儿童牙科学课件：牙合生长发育-七年制

1、Outline牙的发育过程（复习）牙发育的时间牙萌出的时间和顺序*牙萌出的机制（自学）乳恒牙替换（自学）牙列与咬合发育*Development of Teeth PartAn important part of chewing organsThe characteristics of primary and permanent teeth (P22 43) morphology, number and functionThe rule of teeth development time, order and symmetryDevelopment and eruption of Teeth a

2、nd occlusion establishing OverviewDevelopment of teethTime for tooth development Sequence for tooth eruptionVariation in tooth eruption 1. Time for tooth developmentExperience three periods growth, calcification, eruption periods1933, Logan and Kronfeld studied calcification time of permanent tooth

3、In 1940, Macall and Schour offered a revised time table for permanent tooth development （ P53 tab 4-2 ） 1960, Nolla calcification of permanent tooth 1974，Lun and Law time table of primary teeth development （tab 4-3 ）釉质钙化完成，牙根发育，合方移动龈下或破龈，开始临床萌出根尖发育完成，萌出潜力减低牙胚存在：牙囊，钙化牙尖乳牙：胎儿4月；恒牙：出生evaluating teeth d

4、evelopment 10 stages of permanent tooth calcification（Nolla,1960）Tooth sitesBeginning of hard tissue formationEnamel formation completeeruptionRoots formation completeCentral incisor3-4 months4-5 years7-8 years10 yearsLateral incisor10-12 months4-5 years8-9 years11 yearscanine4-5 months6-7 years11-1

5、2 years13-15 yearsFirst premolar1.5-1.75 years5-6 years10-11 years12-13 yearsSecond premolar2-2.25 years6-7 years10-12 years12-14 yearsFirst molarborn2.5-3 years6-7 years9-10 yearsSecond molar2.5-3 years7-8 years12-13 years14-16 yearsThird molar7-9 years12-16 years17-21 years18-25 yearsTime table of

6、 permanent teeth development(Tab 4-2)maxillaryTooth sitesBeginning of hard tissue formation2Enamel formation complete6eruption8Roots formation complete10Central incisor3-4 months4-5 years6-7 years9 yearsLateral incisor3-4 months4-5 years7-8 years10 yearscanine4-5 months6-7 years9-10 years12-14 years

7、First premolar1.75-2 years5-6 years10-12 years12-13 yearsSecond premolar2.25-2.5 years6-7 years11-12 years13-14 yearsFirst molarBorn2.5-3 years6-7 years9-10 yearsSecond molar2.5-3 years7-8 years11-13 years14-15 yearsThird molar8-10 years12-16 years17-21 years18-25 yearsmandibularTime table of perman

8、ent teeth development (Tab 4-2)Tooth sitesBeginning of hard tissue formation(embryo age)Enamel formation complete (after born)eruption (after born)Roots formation complete (after born)Central incisor4 months1.5 months7.5 months1.5 yearsLateral incisor4.5 months2.5 months9 months2 yearscanine5 months

9、9 months18 months3.25 yearsFirst molar5 months6 months14 months2.5 yearsSecond molar6 months11 months24 months3 yearsmaxillaryTime table of primary teeth development (Tab 4-3)Tooth sitesBeginning of hard tissue formation(embryo age)Enamel formation complete (after born)eruption (after born)Roots for

10、mation complete (after born)Central incisor4 months2.5 months6 months1.5 yearsLateral incisor4.5 months3 months7 months1.5 yearscanine5 months9 months16 months3.25 yearsFirst molar5 months5.5 months12 months2.25 yearsSecond molar6 months10 months20 months3 yearsmandibularTime table of primary teeth

11、development (Tab 4-3)The early stage of the eruption Eruption period active and passive eruption The late stage of the eruption establishing occlusion: 23/35 yearsTeething Phenomenon bite, slobber, low thermal, food refusal, gingivitis Eruption periods of teeth2. Sequence of eruption12345671234567Th

12、e time and sequence of eruptionThe tooth eruption There is a certain time, order , symmetryThe lower was slightly earlier than that of the upperThe sequence of eruption(Tab 4-4,4-5) Be more clinically significant than the eruption timeThe sequence disorder often leads to malocclusion (occlusive guid

13、ance)sequencemandibularsequencemaxillary1Central incisor2Central incisor4Lateral incisor3Lateral incisor5First molar6First molar7Canine*8Canine*9Second molar10Second molarsequence of primary teeth eruption (Tab 4-4)第一乳磨牙先于尖牙萌出上颌侧切牙先于先下颌萌出sequenceMandibularsequencemaxillary1First molar2First molar3Ce

14、ntral incisor5Central incisor4Lateral incisor6Lateral incisor7Canine*8First premolar9First premolar10Second premolar11second premolar12Canine13Second molar14Second molarsequence of permanent teeth eruption(Tab4-5)上颌尖牙后于双尖牙萌出下颌四切牙先于上颌萌出3. Variation in tooth eruptionGenetic factors Sex, racialEnvironm

15、ental factors Nutrition, height, weight, region, diseaseLocal factors apical inflammationPosition: 34, 35Part II Space Management for Growing DentitionA 乳牙萌出前期无牙期C 乳牙咬合完成前期乳牙萌出期A 乳牙咬合完成期乳牙列期C 第一恒磨牙及前牙萌出开始期A 第一恒磨牙萌出完成期 （恒前牙部分或全部萌出完成）混合牙列期B 侧方牙群替换期C 第二恒磨牙萌出开始期A 第二恒磨牙萌出完成期C 第三恒磨牙萌出开始期A 第三恒磨牙萌出完成期A:Atta

16、ined(完成) C:Commenced(开始) B:Between A and CHellman咬合发育阶段分期恒牙列期( I ) Development of Dentition() Primary Dentition() Mixed Dentition() Primary DentitionPhysiological space in primary dentitionPrimary Dentition TerminusOcclusal relationship of the primary teethSize of the Primary Dental Arch1. Physiolog

17、ical space in primary dentitionPhysiological space - Primate space (灵长间隙) - Developmental space(发育间隙)Primate space(灵长间隙)Space between primary lateral incisor and primarycanine in maxilla in primate dentition Space between primary canine and first primary molarin mandible in primate dentition 34Y 56Y

18、with jaw developmentphysiological space presents in deciduous dentitionis called developmental spaceDevelopmental space(发育间隙)space typeincidence（%）space typeincidence（%）primate space 8.5both87.0developmental space0.5no space4.0Tab4-9 incidence of physiology space in primary dentition 2. Primary Dent

19、ition TerminusTerminal plane（第二乳磨牙末端平面） In primary occlusal position, the primary second molar distal relationship between jaws is called terminal planeVertical type垂直型Mesial type近中型Distal type远中型3. Occlusal relationship of the primary teethRelationship of the upper and lower teeth E E A ARelationsh

20、ip of the cusp and fossa C C D D DC CD ED DE overbite and overjet of primary anterior teethThe cross-angle of primary anterior tooth axis is larger than permanent ones，so the anterior relationship between jaws approximate to upright150o123oprimarypermanent4. Size of the Primary Dental ArchWidth of d

21、ental arch horizontal distance between the tip of primary canine and terminal of second primary molar Length of dental arch vertical distance from labial plane of primary incisor to primary canine and second primary molar.In deciduous dentition stage, the width of dental arch get larger， length of d

22、ental arch get smaller () Mixed DentitionPathway of eruption and occlusion establishment of first permanent molar The exchange of incisorslateral teeth group replacementeruption of second permanent molar 1. Pathway of eruption and occlusion establishment of first permanent molarDevelopment of the fi

23、rst permanent molar Eruption of the first permanent molar Occlusal relation of the first permanent molar 1.1 development of first permanent molarDental germ(牙胚) begined to form（embryo3-4M）Dental crown begined to calcify（birth）Dental crown calcification attained （2-3y）Tooth begined to erupt（6-7y）Dent

24、al root completed（9-10y）1.2 Eruption of first permanent molarPathway of eruption and occlusion establishment of first permanent molar1.3 Occlusal relation of first permanent molar Mesial type of terminal plane (14%) neutrocclusion relationVertical type of terminal plane(76%) Physiological space neut

25、rocclusion relation No physiological space Leeway space neutrocclusion relationsDistal type of terminal plane(10%) distal occlusion relations（majority） neutrocclusion relation（minority）2. The exchange of incisorsInter dental spaces in the primary incisor areaIncrease of inter canine widthIncrease of

26、 anterior length in the dental archchange of tooth axis of incisorsugly duckling stage2.2 Increase of inter canine widthdistance between tip of bilateral primary or permanent canine 2.3 Increase of anterior length in the dental archDental arch grow ahead Maxilla 1.4mm Mandible 0.1mmPermanent incisor

27、s labially shift: 23mm 2.4 change of tooth axis of incisors 150o123oDetal arch circumference increase 2.5 ugly duckling stageTemporary malocclussion (79%) Incisor erupt distalCenter space（正中间隙 ）Lower incisor crowding phenomenonMaxilla: (2-2)-(B-B)= 7mmMandible: (2-2)-(B-B)= 5mm3. lateral teeth group

28、 replacementLateral teeth group (canines, premolars)9Y begin to replace12Y replacement attainedLeeway spaceReplace sequence of lateral teethSpace analysis3.1 Leeway space(剩余间隙)The difference between the combined mesiodistal widths of the deciduous cuspids and molars and their successors - help to alleviate the incisor crowding adjust molar relationshi