Category: Entertainment

Presentation Description

No description available.


Presentation Transcript




INTRODUCTION WHAT ARE THE USE OF INSTRUMENTS ? Instruments are essential - For preparation of cavity For removal and shaping of the tooth structure.

PowerPoint Presentation:

CLASSIFICATION Dr G.V.BLACK (FATHER OF CONSERVATIVE DENTISTRY) is credited with the first acceptable nomenclature and classification of hand instruments. Some instruments were individually handmade,variable in design,and difficult to use because of nature of handles and effective sterilization.


CLASSIFICATION Hand cutting instruments Cutting instruments Non-cutting instruments Cutting instruments Excavator Ordinary hatches Spoons Hoes Angle formers Chisels Straight, slightly curved chisels Enamel hatches Gingival margin trimmer Triangle chisel Other chisels Offset chisel Hoe chisel Other instruments Knives, files, scalers, carvers and discoid – cleoid Non-cutting instruments Mirrors, explorers, probes and amalgam condenser. Rotary instruments Dental burs Round bur Inverted bur Pear shape Straight fissure Tapered fissure End cutting

PowerPoint Presentation:

Description of hand instruments – hand instruments have three parts Handle Is used to hold the instrument Shank Is used to connect the handles to the working ends of instrument Is smooth, round and tapered Blade or nib Is used to design the angle of shank Instrument design Cutting edge is usually in the form of a bevel with different shape. Blade angle is an angle between the long axis of the blade and long axis of shaft. Cutting edge angle is an angle between the margins of the cutting edge and long axis of shaft


Dr G.V.BLACK classified instruments based on the number of shank angles - MONOANGLE-ONE BINANGLE-TWO TRIPLE ANGLE-THREE


HAND CUTTING INSTRUMENTS These are used to cut hard and soft tissues of mouth. EXCAVATORS– are used - For removal of caries . For the refinement of the internal parts of the preparation. TYPES— ORDINARY HATCHES– primarily used on – Anterior teeth for preparing retentive areas and sharpening internal line angles . SPOONS—are used for – Removal of caries and carving amalgam or direct wax patterns.


HOES EXCAVATOR –is used for- Planning tooth preparation walls and forming line angles. Commonly used in class III and V preparation for direct gold restoration . ANGLE FORMERS—are used for- Sharpening line angles and creating retentive features in dentin . Also may be used in placing a bevel on enamel margins .

PowerPoint Presentation:

CHISELS –are intended primarily for cutting enamel . TYPES— STRAIGHT ,SLIGHTLY CURVED CHISELS— It has straight shank and blade with bevel on only one side . Is used for cavity preparation. WEDELSTAEDT CHISEL—It has – Primary cutting edges in a plane ,perpendicular to the axis of the handle and may have either a distal or mesial bevel .

PowerPoint Presentation:

ENAMEL HATCHES –are Similar to ordinary hatches . Are used for cutting enamel and available as right and left types for use on opposite sides of preparation . GINGIVAL MARGIN TRIMMER—is designed to produce a proper bevel on gingival enamel margins of proximo-occlusal preparation. TRIANGLE CHIESELS—have three angles in shanks . Are used to flatten pulpal floor .


OTHER CUTTING INSTRUMENTS These are knives (gold,amalgam,finishing knives),files ,scalers ,carvers ,discoid –cleoid. KNIVES-are thin ,knife like blade i.e made in various size and shape. Are used for trimming excess restorative material on gingival ,facial or lingual margins of a proximal restoration . FILES—can be used – To trim excess restorative material. Particularly useful at gingival margins . SCALERS—are used – For removal of plaque .

PowerPoint Presentation:

Discoid – Cleoid – is mainly used – For carving occlusal anatomy in unset amalgam restorations

Some other techniques which are used with hand cutting instruments:

Some other techniques which are used with hand cutting instruments There are four grasps used with hand instruments Modified pen grasps Inverted pen grasps Palm and thumb Modified palm and thumb

PowerPoint Presentation:

Modified pen grasps The grasps that permits the greatest delicacy of touch is the modified pen grasps. It is similar to that used in holding a pen. Inverted pen grasps Is similar to pen grasps But the hand is rotated so that the palm is facing upwards Mainly used in upper teeth. Palm and thumb grasps Is similar to the method of holding a knife. It is mainly used on maxillary teeth particularly the right side, when working from the right rear chair position. Modified palm and thumb grasps Are used practically universally Mainly employed in the area of maxillary arch.

PowerPoint Presentation:

Rests Are used to steady the hand during operating procedures and these also act guards when thrust force is applied. Are used with modified pen and inverted pen grasps Guards Are hand instruments or other items such as interproximal wedges. Are used to protect soft tissue from contact with sharp cutting or abrasive instruments

Sharpening hand instruments:

Sharpening hand instruments Some other sharpening hand instruments and stationary sharpening stones are used in conservative dentistry. These are:- Arkansas stone Silicon carbide Aluminium oxide and diamond

PowerPoint Presentation:

Arkansas stone Is semitranslucent, white or gray in color and hard enough to sharpen steel Aluminum oxide Is increasingly used to manufacture sharpening stone Diamond Is the hardest available abrasive and is most effective for cutting and shaping hard materials.

Mechanical sharpeners :

Mechanical sharpeners As high speed rotary cutting instruments have been improved and their use has increased, the use of hand cutting instruments and need for resharpening has decreased. Rx HONING MACHINE is an example of mechanical sharpeners. This sharpener is also very versatile and can fill almost all instrument sharpening needs.

Hand piece sharpening stones:

Hand piece sharpening stones Ex. Mounted SiC and alluminum oxide stones for use with straight and angle hand pieces which are available in various sizes and shapes.


DESCRIPTION OF HAND INSTRUMENTS Hand instruments have three parts- HANDLE-is used to hold the instruments SHANK -is used to connect the handles to the working ends of instruments. It is smooth ,round and tapered. BLADE OR NIB –is used to design the angles of the shank.

PowerPoint Presentation:

INSTRUMENT DESIGN CUTTING EDGE-It is usually in the form of a bevel with different shapes . BLADE ANGE –It is an angle between the long axis of the blade and long axis of shaft . CUTTING EDGE ANGLE-It is an angle between the margins of the cutting edge and long axis of shaft.

PowerPoint Presentation:


authorStream Live Help