Decay is a multifactorial infective degenerative disease of hard dental tissues, caused by Streptococcus mutans and Lactobacillus forming the bacterial biofilm of teeth surfaces. Decays generally evolve in fissures and pits of secondary molars. Pits and fissure sealants prevent decays if performed in two years from eruption. Ozone has bactericidal effect and remineralizing capacity on enamel.

The aim of this study is to assess the effectiveness of ozone application before sealants in increasing their duration in time.

Inclusion Criteria:

• first or second secondary molars to be sealed
• possibility to isolate with rubber dam both the teeth involved
• no clear signs of pigmentations
• good general health

Exclusion Criteria:

• latex allergy
• epilepsy or other severe neurological pathologies
• psychiatric disease
• excessive sensibility to electrical current
• severe asthma
• enamel disorders, such as amelogenesis imperfect, white spots, fluorosis or Molar Incisors Hypomineralization

Data collected during the study will be available from the Study Director on reasonable request after evaluation of a protocol approved by an Ethical Committee

After publication of data on peer reviewed journals

Data collected during the study will be available from the Study Director on reasonable request after evaluation of a protocol approved by an Ethical Committee