Conservative treatment of Fluorosis and post-orthodontic white spots
After the enthusiastic adoption of resin infiltration as a conservative treatment for conditions such as fluorosis and white spots, many dentists from around the world were disappointed by it only working “sometimes”. The indications for infiltration procedures and the clinical protocols are extremely important. Sometimes combining infiltration with bleaching can dramatically improve the outcome of the infiltration procedure, making it easier to complete the treatment successfully.
Bleaching should not be considered a vanity procedure anymore, but a conservative treatment, as it has clear actions in making white and amber spots disappear, among many other benefits.
White spots are common lesions of different etiology that haven’t been treated for ages, as, before the adhesive era, treatment of these lesions was extremely destructive (i.e. crowns). After a while, more conservative treatments came to the rescue, as mechanical macro-abrasion with burs, abrasive and acid micro-abrasion and composite resin restorations.
Recently, the ultraconservative treatment with chemical erosion, bleaching and resin infiltration has opened a window on the full, conservative treatment of these spots.
The young patient presented bad oral hygiene during the orthodontic treatment, specially in the cervical area and after removing the brackets we found demineralization of enamel caused by plaque accumulation. Buccal white spots are frequently associated with fixed orthodontic treatment. White spot prevalence of 50% (1), 60% (2) or even 97% (3) after removal of bonded or banded appliances. Post-orthodontic spots don’t always follow the contour of the orthodontic appliances, but many times the appliance prevents the patient from keeping a good access for hygiene routine to the proximal or cervical area while the other areas remain in good condition.
There is a range of treatment options for such white spots. Enhancing remineralization using fluoride or casein-phosphopeptide amorphous calcium phosphate has been shown to positively influence caries arrest. However, clinical studies could not prove a cosmetic improvement (12,13). Micro-abrasion or restorative techniques with composite are effective options but the best technique turned out to be resin infiltration, as it is associated to minimal loss of dental hard tissue.
Hyper-contrast of the initial picture is obtained by decreasing brightness and increasing contrast of the original picture; the extent of the lesion is thus better showed to help us determine the degree of the demineralization. This method was described by Salat et. Al. 2011 (2).
Isolation from first premolar to first premolar with well invaginated dental dam avoiding saliva infiltration. This field generally is more than enough, avoiding the use of clamps and ligatures.
Superficial demineralization by application of a 15% solution of hydrochloric acid, this technique opens up access to the hypo-mineralized lesion; is mandatory to respect the time with a chronometer. Wash generously during at least 20 seconds and dry with air.
Icon dry, which is 99,9% ethanol, is placed in order to get a preview of the situation. Manufacturer instructions suggest to place it 30 seconds, we highly recommend that, if you want to have a real preview, you leave abundant ethanol for 2 minutes to have an efficient penetration; then evaluate the aspect of the teeth. After evaluation there are 2 paths you can take: repeating the acid application or starting resin infiltration. In this case 2 acid rounds were made as the result at this stage was satisfactory.
Resin infiltrant (resin with low viscosity) penetrated into the lesion and occluded the porosities and masked the white lesions. You need to place the low viscosity resin, make sure that ambient lighting (including the unit light) is not strong. Leave the infiltration resin for 2-3 minutes. A common mistake at this stage is to hurry, causing an incomplete resin penetration.
Remove excess, and cure each tooth for 30 seconds. Apply glycerin and cure again. This step is completely optional, but what is not an option is to cure perfectly. We suggest 1 minute per tooth, at least.
Interproximal resin was removed with a polishing strip and cervical resin (which must be avoided by removing the raw resin) with the LM Arte Eccesso instrument.
Finishing and polishing steps are important for immediate appearance and for long term stability. In this picture, the goat brush is shown, but it is mandatory to pass a polishing rubber tip and then the brush with diamond paste. Generally this is the only way to get excellent gloss.
Just after polishing of the resin. Unpolished resin has a fair appearance in the immediate postoperative, but the resin on the surface remains raw due to the inhibited oxygen layer and it is extremely sensitive to the oral environment and staining. In a nutshell, it is contraindicated to leave infiltration resins unpolished as they will deteriorate in matter of weeks. Mechanical polishing will act partially on the resin and on the superficial portion of the enamel prisms, making it a hybrid surface with a very stable and performant shine.
White spots were transformed into “Type 2 M” intensive features (3). Both patient and dentist were very satisfied with only 2 erosion cycles, minimizing chair time and potential damage. Remember that doing more than 4 acidic erosion cycles leads to a dramatic increase in risk of tissue loss due to the chemical action and the need for composite to restore that damage.
An extension of the indications for the resin infiltration technique was proposed [Tirlet] to include fluorosis and traumatic lesions since, in these cases, as in early-stage caries, the lesion only involves the external third of the enamel [Denis]. When white spots involve deep enamel lesions, Molar Incisor Hypo-mineralization (MIH) or certain types of post-traumatic hypo-mineralization, or severe cases of fluorosis, resin infiltration is not effective. In the present case we can see a mild-moderate fluorosis camouflage of white spots.
Intraoral situation, the upper teeth are the most affected by the fluorosis spots.
Spots are aesthetically unpleasant. The patient came to our attention searching for a specific, non invasive treatment.
TIP: The best strategy features a first, mandatory home bleaching stage with 10% Carbamide Peroxide (White Dental Beauty) for 15 days. This might sound as a paradox, but many of the spots change, the color of the substrate whitens and the contrast between spot and tooth becomes is reduced. Spots are easier to infiltrate after bleaching and the reason is not clear yet.
Vita shade guide before treatment to have an approximate shade of the healthy tooth. and evaluate the shade before and after bleaching.
Vita shade guide after bleaching treatment. Note how many spots have drastically changed especially on tooth 21-22 that are more obious.
After bleaching we can see an increase in the overall brightness. White spots were dissimulated but, as we predicted, additional treatment is required.
Intraoral situation before acidic erosion.
Polarized image before etching/infiltration treatment. This kind of lighting gives us a clear view of each and every spot. Is the best method to evaluate the infiltration therapy.
Icon etch application for 2 minutes.
Icon dry application
Product is generously applied for 2 minutes to have a real preview as described in the previous case.
Low density resin is applied as well for 2-3 minutes without heavy ambient light sources. Note that an incomplete infiltration, due to insufficient time, may lead to failure of the whole infiltration treatment.
Teeth after infiltration treatment show no unpleasant white spot is left.
Mild fluorosis indication is generally very predictable with this kind of approach.
The patient is happy with the new brighter smile, and without spots.
Polarized image before.
Polarized image after treatment, showing how successful this therapy was.
Digital composition to show the dramatic effect of the before and after.
The resin infiltration technique is an effective treatment option in a large number of cases of post-orthodontic white spots and mild fluorosis.
A first clinical study demonstrated successful masking of post-orthodontic lesions (61% completely and 33% incompletely masked lesions) with infiltration treatment (Kim S. et al). In our experience even in the incompletely masked lesion the patients are satisfied with the results. After the success of the resin infiltration technique masking post-orthodontic white spots we decided to propose the technique to different origin white spots. So in our series of clinical cases it is seen that the resin infiltration makes it possible to treat the superficial enamel lesions effectively, whatever their etiology.
The role of whitening is very important since it helps vanishing effectively white spots and amber spots, making them more attackable by the resin infiltration technique.
First case performed by Dr. Elisa Oneto. Second case by Dr. Elisa Oneto and Dr. Anna Salat. Thanks to Dr. Elisa Oneto with whom it is always a pleasure to collaborate for an interdisciplinary approach.