Bonnie Rae DMD, Bonnie Rae DDS, Bonnie Rae Dentist

Dr. Bonnie Rae back with you, this week to discuss cavity prevention.  Cavity Prevention can be done at different levels, and it’s their sum the one responsible for the reduction of the cavities index, at a personal level as well as a community level. Below, Dr. Bonniem will cover the most efficient preventive methods, Fluorine Use and Fissure Sealing.

Dr. Bonnie also recommends both a balanced diet and plaque control in the prevention of cavities and many other buccal diseases.

FLUORINE

Fluorine is an element from the Calcium Fluoride group, either as a component of fluorpatite or criolita.

It is found in water at very diverse levels of concentration, some water have a low level of concentration, others have optimum levels and others excessive levels.

The optimum level of fluorine in drinkable water should be of 1 mg/l, expressed in ppm (parts per million). Water with levels below 0,7 ppm, provide little fluorine to the teeth. Water between 0.7 and 1.2 ppm, provide sufficient fluorine and water with more than 2 or 3 ppm can produce an excessive accumulation of fluorine in the teeth and provoke intrinsic colorations, called DENTAL FLOUROSIS.

Fluorine is present in a variety of foods; it is abundant in tea, and decreasingly present in tomatoes, beans, lentils, cherries and potatoes. In animals, it is found in sardines, mackerel, veal liver, and fresh fish.

Fluorine is absorbed by the stomach and thin intestines, travels through the blood and accumulates in bones, teeth and secondly in soft tissues, once metabolized it is eliminated by renal routes and in a smaller proportions through bowel movement and sweat.

ACTION YOU CAN TAKE

For the cavity process not to begin, the teeth’s enamel resistance level must be increased, we have already mentioned that it starts to dissolve at a pH under 5,5.

The teeth’s enamel is the hardest tissue in the human body, and it is formed, among others, by hydroxyapatite, composed by calcium ions, phosphate and hidroxides.

An acid attack on the hydroxyapatite makes it desminiralize, it looses its crystal structure and if there is not another acid attack, there is a certain capability for remineralization, but in view of new acid attacks this capability can be lost and become irreversible and from here on the destructive process starts.

Fluorine replaces hidroxides ions (OH) from hydroxyapatite, and transforms it into fluorpatite, which is more stable and less dissolvable against acid attacks.

Fluoropatite dissolves at a pH level of 4.5, a point below hydroxyapatite.

Fluorine also has an effect on bacterial plate; it partially inhibits acid production by the plate’s bacteria, while having a toxic action on them therefore preventing bacteria absorbance by the film acquired.

FLUORINE APPLICATION AS A PREVENTIVE SYSTEM AGAINST CAVITIES

We have seen that fluorine’s principal action is to increase the enamels resistance by changing hydroxyapatite into fluorpatite.

Fluorine reaches the teeth through different channels:

• Topic channels

Systemic channels are based on the intake of a certain amount of fluorine, and by plasmatic routes it arrives to the teeth and transforms the enamel’s hydroxyapatite in fluorpatite.

This occurs during the formation process of our dental pieces, in the pre and post eruptive phases.

This is why fluorine intake is important, keeping in mind the different benefits we receive as to not exceed the limit which might lead into a fluorosis. If drinkable water contains a fluorine concentration of less than 0.7 ppm, this suggests that they are poor waters and therefore the intake of a fluorine supplement is recommended so the dental formation can be based on fluorpatite.

When drinkable water contains a level above 0.7 ppm, supplementary intakes are not necessary, the dental pieces will receive enough fluorine to form fluorpatite. Water with levels of 2 or 3 ppm, during the teeth’s formative periods, is not recommended since it might lead to fluorosis.

SYSTEMIC APPLICATION

Supplementary systemic benefits are achieved by the fluorine concentration on the water used by the individual. It is very important, if possible, to study the quantity of fluorine consumed by the patient, and the kind of water drank.

The patient’s age must be then associated to the fluorine concentration levels of the water consumed.

The ADA (American Dental Association), as time has advnced, has recommended a decease on the contributions of systemic fluorine, due to the great increase on the benefits of topic fluorine, the last recommendation dates back to 1994, being the doses much less than the ones recommended before in charts also published by the ADA.

The last charts relates fluorine concentration in water, with the child’s age and the dose of systemic supplement, in milligrams, needed.

Nowadays you can easily find in the market salt and flour enriched with fluorine.

A lot has been said on the importance of fluorine intake during pregnancy to increase the concentration levels during intra uterus dental formation.

Even though some authors have recommend the intake of a fluorine supplement from the 4th month of pregnancy, today there is no evidence to prove that fluorine goes through the placenta and therefore the use of systemic fluorine during pregnancy is not recommended.

The importance of systemic fluorine use has decreased, instead topic application have proven to radically and considerably decrease the appearance of cavities.

Based on our experience, in Catalonia the number of cavities reported in the 1970’s was greater than those in the following decades, in both public and private areas, using a program that prescribed the use of mouthwash once a week.

The objective of topic application is to form fluorpatite in the post eruptive period.

This application can be done using different methods:

There are two ways of applying topic fluorine:

At the patient’s house toothpastes and mouthwashes are used.

TOOTHPASTES

Toothpastes with higher levels of fluorine are widely used, it is the easiest way of self applying fluorine, since every time a person brushes there is a fluorine application.

The concentration of fluorine varies depending on the different brands available in the market today. The higher the concentration the better the topic effect will be and therefore the amount of fluorine absorbed by the dental enamel is higher. Laboratories produce toothpastes with concentrations of 1000 – 1100 ppm, even though there are some with higher levels.

Different Fluorine Toothpastes

The most commonly used fluorine components are: sodium fluoride or sodium monofluorphosfate (MFP). Others are nicametanol fluorhydrate (Fluorinol).

The problem with fluorine toothpastes is that if wrongly used they can lead to fluorosis.

In children below 6 years old, one must be careful since they can swallow the toothpaste and then it acts as a systemic fluorine, reaching excessive quantities of fluorine intake.

In small children the use of toothpastes with lower levels of fluorine is recommended and also the use of smaller amounts in each brushing to avoid, if swallowed, the appearance of fluorosis.

COLLUTORIES (MOUTHWASH)

We have mentioned earlier that collotories have helped in decreasing the number of cavities, they are easy to use and in this chapter we will make reference to those with low concentrations of fluorine, since these are the ones used by the patient in the privacy of his house.

According to the fluorine concentration level, mouthwash’s can be used daily or once a week. The ones for daily use have a concentration of 0,05% of flourine and the ones for weekly use have a concentration of 0,2%.

The teeth are rinsed for a minute and after the apllication the patient must be 30 minutes without drinking or eating, this is why the nightly application is recommneded, using the mouthwash before going to bed.

Collutories are to be used with patients older than 6 years old, since children under this age have little control and tend to swallow the liquid, leading to a fluorosis by the excess of flourine through sistemic channels.

FLUORINE APPLICATION AT A DENTAL CLINIC

At a proffessional level, flourine can be applied using different methods:

High concentration collutories are not commonly used since the other methods have proven to be more effective, but solutions of Sodim Fluoride at 2%, Pewter Floururo at 8% and Fluorphosphate Acid (PFA) solutions can be used.

GELS

This is the most commonly used method in dental clinics for applying topic fluorine.

Gels with Phosphrtic fluorine at 1,23% are used and currently gels with Sodium fluorine at 2% are also used. The advantage of using gels is that they contain lower acidity levels and do not alter, as much, the composite restaurations and ceramics that the patient might have.

Disposable trays are filled with gel and placed, the two arches at the same time, for 4 minutes.

Avoid rinsing, but the patient must spit out the excess gel to avoid swallowing it.

The trays are filled with at least 2,5 ml of gel and a dental aspirator must be placed so that the patient does not swall the salive mixed with gel.

VARNISH

Varnishes are used in dental clinics, the advantage they provide is that the fluorine applied, due to the lacquer support, remains in contact with the teeth for longer periods of time, therefore allowing the formation of fluorpatite.

It is recommended not to drink anything for 30 minutes, and even not to brush for 24 hours as to not eliminate it.

The patient might notice, in the hours following the application, the loosing of the fluorine supportive adherent layer.

Varnishes are advised in children younger than 6 years old, since they can swallow the gels but with this method this risk is not present. It is also indicated in patients that can not withstand, due to nauseas, the gel trays.

They are also recommended for mentally challanged pateints and in adults with dental sensibility.

FISSURE SEALING

This a very effective preventive method, it is done in dental clinics and it consists in applying a sealing material in the dental fossa and fissure on the occlusal sides of the molars and premolars, with the intention of avoiding the introduction of baterial plaque in them and therefore preventing the beginning of dental cavities.

The depth of the fosses and fissures vary anatomacly from person to person, therefore the deeper they are, the higher the quantity of plaque retained and greater the posibility of cavity formation. The different sistems of fluorzation do not benefit the enamel on this fosses, making them more vulnerable to acids.

Directions:

Sealling is prescribed in all recently erupted dental pieces with an occlusal side, and mainly in patients with a history of cavities in temporary dental pieces and with a family predisposition to cavities.

It is prescribed when the depth of the fosses and fissueres is excesive.

Contraindication:

In cases with multiple active cavities.

In patients lacking hygiene education and, generally, in poor cooperative patients.

Advantages and Inconveniences:

Sealing complements aother preventive methods (dentalk hygiene, topic and sistemic fluorization, diet control).

This is a very simple treatment, comfortable, it is not bloody, and there is no harm on dental tissue while applying the sealer.

The sealer can also inactivate an inicial cavity.

The main inconvinient is that the sealer can detach and it will have to be replaced. The attachment is done using engraving acid (orthophosphoric acid), but it is still considered a limited retention, even though, in general, they can last years.

Application Technique:

It is necessary to use a good technique, since part of the durability of the sealer depends on it.

Firstly, the plaque on the tooth’s surface has to be eliminated, for this you can apply abrassive pastes or fluorine- free toothpastes using a rotatory toothbrush or rubber cups.

In a tooth free of plaque the sealer adheres much better. Then, the dental piece to be worked on, must be isolated from the rest of the buccal cavity, since the salivary contamination must be avoided and in doing so there is a better retention of the sealer.

The ideal way of isolating the dental piece would be using a rubber dam, but this requires to anesthetize the patient in order to place the clamp, that is why it is better and therefore recommended, other ways of isolating the tooth like using cotton rolls, aspirator and separating the tongue using a dental mirror.

An engraving is made using orthophosphoric acid at 37%, the gel form can be used, even though the watery solution is also an alternative.

The engraving must be generous nad afeter 1-2 minutes have elapsed the dental pieces is rinsed abundantly during 15-20 seconds, to eliminate the acid remaining in the tooth.

After this, the dental piece is dried, if the typical mate or chalk white color of the dental piece is observed, then the engraving has been succesfull.

The sealer is later apllied with a brush, a dispensor or any other instrument that carries the sealing liquid to the fosses, it is very important to try and eliminate all the air bubbles that the sealer may have, since they can debilitate the sealer.

The sealer can be self-curing or photo-curing. The most commonly used is photo-curing, curing the sealer by means of applying halogenous light.

Since the fosses, fissures and grooves are places of bite support, the bite must be examined using articulating paper, to avoid prematuring central bite. In case that they are evident they must be eliminating using a simple steel bur in the exceeding material.