germ by treponema pallidum )臨床表現 clinical features半月形切牙 亦稱哈欽森牙(Hutchinson tee

21、th) 蕾狀磨牙 (Pfluger teeth，Moon teeth) 牙形態異常 Abnormalities of morphodifferentiation幾個疾病過大牙、過小牙、錐形牙融合牙、雙生牙、結合牙£畸形中央尖 牙內陷£釉珠融合牙(fused teeth)雙生牙(geminated teeth)結合牙(concrescence teeth)融合牙(fused teeth)定義：兩個正常的牙胚融合而成。(joining of two developing tooth germs)完全融合、不完全融合(completely or incompletely)雙生牙(

22、geminated teeth) 定義：一個內向凹陷將一個牙胚不完全分開而成。(one tooth attempts to split in two)完全、不完全分開的牙冠(two crowns or one large partially separated crown)一個共同的牙根(sharing a single root)結合牙(concrescence teeth) 定義：兩個牙根發育完成的牙齒發生粘連而成。借助牙骨質結合牙本質各自分開(the union of two adjacent teeth by excessive cementum production)畸形中央尖abn

23、ormal central cusp病因 Aetiology牙齒發育期，牙乳頭向造釉器突起 ，形成釉質和牙本質(enamel and dentine formation for dental papilla protruding into enamel organ during tooth formation)臨床表現 clinical features多見于下頜前磨牙以第二前磨牙最多見（5 5）合面中央窩半圓形突起中央尖折斷、磨損后，為圓形或橢圓形黑環，中央黑色小點（此處即使用極細的探針也不能探入）易造成牙髓感染、壞死，影響牙根尖的正常發育 喇叭形根尖臨床表現 clinical featur

24、es治療Therapy不作處理磨除脫敏(grind and desensitization)磨除備洞蓋髓治療(cavity preparation and pulp capping)根尖誘導成形術(apexification)牙內陷dens invaginatus 病因 Aetiology牙發育時期，成釉器過度卷疊或局部過度增殖，深人到牙乳頭中所致，牙萌出后，在牙面可出現一囊狀深陷的窩洞（deep surface invagination of the crown of tooth lined by enamel and dentine) 臨床表現clinical feature畸形舌側窩(lingual pit deformity)畸形舌側尖(accessory palatal cusp)畸形根面溝(root groove deformity)牙中牙(dens in dente)臨床表現clinical feature畸形舌側窩(lingual pit deformity) 易滯留菌斑、食物，造成牙髓病變(the defect cannot be kept free of plaque and bacteria