title: Effect of sonic and ultrasonic retrograde cavity preparation on the integrity of root apices of freshly extracted human teeth: scanning electron microscopy analysis.
abstract: Sonic and ultrasonic root-end preparation devices permit the preparation of conservative and straight cavities. However, microfractures and marginal chipping can occur due to the vibratory action of such instruments. The purpose of this study was to evaluate the effect of retrograde preparations by using sonic and ultrasonic tips on the integrity of root-end surfaces. Eighty, human anterior teeth were grouped according to size and treated as follows: treatment 1: root-end resection (RR) and root-end cavity preparation (RP) with KIS ultrasonic retrotip; treatment 2: RR and RP with Satelec S12/90 (no diamond coating) ultrasonic retrotip; treatment 3: RR and RP with a diamond-coated retrotip attached to a sonic device (Sonics); treatment 4: RR and RP with Satelec S12/90D (diamond coated) ultrasonic retrotip. The root-end surface topographies were assayed by means of polyvinylsiloxane impressions and epoxy resin replicas. SEM pictures of each sample were taken before and after preparation, and the images were evaluated by using an image processing and analysis system. The parameters evaluated were shape quality, presence of cracks, and marginal chipping. The results showed no statistically significant differences among anatomic groups, treatments, or tooth sizes (p > 0.05). Because treatment 3 removed more dental structure than the others did, its use on small teeth is inadvisable.
authors.affiliation: Endodontic Unit, School of Dentistry of Piracicaba, State University of Campinas-UNICAMP-Piracicaba-SP, Brazil.
authors.forename: Eudes
authors.initials: E
authors.lastname: Gondim
authors.forename: Brenda Paula Figueiredo Almeida de
authors.initials: BP
authors.lastname: Gomes
authors.forename: Caio Cesar Randi
authors.initials: CC
authors.lastname: Ferraz
authors.forename: Fabricio Batista
authors.initials: FB
authors.lastname: Teixeira
authors.forename: Francisco José de
authors.initials: FJ
authors.lastname: Souza-Filho
mesh_terms: D001047:Apicoectomy / Q000295:instrumentation / Q000379:methods; D003739:Dental Cementum / Q000648:ultrastructure; D003760:Dental Impression Materials; D003786:Dental Pulp Cavity / Q000293:injuries / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure; D018130:Diamond; D004853:Epoxy Resins; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008855:Microscopy, Electron, Scanning; D008903:Minerals; D011145:Polyvinyls; D016628:Replica Techniques; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D012833:Siloxanes; D013016:Sound; D013223:Statistics as Topic; D013499:Surface Properties; D019227:Tooth Apex / Q000293:injuries / Q000648:ultrastructure*; D014465:Ultrasonics
chemical_list: D003760:Dental Impression Materials; D004853:Epoxy Resins; D008903:Minerals; D011145:Polyvinyls; D012833:Siloxanes; C034183:vinyl polysiloxane; D018130:Diamond