Bactericidal effect of lasers in dentistry includes which of the following outcomes?

• A. Promotes bacterial growth
• B. No change to bacteria
• C. Bactericidal effects sterilizes the area
• D. Causes tissue necrosis

Answer: (C)

The bactericidal effect of lasers in dentistry comes from delivering energy that kills bacteria, usually by heating or via reactive species generated during treatment. This energy disrupts bacterial cells, reducing or eliminating their viability in the treated area. In practice, that means the laser can significantly lower the microbial load in procedures like root canal disinfection or periodontal pocket decontamination, and under favorable conditions may sterilize the local environment. The other options don’t describe the intended outcome: lasers do not promote bacterial growth or leave them unchanged, and while excessive energy can cause tissue damage, that necrosis is not the desired bactericidal outcome.