A. 湿性龋 B.慢性龋 C. 干性龋 D. 继发龋 E.猛性龋 31 Which is the best way of pain control for endodontic treatment A.Local anesthetics B.Devitalization C. Analgesics D. Occlusal reduction E.Incising and drainage 32 Which one is not the reason for use of rubber dam A.Protect aspiration or swallowing of instruments or irrigants B.Eliminate the dental fear of patients C.Improve visibility D.Reduced risk of cross-contamination E.Legal considerations 33 The following statements are correct except A.Nearly all canals exhibit a certain degree of curvature. B.There may be more than one canals within one root. C.The apical foramen usually opens at the anatomical apex. D.Apical constriction occurs at 0.5~1mm from the apical foramen E.Lateral and accessory canals might be the cause of treatment failure. 34 Which one is wrong regarding the principle of access cavity A Straight-line access B Conservation of tooth structure C Unroofing of the chamber and exposure of pulp horns D Facial surface of anterior teeth E Occlusal surface of posterior teeth 35 The ad vantages of gutta-percha as a filling material are A.It is compactible and adapts excellently to the irregularities and contour of the canal B.It is radiopaque C.It can be easily removed from the canal when necessary D.It can be softened and made plastic by heat or by organic solvents E.All of the above 36 Which one is incorrect about the criteria of the root canal is ready to be filled after the completion of root canal cleaning and shaping? A.The tooth is asymptomatic.A. 湿性龋 B. 慢性龋 C. 干性龋 D. 继发龋 E. 猛性龋 31 Which is the best way of pain control for endodontic treatment A. Local anesthetics B. Devitalization C. Analgesics D. Occlusal reduction E. Incising and drainage 32 Which one is not the reason for use of rubber dam A. Protect aspiration or swallowing of instruments or irrigants B. Eliminate the dental fear of patients C. Improve visibility D. Reduced risk of cross-contamination E. Legal considerations 33 The following statements are correct except A. Nearly all canals exhibit a certain degree of curvature. B. There may be more than one canals within one root. C. The apical foramen usually opens at the anatomical apex. D. Apical constriction occurs at 0.5~1mm from the apical foramen. E. Lateral and accessory canals might be the cause of treatment failure. 34 Which one is wrong regarding the principle of access cavity A Straight-line access B Conservation of tooth structure C Unroofing of the chamber and exposure of pulp horns D Facial surface of anterior teeth E Occlusal surface of posterior teeth 35 The advantages of gutta-percha as a filling material are A. It is compactible and adapts excellently to the irregularities and contour of the canal B. It is radiopaque C. It can be easily removed from the canal when necessary D. It can be softened and made plastic by heat or by organic solvents E. All of the above 36 Which one is incorrect about the criteria of the root canal is ready to be filled after the completion of root canal cleaning and shaping? A. The tooth is asymptomatic