ABSTRACT
The pretreatment of dentin with cross-linking agents during bonding procedures has been proposed to improve the mechanical properties of the collagen in the hybrid layer and reduce the biodegradation of the adhesive interface. The aim of this study was to evaluate the influence of pretreatment with two carbodiimides on the dentin bond strength of universal adhesives, after thermocycling. Three universal adhesives in the self-etching mode were used (Single Bond Universal-SBU, Clearfil Universal-CLU and Ambar Universal-ABU). A self-etching adhesive system (Clearfil SE Bond-CSB) was used as control. Two carbodiimides, 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide (EDC) and N,N'-dicyclohexylcarbodiimide (DCC), were applied for 1 min. The excess solution was removed with absorbent paper and the universal adhesives were applied. The specimens were stored for 24 h in distilled water at 37 °C or 10,000 thermal cycles (5-55 °C, 30 s) and then were prepared for microtensile bond strength test (n = 4 teeth, average of 21 sticks per group). Data were analyzed using three-way ANOVA and Tukey's (α = 5%). After 24 h, SBU and CSB had statistically similar bond strength values for the control groups (22.07 ± 9.03 and 19.82 ± 7.28 MPa), with EDC (30.21 ± 11.30 and 19.67 ± 5.36 MPa) and DCC (30.12 ± 13.43 and 19.82 ± 7.28 MPa) pretreatments (p > 0.05). The use of EDC (32.57 ± 9.60 MPa) and DCC (24.71 ± 9.87 MPa) showed statistically higher bond strength for CLU than for the control group (14.62 ± 6.16 MPa; p < 0.05). After thermocycling, the SBU, CLU, and CSB groups showed statistically similar bond strengths with the use of EDC (27.08 ± 8.44; 18.74 ± 5.41; and 24.55 ± 10.43 MPa) and without the use of cross linkers (20.06 ± 7.99; 22.55 ± 9.04; and 26.54 ± 10.13 MPa; p > 0.05). Groups tested after 24 h in distilled water presented higher bond strength than those submitted to thermocycling. It can be concluded that the use of cross linkers influenced the immediate bond strength of the universal adhesives, and this was dependent on the combination of the adhesive system and type of carbodiimide. The use of EDC increased the immediate bond strength of CLU. DCC increased the bond strength of ABU at 24 h, but the values were lower than those of the control group after aging for three out of the four adhesives.
Subject(s)
Dental Bonding , Dentin-Bonding Agents , Adhesives , Carbodiimides , Composite Resins , Dental Cements , Dentin , Materials Testing , Resin Cements , Tensile StrengthABSTRACT
Resumo Este artigo descreve o tratamento ortodôntico de uma paciente jovem de 20 anos com má oclusão de Classe III. O plano de tratamento consistia em distalizar ambos os quadrantes posteriores inferiores para corrigir a má oclusão de Classe III. Além disso os objetivos do tratamento também incluíam a correção da mordida cruzada posterior e do apinhamento ântero- -inferior. Dois mini-implantes foram posicionados entre os segundos pré-molares e primeiros molares inferiores com o intuito de serem utilizados como ancoragem indireta. Molas espirais abertas foram utilizadas para a distalização, além do auxílio de elásticos de Classe III. O período total de tratamento foi de 24 meses. Ao final do tratamento, uma excelente oclusão foi obtida na paciente, juntamente com uma melhora no seu perfil facial. (AU)
Abstract This article describes the orthodontic treatment of a 20-year-old female patient with Class III malocclusion. The treatment plan consisted of distalizing both lower posterior quadrants to correct Class III malocclusion. In addition, treatment goals also included correction of posterior crossbite and anteroinferior crowding. Two mini-implants were placed between the second premolars and mandibular first molars in order to be used as indirect anchorage. Open spiral springs were used for distalization, in addition to the aid of Class III elastics. The total treatment period was 24 months. At the end of the treatment, an excellent occlusion was achieved in the patient along with an improvement in her facial profile (AU)
Subject(s)
Humans , Adult , Orthodontics , Orthodontic Anchorage Procedures , Malocclusion, Angle Class IIIABSTRACT
The aim of this paper is to describe a restorative approach to the cosmetic remodeling of the teeth of a young adult patient with right maxillary lateral hypodontia and left lateral microdontia. A conservative restorative management was proposed to improve smile esthetics by combining direct composite resins and ceramics. Initially, periodontal therapy and dental bleaching were performed. Subsequently, direct composite resins were applied to the central incisors and canines to reestablish the sizes and shapes of these teeth. Finally, ceramics were placed on the implant and the microdontia to unite with the new alignment and color of the anterior teeth. Thus, conservative remodeling to improve the harmony of the smile was provided.
