2. ā¢ Introduction
ā¢ Defenition
ā¢ Types
ā¢ Metal
ā¢ Esthetic
ā¢ Advantages
ā¢ Disadvantages
ā¢ Method of fabrication
3. ā¢When decay or fracture
incorporate areas of a tooth that
make amalgam or composite
restorations inadequate, such as
cuspal fracture or remaining
tooth structure that undermines
perimeter walls of a tooth, an
onlay might be indicated.
4. ā¢It is the type of restoration
which caps all the cusps of a
posterior tooth,can be
thoughtfully designed to
strengthena tooth that has
been weakened by caries or
previous restorative
experiences.
5. ā¢The onlay restoration is of
two types,
ā¢Cast metal onlay restorations.
ā¢Esthetic onlay reastorations.
6.
7. ā¢ Eliminates the fracture of tooth as in
cast inlay.
ā¢ More conservative than a full crown
restoration.
8. ā¢ Cuspal protection for all cusps is needed.
ā¢ Lenght : Width ratio is 2 : 1
ā¢ Need to cahange the occlusal relationship of the
maxillary and mandibula teeth.
ā¢ For abutment teeth in partial dentures.
ā¢ When excessive tooth wear of occlusal surfaces include
cuspal tips.
9. ā¢ Dovetailed internally
ā¢ Follow cuspal anatomy anatomy externally.
ā¢ Proximally ā Box shaped or cone shaped.
ā¢ Shoeing of the non ā functional cusp.
10. ā¢ OCCLUSO ā FACIO ā LINGUAL PORTION :
ā¢ Capped Cusp side :
ā¢ Margins located far gingivally.
ā¢ Involve 1/3rd or 1/4th of the facial or lingual walls.
ā¢ Gingivally :
ā¢ Include all the facial and lingual grooves
ā¢ Margins parallel to the cusp tips and crest of the adjacent
ridges.
ā¢ Shoed Side :
ā¢ Margins located just gingival to the tip and ridge crests of the
involved cusps.
ā¢ Away from occlusal contact.
11.
12. ā¢ Greater occlusal reduction for more bulk
ā¢ All circumferential tie constituents must be hollow ground.
ā¢ All cusps must be capped rather than shoed.
ā¢ Due to possibility of shortening the cavity walls maximum
parallelism should be strived for.
ā¢ Preparation should not feature any small, complicated
internal or external details.
ā¢ Concavity of hollow ground bevels must include enamel
and dentin.
13.
14. ā¢ Cuspal capping rather than shoeing.
ā¢ Counter bevel must extend more gingivally to provide
retention.
ā¢ Embracing angle for counter bevel must be more acute.
ā¢ There is more occlusal reduction for the table and
counter bevel to accommodate more bulk of cast ceramic
(1.5 ā 2 mm).
ā¢ The gingival, buccal and lingual walls , proximally should
be similar to those for inlay cast ceramics.
ā¢ Preparation must be deeper.
ā¢ No taper for walls, only parallelism must be achieved.
16. ā¢ Preparation walls should be 6-10Ā° occlusally divergent.
ā¢ Cuspal reduction of 1.5-2 mm in functional cusp and 1-
1.5 mm on non-functional cusp.
ā¢ All line angles and bevels are smoothly joined with no
interruption.
ā¢ Gingival, occlusal bevels and flares are prepared in a
manner such that a marginal cast gold metal of 40Ā° is
obtained.
17.
18. ā¢ The various other esthetic restorations for class I
and class II tooth preparations are
ā¢ Indirect Composite Inlay and Onlay
ā¢ Ceramic Inlay and Onlay
ā¢ CAD / CAM or CAD / CIM
(Computer Aided Designing/
Computer Aided Machining)
19. ā¢ Esthetic Restorative Systems :
ā¢ Direct Composites
ā¢ Indirect Systems
ā¢ Composite Inlays & Onlays
ā¢ Ceramimc Inlays &Onlays
ā¢ Direct Systems
ā¢ Composite Inlays & Onlays
20. ā¢ Same as in cast restoration without bevel / flares.
ā¢ Occlusal reduction be 2mm and axial reduction
be 1.5mm
ā¢ All internal line angles are rounded to prevent
stress formation.
ā¢ Occlusal divergence of 10Ā°.
ā¢ Occlusal step depth 1.5 - 2mm
ā¢ Pulpal floor Flat & Smooth.
21. ā¢ The preparation is etched for 15 - 20
secs then dried.
ā¢ Bonding agent applied and cured for 30
secs.
ā¢ Then Silane Applied cderamic restorations
or air abraided composite restoration is
applied with dual cure resin luting cement
and placed in preparation. excess is
removed and cured.
ā¢ Self etchind dual cure resins are available
e.g. Rely X(3M ESPE).
22.
23. ā¢ Direct composite for small ā medium cavities.
ā¢ Restoration involving the cusp best done by indirect
composite.
ā¢ Single/limited teeth with wider restorations best done with
semi direct composite.
ā¢ If several teeth are to be restored best done with indirect
composites.
ā¢ If a amalgam restored teeth then go for direct composite.
24.
25.
26. ā¢ A water soluble separating medium & matrix
band is placed on tooth after preparation.
ā¢ Then it is filled by composite cements and light
cured.
ā¢ The restoration is teased out of the preparation
so all undercuts in preparation must be remove
for easy removal.
ā¢ The restoration is light cured extraorally
(Secondary polymerization)
ā¢ Then finished and polished extraorally.
ā¢ Finally Luted onto the tooth.
27. ā¢ Mainly for one or two surface cavity restorations.
ā¢ Sufficient taper of minimum 15Ā°.
ā¢ Walls smooth with interlocking.
ā¢ Proper separating medium to be used.
28.
29. ā¢ In direct/ indirect procedure the impression is made of the
prepared tooth and master cast is fabricated.
ā¢ Direct hybrid resin is used to build-up the restoration in
cast, and light cured and additional secondary
polymerization is done.
ā¢ Finishing and polishing is done last.
ā¢ Tooth Preparation:
ā¢ Same as direct resin onlay
ā¢ Shallow undercuts need not be worried of.
30.
31. ā¢ Available through commercial labs.
ā¢ Fabricated on the die.
ā¢ Either microfilled / Hybrid composites.
ā¢ New generation polymers like ceromers or ceramic
optimised polymers can be used.
ā¢ Ceromers ā ArtGlass( Heraeus Kulzer ), Targis( Ivoclar
Vivadent)
ā¢ Polymerized in specialized unit to achieve a high degree of
polymerization.
32. ā¢ Same as in cast restoration.
ā¢ Tapered carbied bur/diamond bur used.
ā¢ A rougher preparation aids in bonding of the final
restoration.
33. ā¢ Open contact and improper proximal contact avoided.
ā¢ Marginal leakage dose not occur as polymerization done
extra orally.
ā¢ Superior physical properties as done extra orally.
ā¢ Increased cost and time factor.
ā¢ Requires adequate laboratory skill for fabricating these.
34. ā¢ Esthetic requirement of the patient.
ā¢ Large cavities.
ā¢ Teeth with large restorations.
ā¢ Heavy or abnormal occlusal forces.
ā¢ Inability to obtain moisture free environment.
ā¢ Deep subgingival preparations.
35. ā¢ Initially formed on the die.
ā¢ Initially light cured for 1min with LED curing unit.
ā¢ Secondary polymerization by placing restoration in the
curing oven.( exposing the restoration to additional light
and heat for 7 mins.
ā¢ Removed and cooled.
ā¢ Finishing and polishing done.
36.
37. ā¢ Modern generation ceramic restoration where introduced
in 1983 by Horn JR.
ā¢ Ceramic materials employed for ceramic inlays and
onlays are all ceramic materials, these include:
ļ¼Aluminous porcelain e.g Hi-ceram.
ļ¼Glass ceramics e.g DICOR(Dentsply)
ļ¼Pressable glass ceramics, e.g IPS Empress, IPS Empress 2
(Ivoclar-Vivadent)
ļ¼Slip casting ceramics, e.g In-Ceram.
ļ¼CAD/CAM ceramics, e.g Procera, Cerec.
38. ā¢ Esthetic requirement of the patient.
ā¢ Large cavities.
ā¢ Teeth with large restorations.
ā¢ Heavy or abnormal occlusal forces.
ā¢ Inability to obtain moisture free environment.
ā¢ Deep subgingival preparations.
39. ā¢ Adhesion of resin luting cement to ceramics is far better
than to composite.
ā¢ It has long term occlusal stability.
ā¢ Better physical properties.
ā¢ Better shade matching capability.
ā¢ Repair of fractured ceramic restoration is difficult.
ā¢ Time consuming laboratory process and difinite two
appointment treatment procedure.
ā¢ Expensive restoration.
40. ā¢ Preparation walls should be 6-10Ā° occlusally divergent.
ā¢ Cuspal reduction of 1.5-2 mm in functional cusp and 1-
1.5 mm on non-functional cusp.
ā¢ All line angles and bevels are smoothly joined with no
interruption.
ā¢ Gingival, occlusal bevels and flares are prepared in a
manner such that a marginal cast gold metal of 40Ā° is
obtained.
ā¢ A carbide bur or diamond bur is used to create a rougher
preparation to aid in bonding of the final restoration.
41. ā¢ It involves impression taking either with rubber based
material or alginate.
ā¢ Ceramic restoration is fabricated using any one of
following techniques:
ļ¼ Firing
ļ¼Pressing
ļ¼Casting
ļ¼Machining.
ā¢ The finished and glazed ceramic inlay/onlay is etched
with hydrofluoric acid and luted onto preparation using
dual cure resin cements.
42.
43. ā¢ CEREC (Ceramic reconstruction system)
1980.
ā¢ CELAY System.
ā¢ Resin wax pattern fabricated and external
surface of pattern traced mechanically with a
probe and diamentions are given to the
computer to fabricate final ceramic
restoration.
44.
45. ā¢ Time saving procedure.
ā¢ High quality.
ā¢ High esthetics.
ā¢ High strength.
ā¢ Minimum voids in restoration.
ā¢ Marginal gap of about 52 micron(min 25 micron) is
present.
ā¢ Minimum staining can be applied externally.
ā¢ Costly procedure.
ā¢ Special gadget like optical scanner.
46. ā¢ Consist of,
ā¢ Intraoral camera,
ā¢ Video monitor,
ā¢ Computer,
ā¢ Milling chamber.
ā¢ Process,
ā¢ Scan tooth preparation.
ā¢ Feed data.
ā¢ Computer analyses the preparation.
ā¢ Restoration is desiged.
ā¢ Milling unit cuts the design from a ceramic block.
47.
48. ā¢ TOOTH PREPARATION:
ā¢ Similar to conventional indirect ceramic onlay
restoration.
ā¢ Occlusal aspect reduced to 2mm for clearance.
ā¢ All cavosurface margins are prepared to butt
joint(90Ė).
ā¢ Bevels and chamfers are avoided.
49.
50. ā¢ A dry field for proper scanning with precision.
ā¢ Tooth preparation is scanned using intra oral camera ā
optical impression.
ā¢ Tooth surface coated with reflective medium for better
scanning.
ā¢ Software designs the restoration, transferred to milling
unit.
ā¢ Milling unit has a diamond disk and cylindrical diamond to
cut the ceramic block.
ā¢ Removed from milling unit.
ā¢ Ceramic restoration is etched and silanated.
ā¢ Luted using dual cure resin cement.