Published online Feb 26, 2020. doi: 10.12998/wjcc.v8.i4.743
Peer-review started: November 19, 2019
First decision: December 4, 2019
Revised: January 10, 2020
Accepted: January 11, 2020
Article in press: January 11, 2020
Published online: February 26, 2020
In Mexico, dental fluorosis is considered a common health issue, especially in desertic areas, due to the high mineral content in water from increasingly deeper underground wells. In the State of Chihuahua there is an increasing number of individuals affected by fluorotic enamel stains, which are conspicuous and affect socialization of young people, and the majority of young people have some degree of dental fluorosis. Our main objective is to help society through research and for that reason our efforts have been directed at trying to provide a safe and effective treatment for dental fluorosis. Despite conducting several clinical studies, we have not previously published our results. However, we believe that our experience could help improve or set new guidelines for the treatment of dental fluorosis.
One of the main problems of fluorosis treatment in children and adolescents is the selection of first-choice treatment, which often is restorative instead of whitening or microabrasion and later must be periodically changed. Thus, it is important to implement non-invasive treatment protocols for young individuals with stains which compromise their aesthetic appearance. On the other hand, there are many microabrasion techniques with variations in the materials and procedures used, which we could unify to achieve an ideal treatment, through research of these variables. One of the main motivations for this research was the differences observed between a manual technique and a mechanical technique; therefore, we decided to use a manual technique, improve it and then compare it against a technique using rotary instruments. Thus, the choice of technique could become clearer following improvement, which may involve the unification of criteria and techniques.
One of the main objectives of this study was to assess the effectiveness of the microabrasion technique by taking into account enamel loss caused by the technique against the benefit of stain removal. In addition, the variation in procedure time taking into account stain size was estimated. These variables were measured using simple techniques that can be carried out by any dentist, except for the assessment of treatment effectiveness, which was measured using initial and final images and specific software. Measurement of these variables can be performed in any dental microabrasion technique, and the outcome of several techniques can be compared. However, we believe that the manual microabrasion technique is less invasive than those techniques involving rotary instruments, which we attempted to show in this study.
Dental fluorosis is a line of research that we have developed for many years in the Autonomous University of Chihuahua. Before this study, we conducted other projects which showed the advantages and disadvantages of microabrasion. Through time we have experimented with different methodologies from patient selection, to the technique itself. We conducted a study comparing the manual and rotary techniques, where stain measurement and efficiency were carried out using geometric figures and determined the surface area using photographs with a ruler on the patient’s chin. Procedure time could be extended and it was especially difficult to measure using rotary instruments, as several applications were made and it was difficult to measure the total procedure time. It took some time to design the acrylic guide to measure enamel loss, as there were several orifices around the stain and we averaged the results. We soon realized that this method was not reliable and we changed and perfected the technique. We observed that when microabrasion was completed there were occasional diastemas in adjacent teeth and we decided to protect these teeth. We believe that we must continue to improve and propose alternatives for measurement, through our results and through publishing in order to receive expert opinions.
One of our main findings in this study is the effectiveness of this technique, which was on average 90% despite the stain size in the fluorotic enamel and variations in procedure time. We consider that it is a safe and minimally invasive treatment, as the manual technique provides greater control of enamel loss, which was shown to be within 250 μm; therefore, it is a safe and conservative treatment. Of the safety measures, procedure time is directly related to enamel loss in any microabrasion technique; therefore, it was limited to 6 min; in addition to this, in teeth where the stain was removed before this time, it could be reduced to 1.65 min.
The effectiveness of this technique was on average high at 90%; however, we did not observe statistical significance with respect to stain size, enamel loss and procedure time, but we did find an upward trend. Procedure time and enamel loss were lower in small stains, but were not significantly different in middle-sized and large stains. The highest enamel loss occurred in large enamel stains, or those over 40% of the vestibular face, but without statistical significance. Enamel loss was statistically significant when the procedure time was more than 4 min, with an average of 234 μm; however, the minimum and maximum values reached 100 and 450 μm, for a procedure time under and over 4 min, respectively. Controlling the procedure time to under 6 min using 16% HCL and the manual technique resulted in enamel loss within the acceptable average range. Reduction in the size of the enamel stain caused by fluorosis after microabrasion was related to the tooth surface percentage covered by the stain.
Mechanical microabrasion techniques using abrasives result in greater loss of fluorotic enamel than manual microabrasion techniques without abrasives. The effectiveness of the microabrasion technique using software is different than the effectiveness perceived by the patient and their relatives.