Sealant on a partially erupted molar
A 9-year-old boy presents for sealants on the first permanent molars. Tooth 16 (maxillary right first molar) is fully erupted with deep occlusal pits. Tooth 36 (mandibular left first molar) is partially erupted; the distal marginal ridge is covered by tissue and the field is difficult to keep dry. Tooth 46 has a small, cavitated lesion in a pit that the dentist has diagnosed as dentinal caries. The boy is cooperative but has a strong tongue thrust and saliva is pooling on the mandibular left side. The dentist has asked you to place sealants on the teeth that are appropriate and to report anything that should not be sealed.
1. Which teeth should receive sealants today, and which should not? Explain your reasoning for each.
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Seal tooth 16 if the field can be isolated and the pits are caries-free after cleaning. Do not seal tooth 46: a cavitated lesion diagnosed as dentinal caries requires restorative treatment, and sealing over active caries would trap bacteria and allow progression. Tooth 36 should not be sealed today because it is partially erupted and cannot be isolated reliably; moisture contamination prevents adequate bonding and retention, and tissue coverage prevents complete coverage of the occlusal surface. Report the findings on 46 to the dentist and defer 36 until it is fully erupted and isolatable, then reassess. Sealants are preventive for sound, susceptible pits and fissures, not a substitute for caries treatment.
2. Describe the sequence you would use to place the sealant on tooth 16, including isolation and moisture control.
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Isolate the tooth, ideally with a dental dam or, if the dentist approves, with cotton rolls, a dry-angle device, and high-volume evacuation. Clean the occlusal surface with a bristle brush and pumice or an air-abrasion device per office protocol, then rinse and dry thoroughly. Etch the enamel with phosphoric acid gel according to the manufacturer's time, usually about 15 to 30 seconds for permanent enamel, keeping the field dry. Rinse and dry until the enamel appears frosty white; if it does not, re-etch. Apply the bonding agent if the system requires it and light-cure per instructions. Place the sealant into the pits and fissures without overfilling or leaving voids, and use an explorer to check that no air bubbles are trapped. Light-cure, then check retention with an explorer and adjust occlusion if the sealant is high. Re-isolate and re-dry if contamination occurs at any step, because saliva contamination after etching will cause failure.
3. How would you manage the tongue thrust and saliva during the procedure, and what would you tell the parent afterward?
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Use a dental dam if the tooth can be clamped safely, since it is the most reliable way to control moisture and protect the tongue. If a dam is not used, place cotton rolls buccally and lingually, use a dry-angle device, and have the assistant retract the tongue with a mirror or a tongue retractor while suctioning continuously. Ask the boy to swallow before starting and to keep his tongue still. If saliva contaminates the etched surface, re-etch. Afterward, tell the parent that the sealant is a preventive coating, not a guarantee against decay, and that the tooth must still be checked at recalls because sealants can chip or wear. Advise avoiding hard or sticky foods that could fracture the sealant, and report any high bite or loss of the sealant. Note that tooth 36 will be reassessed when fully erupted, and that tooth 46 needs restorative care.