May 08, 2020
Every patient dreams of going to the dentist with the hope that he does not feel any pain during the treatment and walks out of the clinic with an esthetic smile. Enamel microabrasion is one such procedure, which is not only painless and efficient but also conservative and minimal.
As the name suggests, enamel microabrasion is a procedure carried out only for lesions that are restricted to the enamel. More often, this procedure is used to remove the stains and irregularities within the enamel.
An LED light curing unit is used for diagnosing the extent of the enamel lesion. A darker color indicates deeper staining. Moreover, this is done in wet conditions since the reflective index between air and enamel might give false results. A lesion visible on wet tooth is considered deeper than a lesion visible on dry enamel.
Enamel microabrasion technique
This procedure has a long history behind it. First proposed in 1926, this procedure utilized 36% hydrochloric acid and a hot metallic instrument that helped in the penetration of the acid. The chemicals used in microabrasion gradually changed from 36% HCl to 18% HCl to 10% HCl.
As far as instrumentation is concerned, from a hot metallic instrument, a wooden spatula was advocated in the 1940s. It was in the 1970s when low-rotation micromotor were proposed along with 18% HCl, hydrogen peroxide and ether. Abrasive agents were not introduced before 1982 when Pumice was coupled with 36% HCl.
Today, 37% phosphoric acid or 6% HCl is used along side an abrasive agent. The abrasive agent used is silica based. The granulations of the abrasive agent vary in size and are incorporated in a water soluble gel. These compounds are applied precisely by a rubber cup to a rotatory mandrel. Rubber dam application is recommended.
The number of applications of the microabrasive compounds can vary depending on the severity of staining of the enamel. The first step involves macroreduction of the enamel, wherein a fine-diamond bur is used to a remove the affected area. Microabrasive slurry can then be applied to remove the remaining stains and smoothen the enamel surface. This is known as the "Abrasive effect." Later, polishing is done with felt discs and polishing or fluoridated pastes. Many a times, microabrasion is coupled with bleaching for reducing the contrast between white spotted lesion and tooth surface. Bleaching is usually done with carbamide peroxide.
Indications for tooth enamel microabrasion
Tooth surface with stains or defects that are restricted only to enamel are the most common indications for microabrasion. Enamel microabrasion is effective in dental fluorosis cases where lesions have yellow or brown discolorations. Mineralised white stains following the completion of orthodontic treatment can be removed effectively by enamel microabrasion. Localized enamel hypoplasia when corrected with enamel microabrasion can reduce bacterial colonization on enamel surface.
Contraindications for enamel microabrasion procedure
Enamel microabrasion cannot be done in patients with incompetent lips. This is mainly because the teeth are always exposed to air and dehydrate more easily. The stained appearance of teeth become more evident in this condition and may lead to failure of microabrasion. Unerupted or partially erupted teeth make enamel microabrasion a difficult procedure. This is because rubber dam application becomes difficult. Discolorations that arise because of imperfections in dentin are not treated by microabrasion. Such discolorations can be seen in dentigerous imperfecta or tetracycline discolorations.
Long term success
Microabrasion does lead to a reduction of 25-200 micrometres of enamel, which is considered safe in clinical conditions. Such alterations in micromorphology of enamel suggests that microabrasion causes a smoother, denser, mineralised enamel layer. This also makes it difficult for pathogenic bacteria like Streptococcus Mutans to adhere to the tooth surface.
Hoeppner et al reported that enamel surface was more resistant to demineralization four months after microabrasion with phosphoric acid.nFurthermore, clinical results have shown that the permanent color modification of enamel achieved by microabrasion achieves an esthetic luster over time. Techniques like microabrasion-remineralization have been effective against moderate fluorosis. This is done by combining remineralizing agents like CPP-ACP with 37% phosphoric acid.
Some of the commercially available microabrasion products include Prema compound, Opalustre and Pumice. These products help in cementing enamel microabrasion as a premier treatment plan in the field of cosmetic dentistry.