Diametral tensile strength, michrohardness, surface modulus, and surface morphology of novel, antimicrobial orthodontic adhesives

• Main Author: Godel, Jeffrey H
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01.01.2016
• Subjects: Dentistry
• ISBN: 9781369483185; 136948318X

Objective: Prior to the advent of bonded orthodontic appliances each tooth was fitted with a band made from stainless steel. Traditionally they were cemented to the tooth with a zinc phosphate cement. This acted more as a luting agent then adding to the actual adherence of the band to the tooth. In addition, often times the cement would wash out and upon the band removal white spot lesions and or carious lesions were present. The development of glass monomer cements had a traumatic improvement over both the adhesion to the tooth and a diminishing of white spot lesions in part due to the release of fluoride. Since the advent of the acid-etch technique and the bonding of orthodontic brackets directly to the enamel various bonding adhesives were developed. The first and most popular bonding resins were chemical curing bonding systems. The general class of self-adhesive and/or self-etching orthodontic adhesives are of several types, including resin-modified cements, such as resin-modified glass ionomer cements, that exhibit self-adhesive properties to enamel, as well as self-etching primers that combine the conditioning and priming agents into one acidic, polymerizable composition for application to the tooth surface, and do not require separate etching and rinsing steps. Not only do resin modified glass ionomers have the benefit of chemically bonding to a clean and un-etched enamel surface, but these self-adhesive cements also release significant and continuous levels of fluoride ion. Recently investigators have explored adding antimicrobial agents in addition to fluoride in orthodontic adhesives. One such approach has been the addition of ZnO powder, a known compound with anti-microbial properties, to an orthodontic resin modified glass ionomer adhesive. It should also be noted that zinc ions and compounds have been shown to positively influence enamel remineralization and enhance apatite formation. The objective of this research is to evaluate the effect of the addition of an antimicrobial agent, zinc oxide powder, on selected mechanical properties of a resin modified glass ionomer orthodontic adhesive. (Abstract shortened by ProQuest.)