Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 1463706

An easily removable ceramic bracket?

N A Fox·J F McCabe
View original source ↗Export metadata ↓

Abstract

The use of ceramic brackets in fixed appliance orthodontics has highlighted several problems, amongst which are the problems of enamel damage and possible trauma to the patient during debonding. A ceramic bracket has recently been developed with a polycarbonate laminated base (Ceramaflex) claiming to make debond much easier, although there are no independent data to substantiate this claim. The in-vitro bond strength of these ceramic brackets to enamel was tested and compared with metal standard Edgewise brackets. The bond produced with the Ceramaflex bracket was similar in magnitude, but less reliable. No fracture of the bracket or damage to enamel was seen during debonding. Debonding of these brackets was easy to carry out, but it is possible that more debonds may occur during treatment than with the use of metal brackets.

Explore related subjects

AdhesivesCeramicsDental AlloysDental BondingDental DebondingDental EnamelDental Stress AnalysisHumansMaterials TestingOrthodontic Appliance DesignOrthodontic BracketsPlasticizersPolycarboxylate CementStress, MechanicalSurface PropertiesComparative StudyJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

N A Fox, J F McCabe. 1992. An easily removable ceramic bracket?. https://doi.org/10.1179/bjo.19.4.305

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2005

Effects of sodium hypochlorite gel and sodium hypochlorite solution on dentin bond strength.

The aim of this study was to determine the effect of 10% NaOCl gel and 10% NaOCl solution on dentin bond strengths of four adhesive systems. One hundred eighty bovine incisors were ground to achieve a flat polished surface, then divided into 12 groups: Gluma One Bond [G1-control; G2-NaOCl solution; G3-NaOCl gel]; Prime & Bond 2.1 [G4-control; G5-NaOCl solution; G6-NaOCl gel]; Single Bond [G7-control; G8-NaOCl solution; G9-NaOCl gel]; Prime & Bond NT [G10-control; G11-NaOCl solution; G12-NaOCl gel]. Dentin was etched, rinsed, and blot dried. For the experimental groups, after acid etching, 10% NaOCl solution or 10% NaOCl gel was applied for 60 s, rinsed, and blot dried. Composite resin was inserted and light cured. Shear bond strengths were tested with a crosshead speed of 0.5 mm/min. The mean values MPa (SD) were analyzed with two-way ANOVA and Tukey's tests (alpha < 0.01). Ten percent NaOCl solution significantly increased Gluma One Bond strength. No effect was observed for the other adhesives. The 10% NaOCl gel did not affect bond strengths. Ten percent NaOCl gel was less effective on collagen removal as compared to 10% NaOCl solution. The influence of collagen removal on bond strength is dependent on adhesive system, where both the solvent and the monomer can influence the results.

Adhesives↗
PubMed2005

Mechanical resistance of a new biomaterial, ostrich pericardium, and a new method of joining tissues combining suturing and a biological adhesive.

We studied the mechanical behavior in response to tensile stress of samples of ostrich pericardium bonded with a cyanoacrylate glue or sewn with a rectangular, overlapping suture that was subsequently sealed with the same bioadhesive. Seventy-two trials were performed in three series of 24 samples each: series AG, glued with an overlap of 1 cm2; series ASG, sewn with a rectangular, overlapping suture and sealed; and series AC, control samples that were left intact. The mean stress at rupture in series AG (glued) was 0.1 MPa, much lower than the working stress of a human valve leaflet, which is approximately 0.25 MPa. In the control series, this stress was 26.28 MPa. At rupture in series ASG (sutured/glued), the suture material was being subjected to a stress of 64.91 MPa, thus confirming the existence of an interaction between the suture and the shear stress exerted by the suture on the samples of pericardium. In series ASG, the mean value for the resistance to rupture when measured in machine kg was 8.83 kg, lower than but similar to that recorded in the control series AC (10.26 kg). The percentages of reversible deformation, or elongation, once the samples were torn were similar in series AC (19.15%) and ASG (21.93%). This phenomenon can only be explained by the damage to the collagen fibers in the area around the rupture, while other more distant regions work at a lower load within the elastic limit. We conclude that cyanocrylate adhesives alone are not suitable as bonding materials in cardiac bioprostheses. The results with the rectangular, overlapping suture, when subsequently sealed with an adhesive, can be considered good because, although this approach does not impede shear stress, it does maintain an excellent degree of resistance to rupture of the samples thus joined. We stress the need to take into account the concentration of the load in the design of bioprostheses.

Adhesives↗