1、Operative Dentistry,郑沛,Operative Dentistry,Operative dentistry is the art and science of the diagnosis, treatment, and prognosis of defects of teeth which do not require full coverage restorations for correction.,enamel,pulpodentinal complex,cementum,Periodontal,牙体修复原则,去净龋坏牙体组织 保守治疗的原则 抗力形和固位形,充填材料的
2、选择,性能要求物理和机械，化学，生物学选择要点牙齿部位，窝洞部位和咬合力，病人情况，其他因素,Cavity Preparation,The mechanical alteration of a defective , injured, or diseased tooth in order to best receive a restorative material which will re-establish a healthy state for the tooth including esthetic corrections where indicated, along with nor
3、mal form and function.,Classification of cavity,Cavities may be classified according to the location where the carious lesion begins Class Class Class Class Class Class ,G.V.Black in 1908,Class I,All pit and fissure cavities are Class I. Cavities on occlusal surface; Cavities on occlusal two-thirds
4、of the facial and lingual surfaces of molars; Cavities on lingual surface of maxillary incisor.,Class II,A cavity occurring on the proximal surface of posterior teeth are Class II.MO mesial and occlusal DO distal and occlusal MOD mesial, occlusal and dista,Class III,Cavities on the proximal surfaces
5、 of anterior teeth that do not involve the incisal angles are Class III.,Class IV,Cavities on the proximal surfaces of anterior teeth that do involve the incisal angles are Class IV.,Class V,Cavities on the gingival third of the facial or lingual surfaces of all teeth ( not pit and fissure cavities
6、) are Class V.,Class VI,Cavities on the incisal edge of anterior teeth or the occlusal cusp heights of posterior teeth are Class VI.,Cavity,Simple cavity: only one tooth surface is involved.,Compound cavity: two surfaces are involved.,Complex cavity: three or more surfaces are involved.,Cavity Struc
7、ture,walls angles cavity,Walls,Internal walls: a prepared cavity surface that does not extend to the external tooth surface.,Axial walls: an internal wall parallel with the long axis of the tooth and occlusal of the tooth.,Pulpal walls: an internal wall that is both perpendicular to the long axis of
8、 the tooth and occlusal of the pulp.,a side or surface of the cavity preparation that aids in enclosing the restorative material.,Walls,External walls: a prepared cavity surface that extend to the external tooth surface.The external walls takes the name of the tooth surface that the wall is toward.,
9、.,Angles,Line angle: the junction of the two planal surfaces of different orientation along a line.,Angles,Point angle: the junction of three planal surfaces of different orientation.,Angles,Cavosurface angle: the angle of tooth structure formed by the junction of a prepared cavity wall and the exte
10、rnal surface of the tooth.,Also referred to as the cavity margin or cavosurface margin.,Resistance Form,定义 洞深： 盒状洞形 阶梯结构 窝洞外形 去除无机釉 薄壁弱尖的处理,Retention form,Lateral retention undercut dovetailtrapezia adhesive,深龋的治疗,原则： 正确判断牙髓状况,治疗方法,垫底充填,安抚治疗,间接盖髓术,治疗方案,根面龋,保守治疗,充填治疗,窝洞预备的基本原则,Removal of Remaining Ca
11、riesWhen the dentin has a firm feel with the explorer, removal of the tooth structure should cease, even if stained dentin remains. 只需去除感染牙本质（崩解层和透入层） 根据硬度和着色两个标准来判断,二、保护牙髓组织间断操作，锋利器械，冷却不向髓腔加压了解解剖结构、增龄变化,三、尽量保留健康牙体组织最小程度扩展洞形龈缘位置尽量不做预防性扩展釉质成形术 enameloplasty,注意患者全身状况,窝洞预备基本步骤,The design of the cavity
12、preparation for either a tooth with initial caries or replacement restoration is based on the location of the caries, the amount and extent of the caries, the amount of lost tooth structure, and the restorative material to be used.,一、预备洞形 1、开阔洞口及进入病变区：不同窝洞进入通道的选择,2、设计预备洞的外形以病变为基础扩展避开承受咬合力的部位圆滑曲线The
13、dentist must establish an outline form, which determines the overall shape of the preparation along the cavity margins of the restoration and the tooth surfaces. The outline form is determined by the size and shape of the carious lesion and by the need for a suitable design that will hold a restorat
14、ion firmly in place.,邻面的颊舌洞缘位置,在规定的深度扩展洞形,3、抗力形和固位形,4、Finishing the Enamel Walls and Margins This is a process of angling, beveling, and smoothing the walls of the cavity preparation to achieve the best marginal seal possible between the restorative material and tooth structure. The dentist may use
15、burs, diamond stones, or hand-cutting instruments (chisels, hoes, hatchets, and gingival margin trimmers) to complete the walls by removing loose or unsupported enamel to create the strongest possible enamel wall.,5、无痛制洞法锋利器械，正确手法局部麻醉 anesthesia化学机械去龋,二、术区隔离棉卷隔离,Reasons for use of rubber dam,Protect
16、ion aspiration or swallowing of instruments or irrigants Soft tissue injury caused by instruments Efficiency Improve visibility (dry field and reduced mirror fogging) Minimize patient conversation Minimize the need for frequent rinsing Reduced risk of cross-contamination Legal considerations,Four-ha
17、nded dentistry Close support 四手操作,选择性辅助隔离法：refraction cord,mouth prop,三、窝洞消毒,CAVITY LINERS AND BASES are used primarily to protect the pulp and to aid the pulp in recovering from irritation resulting from cavity preparation.1、窝洞封闭：洞漆、树脂粘结剂2、衬洞：隔绝化学和温度刺激常用洞衬剂3、垫底：隔绝温度、化学、电流及机械刺激。常用材料,根据余留牙本质的厚度和修复材料的种类选用不同的封闭剂、洞衬剂和（或）垫底材料 垫底的部位,银汞合金修复术,适应症,、类洞 后牙类洞 美观要求不高，尖牙远中邻面洞 配合附加固位钉 冠修复前的牙体充填,窝洞预备,洞形要求,、类洞不同洞形的制备要求,银汞合金充填,护髓 成形片和楔子,填充材料：少量分次，层层加压,雕刻成形,调整咬合 打磨抛光：24小时完全硬固,并发症,意外穿髓 疼痛牙髓性牙周性,充填体折断,牙齿折裂,继发龋,患者，男，2岁， 主诉：右下后牙冷刺激痛2周，无自发痛 体检：颌面颊沟深龋，探诊（），质较硬，冷诊（），冷刺激去除疼痛快速缓解，叩诊（）。,
