4.3 Resin-Based Application Process

Following is a detailed explanation of the steps in the sealant-application process for resin-based dental sealants.6,11 No matter what type of sealant material is selected for use in a school-based dental sealant program, it is important to follow manufacturer instructions about the placement and polymerization of the sealant material.

Step 1: Tooth Preparation

Dental sealant material manufacturers recommend that tooth surfaces be cleaned before acid etching. Demonstrations have shown that sealant retention rates for teeth cleaned with a toothbrush are at least as high as for teeth cleaned with a handpiece.12

Step 2: Tooth Isolation

Effective saliva control can be achieved by positioning the child so that the teeth to be sealed are visible and accessible. If resin-based dental sealant material is used, meticulous isolation of tooth surfaces to avoid saliva contamination is a critical step in the sealant-application process. Use of a rubber dam is the ideal method for isolating teeth during sealant placement, but it is not always possible or appropriate for young children. Cotton rolls, dry field pads, dry field kits, and single tooth isolation are alternative options.

Any salivary contamination following acid etching will result in a weakened bond between the dental sealant and enamel and in lower retention rates. Sealant teams that effectively isolate half of a mouth at one time increase efficiency by reducing sealant-application time.

These steps should be followed to achieve proper isolation:

• Position the child’s head with the chin elevated, tilted away from the teeth to be sealed.
• Place cotton rolls buccally and lingually to the mandibular teeth to be sealed. Cotton roll holders can help the sealant team isolate half of a mouth rather than a quadrant.
• Place a buccal dry angle-type shield covering the parotid duct openings opposite the upper first permanent molars.
• Bend a dry angle-type shield at a right angle, place the shield between the tongue and the lingual cotton roll, and gently hold it in place to isolate the child’s tongue.
• If saliva saturation occurs, exchange wet barriers with dry ones or place dry barriers over moist ones that may be suctioned to remove excess saliva.
• Once the cotton rolls and barriers are in place, the teeth should be thoroughly dried.

Step 3: Acid Etching

• Etch the tooth surface with an acid etchant. Either liquid or gel etchant is acceptable.
• Apply the etchant so it is in contact with each tooth for at least 15–20 seconds. Extend the etchant at least 2 millimeters up the cuspal inclines, beyond the anticipated dental sealant margins. Include buccal pits and lingual fissures, if they are free of gingival contact.
• Avoid contact of etchant with skin or soft tissue. If contact inadvertently occurs, rinse the skin or tissue immediately with water. (For more information about preventing injury, see Injury Prevention.)
• If a tooth is partially erupted with grooves that are not accessible because they are partially covered with tissue, clinical staff should choose to seal the tooth with GIC sealant material, which does not require a totally dry surface for sealant placement.

Step 4: Rinsing and Drying

• Thoroughly rinse with water all etchant from tooth surfaces for at least 10–15 seconds, using the high-volume oral evacuator to help keep teeth dry. Either exchange wet cotton rolls for dry ones in a manner that does not contaminate etched surfaces with saliva, or place dry cotton rolls and/or dry angle-type shields over moist ones that shall be suctioned first to remove excess saliva. It is critical that saliva not come into contact with the prepared tooth surfaces during this step.
• Check air/water syringe by blowing a jet of air onto a glove or mirror. If small droplets are seen, adjust so that only air is expressed. Dry teeth until etched enamel appears frosty or chalky. If teeth do not take on a frosty or chalky appearance or are contaminated with saliva at any time, follow manufacturer instructions to re-etch, rinse, and dry.

Step 5: Sealant Application

• Since application steps will vary according to the type of dental sealant product selected, it is important to follow the manufacturer’s instructions for mixing the sealant material and applying the sealant to the tooth surface.
• Carefully flow sealant from one end of the fissure to the other to avoid air bubbles. If an air bubble does form, tease it out with a sterilized explorer tip, applicator tool, or micro-brush before curing.
• Do not overfill or underfill, and do not cover the marginal ridges with sealant material.
• If more than one tooth in a quadrant is being sealed, the most posterior tooth should be treated first, since maintaining dryness is more difficult in the back of the mouth.

Step 6: Curing

• For auto-polymerized sealants, allow sufficient time for dental sealants to cure, following the manufacturer’s instructions. The temperature of the unused sealant material in the plastic well in which the components were mixed will indicate sealant polymerization. The sealant will become warm during the polymerization reaction. Once the sealant cools down, clinical staff should be able to remove the hardened sealant from the mixing well, which indicates that the polymerization process is complete. The sealant on the tooth should be set by then, as well.
• For light-cured sealants, hold the light tip as close as possible to the tooth surface without touching the sealant material.
• Follow the manufacturer’s instructions for curing time (consider manufacturer recommendations to be the minimum amount of time acceptable for curing).
• If a light-cured sealant is used, ensure that proper wavelength and intensity for each type of curing light (according to the manufacturer’s instructions) are maintained by checking the light at least monthly for output and intensity with a meter designed for that purpose. Lights may be checked by a dental products supplier and repaired, if needed. Light meters are available for purchase through dental supply companies.

Step 7: Final Treatment of Surface

Immediately following dental sealant placement, while the teeth are still isolated, check dental sealants to:

• Ensure complete coverage. Examine the tooth to check that all possible pits and fissures have been sealed. If incomplete coverage is observed, add additional sealant material until coverage is complete.
• Check for bubbles or voids. Adding sealant material is necessary only in the unlikely event that the void or bubble exposes enamel. However, where a void has sealant material at its base, clinical staff frequently choose to add sealant material.

If additional material needs to be added and if salivary contamination has not occurred, add more sealant material, and cure. If the tooth is contaminated by saliva, re-etch the area for at least 10 seconds, rinse, dry, add more sealant material, and cure.

Step 8: Final Treatment of Surface

• To remove the oxygen-inhibited layer and reduce the possibility of unpolymerized monomer remaining on the tooth, wipe the surface of the tooth with a cotton roll or cotton applicator before having the child thoroughly rinse with water.