1. Field of the Invention
This invention is in the field of dental tools.
2. Description of the Prior Art
The traditional method of creating a replica tooth is to apply a pliable molding material around the tooth to be replaced with a replica then being created by the cavity formed in the molding material. More recent dental restoration technology utilizes an infrared camera. A white reflective powder comprised of titanium dioxide and talc is applied to the whole tooth creating a uniform color on the tooth and providing a means whereby the infrared camera can photograph and digitize the old tooth. Prior to the powder being sprayed onto the tooth, the dentist prepares the tooth for the porcelain restoration by removing the silver fillings and any lingering decay. A hand held infrared camera is then used to provide an image of the tooth onto a video screen. The replica tooth is then designed through the use of a computer. Once the design of the replica tooth is completed, the dentist utilizes a milling machine for cutting the actual replica tooth from a ceramic block. Such a system is manufactured by Siemens Dental Products Division and distributed in the U.S. by the Patterson Dental Supply Company under the name CEREC 2.
The current technique of applying the reflective powder involves two containers connected together. One container is an aerosol of pressurized butane gas having an outlet directed through a second container of reflective powder which, in turn, has a flexible tube extending therefrom through which the powder is sprayed. Such an applicator is distributed by Vita Zahnfabrik H. Rauter Graph and Co., KG of Bad Sackingen, Germany.
Difficulties are encountered when applying the powder in remote locations of the mouth. The powder needs to be applied evenly. If the powder is too thick on one portion of the tooth then an inaccurate reading by the camera results since the camera reads the top surface of the powder. In many cases, the patient's cheek is in the proximity of the side of the tooth and thus must be forced outwardly therefrom in order for the powder to be sprayed evenly on the side of the tooth. The prior applicator includes an outlet stem which will bend when contacted against the cheek. I have therefore provided a rigid outlet tube to simultaneously force the cheek away from the tooth while powder is being sprayed by the tube onto the tooth. Thus, the dentist may with a single hand move the cheek away from the tooth while spraying the powder. Further, since the tooth has both vertical and horizontal surfaces and surfaces therebetween, the powder must be sprayed at various angles. As a result, the prior art powder applicator requires the dentist to tilt the container of powder in order to properly point the powder outlet towards the tooth surface. Once the powder container is tilted then it is possible for the powder to clump within the container and even clog the outlet. I have therefore designed a powder outlet tube rotatable about its longitudinal axis while allowing the powder container to remain in an upright position. The dentist's hand holding the powder applicator may also be used to rotate the powder outlet tube without necessitating use of the remaining hand of the dentist. The one hand adjustment of the nozzle makes application of powder more precise and more predictable. The powder spray can be directed with complete precision at no risk of clumping or uneven flow.
The powder outlet tube disclosed herein has a right angle bend on the distal end outlet allowing for more easy application of powder in remote areas of the mouth as compared to the prior device having a distal end extending at an angle from the longitudinal axis less than 90.degree.. In an alternate embodiment, I have provided a valve on the powder container allowing the dentist to control the flow with the same hand holding the container allowing for accurate powder application.
I have disclosed my applicator in Disclosure Document No. 423313, filed Aug. 27, 1997 with the U.S. Patent and Trademark Office.