Systems and Methods for Spray Application of Glaze and Other Materials

Abstract

Methods and systems for automatically spraying a glaze solution onto a dental prosthesis are described. The automated spray glazing system includes: a first spray gun; a controller, and a gripper configured to hold the dental prosthesis and to rotate the dental prosthesis about an axis. The controller is configured to rotate the gripper and spray a glaze solution from the first spray gun using a glazing profile based at least in part on a type of the dental prosthesis. The glazing profile is selected such that a cross-sectional thickness of a resulting-glazed material of the dental prosthesis has an average thickness range between 15 to 63 μm and a standard deviation of less than 6 μm when measured at locations in an upper half of the dental prosthesis.

What is claimed is: 
     
         1 . A method for automatically applying glaze to a plurality of dental prostheses, the method comprising:
 securing a first dental prosthesis with a gripper; and
 automatically applying a glaze solution onto the first dental prosthesis, using a first spray gun, to produce a first glazed dental prosthesis; 
 repeating the above securing and automatically applying steps with each of a plurality of dental prostheses to obtain a plurality of glazed dental prostheses; 
 wherein a cross-section of each of the plurality of glazed dental prostheses has an average glaze thickness in a range between 15 to 63 μm and a standard deviation of less than 3 μm when thickness measurements are measured at locations in an upper half of each of the dental prostheses. 
   
     
     
         2 . The method of  claim 1 , wherein the glaze is automatically applied onto each of the plurality of dental prostheses in a manner such that each of the plurality of glazed dental prostheses is substantially free of internal cracks and surface pits. 
     
     
         3 . The method of  claim 1 , further comprising obtaining thickness measurements at three or more locations in the upper half of each of the plurality of dental prostheses, and at least one of the three or more locations is in an occlusal or incisal portion of each of the plurality of dental prostheses. 
     
     
         4 . The method of  claim 1 , wherein the average glaze thickness and the standard deviation are calculated from thickness measurements measured at three or more locations, a first location of the three or more locations is at a borderline between an occlusal portion and a middle portion of each of the plurality of dental prostheses, a second location of the three or more locations is above the first location, a third location of the three or more locations is below the first location. 
     
     
         5 . The method of  claim 1 , wherein the average thickness and the standard deviation are calculated from thickness measurements measured at three or more locations, a first location of the three or more locations is on a middle portion, and a second and third location is on an occlusal portion of each of the plurality of dental prostheses. 
     
     
         6 . The method of  claim 1 , wherein the upper half of each of the plurality of dental prostheses is from a midline portion of each of the plurality of dental prostheses to a start of an occlusal or incisal portion of each of the plurality of dental prostheses. 
     
     
         7 . The method of  claim 1 , further comprising the following steps performed for each of the plurality of dental prostheses:
 providing a second spray gun;   positioning the first and second spray guns to spray the glaze solution at the dental prosthesis from different angles; and   rotating the gripper in a first direction while the glaze solution is sprayed from the first spray gun; and   rotating the gripper in a second direction while the glaze solution is sprayed from the second spray gun.   
     
     
         8 . The method of  claim 7 , wherein the first and second spray guns are positioned at an angle between 45-180 degrees with respect to each other. 
     
     
         9 . The method of  claim 7 , further comprising:
 spraying the first spray gun at 7.125 inches away from the gripper; and   spraying the second spray gun at 6.275″ inches away from the gripper.   
     
     
         10 . A method for applying glaze to a plurality of dental prostheses, the method comprising:
 selecting a first glazing profile based on a type of a first dental prosthesis being secured in a gripper;   applying the glaze solution to the first dental prosthesis with a first spray gun using the selected glazing profile, repeating the above selecting and applying steps with each of a plurality of dental prostheses to obtain a plurality of glazed dental prostheses;   wherein each of the selected glazing profiles is configured to automatically glaze the selected dental prosthesis in a manner such that a cross-sectional thickness of a resulting glazed material of each of the plurality of dental prostheses has an average thickness greater than 12 μm and a standard deviation of less than 2.5 μm when thickness measurements are measured at locations in an upper half of each of the dental prostheses, wherein the upper half comprises a middle region and an occlusal or incisal region of each of the dental prostheses.   
     
     
         11 . The method of  claim 10 , wherein the glaze is automatically applied onto each of the dental prostheses in a manner such that each of the glazed dental prostheses is substantially free of internal cracks and surface pits. 
     
     
         12 . The method of  claim 10 , further comprising obtaining thickness measurements at three or more locations in the upper half of each of the dental prostheses, and at least one of the three or more locations is in an occlusal or incisal portion of each of the dental prostheses. 
     
     
         13 . The method of  claim 10 , further comprising the following steps performed for each of the plurality of dental prostheses:
 providing a second spray gun;   positioning the first and second spray guns to spray the glaze solution at the dental prosthesis from different angles; and   rotating the gripper in a first direction while the glaze solution is sprayed from the first spray gun; and   rotating the gripper in a second direction while the glaze solution is sprayed from the second spray gun.   
     
     
         14 . The method of  claim 13 , wherein the first and second spray guns are positioned at an angle between 45-180 degrees with respect to each other. 
     
     
         15 . The method of  claim 13 , further comprising:
 spraying the first spray gun at 7.125 inches away from the gripper; and spraying the second spray gun at 6.275″ inches away from the gripper.   
     
     
         16 . The method of  claim 10 , wherein the first glazing profile is configured create a glazed crown with a cross-sectional thickness variance of less than 6 μm. 
     
     
         17 . The method of  claim 10 , wherein the first glazing profile is further configured to:
 tilt a platform coupled to the gripper at a predetermined angle prior to applying the glaze solution to the first dental prosthesis; and   apply the glaze solution to the dental prosthesis using a second spray gun, wherein the first and second spray guns are positioned to spray the glaze solution at the dental prosthesis from different angles, wherein the glaze solution from the first spray gun is applied while the gripper is rotating in a first direction and the glaze solution from the second spray gun is applied while the gripper is rotating in a second direction.   
     
     
         18 . The method of  claim 17 , wherein the first and second spray guns are positioned at an angle between 45-180 degrees with respect to each other. 
     
     
         19 . The method of  claim 17 , further comprising:
 retracting a repositionable rod away from a nozzle of each the first and second spray guns after each glazing cycle; and   forcing pressurized air through the nozzle of the each of the first and second spray guns while the repositionable rod is retracted.   
     
     
         20 . The method of  claim 17 , further comprising:
 actuating a moveable piston of a GP block assembly to a first position to allow the glaze solution to be sprayed from the first spray gun, wherein the GP block assembly is fluidically coupled to the first spray gun;   actuating the moveable piston to a second position to block the glaze solution from entering a lumen of the first spray gun and to allow pressured air to push the glaze solution out of an intake-pipe and back to a glaze solution container, and wherein a cleaning solution is passed through a lumen and out of an exit nozzle of the first spray gun when the moveable piston is in the second position.