《犬猫牙科学》PPT课件.ppt

1、犬 猫 牙 科 学,中国农业大学兽医硕士 宋 军,齿列,Teeth description: 门齿Incisors 犬齿Canines 前臼齿Premolars 臼齿Molars 乳齿Deciduous teeth,primitive carnivores I 3/3 C 1/1 P4/4 M3/3 = 44 Saber tooth cat: I 3/3 C1/1 P2/1 M1/1 = 26 现代肉食动物，尤其是猫科，齿数减少 犬：I3/3 C1/1 P4/4 M2/3 =42 猫：I3/3 C1/1 P3/2 M1/1 =30 兔：I2/1 C0/0 P3/2 M3/3 =28 大鼠：I1

2、/1 C0/0 P0/0 M3/3 =16,位置的名称,牙的上下部：(Crown, Neck, Root) coronal: 向牙冠的方向 apical: 向牙根的尖端 牙内侧及外侧： buccal/labial/facial: 向唇或面颊的一侧(外侧)。 lingual/palatal：向舌或硬颚的一侧(内侧)。 牙的前后侧： interproximal: 两颗牙之间。 mesial：向第一门齿侧(前侧)。 distal ：远离第一门齿侧(后侧,Enamel Hardest, most mineralized tissue in the body Enamel of dog and cat

3、is much thinner than that in man Dentin harder than bone, softer than enamel produced by odontoblasts , tubular structure primary dentin 形成牙的外形 secondary dentin 成年后渐使pulp口径变小 exposed dentin very sensitive Dentin刚expose时很痛，但是一段时间之后，会sclerosis，就不会痛了,Pulp Very vascular and containing nerve fibers apica

4、l delta: 在apex形成许多渠道，称为apical delta，由神经及血管淋巴通过。人的apex通常只有一个foramen,牙周膜Periodontium,外侧(buccal)的主要软组织： 口腔粘膜Oral mucosa (未角化) Buccal mucosa Alveolar mucosa Mucogingival line,牙周膜Periodontium,齿龈Gingiva Attached gingiva (角化) Free gingiva：正常的free gingiva成刀状紧紧贴着牙齿。 Free gingiva 与牙齿间形成的沟称为Gingiva sulcus (龈沟)

5、，在健康的动物约0.5-2mm深。龈沟的上皮未角化。龈沟中常有分泌的neutrophils及液体形成防御机构,牙周膜Periodontium,牙齿的固着： 在attached gingiva部份是靠gingival fiber bundles (拔牙时要以刀片先切断此区，以免连部份gingiva一起拉出来)。 在alveolar bone上是靠periodontal ligament，这个ligament是连接在牙根表面的齿垩质(cementum)及alveolar bone 。ligament中有神经，让动物知道调整咬合力,胚胎学,bug stagecap stagebell stage 如

6、果在胚胎期未形成tooth bug，就不会形成永久齿。 犬的牙齿先形成dentin，再形成enamel，最后形成牙根区，在此之前apex区是开放的，所以此时很脆弱,Development and congenital缺陷,中国冠毛犬就因为epithelium发育不全而无毛，牙齿也是同一来源，所以也会不正常或缺齿。 双排牙：要尽快把乳牙拔掉，才能有正确的齿列及咬合，但要小心不要破坏永久齿的下方,Development and congenital缺陷,enamel hypoplasia: 人：measles，犬：canine distemper 也有可能是其他在胚胎时期破坏牙组织的事件：e.g.

7、: abscess, TC, etc,Periodontology,Plaque牙菌斑：a mixed film of bacteria in a matrix formed by salivary glycoprotein and sulcular fluid,Periodontology,Calculus齿石：(不用”tartar”,Calculus齿石：(不用”tartar”) 形成： Supragingival mineral source: saliva Subgingival mineral source: gingival fluid Food debris and hair a

8、re often found in calculus as well. 重要性：calculus itself is not a pathogenic agent, and its roughness does not cause gingivitis. But it keeps plaque in close contact with the gingiva and prevents plaque removal,Periodontal disease,牙周病为由牙菌斑所引起的炎症性疾病，刚开始时只影响到齿龈(gingiva)，称为齿龈炎(gingivitis)。 分级(Holmstrom,

9、 Frost & Gammon, 1992) 0: normal 1: Gingivitis, mild 2: Gingivitis, moderate, supragingival calculus 3: Periodontitis, subgingival calculus, pocket formation 4: Periodontitis, severe, deep pocket, bone loss, mobility,Periodontal diseaseGingivitis齿龈炎,reversible 早期: gingival sulcus细菌增加。通常无临床症状。 正常状况下为

10、G+菌及及少量G-菌 当这些细菌增加耗氧后，G-菌及厌氧菌增加，就会形成gingivitis。 目前是认为某些特殊的细菌，而不是总细菌量，会造成gingivitis。在人类与猫的的各型gingivitis都与不同的细菌有关,Periodontal diseaseGingivitis齿龈炎,细菌继续增加，其他炎症细胞参与，细菌及PMN分泌collagenase，此时因为微血管增生，所以不但局部会发红，并且探查时会流血。 慢性的gingivitis：血管淤积、静脉回流受阻，造成牙龈呈蓝色或深红的外观,Periodontal diseasePeridontitis牙周炎,peridontitis由g

11、ingivitis恶化造成。为irreversible。 pocket formation and gingival recession destruction of ligament resorption of alveolar bone,Periodontal diseasePeridontitis牙周炎,gingival sulcus因为junctional epithelium的collagen流失而变深，称为periodontal pocket。 pocket / sulcus超过4 mm牙刷就刷不到了。 当probing depth变深，要辨认是因为true attachment

12、loss (sulcus变深)，或gingival hyperplasia (gingiva 长高)。当probing depth 正常或变短，也可能是存在attachment loss但同时有gingival recession,Periodontal diseasePeridontitis牙周炎,一但pocket形成，要去除牙菌斑就非常困难，软组织的炎症最后就导至骨吸收(bone resorption) horizontal bone loss：alveolar bone减少高度，但仍与cemento-enamel junctions平行。最常见。 vertical bone loss：垂

13、直损失骨。多牙根的牙形成叉状(furcation,Periodontal disease牙周病的危险因子,不平滑的表面或躲藏plaque的地方 (calculus, exposed furcation) decreased saliva: panting or other clinical problem nutritional : vit B-complex ,Vit D and Ca, P ,Protein systemic diseases : DM, leukemia, anemia ,hyperparathyroidism, etc,Routine periodontal treat

14、ment,例行预防性质 complete regeneration 只有在单纯gingivitis，没有attachment loss时才可能发生。 healing of pockets：形成long junctional epithelium, minimal CT regeneration , cessation of attachment loss Elimination of active inflammation,Routine periodontal treatmentBefore you start,Access general health of the patient: 因为

15、periodontitis有许多是全身性的原因。 Mucosal bleeding time: screening blood coagulation disorder。 高度建议使用气麻： cuffed endotracheal tube is mandatory for dental procedures duration of procedure is often unpredictable,Routine periodontal treatmentBefore you start,Antibiotics: Periodontal treatment and tooth extracti

16、on causes a considerable bacteremia 如没有特殊理由(另一次麻醉更危险，或同时进行的手术是小手术)，最好不要将periodontal treatment与其他的手术合并施行。 usually the bacteremia associated with periodontal treatment will clear up after 20 min,Routine periodontal treatmentBefore you start,通常只在下列情况下需要预防性抗生素(prophylaxis antibiotics)，即手术前五天开始的抗生素(Augme

17、ntin 20mg/kg PO，用较低剂量因为希望保留口腔flora)： 年老衰弱病患 pre-existing heart disease periodontal treatment combined with elective surgery 重大拔牙过程 preexisting gross infection or stomatitis,Routine periodontal treatmentBefore you start,使用抗生素的原则仍有争议： 最常用：IV wide spectrum antibiotics (ampicillin 20mg/kg IV) at premed

18、or induction metronidazole in severe cases Antiseptics: Flush with Chlorhexidine gluconate (猫0.05%，狗可用高一点)prior to and during periodontal treatment. 有的洗牙机可以用以上溶液替代水,Routine periodontal treatment,病患体位： Lateral recombency: 最常用 颈部要垫高，头部要永远比颈部低 good exposure of buccal surfaces of the upper teeth and fai

19、r exposure of lingual surfaces of the opposite teeth，所以在过程中一定会需要翻身,Routine periodontal treatment,Dorsal recombency 最好的视野，尤其是上颚齿 通常在治疗过程中不用改变体位 best for surgical extraction of the caudal maxillary teeth 最主要的危险是aspiration 1.使用砂袋或毛巾垫高颈部 2.确保硬颚与桌面平行 3.桌子的头侧稍向下斜,Routine periodontal treatment,cuffed endo-

20、tube 不要用mouth gag，1cc syringe较好 pharyngeal pack Avoid patient become unnecessary wet Tilted table with adequate drainage Plastic pad under the body Circulating warm water blanket,Routine periodontal treatment,工作区域 不建议在手术室做牙周治疗 ,room should be well ventilated sterilize instrument tray every time full

21、 aseptic technique for surgical extraction operator in a seated position,Routine periodontal treatment,Personal protection Mask (effective up to 8 hours), disposible Protective eyewear or goggle,Routine periodontal treatment,清醒检查(戴手套) Lips Occlusion overcrowding of teeth abnormal direction of canine

22、s jaw length abnormalities Enamel hypoplasia 工具,Periodontal probe and explorer,一侧是dental probe，钝头、有刻度，用来测量深度(刻度有3-mm color-coding, 1mm coding, etc) evaluate gingiva health (tissue consistency, gingival bleeding measure attached gingiva survey gingival sulcus and pocket (walk along the bottom of pock

23、et) 深度称为probing depth，以前用pocket depth 不理想,Periodontal probe and explorer 一侧是explorer，尖头。用来探测洞、不平滑、furcation等hard tissue lesion。 Dental mirror,Routine periodontal treatment口腔检查(Dental chart,Calculus 0：无齿石 1: 25%crown以下覆盖 2: 25-50% crown 覆盖 3: 50-75% crown 覆盖 4: 75%以上crown覆盖,Routine periodontal treatm

24、ent口腔检查(Dental chart,Gingivitis 0：normal gingiva, no inflammation, no discoloration, no bleeding 1：mild inflam, slight color change, no bleeding 2：moderate inflam, erythema, swelling, bleeding on probing 3: severe inflam, spontaneous hemorrhage, some ulceration,Routine periodontal treatment口腔检查(Dent

25、al chart,Mobility 0：normal 1：增加活动 2：活动超过0.5mm 3：活动超过1mm 4：高度活动，牙无功能,Routine periodontal treatment口腔检查(Dental chart,Furcation 0：no 1：3 mm probed in horizontal 2：more than 3 mm 3：through and through furcation,Routine periodontal treatment,Removal of supra and subgingival calculus and plaque by periodo

26、ntal debridement removal of pathogenic plaque and toxins from the crown (with the help of bactericidal lavage also) and root surface without removing exposed cementum. 移除calculus及exposed cementum现在被认为不是最重要，最重要的是必须要移除gingiva pocket中的plaque,Routine periodontal treatmentPower scaler,Machines Ultrasonic

27、 (20000 Hz)：以metal tip vibration 及cavitation来移除calculus及消毒。 tip愈薄，产热愈多,Routine periodontal treatmentPower scaler,Sonic scaler oscillate between 2000-6000 Hz Come with air-driven machine Less powerful , but less damaging to the tooth surface Little or no heat generated,Routine periodontal treatmentPo

28、wer scaler,Principles Never press hard on the tip: it relies on vibration to effect. Adequate water spray (水可以降温，而且在超音波后形成泡沫及震波，造成细菌细胞壁的破坏 (cavitation，气穴现象)。有的机器还能用antiseptic solution,Never spend more than 5-10 seconds on one tooth Do not use the tip subgingivally (unless specially designed) Do not

29、direct the tip at a 90 degree to the enamel surface,Routine periodontal treatmenthand instruments,periodontal sickle scaler 尖头，用来remove supragingival calculus 种类：(有混合两头的，称为Towner-Jacquette scaler) straight (Jacquette scaler): 2 straight blades ，背面三角较钝 curved: 2 curved blades，背面三角较锐 使用：blade与平面呈45-90

30、度，以pull stroke来移除calculus，可在ultrasonic scaler前使用,Routine periodontal treatmenthand instruments,Periodontal curettes 圆头，圆背，主要用于 remove subgingival calculus and debris，也可以用于移除gingival margin 附近的supragingival calculus。 种类： universal curette: 2 blades, 刃面与杆呈90度，双面都可以用，用于curette牙根面及sulcus epithelium (gin

31、gival curettage) Gracey curette: 刃面与杆呈70度，一般只用一个刃面，为area-specific，每一支都只用于特定的区域，刃长及形状都稍有不同,Routine periodontal treatment,Extraction (if indicated) 1.Teeth affected by Holmstrom stage 4 periodontal disease are irreversible are best extracted. (尤其是居家清洁无法达成，牙松动，且有grade-3 fucation lesion者) Disclosing sol

32、ution 在perodontal debridement之后用，可以显示plaque(pink) 及calculus (blue) 如果还有plaque可以用polish，如果还有calculus则必须用scalingSelective polishing,Routine periodontal treatment,Cup polishing 用可弃式的橡皮cup装在prophy-angle接头，采用低速handpiece. Cup振动的方式为旋转或摆动(oscillate)，其中以摆动较好。旋转式要小心勿卷入毛。 用pediatric size cup Pumice (浮石): 可以使用b

33、ulk, fine-grade dry pumice 或特制的fine phophy-paste，放在cup上polish时要随时添加pumice 及水,转速以不超过5000 rpm为原则，最好是3000 rpm，Light touch/ short time的原则，每颗牙5-7秒。 allow the cup to flare out on the tooth surface to clean both the supragingival crown and subgingival surface.Air polishing Irrigation: 0.05% chlorhexidine g

34、luconate,Routine periodontal treatment,Air polishing: Medical-grade sodium bicarbonate crystals and water in a jet of compressed air to “sandblast” the surface smooth. 对兽医来说，更为理想，因为不接触牙齿，速度快，而且充份polish缝隙，但是价钱较贵,Routine periodontal treatment,Irrigation: 0.05% chlorhexidine gluconate to remove prophy-

35、paste and other debris。有人也会用fluoride treatment，氟会硬化enamel，并且会使exposed dentin较不敏感。但不知道对狗猫是否有同样效果,Dental power equipment,功能：scaling, polishing and drilling 电动式： Scaler Magnetostrictive Piezoelectric Micromotor (slow speed: 200-30000 rpm) (for polish and drilling) 特色： Polish 通常用2000-3000 rpm Section通常用10000