Prevalence of white-spot lesions before and during orthodontic treatment with fixed appliances

The aim of the study was to determine the prevalence of white-spot lesions (WSLs) in patientswith fixed orthodontic appliances. The cross-sectional study sample consisted of three groups of patients:group I, 59 patients treated orthodontically for 6 months; group II, 64 patients treated for 12 months;group 0 (control), 68 patients examined immediately before appliance placement. All groups were treatedwith a 0.022-inch slot preadjusted appliance and they wore a functional fixed appliance. The presence ofWSLs was evaluated by visual examination using the scoring system proposed by Gorelick. The groupswere evaluated for differences in the prevalence of at least one WSL using Fisher’s exact test, followedby Bonferroni pairwise comparisons. The prevalence of WSLs by tooth type was evaluated with logisticregression (P < 0.05). Intraobserver agreement was assessed by means of the Cohen ĸ statisticalmethod. There were no significant differences in the prevalence of WSLs between patients treated for 6and 12 months (P = 0.855); however, there were significantly more WSLs in groups I and II than in group0 (P = 0.000). No significant differences were found between girls and boys (P = 1.000). The mandibularfirst molars and maxillary lateral incisors were the most affected teeth, in both the treated and untreatedgroups. The study revealed significant decalcification at 6 months after orthodontic bonding. Consideringhow quickly these lesions can develop and become irreversible, early diagnosis is of critical importance.