Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Part 2 book “Textbook of preclinical conservative dentistry” has contents: Principles of tooth preparation, tooth preparation for amalgam and composite restorations, tooth preparation for primary teeth, dental materials, adhesive dentistry, and other contents. | CHAPTER 8 Principles of Tooth Preparation Nisha Garg CHAPTER OUTLINE Introduction Purpose of Tooth Preparation Classification Definitions Number of Line and Point Angles INTRODUCTION Tooth preparation is the mechanical alteration of a defective, injured or diseased tooth in order to best receive a restorative material which will re-establish the healthy state of the tooth including esthetic correction when indicated along with normal form and function. Steps Initial Stage Final Stage Viva Questions CLASSIFICATION Tooth preparation is classified according to location of the tooth defect (Fig. 8.1). Class I is the only pit and fissure preparation whereas rest are smooth surface preparations. r Class I: Pit and fissure preparations occur on the occlusal surfaces of premolars and molars, the occlusal PURPOSE OF TOOTH PREPARATION two-third of buccal and lingual surface of molars and lingual surface of incisors (Figs 8.2A and B) Earlier when the affected tooth was prepared because of caries, cutting of tooth was referred to as cavity r Class II: Preparations on the proximal surface of premolars and molars are class II (Figs 8.3A and B) preparation. But nowadays many indications other than r Class III: Preparations on the proximal surface of anterior caries lead to preparation of the tooth. Hence, the term teeth and not involving the incisal angles are class III cavity preparation has been replaced by tooth preparation. (Figs 8.4A and B) Tooth preparation is done for: r Class IV: Preparations on the proximal surface of r 5SFBUNFOU PG DBSJPVT UFFUI anterior teeth also involving the incisal angle falls under r 5SFBUNFOU PG NBMGPSNFE GSBDUVSFE PS USBVNBUJ[FE class IV (Figs 8.5A and B) teeth r Class V: Preparations on gingival third of facial and r 3FQMBDFNFOU PG PME EFGFDUJWF SFTUPSBUJPOT lingual or palatal surfaces of all teeth came under Class V r &TUIFUJD JNQSPWFNFOU GPS EJTDPMPSFE BOE VOFTUIFUJD (Figs 8.6A and .
