Assessment of Coated Orthodontic Miniscrews With Chlorhexidine Hexametaphosphate Antimicrobial Nanoparticles

Anchorage management by using of OMS to give anchoring for force application made using several orthodontic treatment techniques simple and improved their efficacy , because anchorage control is a challenge throughout the orthodontic treatment process till temporary orthodontic anchorage devices have been developed. Although stainless steel (SS) screws were initially introduced, the majority of currently presented OMS are manufactured from titanium (purity grades I to IV). Because they offer greater mechanical strength and reduce the danger of fracture during insertion and removal, titanium alloy miniscrews are typically employed. Failure of these devices is the most frequent issue related to the usage of OMSs. The development of a biofilm on these devices that causes periimplantitis is one of the recognized reasons for failure.

Primary stability (mechanical stability) is awarded shortly after the placement procedure of the device and secondary stability (biological stability) initiates at the placement time and enhances during the process of healing or bone remodeling. The first 8 weeks after insertion, during which time the stability of the implant transitions from mechanical to biological stability, are when OMS failure occurs most frequently. Although failure might be prevented by following the right protocols of treatment, the fact that, rate of failure of OMS could not be overlooked. The miniscrew's mobility and displacement, together with an infection of the soft tissues around, are causes of failure. Unmodified titanium and its alloys are prone to bacterial infections which lead to inflammation and failure of the implant eventually. Prevention of bacterial adhesion may inhibit biofilm formation.

Antibiotics used for protection against implant infection postoperatively is debatable due to inducing the process of antimicrobial resistance, substitute techniques to avoid this must be inspected. There are three recent solutions that have the ability to prevent the formation of biofilm on miniimplant surfaces. These include altering the topography of surfaces to prevent bacterial adhesion, treating surfaces with antimicrobial releasing agents for a set period of time to prevent bacterial adhesion, as well as eliminating bacteria nearby, and, finally, coating surfaces with antimicrobial agents that prevent attachment of bacteria over an extended period of time. The previous study on human dermal fibroblast of neonate cells showed that both coated and uncoated titanium OMSs were non-cytotoxic, furthermore, the animal study showed enhanced bone-remodeling process.

The research question is 'Does coating orthodontic mini-screws with CHX-HMP NPs increase their success rate?

Inclusion criteria

• Undergoing orthodontic treatment by fixed orthodontic appliance.
• Indicated for a bilateral miniscrews.
• Good oral hygiene.

Exclusion criteria

• Medically compromised patients.
• Heavy smoker.
• Dry mouth ( Xerostomia).
• mucogingival lesions.
• Patients with chlorhexidine allergy.