0000000000358687
AUTHOR
Bart Vande Vannet
Root repair after injury from mini-screw
Mini-implants and mini-screws are commonly used in orthodontics to provide extra anchorage. One potential insertion site is between the roots in the alveolar process, which results in a risk of damaging the roots of neighbouring teeth. In an animal-experimental study, 20 mini-screws (bracket screw bone anchors, BSBAs) were inserted into the mandible of five beagle dogs. Each dog received two BSBAs in each lower quadrant, between the roots of the second and third, and third and fourth premolars. Sequential point labelling was performed every 6 weeks with vital stains, and apical X-rays were taken every 6 weeks. Radiographic examination demonstrated damage at three roots because of insertion …
The use of three-dimensional oral mucosa cell cultures to assess the toxicity of soldered and welded wires
The aim of the present study was to determine whether there is a difference in toxicity and loss of viability of three-dimensional (3D) reconstructed human oral epithelium (RHOE) cell cultures induced by point-welded (PW), laser-welded (LW), and silver-soldered (SiS) orthodontic wires. Three types of soldered stainless steel (SS) wires: PW, LW, and SiS were prepared ( n = 3) and subjected to multiple end-point analysis (MEA). Six pieces were cut from each wire. Each piece was placed on the triplicate cell cultures (RHOE model based on TR 146 cells). After 24 hours of topical exposure, the cell cultures were cut and stained with haematoxylin/eosin. Toxicity was assessed by evaluating the mor…
Toxicity of used orthodontic archwires assessed by three-dimensional cell culture
The aim of the present study was to determine whether used orthodontic wires made of different materials cause toxicity and loss of viability on three-dimensional (3D) cell cultures. Three types of orthodontic wires, stainless steel, Nitinol, and TMA (n = 9) which had been used clinically in fixed appliances for a period of 1 month, were retrieved at random from five patients. Both upper and lower archwires were collected and subjected to two different protocols: to assess toxicity, two pieces of each wire were placed on 3D cell cultures (reconstituted human epithelium); to investigate the possibility of cell damage, the 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide (MTT) ass…
Osseointegration of miniscrews: a histomorphometric evaluation.
SUMMARY Mini-implants and miniscrews are commonly used in orthodontics to provide additional temporary intraoral anchorage. Partial osseointegration represents a distinct advantage in orthodontic applications, allowing effective anchorage to be combined with easy insertion and removal. This article reports the histomorphometric fi ndings of the osseointegration of bracket screw bone anchors (BSBAs). In an experimental animal study, four BSBAs were inserted in the alveolar process of the lower jaw in each of fi ve male beagle dogs, aged 6.5 months from the same mother. Eleven screws were lost during the study, nine of them due to lack of primary stability. One screw was removed at the end of…