Potential Remineralization of Postorthodontic Demineralized Enamel and the Use of Enamel Microabrasion and Bleaching for Esthetics

White spot lesions in fixed orthodontic treatment: Etiology, pathophysiology, diagnosis, treatment, and future research perspectives

White spot lesions (WSLs) refer to localized areas of hypo-mineralization limited to the enamel of the teeth surface, which is noticeable clinically to the naked eye on drying of the teeth. During fixed orthodontic treatment, it is very hard for the patient to maintain excellent oral hygiene as the brackets, bands, wires, elastics, and other appliances and attachments worn intra-orally provide a platform for food retention, plaque formation, and then colonization by acidogenic bacteria like Streptococcus mutans and Lactobacillus. This review aims to elaborate and focus on etiology, pathophysiology, diagnosis, treatment aspect, and future scope for research about the WSLs occurring due to fixed orthodontic treatment.

Resin infiltration in white spot lesions caused by orthodontic hypomineralisation: a minimally invasive therapy

Objective White spot lesions are characterised by the presence of clinically detectable opaque lesions due to enamel demineralisation. These frequently present in patients following fixed orthodontic treatment, mostly due to the prolonged accumulation of bacterial plaque on the dental surface. When remineralisation is not achieved through good oral hygiene and prophylaxis with fluoride products, the infiltration of lesions with low-viscosity photopolymerised resin has proved to be a valid micro-invasive alternative compared to traditional conservative therapy.Clinical considerations A case series will be presented, where the chosen approach was resin infiltration, a micro-invasive and aesthetic technique.Clinical significance Infiltrative resin therapies are single-session procedures that reduce the need for more invasive therapies such as the use of rotary instruments for greater patient comfort. The need for periodic fluoride applications is also avoided. This approach increases the durability of the infiltrated lesion without compromising its mechanical properties and impedes the development of recurrent or secondary caries.Conclusions Resin infiltration might be considered as a routine procedure in the treatment of post-eruptive hypomineralised lesions. This follows the line of thought of minimally invasive dentistry, is an excellent treatment option and prevents the lesion's progression.

Reducing white spot lesion incidence during fixed appliance therapy

Fixed orthodontic appliances are commonly used in contemporary orthodontic treatment and can be associated with the development of white spot lesions on the teeth. These lesions can be detrimental to both the aesthetics and health of the teeth so prevention is better than cure and patient selection is critical. This paper discusses predictors of development in addition to methods to help prevent white spot lesions during fixed appliance therapy. Recommendations for oral hygiene regimes during fixed orthodontic appliance treatment are given, the development of white spot lesions (WSLs) described and ways to predict their occurrence identified.

CLINICAL RELEVANCE

Most general dental practitioners will have patients who are considering orthodontic treatment or are wearing fixed orthodontic appliances and so are at increased risk of developing WSLs. It is therefore important they are aware of predictors and ways to prevent WSLs.

Treatment of white spot lesions with ACP paste and microabrasion

OBJECTIVE

To examine the effects of application of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) paste and microabrasion treatment on the regression of white spot lesions (WSLs).

MATERIALS AND METHODS

Artificially-induced WSLs in bovine enamel were randomly assigned to one of four treatment groups: CPP-ACP paste only, microabrasion only, microabrasion and CPP-ACP, and a control. Samples were treated with each regimen twice daily for 2 weeks and stored in remineralizing solution between the treatments. Quantitative light-induced fluorescence was used to measure changes in fluorescence, which indicate changes in mineral content of WSLs immediately before (T1) and 2 weeks after treatment (T2). A two-within-subject factor analysis of variance was used to analyze the significance of any changes in mineral content of the lesions from T1 to T2.

RESULTS

There was a statistically significant (P < .05) gain in fluorescence associated with the microabrasion only, as well as the microabrasion and CPP-ACP treatments. The changes in fluorescence for the CPP-ACP treatment alone were not statistically significant (P  =  .40).

CONCLUSIONS

CPP-ACP paste alone does not significantly improve the fluorescence value (ie, the mineral content) of WSLs. Within the limitations of this in vitro study, microabrasion treatment with or without CPP-ACP improved the fluorescence and thus reduced WSLs.

Preventing and treating white-spot lesions associated with orthodontic treatment: a survey of general dentists and orthodontists

BACKGROUND

The authors investigated the prevention and treatment of white-spot lesions (WSLs) during and after orthodontic therapy from the perspective of general dentists and orthodontists.

METHODS

The authors administered a cross-sectional survey to general dentists (n = 191) and orthodontists (n = 305) in Virginia, Maryland and North Carolina.

RESULTS

Sixty-nine percent of general dentists and 76 percent of orthodontists recommended in-office fluoride treatment for patients with severe WSLs immediately after orthodontic treatment. Sixty-nine percent of general dentists reported that they had treated WSLs during the previous year, and 37 percent of orthodontists reported that they had removed braces because of patients' poor oral hygiene. Sixty percent of orthodontists referred patients with WSLs to general dentists for treatment. Eighty-five percent of orthodontists responded that they encouraged patients to use a fluoride rinse as a preventive measure. More than one-third of general dentists indicated that severe WSLs after orthodontic treatment could have a negative effect on their perception of the treating orthodontist.

CONCLUSIONS

WSLs are a common complication of orthodontic treatment and their presence can result in a negative perception of the treating orthodontist by the patient's general dentist. Clinical implications. General dentists and orthodontists should work together to prevent the development of WSLs in their patients. Treatment with fluoride supplements and motivating and training patients to practice good oral hygiene will help achieve this goal. Treatment after debonding should include the topical application of low concentrations of fluoride.

Effects of demineralizaton-inhibition procedures on the bond strength of brackets bonded to demineralized enamel surface

Objective

To study and compare the effects of different demineralization-inhibition methods on the shear bond strength (SBS) and fracture mode of an adhesive used to bond orthodontic brackets to demineralized enamel surfaces.

Methods

Eighty freshly extracted, human maxillary premolars were divided into 4 equal groups and demineralized over the course of 21 days. Brackets were bonded to the demineralized enamel of teeth in Group 1. In Group 2, bonding was performed following resin infiltration (ICON®, DMG, Hamburg, Germany). Before bonding, pre-treatment with acidulated phosphate fluoride (APF) or solutions containing casein phosphopeptide-amorphous calcium phosphate with 2% neutral sodium fluoride (CPP-ACP/wF) was performed in Groups 3 and 4, respectively. The SBS values of the brackets were measured and recorded following mechanical shearing of the bracket from the tooth surface. The adhesive remnant index (ARI) scores were determined after the brackets failed. Statistical comparisons were performed using one-way ANOVA, Tukey's post-tests, and G-tests.

Results

Significant differences were found in some of the intergroup comparisons of the SBS values (F = 39.287, p < 0.001). No significant differences were found between the values for the APF-gel and control groups, whereas significantly higher SBS values were recorded for the resin-infiltrated and CPP-ACP/wF-treated groups. The ARI scores were also significantly different among the 4 groups (p < 0.001).

Conclusions

Tooth surfaces exposed to resin infiltration and CPP-ACP/wF application showed higher debonding forces than the untreated, demineralized surfaces.

Do enamel microabrasion and casein phosphopeptide-amorphous calcium phosphate affect shear bond strength of orthodontic brackets bonded to a demineralized enamel surface?

Objective:

To evaluate and compare the effects of enamel microabrasion, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and their combination on the shear bond strength (SBS) of orthodontic brackets bonded to demineralized enamel surface.

Materials and Methods:

One hundred human first premolar teeth were randomly allocated to one of five groups. Group I was considered as the control of other groups. For the remaining groups, demineralization was performed via solutions. In group II, brackets were directly bonded to the demineralized enamel surface. CPP-ACP was applied in group III, microabrasion was performed in group IV, and both microabrasion and CPP-ACP application were performed in group V. The specimens were tested for SBS. Bond failures were scored according to the Adhesive Remnant Index (ARI). Analysis of variance and Tukey tests were used to compare the SBS of the groups. ARI scores of the groups were evaluated with a G-test. The statistical significance was set at P &lt;. 05 level.

Results:

Statistically significant difference was found among the five investigated groups (F  =  111.870; P &lt; .001). The SBS of groups II and IV were significantly lower than the other groups. No statistically significant difference was found among groups I (control; mean 24.1 ± 4.1 MPa), III (mean 22.0 ± 3.6 MPa), and V (mean 24.3 ± 1.9 MPa). Microabrasion and combination with CPP-ACP showed higher SBS compared to the control group. The differences between ARI scores of the groups were statistically significant (P &lt; .001).

Conclusion:

CPP-ACP pretreatment, microabrasion of the enamel, and the combination of these two methods improve the bonding to demineralized enamel.

Do fluoride and casein phosphopeptide-amorphous calcium phosphate affect shear bond strength of orthodontic brackets bonded to a demineralized enamel surface?

OBJECTIVE

To compare the effects of fluoride and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing topical agents on shear bond strength (SBS) and fracture mode of orthodontic brackets bonded to demineralized enamel.

MATERIALS AND METHODS

Eighty freshly extracted human premolar teeth were randomly divided into four equal groups. The first group was the control, and no pretreatment was performed on this group. In the remaining three groups, demineralization process was performed and teeth were stored in artificial saliva. In group II, bonding was performed after demineralization. Pretreatment with fluoride and CPP-ACP gels was performed in groups III and IV, respectively. Brackets were bonded using a conventional system. The SBS of these brackets was measured and recorded in MPa. Adhesive remnant index (ARI) scores were determined after the brackets failed. Data were analyzed with analysis of variance (ANOVA), Tukey, and G-tests at the P < .05 level.

RESULTS

ANOVA comparison of four groups revealed statistically significant differences. No significant differences were found between control and CPP-ACP-treated groups. However, lower SBS values were recorded for group II (6.6 ± 3.9 MPa) and group III (17.1 ± 2.9 MPa). ARI scores were significantly different among the four groups (P < .001). No enamel detachment was found in the control group, and enamel detachment measured 75% for group II.

CONCLUSIONS

Fluoride and CPP-ACP gel applications showed higher debonding forces compared to bonding in untreated demineralized samples. CPP-ACP pretreatment resulted in comparable SBS values compared with the control group.