A method for localizing gingival inflammation using an oral care device, comprising: (i) simultaneously emitting (520) light by a plurality of light sources (48) of the oral care device, wherein at least some of the plurality of light sources emit light of different wavelengths to result in a plurality of emitted light wavelengths, wherein each of the different wavelengths is modulated with a distinct code； (ii) obtaining (530), by a light detector (40) of the oral care device, reflectance measurements from a location within the user's mouth to generate reflectance data for the location； (iii) demodulating (540), by a controller (30) of the oral care device, the obtained reflectance data； and (iv) determining (560), by the controller using the demodulated reflectance data, whether gingiva at the location is inflamed.
