The importance of laser-induced breakdown spectroscopy (LIBS) for the rapid identification of teeth affected by caries has been demonstrated. The major and minor elemental constituents of teeth samples were analyzed using the prominent transitions of the atomic lines present in the sample. The elements detected in the tooth sample were: calcium, magnesium, copper, zinc, strontium, titanium, carbon, phosphorous, hydrogen, oxygen, sodium, and potassium. The results revealed that the caries-affected part contained a less amount of calcium and phosphorous in comparison to the healthy part of the tooth sample, whereas higher content of magnesium, copper, zinc, strontium, carbon, sodium, and potassium were present in the caries-affected part. For the first time, we have observed that hydrogen and oxygen were less in healthy parts compared to the caries-affected part of the tooth sample. The density of calcium and phosphorous, which are the main matrix of teeth, was less in the caries-affected part than in the healthy part. The variation in densities of the trace constituents like magnesium and carbon, etc., in caries and healthy parts of the tooth sample are also discussed. The presence of different metal elements in healthy and caries-affected parts of the tooth samples and the possible role of different metal elements in the formation of caries have been discussed.