Periodontal probe

An apparatus for the force-controlled probing of a periodontal pocket in the oral cavity of a patient, which pocket has a bottom wall surface, which apparatus comprises in combination:

• (a) a periodontal probe having a tip at one end for contact with said bottom wall surface of said periodontal pocket, said probe also having an elongated body at the other end adapted to be mounted for slidable movement in a cylinder;
• (b) a cylinder adapted to be placed in said oral cavity, the other end of said probe being slidably mounted in the cylinder for reciprocal movement therein;
• (c) means to effect slidable reciprocal movement of said probe in said cylinder between a reference position and a depth-locating position;
• (d) end-point-determining means for determining the position of said probe tip on reaching said bottom wall surface of said periodontal pocket;
• and
• (e) depth-measuring means for determining the depth traveled by said probe on reaching said bottom wall surface, whereby the probe tip is moved in a controlled manner to a position adjacent to, or substantially in contact with, said bottom wall surface of said pocket, and wherein the depth of the pocket may be determined.

An apparatus for force-controlled probing of a periodontal pocket in the oral cavity of a patient, said pocket having a bottom wall surface, and for determining the depth of said pocket, which apparatus comprises:

• (a) a periodontal probe characterized by an elongated element having a tip at one end thereof for insertion into a periodontal pocket whose depth is to be determined, the tip end having a small gas passageway therein for the discharge of gas therethrough and from the tip of the probe, said elongated element also forming a piston having a body and a head;
• (b) a source of gas at a constant pressure;
• (c) means connecting the source of gas with the periodontal probe to permit the flow of gas from the gas source to the probe and the gas to be discharged from the probe tip;
• (d) flow-indicator means to measure the flow rate of the gas being discharged from the probe tip, whereby, on insertion of the probe tip into the periodontal pocket and as the probe tip approaches the bottom wall surface of the periodontal pocket, a rapid change in airflow measurement occurs, by means of which change in flow, the depth of the periodontal pocket may be determined, without penetration of the bottom wall surface of the periodontal pocket by the probe;
• (e) a first cylinder adapted to be placed in said cavity, the piston of said probe being slidably mounted in the cylinder for reciprocal movement therein, the piston head and the cylinder walls defining a first fluid reservoir therebetween for the storage of a first variable volume of essentially incompressible fluid;
• (f) a second piston and cylinder assembly, said second piston having a head and body and being slidably mounted within said second cylinder between a reference position and a locating position, the cylinder walls and piston head forming a second reservoir for the storage of a second variable volume of essentially incompressible fluid;
• (g) an essentially incompressible fluid initially stored within said first and second reservoirs;
• (h) connecting means to connect fluid in said first reservoir with fluid in said second reservoir and to allow the transport of fluid therebetween;
• (i) means to drive said second piston and cylinder assembly to effect pressurized fluid transport between said first and second reservoirs;
• and
• (j) depth-determining means to determine the distance traveled by said probe, said depth-determining means further comprising
• (i) a transducer means to convert the displacement of the second piston between the reference position and the locating position into an electrical signal proportional to the displacement,
• (ii) an amplifier electrically connected to the transducer means to amplify the electrical signal received from said transducer,
• (iii) a data converter electrically connected to the amplifier to convert the amplified electrical signal into digital form, and
• (iv) a display indicator electrically connected to the converter to display the digital signal from the data converter whereby the displacement of said second piston is shown as a visual display.

A removable, replaceable, periodontal probe for use with an hydraulic pressure system to probe a periodontal pocket and with a gas-flow system to determine the location of the bottom surface of the periodontal pocket, which probe comprises:

• (a) an elongated body portion having a tip at one end for insertion into said periodontal pocket, the tip end having a small passageway therein for the discharge of fluid therethrough, the body portion also having at or near the other end a connecting means for connection to a source of gas, so as to allow passage of gas through the body portion and from the tip upon connection to a gas-flow system;
• (b) a piston-shaped portion including a piston head and piston body connected to the body portion;
• and
• (c) a cylindrical housing portion surrounding said piston-shaped portion and permitting the piston-shaped portion to slide therein, the housing portion forming an hydraulic reservoir above the piston head, means for removably connecting said reservoir to the hydraulic-pressure system, whereby pressure from the pressure system upon connection results in movement of the piston-shaped portion and elongated body portion of the probe in the periodontal pocket, and whereby the location of the bottom surface of the pocket can be determined by observed changes in gas flow through the tip.

A method of measuring the depth of a periodontal pocket in the oral cavity of a patient, which method comprises:

• (a) securing in the patient's oral cavity a cylindrical instrument, which instrument includes a reciprocal, slidably moving, piston-shaped, periodontal probe having a tip and having a gas passageway through said instrument and out said tip;
• (b) applying force to said piston-shaped probe to move said probe into the periodontal pocket toward the bottom of the pocket;
• (c) passing a continuous flow of gas, at a predetermined flow rate, through the passageway of said probe during its movement into the pocket;
• (d) monitoring and measuring the gas flow to determine the point at which a rapid diminution or impediment in gas flow occurs, which serves as an indication of the bottom of the pocket;
• and
• (e) determining the distance traveled by said probe in its movement to the bottom of the pocket.