Effects of Carbon Dioxide Lasers on Remineralizing Dental Caries

Objectives: To review the evidence regarding the effects of carbon dioxide (CO₂) lasers (λ=10,600 nm) on remineralizing dental caries.
Methods: This study performed a systematic search of the articles archived in the PubMed, Scopus and Web of Science databases. The keywords used to identify the relevant articles were ((CO₂ laser) OR (carbon dioxide laser)) AND ((dental caries) OR (tooth remineralization)). There was no publication-year limit, and the last search was made in December 2017. The titles and abstracts of the initially identified articles were screened. Duplicate records, non-English articles, reviews and irrelevant studies were removed. Full texts were retrieved for publications that studied effects of actions of CO₂ lasers on arresting dental caries.
Results: The search identified 495 potentially relevant publications. A total of 252 duplicate records were removed. Thirteen articles were included in this review. Three studies reported antibacterial properties of CO₂ laser. They found that growth of cariogenic bacteria, mainly Streptococcus mutans, was slower compared with non-irradiated ones. Four studies investigated the reduction of demineralization of enamel with cariogenic challenge. They found that CO₂ laser reduced carbonate content of mineralized tissues and increased microhardness of enamel. Eight studies used CO₂ laser associated with topical fluorides in remineralizing dental caries. Results of the synergistic effect of laser irradiation and fluoride application with regard to the inhibition of caries progression varied among these studies, while laser irradiation could enhance fluoride uptake to demineralized mineral tissues.
Conclusions: CO₂ laser irradiation increased acid-resistance of caries-like lesions and reduced the growth of cariogenic bacteria.