When it comes to treating stains on teeth, a single agent may not always be enough. In such cases, combining different bleaching techniques can be the best solution. Depending on the type of discoloration, there are various options available. Table 15.3 outlines the different combinations for different levels of discoloration.
When one agent is not able to completely remove a stain, or when there are multiple stains from different sources on the same tooth, a combination of whitening methods can be used. Intensive whitening can be combined with a home whitening program (Garber et al.). Different concentrations of bleaching agents can also be used in combination. Microabrasion can be combined with household bleaching or electrical bleaching. Pumice stone and a 10% carbamide peroxide suspension can also be used to whiten teeth (Baker et al.).Increasing concentrations of hydrochloric acid and resin infiltration can also reduce the effects of white spots.
There are more opportunities to combine whitening treatments and more techniques for more effective whitening. Over-the-counter products such as toothpastes, whitening strips, and gels that are painted directly on the teeth or delivered in trays are also available. Before beginning any treatment, it is important to take pre-treatment shades for both the non-vital tooth and the surrounding teeth. This should be recorded in the patient's medical record or on the whitening record sheet (see chapter). The patient should then be sent home with instructions and enough whitening materials to brighten the tooth. The access cavity should be left open so that the whitening material (usually 10% or 16% carbamide peroxide or 6% hydrogen peroxide) can be placed in the pulp chamber while a whitening tray is applied to the tooth to keep the material in place.
The thicker base of glass ionomer can sometimes mask residual discoloration if the non-vital tooth has not been fully whitened to match adjacent teeth. Patients who have undergone tooth-colored restorations (including crowns or implants) should be aware that the whitening agent will only affect natural teeth and that the treatment could cause differences between natural teeth and restorations, as they will not change color. The study excluded patients who had previously undergone teeth whitening procedures or had previous teeth with restorations on the lip surfaces, veneers or complete crowns, gingival recession in the front teeth, spontaneous dental pain, previous teeth treated with endodontics, fluorosis, severe internal discoloration of the teeth, teeth with non-carious cervical lesions, or bruising habits.