In vitro cytotoxic effects of orthodontic appliances

Abstract

The objective of this study was to evaluate the effects of an orthodontic appliance and of its components (brackets, bands, and arch wires) on some cell functions. Fibroblasts were cultured either in the presence of one unwashed orthodontic appliance, or one orthodontic appliance immersed in MEM for 28 days before use (washed appliance), or in the presence of MEM in which the appliances had been immersed. At the end of in vitro maintenance, morphological studies were carried out with SEM and TEM. Cell proliferation and GAG synthesis and secretion by radio-labeled precursors were assessed. The data indicated that unwashed appliances were more cytotoxic than washed ones. Moreover, the arch wire was the most biocompatible component of the orthodontic appliance, and the bracket was the least biocompatible. A comparative study into the effects on cell proliferation of the most common metal ions released by the appliances was also carried out. At the concentration released by one orthodontic appliance immersed for 28 days, the highest reduction in DNA synthesis was observed in the presence of Cu(++).

Biocompatibility of orthodontic bands following exposure to dental plaque

“…Es wurde kein Unterschied in der Fibroblastenanhaftung ermittelt. Locci et al [22] erhielten ähnliche Ergebnisse, nachdem sie die Biokompatibilität von "gewaschenen" d.h. 28 Tage in "minimal essential medium" eingetauchten, und "ungewaschenen" orthodontischen Bändern verglichen.…”

“…They detected no difference in fibroblast adhesion. Locci et al [22] attained similar results when comparing the biocompatibility of unwashed versus washed (immersed in minimal essential medium for 28 days) orthodontic bands.…”

Applications of Current Technologies for Nondestructive Testing of Dental Biomaterials

“…However, this is only an assumption and the verification of galvanic corrosion requires further extended research. The important contribution of this NDT and X-ray EDS analysis is significant because it confirms other previous findings that Ag-based alloys are prone to corrosion and ionic release (Grimsdottir et al 1992;Locci et al 2000a;Mockers et al 2002;Staffolani et al 1999). These findings might be a reason for mucosal irritation, which was reported in a previous study (Bishara 1995).…”

Biocompatibility evaluation of sputtered zirconium-based thin film metallic glass-coated steels

“…9 The high ionic strength, warm temperature, and high number of microorganisms in the human body can cause biodegradation of implant materials such that the patient may be exposed to corrosive products and suffer unwanted bioreactions. 10 To protect and enhance metallic implants from wear and corrosion and to improve their biocompatibility, substantial surface modification techniques and coatings have been used to deposit a variety of functional coatings on the surfaces of metallic implants. Surface modifications are often undertaken to biomedical implants to improve their resistance to corrosion and wear, surface texture, and biocompatibility.…”