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Retention of titanium tetrafluoride (TiF4), used as fissure sealant on human deciduous molars.

When dental hard tissues are exposed to aqueous solutions of TiF4, an acid-resistant glaze forms on tooth surfaces. The aim of the present study was to examine the long-term retention of the glaze on TiF4-treated deciduous molars. The occlusal surfaces of four deciduous molars in each of seven children were treated with 4% TiF4 for 1 min. The sealed teeth were extracted after 1, 3, 6, or 12 months and examined with scanning electron microscopy. An extensive surface layer was present on all deciduous molars after 1 month. After 3 months the glaze appeared to be worn out on the cusp tips and in some areas on the cusp inclines. At 6 months the glaze was observed as small areas distributed over the cusp inclines with total coverage of the pits and fissures. After 1 year the presence of the glaze was limited to pits and fissures. Clinically, all fissures were caries-free by visual inspection at the end of the experimental period. The results indicate that the glaze formed after topical TiF4 application may be an effective way of sealing pits and fissures under clinical conditions.