title: Orthodontic treatment-related white spot lesions: a 14-year prospective quantitative follow-up, including bonding material assessment.
abstract: BACKGROUND
  White spots (WS) related to orthodontic treatment are severe cariologic and cosmetic complications, but they are shown to be partially reduced by remineralization or abrasion in short-term follow-ups. In this prospective study, we quantitatively analyzed changes in WS in general and in treatment-related white spot lesions (WSL) during orthodontic treatment and at a 12-year follow-up after treatment. In addition, we quantitatively compared the effects of an acrylic bonding material vs a glass ionomer cement (GIC) on WSL.
  
  
  METHODS
  Sum areas of WS and WSL were calculated on scans of standardized photos of the vestibular surfaces of 4 teeth in consecutive orthodontic patients (median treatment time, 1.7 years) bonded with the 2 materials in a split-mouth design. Comparisons were made in 59 patients before treatment (BF), at debonding (T0), at 1 year (T1), and at 2 years (T2), and in 30 patients at a 12-year follow-up (T3) with the Friedman test followed by pairwise comparisons with the Wilcoxon matched-pairs signed rank test. Differences of the effects of acrylic vs GIC on the sum areas of WSL were tested for each observation period with the Mann-Whitney U test.
  
  
  RESULTS
  Increases in the sum areas of WS and WSL from BF to T0 (P <0.001) were followed by significant decreases at T1 (P <0.001) and T2 (P <0.01 for WS; P <0.001 for WSL). Significant changes were also found in the sum areas for WS at T3 compared with T2 (P <0.01), but not for WSL (P = 0.328). The sum areas of WS and WSL at T3 did not return to BF levels (P <0.001). Sum areas of WSL were higher for surfaces bonded with acrylic compared with GIC for each observation period from BF to T2 (P >0.001), and from T2 to T3 (P >0.05).
  
  
  CONCLUSIONS
  Although significantly reduced during the 12-year follow-up and significantly lower with the GIC than the acrylic material at bonding, WSL are a cariologic and cosmetic problem for many orthodontic patients.
authors.affiliation: Department of Odontology/Orthodontics, Umeå University, Umeå, Sweden. dmsh0001@student.umu.se
authors.forename: Dmitry
authors.initials: D
authors.lastname: Shungin
authors.forename: Alexandra Ioannidis
authors.initials: AI
authors.lastname: Olsson
authors.forename: Maurits
authors.initials: M
authors.lastname: Persson
mesh_terms: D000180:Acrylic Resins / Q000009:adverse effects / Q000737:chemistry; D000293:Adolescent; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000737:chemistry; D001840:Dental Bonding / Q000009:adverse effects* / Q000379:methods; D003731:Dental Caries / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control; D017005:Dental Debonding; D003743:Dental Enamel / Q000473:pathology; D005260:Female; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000737:chemistry; D005500:Follow-Up Studies; D005899:Glass Ionomer Cements / Q000009:adverse effects / Q000737:chemistry; D006801:Humans; D008297:Male; D009967:Orthodontic Appliances / Q000009:adverse effects*; D009971:Orthodontics, Corrective / Q000009:adverse effects / Q000295:instrumentation; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D017001:Tooth Demineralization / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000180:Acrylic Resins; D002327:Cariostatic Agents; D005460:Fluorides, Topical; D005899:Glass Ionomer Cements