The invention relates to a method and a device for studying the adherence of dental restoration materials to enamel and dentin. The claimed device comprises a laser excitation source (2) which emits a laser beam which is very precisely directed onto the sample to be investigated by means of an electrically-controlled mirror system (7), a selective voltmeter (3), which generates a reference signal for the intensity-modulated laser, an infrared chamber (4) which registers the thermal signal generated by the sample and has incorporated a synchronous detection module for receiving both the thermal signal and the reference signal transmitted by the selective voltmeter (3), which processes the received signals and generates some images of amplitude and phase corresponding to the excitation frequency, images which are afterwards displayed on a computer screen (5) wherefrom they can be exported for subsequent processing. The claimed method consists in using infrared synchronous detection thermography coupled with contour recognition image processing algorithms to emphasize the useful information in the defect area and remove noises, to finally obtain a binary image, namely a pixel matrix with values of 0 or 1 which delivers the particular signature of the surface defect.Invenţia se referă la o metodă şi la un dispozitiv pentru studiul adeziunii la smalţ şi dentină a materialelor de restaurare dentară. Dispozitivul conform invenţiei cuprinde: o sursă laser (2) de excitare, ce emite un fascicul laser care este dirijat foarte precis pe proba de investigat, cu ajutorul unui sistem de oglinzi (7) controlate electric, un voltmetru selectiv (3), care generează un semnal de referinţă pentru laserul modulat în intensitate, o cameră (4) în infraroşu, care înregistrează semnalul termic generat de probă, şi are încorporat un modul de detecţie sincronă, pentru recepţionarea atât a semnalului termic, cât şi a semnalului de referinţă transmis de voltmetrul selectiv (3), care prelucrează s