2. CAVITY PREPARATION
âa surgical procedure that removes caries
and excises the tooth tissue in order to
develop the mortise form that will
support and retain the restorative
materialâ
âthe orderly operating procedure required
to establish in a tooth the
biomechanically acceptable form
necessary to receive and retain a
restorationâ
3. COMPONENTS
Cavity
Wall
one of theenclosing sides of a
prepared cavity
Axial
Wall
Wall near thepulp and parallel
to the long axis of thetooth
Pulpal
Wall
Wall near thepulp and
perpendicular to the long axis
of the tooth
Line
Angle
Angleformed bythe junctionof two
walls along a line
Cavo-
surface
Margin
Anglein a prepared cavity formed by thejunction
of the cavitywall and the external tooth surface
Point
Angle
Angleformed by thejunctionof three
walls at a commonpoint
Undercut
Portion of the prepared cavity
confined by walls that converge
toward the surface
Retention
Groove
A linearchannelwithin a
cavity preparation
DovetailA widened orfanned out portion of a
prepared cavity
5. OUTLINE FORM
âThe shapeof the area of the tooth surface INCLUDED WITHIN THE
CAVOSURFACEMARGINSof theprepared cavityâ
âThe locations that the PERIPHERIES of the completed tooth preparation
WILLOCCUPYontoothsurfaceâ
âThe PERIMETER of tooth preparation in width, length and depth
dimensionsâ
6. THE OUTLINE FORM
Factors to be considered
Areas to be Included
1. Access tothelesion
2. Extentofthe lesion
3. Extentofthe caries-
susceptible toothsurface
area
4. Locationandextentof
developmental grooves
5. Therestorativematerialto
beused
6. Estheticfactors
7. Functionalrequirements
ofthe restoration
1. Areaof thecariouslesion
2. The adjacentdeep, non-
coalesced enamel defects
3. All undermined,
unsupportedenamel
7. RESISTANCE FORM
âThe shape given to the preparation that enables the restoration and the
remainingtoothstructure TOWITHSTANDMASTICATORY STRESSâ
âThe shape given to the preparation TO PREVENT FRACTURE of either
therestoration or toothduring insertion of thematerial orduring functionâ
9. RETENTION FORM
âThe shape of the internal aspect of a prepared cavity to PREVENT
DISPLACEMENT OF THE RESTORATIVEMATERIALâ
âThe form given to the tooth preparation, especially its detailed anatomy
and general shape, which enables the restoration, that it will accomodate,
TOAVOID BEINGDISLODGED BYMASTICATORYLOADINGâ
11. CONVENIENCE FORM
âThe shape or form of the cavity that ALLOWS ADEQUATE VISION,
ACCESSIBILITY, AND EASE OF INSTRUMENTATIONduring cavity
preparation as well asinsertion oftherestorative materialâ
âThat shape given to a tooth preparation or tooth modifications added to
the preparation or its instrumentation, which ENABLES THE
RESTORATIONTOBE COMPLETED CONVENIENTLYâ
12. THE CONVENIENCE FORM
Other Modes to Obtain
ConvenienceForm
1. Modificationsin tooth
preparation
2. Instrumentmodification
3. Separation
Ideally, a tooth preparation fulfilling all the requirements for
outline, resistance, and retention forms will be convenient to
instrumentation.
The most effective way is by proper control of the field of
operation and by adequate training and familiarity with the
armamentarium
13. CARIESREMOVAL
âThe MECHANICAL ELIMINATION OF CARIOUS DENTIN AND
DEBRISfromcavitypreparationsâ
âThe mechanical and/or chemical actions resulting in COMPLETE
ELIMINATION OF THE DISEASED, NONREPARABLE PORTIONS
OF DENTINâ
14. CARIES REMOVAL
Removal of Caries
Acutecariesâusing the
broadestdiscoid/spoon
excavator
Chroniccariesâusing large
roundbur preferablydull
REMOVAL OF DENTIN DEPENDS ON
TWO CONDITION:
AFFECTED DENTIN
âą doesnotcontain
microorganism
âącanberemineralizedby
restorativemeans
âąit isacceptedtoallow
affecteddentin toremain
in preparedtooth
INFECTEDDENTIN
âą containsmicroorganism
âącannotberemineralized
byrestorativemeans
âąit shouldberemoved
duringcavity preparation
15. FINISH OF THECAVITY
WALL
âInvolves REFINING OF CERTAIN AREAS OF THE CAVITY WALL: the dentin
portion, theenamelportion andthecavosurfacemarginâ
âThe âCONFIGURATIONâ OF THE ENAMEL WALLS is the shape, dimension,
location,andangulationof enamelcomponentsin afinaltoothpreparationâ
âTo PROVIDE THE BEST POSSIBLE MARGINAL SEAL AND MAXIMUM
STRENGTHtoboththetoothandtherestorative materialâ
16. Enamelwallmustrest uponsound dentin
FINISH OF THE CAVITY
WALL
Theenamel rodswhichform thecavosurface
anglemusthavetheir inner ends resting
on sounddentin
Therods whichform thecavosurfaceanglemustbe supported, or be
resting, onsound dentinandtheir outer ends mustbecovered by
therestorative material
Thecavosurfaceangle mustbeso trimmedor bevelled that
themarginswill not beexposed to injury incondensing the
restorative material againstit
17. CAVITY DEBRIDEMENT
âFinal step involving the use of explorer, air and water spray, and cotton
pellets toREMOVE DEBRIS FROMTHECAVITYPREPARATIONâ
âIt consists of FREEING ALL ANGLES AND SURFACES OF DEBRIS
andoftenincludes medicationandinsulationprocedures.