Toothpaste Use Protocol with Dental Bleaching for a Conservative Treatment: Case Reports.

In-office bleaching is a treatment based on products that contain hydrogen peroxide (HP) while demonstrating whitening effectiveness. HP could promote alterations to surface morphologies and properties of dental tissues. The objective was describe a toothpaste protocol associated to bleaching therapy to promote a safer approach. Patient 1 (male) and Patient 2 (female) were attended, and toothbrushing (twice a day) with a dentifrice containing bioactive glass (BG) (NovaMin™) and fluoride was indicated before and during the treatment. Three bleaching sessions were made in cases, at intervals of 7 days. The gels used were 35% HP (Patient 1) and 35% HP supplied with calcium (Patient 2). The effectiveness of bleaching treatment was observed in both cases (Vita scale), with an esthetic self-acceptance. Sensitivity associated with the procedure was not reported. The indication of BG-based toothpaste is relevant in relation to enamel properties and did not affect the whitening effectiveness of dental bleaching.

Introduction

Dental esthetics is been more valued in contemporary society. Among the treatments for dental color change, dental bleaching has been vastly indicated, since this procedure is considered esthetic, minimally invasive, relatively safe, and effective.[1] During the whitening procedures, hydrogen peroxide (HP) acts as an oxidizing agent over the pigment molecules deposited in the dental structure. The oxidative effect of HP could promote an alteration in composition of dental substrates,[2] affecting the physicochemical properties of the tooth.[23]

With the objective of decreasing or controlling these adverse effects, different compounds, especially remineralizing agents, have been used. A previous in vitro study[4] demonstrated that the application of a dentifrice containing bioactive glass (BG) before the bleaching treatment was efficient in protecting the enamel against mineral loss promoted by HP. Thus, the objective of these case reports was to describe the effects of the bleaching therapy associated with a commercial toothpaste containing BG.

Case Reports

These case reports involve two patients that were previously advised as to the right of anonymity based on the ethical precepts applied to clinical cases. Patient 1 – male (31 years old) – and Patient 2 – female (21 years old) –had a dental appointment at Piracicaba Dental School (University of Campinas, Piracicaba, São Paulo, Brazil) complaining of the cosmetic look of their darkened teeth. Based on a clinical examination, the patients presented with good oral hygiene and an absence of carious lesions or periodontal disease. Before beginning the treatment (1 week), toothbrushing with a dentifrice containing BG (NovaMin™, Sensodyne Repair and Protect, GlaxoSmithKline, Berkshire, United Kingdom) was indicated for both patients. Information of products used in this case report is detailed in Table 1.

Table 1

Technical information of the products used

Clinical procedures

Before bleaching, prophylaxis and digital photographs to obtain patients’ tooth shades [Figures 1 and 2] were performed. The tooth color was assessed under a natural light environment and classified in accordance to the Vitapan Classic scale (Zahnfabrik H., Germany). Patient 1 presented an upper incisors with a shade of A1 and upper canines with a shade of A2, and lower teeth (incisors and canines) with a shade of A2 [Figure 2]. Meanwhile, Patient 2 presented with shade A1 for the upper and lower incisors and A2 for the upper and lower canines [Figure 1].

Figure 1

Initial shade in accordance to Vita scale, Patient 1: (a) Upper incisors – A1; (b) Upper canines – A2; (c) Lower incisors – A2; (d) Lower canines – A2. Final shade for Patient 1: (e) Upper incisors – B1; (f) Upper canines – B1; (g) Lower incisors – A1; (h) Lower canines – A1. Whitening procedure: (i) Reddish appearance of the bleaching gel at the beginning of the application; (j) Greenish aspect of the bleaching gel after the radical oxygen saturation

Figure 2

(a) Toothbrushing. (b and c) Bleaching agent (with calcium supply) application. Initial shade in accordance to Vita scale, Patient 2: (d) Upper incisors – A1; (e) Upper canines – A2; (f) Lower incisors – A1; (g) Lower canines – A2. Final shade for Patient 2: (h) Upper incisors – B1; (i) Upper canines – B1; (j) Lower incisors – B1; (k) Lower canines – B1

Labial retractors were used for Patient 1 (FGM Dental Products, Joinville, SC, Brazil). Patient 2 was treated using the Expandex lip retractor (Indusbello, Londrina, PR, Brazil). For both cases, a desensitizing agent containing 5% potassium nitrate and 2% sodium fluoride (KF 2% desensitize, FGM Dental Products, Joinville, SC, Brazil) was applied for 10 min, whose purpose was to reduce possible sensitivity.

The gingival tissues were then isolated using a light-cured gingival barrier (Topdam, FGM Dental Products, Joinville, SC, Brazil) to avoid contact between the bleaching gel and the gingiva. Furthermore, Patient 1 presented with the presence of cracks and incisal enamel wear with exposed dentin. Thus, to prevent excessive diffusion of HP, these areas were also protected with the light-cured gingival barrier [Figure 1].

Three in-office bleaching sessions were made in both cases, at intervals of 7 days between each session. Three applications of 15 min at each session [Figure 2] of HP (35% Whiteness HP Maxx, FGM Dental Products, Joinville, SC, Brazil) were performed, according to the manufacturer's instructions. For Patient 2, a single application of 35% HP containing calcium (Whiteness HP Blue Calcium, FGM Dental Products, Joinville, SC, Brazil), for 40 min [Figure 1] at each session, was applied, according to the manufacturer's instructions.

At the end of each session, for both treatments, the bleaching gels were removed with a disposable aspirator and the teeth were washed with water. Figure 3 shows the finished appearance after the bleaching treatment, demonstrating the effectiveness of the whitening procedure. It is possible to note a change of tooth shades [Figures 1 and 2] when comparing to the initial shade. Sensitivity associated with both bleaching procedures was not reported. Esthetic self-acceptance and whiteness effectiveness were observed.

Figure 3

Final aspect of the bleaching treatment for Patient 1: (a) Intraoral; (b) Smile. Final appearance of the bleaching treatment for Patient 2: (c) Intraoral; (d) Smile

Discussion

Dental bleaching is an effective treatment that promotes better smile esthetics with safety and predictability,[5] although deleterious effects can occur. Among these effects, the literature has described some damages to dental hard tissues,[24567] including: decrease in microhardness, alteration in surface roughness, and increase in permeability. The intensity of these side effects could be associated to the study model or storage conditions of the specimens.[8] Saliva plays an essential role in creating an active environment for remineralization; nevertheless, products have been studied to decrease the side effects of tooth whitening.

The aim of this case report was to explore the management and protocols that provide secure treatment, principally in relation to the enamel substrate. For Patient 2, a whitening gel with calcium was chosen. This gel provides a supersaturated amount of calcium, which is an important participant ion in the demineralization and remineralization processes of teeth. Moreover, the BG incorporated into the toothpaste was indicated for patients to protect the enamel against the adverse effects promoted by whitening procedures.[4]

BG is a highly biocompatible material based on calcium (Ca), sodium (Na), phosphorus (P), and silica (SiO2).[9] The BG reacts with the substrate surface to increase the concentration of Ca, Na, and Pions, resulting in the repair of the demineralized surface or remineralization[9] and demonstrating high bioactivity. When in contact with saliva, bioglass provides an increase of free Ca2+, PO43−, and Na+, which are attracted to the dentin collagen and enamel surface.[9] This process results in the formation of a protective layer that is chemically similar to the natural apatite of tooth,[9] which is enhanced by the presence of fluoride. This protective layer that is enriched with mineral ions could act as a reservoir of ions during the demineralization processes.[9]

In the current literature, although the toothpaste containing BG shows efficacy for the treatment of dentin hypersensitivity,[10] there is no evidence of a tooth sensitivity control during in-office bleaching treatment. Therefore, it is possible to hypothesize that the mineral precipitates formed by the reactivity of the toothpaste with the dental substrate could be important, especially in the presence of enamel cracks, as seen in Patient 1, since it could act as a physical barrier in an area of high diffusion of HP. Nevertheless, in vivo studies are required to investigate the role of this toothpaste in controlling tooth sensitivity promoted by HP diffusion. On the other hand, the use of a product containing potassium nitrate – which acts directly in depolarizing pulp cells, decreases the pain transmission, and causes an analgesic effect – is an effective method for tooth sensitivity control during the whitening procedures.[11]

The BG-based toothpaste used before and between the bleaching sessions was indicated not only for enamel remineralization but also to decrease potential mineral loss, based on minimally invasive dentistry. Toothbrushing is crucial in routine hygiene habits, and its indication by the dentist is important to maintain the patient's oral health.

Conclusion

The use of toothpaste containing BG is beneficial in relation to enamel properties, and the clinical results obtained from the case reports demonstrated that the use of toothpaste did not affect the whitening effectiveness of dental bleaching.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.