Comparison of Self-Etch Primers with Conventional Acid Etching System on Orthodontic Brackets.

INTRODUCTION: The self-etching primer system consists of etchant and primer dispersed in a single unit. The etching and priming are merged as a single step leading to fewer stages in bonding procedure and reduction in the number of steps that also reduces the chance of introduction of error, resulting in saving time for the clinician. It also results in smaller extent of enamel decalcification. AIM: To compare the Shear Bond Strength (SBS) of orthodontic bracket bonded with Self-Etch Primers (SEP) and conventional acid etching system and to study the surface appearance of teeth after debonding; etching with conventional acid etch and self-etch priming, using stereomicroscope. MATERIALS AND METHODS: Five Groups (n=20) were created randomly from a total of 100 extracted premolars. In a control Group A, etching of enamel was done with 37% phosphoric acid and bonding of stainless steel brackets with Transbond XT (3M Unitek, Monrovia, California). Enamel conditioning in left over four Groups was done with self-etching primers and adhesives as follows: Group B-Transbond Plus (3M Unitek), Group C Xeno V+ (Dentsply), Group D-G-Bond (GC), Group E-One-Coat (Coltene). The Adhesive Remnant Index (ARI) score was also evaluated. Additionally, the surface roughness using profilometer were observed. RESULTS: Mean SBS of Group A was 18.26±7.5MPa, Group B was 10.93±4.02MPa, Group C was 6.88±2.91MPa while of Group D was 7.78±4.13MPa and Group E was 10.39±5.22MPa respectively. In conventional group ARI scores shows that over half of the adhesive was remaining on the surface of tooth (score 1 to 3). In self-etching primer groups ARI scores show that there was no or minor amount of adhesive remaining on the surface of tooth (score 4 and 5). SEP produces a lesser surface roughness on the enamel than conventional etching. However, statistical analysis shows significant correlation (p<0.001) of bond strength with surface roughness of enamel. CONCLUSION: All groups might show clinically useful SBS values and Transbond XT can be successfully used for bracket bonding after enamel conditioning with any of the SEPs tested. The SEPs used in Groups C (Xeno V+) and D (G-Bond) have significantly lowered SBS. Although, the values might still be clinically acceptable.

The direct way of indirect bonding--the combined effect.

The placement of orthodontic bonded brackets may be accomplished by either a direct or indirect technique. Most orthodontists will agree that brackets can be positioned more accurately on study casts than directly on teeth in the mouth. And, also direct bonding is more demanding to the orthodontist. Yet, very few orthodontists routinely use an indirect bonding technique. The reasons commonly given for not using the indirect method are difficulty in achieving consistent and predictable adhesion to the teeth, excess of composite around the bracket margins, failure to get all the brackets to adhere to the teeth e the expense of the materials. These disadvantages can be overcome by a new simplified method of bonding outlined in this article; additionally it has advantages of direct bonding also.

The use of silane-coated industrial glass fibers in splinting periodontally mobile teeth.

In the past, direct stabilization and splinting of teeth using an adhesive technique required the use of wires, pins, or mesh grids. Problems with the current fiber reinforcement materials are their inherent thickness when embedded within composite resin, their availability in fixed widths and their high cost. This paper discusses the use of silane-coated industrial grade glass fibers, which can be bundled in the form of ribbon according to the required thickness and length. Of the three patients discussed in this paper, none has exhibited debonding or recurrent caries over 1-year period. By reinforcing composite splints with these industrial grade glass fibers, dentists can provide patients with restorations and splints that are economical, fracture resistant, and more durable than most alternative splinting materials of the past.