Researchers at the Oregon Health & Science University School of Dentistry have found the majority of patients with self-ligating orthodontic brackets retain fewer bacteria in plaque than patients with elastomeric orthodontic brackets.
The OHSU team also found that a biochemical technique measuring ATP- (adenosine triphosphate-) driven bioluminescence could be a useful chair-side tool in the rapid quantification of oral bacteria and in the assessment of oral hygiene during orthodontic treatment.
The findings are published in the April 2009 issue of the American Journal of Orthodontics and Dentofacial Orthopedics, one of the leading peer-reviewed orthodontia journals.
Acid-producing bacteria that surround orthodontic appliances are a common orthodontic problem. Such bacteria can lead to tooth enamel breakdown and potential discoloration of the tooth surface, and these aesthetic changes can persist for many years after orthodontic treatment. While the newer bonded orthodontic brackets have many advantages over the old metal bands that were fitted around each tooth, they do impede good oral hygiene, resulting in plaque accumulation and increased tooth enamel breakdown.
While several studies have investigated the effects of fixed orthodontic appliances on bacterial flora, few studies have compared the effects of bracket architecture – specifically the archwire ligation method – or have evaluated the accumulation of bacteria that occurs with the bonding of fixed appliances. The OHSU study also was different from other studies in that it was a randomized clinical study, comparing the numbers of oral bacteria in plaque surrounding two distinct orthodontic appliances, self-ligating versus elastomeric ligating, using a split-mouth design.