Orthodontic perspective

With the addition of fixed appliances, the risk of demineralization can only be compounded, as the presence of brackets, archwires, ligatures, and other orthodontic devices make maintaining proper oral hygiene even more difficult, leading to plaque accumulation and ultimately demineralization around brackets in as little as 4 weeks time. The prevalence of new enamel lesions among orthodontic patients treated with fixed appliances, even with the use of fluoride toothpaste, can range anywhere from 13% to 75%. Children aged 11–14 years are considered to be at greatest risk of developing caries.1 Studies have estimated the prevalence of white spot lesions (WSLs) after orthodontic treatment to be as high as 97%.2 WSLs are particularly detrimental in a field that focuses on the esthetic outcome of their patients, more so, as these lesions mainly occur in the maxillary anterior dental region3 (Figure 1). Several approaches can be employed to help reduce the occurrence of WSLs, such as more frequent professional cleanings and reinforcing oral hygiene instructions, using applied behavior analysis (ABA), and the use of chemotherapeutic agents, which can also reduce the incidence of WSLs by means of specifically targeting the disease-producing microorganisms. The use of resin-modified glass ionomer (RMGI) cements has been investigated in the past as a means to prevent cavities. There have also been studies conducted using glass ionomer cements with cariesprevention capabilities to bond orthodontic brackets. In a study conducted by Kashani, et al., it was shown that when comparing enamel demineralization depths adjacent to bands cemented with zinc polycarboxylate, glass ionomer (GI) and RMGI, the use of RMGI cement seems to present significantly better prevention of enamel demineralization.4 Unfortunately, there is a downside to the use of RMGI cements. These materials have low bond strength, as demonstrated by the work of Bishara, et al.5 Their results showed significantly reduced shear bond strength when compared with that of the conventional composite resin adhesive system. Orthodontists and their patients are better served by an adhesive system that provides clinically reliable bond strength. The ideal preventative treatment is one that does not rely on patient compliance at all. If there was a one-visit, cure-all prevention that could be implemented on the initial day of bracket placement and need no subsequent follow-up, no further research would be needed. Research has established that fluoride is a very effective means of caries prevention. Subsequent to water fluoridation, there was a decrease in childhood caries by 15%-40%. Fluoride rinses, and toothpastes such as PreviDent® 5000 Plus® (Colgate®) contribute to additional reduction in caries. However, careful at-home flossing, brushing with fluoridated pastes, and using fluoride rinses rely heavily on meticulous compliance from children and adolescents. An alternative to these methods of fluoride administration is a longer lasting fluoride treatment done professionally to ensure that patients receive the appropriate amount of fluoride — i.e., fluoride varnish applications, provided by dentists who would ensure the varnish is applied properly to a dried tooth surface. But what do we already know about the prevention of WSLs using fluoride varnish? When plaque accumulates around orthodontic brackets, it causes a perfect storm. Plaque is a natural reservoir for cariogenic microflora, namely Streptococcus mutans and Lactobacilli.6 This leads to demineralization of the enamel around the brackets leading to white spot lesions. A particularly effective way to prevent WSLs, and ultimately decay, is to apply fluoride varnish to An orthodontic perspective on white spot lesions: part 2