The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 06, 1989
Filed:
Feb. 25, 1987
G Maret Maxwell, Wheaton, MD (US);
Richard L Webber, Myersville, MD (US);
Abstract
An optical technique and device for assessing tooth vitality, involving the use of trans-illumination to detect differentially the relative absence of light absorbed by hemoglobin in circulating blood inside a healthy tooth. White light received from an illuminated healthy tooth is relatively devoid of intensity at a wavelength characteristic of absorption by hemoglobin, when compared with light following the same path in the tooth but of a longer wavelength, by taking the ratio of intensities of the two wavelengths the light of one wavelength is relatively more absorbed by hemoglobin or oxyhemoglobin than the other, indicating the relative amount of blood or oxygen in the blood present in the tooth at the time of the measurement. A broad-spectrum light source is rigidly coupled to a split-beam, differentially-filtered photometer incorporating relatively narrow band filters. Vitality is assessed from the ratio of the scattered light at the two wavelengths, and in change of this ratio overtime.