Dental apparatus and method of utilizing the same

A method for detecting dental plaque at a site on a tooth, comprising:

• emitting a first modulated excitation calibration signal from a dental apparatus configured to detect the presence of dental plaque;
• comparing a difference between a detected modulated excitation calibration signal fluorescence and a second reference value with a difference between the second reference signal and a first reference signal such that if the difference between the detected modulated fluorescence signal and the second reference signal is greater than the difference between the first reference value and the second reference value then the first reference value is updated;
• emitting a second modulated excitation signal inside a mouth of a patient;
• detecting an emitted fluorescence light of the second modulated excitation signal;
• and
• analyzing at least one property of the emitted fluorescence light of the second excitation signal to detect the presence of dental plaque.