DIAGNOSIS/TREATMENT/PROGNOSIS

ARTICLE ANALYSIS & EVALUATION

ARTICLE TITLE ANDBIBLIOGRAPHICINFORMATION

Risk factors for incidence andseverity of white spot lesions duringtreatment with fixed orthodonticappliances.

Chapman JA, Roberts WE, Eckert GJ,Kula KS, Cabezas CG.

Am J Orthod Dentofacial Orthop2010;138:188-94.

REVIEWER

Philip Benson, PhD, FDS (Orth)

PURPOSE/QUESTION

What is the incidence ofdemineralized white lesionsoccurring in orthodontic patientstreated with fixed orthodonticappliances in a graduate orthodonticclinic in Indianapolis, IN?

SOURCE OF FUNDING

Information not available

TYPE OF STUDY/DESIGN

Cohort study

LEVEL OF EVIDENCE

Level 2: Limited-quality,patient-oriented evidence

STRENGTH OFRECOMMENDATION GRADE

Not applicable

J Evid Base Dent Pract 2011;11:105-1061532-3382/$36.00� 2011 Elsevier Inc. All rights reserved.doi:10.1016/j.jebdp.2011.03.012

One-third of Orthodontic PatientsReceiving Fixed Appliances in a USGraduate Clinic have New IatrogenicDemineralized White Lesions at theEnd of Treatment

SUMMARY

SubjectsThis study consisted of 332 consecutively finished orthodontic patientstreated in a graduate orthodontic clinic in Indianapolis, IN. Sixty-two per-cent were female and 73% were white. Themean age was 16.2 years (SD 8.7;range 8 to 56 years). Study participants were recruited in the 2006 and 2007academic years. There were quite a few exclusion criteria and it is not clearhow many patients were screened and how many were excluded.

Key Exposure/Study FactorOrthodontic patients treated with fixed braces placed on the outside sur-faces of the teeth.

Main Outcome MeasureThe main outcome was the presence or absence of new demineralizedwhite lesions (DWLs) on the labial surface of the upper 8 front teeth (firstpremolar to first premolar). This was assessed from before-treatment andafter-treatment clinical photographs of the teeth by one examiner super-vised by a second investigator.

A secondary outcome was the size of the lesions as measured by handtracing around the DWLs using a computer-image analysis program and ex-pressed as a percentage of the whole tooth surface.

Main ResultsOf a total of 332 patients receiving labial fixed braces, 118 (36%) had atleast one new DWL on the labial surface of the upper front teeth followingtreatment. In 46 patients (14%), the DWL covered more than 10% of thetotal tooth surface.

The odds of developing a DWL during treatment were 6 times greater fora patient with fair or poor oral hygiene before the start of treatment com-pared with those who had good oral hygiene.

ConclusionsOral hygiene is important in preventing the occurrence of unsightly DWLsduring treatment with fixed braces on the labial surfaces of teeth.

COMMENTARYANDANALYSIS

Orthodontic treatment is an elective procedure, principally undertaken toimprove the appearance of the teeth. It is therefore disappointing to bothpatient and clinician if there are unsightly demineralized white lesions(DWLs), particularly on the upper anterior teeth, when the braces are re-moved. Although this is a well-recognized complication, particularly when

JOURNAL OF EVIDENCE-BASED DENTAL PRACTICE

fixed appliances are used, it is perhaps surprising that fig-ures for the incidence of the condition are so variable.

This unfortunate lack of information is mainly becauseof the different methodologies used in previous studies.For example, most investigators have assessed the cross-sectional prevalence of DWLs only when the braces areremoved. This study has correctly determined the devel-opment of new DWLs (ie, the difference between the startand finish of treatment or incidence). In some previousstudies it is difficult to distinguish between the propor-tion of patients who develop at least one DWL and theproportion of teeth affected by DWLs. This study distin-guishes between these data, which are both importantto know. Previous studies have examined all the teeth,even if they are toward the back of the mouth or in thelower jaw and thus not visible. This study assessed DWLsonly on the upper anterior teeth, which are likely to beof most esthetic concern to patients.

Other differences between studies have been in themethod of recording the presence of DWLs. Previousstudies have used clinical assessments, which may be sub-ject to inter- or intraexaminer variability, whereas thisstudy used before-treatment and after-treatment photo-graphs. Clinical images may have limitations in terms ofstandardization of the technique and overestimating theproblem because of reflection from the flash, but in myopinion this is still the best approach. The use of clinicalphotographs also allowed the investigators to determinethe severity of the lesions by measuring the size and ex-pressing this as a proportion of the tooth surface, whichagain is a useful measurement.

The study is not without some problems. The authorscollected data only from consecutively finished cases,whereas it would have been better to have chosen consec-utively started cases. By selecting cases at the end, ratherthan the beginning, it is possible that there was some se-lection bias. For example, clinicians might have decidednot to take clinical photographs of their worst cases, in

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which the braces were removed early. The investigatorsalso state that they excluded patients with ‘‘poor qualityor inadequately angled digital photographs, incompleterecords, [and] limited treatment or retreatment,’’ whichalso introduces selection bias, and it would have been use-ful if the authors had given some indication of how manypatients were excluded for these reasons.

In 17% of the patients, the braces were removed early,but no definition was given as to the reason for earlyremoval of braces. Was it the clinician’s decision, thepatient’s request, or a combination of the two? It is alsonot clear how the investigators measured compliance, asopposed to oral hygiene, particularly with the multipleoperators involved. I also think it is a little unfair that theirlogistic regression model suggests that conventional metalbrackets were a risk factor for the development of DWLs, asby far the majority of patients were treated with metalbrackets as opposed to ceramic or self-ligating brackets.

The most useful finding for me as a practicing clinician(apart from the incidence data) is the conclusion that byfar the strongest predictor for developing DWLs duringfixed orthodontic treatment was the presence of eitherfair or poor oral hygiene at initial appointment. Those pa-tients were 6 times more likely to have DWLs at the end oftreatment than patients with good oral hygiene at the ini-tial appointment. It is therefore essential for all cliniciansto objectively and rigorously screen all their patients be-fore they start treatment with braces to ensure that thiscommon side effect is minimized.

REVIEWER

Philip Benson, PhD, FDS (Orth)Reader in Orthodontics/Honorary Consultant in OrthodonticsAcademic Unit of Oral Health and DevelopmentSchool of Clinical DentistryUniversity of Sheffield, UKp.benson@sheffield.ac.uk

June 2011