Air abrasion system for use in dental procedures

• US 6,106,288 A
• Filed: 10/17/1997
• Issued: 08/22/2000
• Est. Priority Date: 10/17/1997
• Status: Expired due to Fees

• Current Assignee: Gendex Corporation (Danaher Corporation)
• Original Assignee: DENTSPLY International Incorporated (Astrazeneca PLC)
• Inventors: Burroughs, Andrew C., Barry, Stephen D., Lake, John Andrew, Annett, David Howard Meldrum, Fraquelli, Roberto Giovanni, Chang, Shu Kun, Brassil, John Michael
• Primary Examiner(s): Wilson, John J.
• Application Number:
  US08/953,109
• Time in Patent Office: 1,040 Days
• Field of Search: 433/88, 451/90, 451/102
• US Class Current: 433/88
• CPC Class Codes: A61C 3/025 Instruments acting like a sandblast machine, e.g. for cleaning, polishing or cutting teeth

Abstract

A system for treating teeth and associated tooth structure using a pressurized air propellant mixed with abrasive material includes a manifold which defines air passages leading from the pressurized air source to dispensing chambers which hold the abrasive material. The manifold further provides a convenient structure for mounting a number of the system components. The manifold simplifies assembly of the system and improves the integrity of air passages within the system. The air abrasion system also has a mixing block and continuous purge feature which eliminate crosstalk and backflow problems when switching between abrasive materials. Evacuation apparatus incorporating a cyclone separator is integrally provided with the system which requires minimal regular maintenance and maximizes suction flow through the apparatus. A boost feature of the system is provided to selectively increase the ratio of abrasive material to air in an air-abrasive material mixture, thereby increasing the rate of tooth reduction, without requiring additional air pressure.

Claims

1. An abrasion system for delivering a mixture of pressurized gas and abrasive powder for use in dental procedures, the air abrasion system adapted to be attached to a pressurized gas source and a hose connected to a an abrasion hand piece, the system comprising the combination of:

a first dispensing chamber having a reservoir for holding a supply of abrasive powder, an inlet port adapted for fluid communication with the pressurized gas source, a powder outlet port, and motor means for advancing abrasive powder through the powder outlet port;

a mixing block having a first powder inlet port fluidly connected to the powder outlet port of the first dispensing chamber, and a purge port adapted for fluid connection to the pressurized gas source, wherein the first powder inlet port and purge port have associated therewith a first powder bore and purge bore, respectively, extending through the mixing bock and converging to form a common outlet connection adapted for releasable attachment to the hose;

wherein pressurized gas is supplied to the purge port for continuous flow through the mixing block, hose, and hand piece;

further comprising a second dispensing chamber having a reservoir for holding a supply of abrasive power, an inlet port adapted for fluid communication with the pressurized gas source, a powder outlet port, and motor means for advancing abrasive powder through the powder outlet port;

wherein the mixing block further includes a second powder inlet port fluidly connected to the powder outlet port of the second dispensing chamber, the first power inlet port having associated therewith a second powder bore extending through the mixing block and leading to the common outlet connection.

2. An abrasion system for delivering a mixture of pressurized gas and abrasive powder for use in dental procedures, the air abrasion system adapted to be attached to a pressurized gas source and a hose connected to a an abrasion hand piece, the system comprising the combination of:

a first dispensing chamber having a reservoir for holding a supply of abrasive powder, an inlet port adapted for fluid communication with the pressurized gas source, a powder outlet port, and motor means for advancing abrasive powder through the powder outlet port;

a mixing block having a first powder inlet port fluidly connected to the powder outlet port of the first dispensing chamber, and a purge port adapted for fluid connection to the pressurized gas source, wherein the first powder inlet port and purge port have associated therewith a first powder bore and purge bore, respectively, extending through the mixing bock and converging to form a common outlet connection adapted for releasable attachment to the hose;

wherein pressurized gas is supplied to the purge port for continuous flow through the mixing block, hose, and hand piece;

in which the mixing block further comprises a boost port with associated boost bore extending through the mixing block to converge with the first powder bore and purge bore, and a valve selectively controls delivery of the pressurized gas to the boost bore so that, when the valve is closed, the mixture of pressurized gas and abrasive powder has an increased proportion of abrasive powder.

3. The abrasive system of claim 2 in which the first powder bore extends linearly between the first powder inlet port and the outlet connection, and the boost bore intersects the first powder bore at an angle.

4. The abrasive system of claim 2 in which the first powder bore and purge bore have consistent diameters.

5. An abrasion system for delivering a mixture of pressurized gas and abrasive powder for use in dental procedures, the air abrasion system adapted to be attached to a pressurized air source and a hose connected to an abrasion hand piece, the system comprising the combination of:

a regulator having an air intake port sized for fluid connection to the pressurized air source, and first and second outlet ports;

a first dispensing chamber having a reservoir for holding a supply of abrasive powder, an inlet port fluidly connected to the first outlet port of the regulator by a chamber inlet air passage, a powder outlet port, and motor means for advancing abrasive material through the powder outlet port;

a first T-blocks attached to the first dispensing chamber and having a first inlet arm connected to the powder outlet port, a second inlet arm connected to a feed air passage branching from the chamber inlet air passage, and an outlet arm;

a mixing block having a first powder inlet port fluidly connected to the outlet arm of the first T-block by a first air-powder passage, a boost inlet port fluidly connected to a boost passage, a purge inlet port fluidly connected to the second outlet port of the regulator by a purge passage, and an outlet connection adapted to fit the hose leading to the abrasion hand piece; and

a manifold onto which the dispensing chamber is mounted, the manifold providing the chamber inlet air, feed air, and a portion of the boost and purge passages.

6. The abrasion system of claim 5 further comprising integral evacuation apparatus adapted for use with an evacuation hose with attached evacuation hand piece, the evacuation apparatus including a vacuum pump having an inlet, a filter connected to the inlet of the vacuum pump, a cyclone separator connected upstream of the filter, and an evacuation port sized for connection to the evacuation hose.

7. The abrasion system of claim 5 in which pressurized gas continuously passes through the purge passage.

8. The abrasion system of claim 5 in which the pressurized gas source is integrally provided with the system.

9. The abrasion system of claim 8 in which the pressurized gas source is an air compressor.

10. The abrasion system of claim 8 in which the pressurized gas source is a bottle of compressed CO₂.

11. The abrasion system of claim 5 in which a valve selectively controls delivery of the pressurized gas to the boost bore so that, when the valve is closed, the mixture of pressurized gas and abrasive powder has an increased proportion of abrasive powder.

12. The abrasion system of claim 5 in which the first dispensing chamber further comprises a vent port attached to a vent tube which discharges to atmosphere, a vent valve selectively controlling flow through the vent tube, the vent valve relieving gas pressure in the dispensing chambers when open.

13. The abrasion system of claim 12 further comprising a housing cover providing access to the dispensing chambers, wherein the vent valve is interlocked with the position of the housing cover so that, when the housing cover is open, the vent valve opens.