3.5 Criteria and Methods for Selecting Teeth to Be Sealed

A variety of tools are available that can help oral health professionals in school-based dental sealant programs determine which teeth are good candidates for sealant placement. All the criteria and methods discussed in this module are primarily focused on identifying cavitated lesions in the pits and fissures of teeth (including occlusal surfaces, buccal pits, and lingual grooves), to determine whether to place sealants on teeth in school-based dental sealant programs. To effectively place a resin-based sealant, the tooth surface must be kept dry. According to ADA, resin-based sealant materials are superior to glass ionomer materials.4

Thus, the area to be sealed must have erupted (i.e., it cannot be covered by soft tissue). Surfaces that cannot be isolated and kept dry should not be sealed. Moisture-tolerant (hydrophilic) sealants lack the extensive evidence demonstrating effectiveness available for hydrophobic sealants such as resin sealants, which are not moisture tolerant.3 In some instances, it may be possible to seal the occlusal surface of a tooth that has partially erupted, but it may not be possible to seal the buccal pit or lingual groove, because the tooth has not erupted sufficiently. These other surfaces may need to be sealed at a follow-up evaluation.

Visual Criteria

  • ADA and CDC both support the use of visual assessment as the method of choice to decide whether dental sealants should be placed.4
  • Visual assessment alone is appropriate and sufficient to detect surface cavitation and/or other signs of dentinal involvement before sealant placement.
  • Before being assessed, the tooth surface should be cleaned with a toothbrush to remove debris and plaque.
  • To detect large cavitated lesions in which the dentin is clinically visible, the tooth surface does not need to be dried. However, to detect smaller surface breaks, the tooth should be dried with compressed air, when available. If sound surfaces or early non-cavitated lesions are to be detected (which is not necessary in school-based dental sealant programs to determine which teeth need sealants) then the tooth needs to be thoroughly dried with compressed air for at least 5 seconds.
  • Non-cavitated lesions in pits and fissures may appear as a white, yellow, or brown discoloration (or a combination of these colors), which may be limited to the confines of the pits and fissures or may extend from the pit-and-fissure system. Very early lesions are visible only after air drying. More advanced lesions are visible when the tooth is wet or dry.
  • Non-cavitated and cavitated lesions with extensive dentinal involvement also may be accompanied by an underlying gray shadow. The shadow is often easier to see when the tooth is wet.
  • A cavitated lesion appears as a discontinuity or break in the surface owing to loss of tooth structure. The break can be confined to the enamel or may expose dentin to the oral cavity.
  • A child who received a dental sealant at a school-based dental sealant program on a non-cavitated lesion that extended into the dentin may subsequently have the lesion identified with X-rays taken in a dental office. If that situation is brought to the attention of the school-based dental sealant program, both the program and the dental staff must understand that, based on the scientific literature, there is no reason to believe that the sealant placement caused harm. In fact, the sealant may have stopped the lesion from progressing before the dentist could assess the child.6