Contacts and contours

1,391 views 119 slides Jan 08, 2021
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About This Presentation

presentation includes the various methods for maintaining proper contacts and contours in our dentition


Slide Content

CONTACTS AND
CONTOURSCONTOURS
DR MEENAL ATHARKAR
MDS
DEPT OF CONSERVATIVE DENTISTRY AND ENDODONTICS

CONTENTS
•Introduction
•Definitions
•Benefits of ideal contact and contour
•Proximal contact area•Proximal contact area
•Types of teeth
•Proximal contacts of various teeth
•Methods of testing a contact area
•Problems associated with faulty reproduction of
contacts in a restoration

CONTENTS
•Embrasures
•Contact and embrasure relationship
•Marginal ridges
•Contours•Contours
•Traditional concepts of crown contour
•Types of contour and their management

CONTENTS
•Procedures for proper contacts and contours:
1)Intraoral procedures
2)Extraoralprocedures
•Recent advances•Recent advances
•Conclusion
•References

INTRODUCTION
•A healthy dentition comprises of fully erupted
teeth with proper occlusaland proximal contacts
that help to stabilize and maintain the integrity of
the arch.
•A clinician’s role is to re-establish the original or •A clinician’s role is to re-establish the original or
correct the faulty contact to form physiologically
stable contact and inabiltyto restore this
relationship disrupts harmony and can result in
deleterious consequences like food impaction,
caries, drifting, tilting and rotation of teeth.

INTRODUCTION
•A thorough knowledge of the contacts and
contours of various teeth is mandatory for
understanding-
1.Predisposing factors of proximal caries like faulty
inter-relationships.inter-relationships.
2.Significance of marginal ridges, embrasures for
re-establishing the form and function of
restored teeth.
3.Periodontal aspect and health of tooth to be
restored.

DEFINITIONS
•PROXIMAL CONTACT AREA:
•It denotes the area of proximal height of
contour of the mesialor distal surface of a
tooth that touches (contacts) its adjacent tooth
in the same arch
•CONTOURS:
•The facial and lingual surfaces possess some
degree of convexity that affords protection and
stimulation of the supporting tissues during
mastication.
(Sturdevant)

BENEFITS OF IDEAL CONTACT AND
CONTOUR
•Conserves the health of periodontium
•Prevents food impaction
•Makes area self cleansable
•Improves longevity of proximal restorations•Improves longevity of proximal restorations
•Maintains normal mesiodistalrelationship of
the teeth in the dental arch

PROXIMAL CONTACT AREA
•Contact point and contact area:
•When teeth erupt to make proximal contact with
previously erupted teeth, there is initially a contact
point.
•The contact point becomes an area because of wear of •The contact point becomes an area because of wear of
one proximal surface against another during
physiologic tooth movement.
•The physiologic significance of properly formed and
located proximal contacts cannot be overemphasized;
they promote normal healthy interdentalpapillae
filling of the interproximalspaces.

Dental anatomy:theform and
function of permanent teeth.

Importance of contact
•Preservesthestabilityandintegrityofthearchby
maintainingnormalmesiodistalrelationshipof
teeth.
•Preventfoodimpactioninterdentally
•Protectthesofttissuefromperiodontaldisease•Protectthesofttissuefromperiodontaldisease
•conservetheteethfromproximalcaries
•Prematurerestorativefailuredoesnotoccurif
stableproximalcontactispresent.

Size of contact
Anteriorly-contact point
Posteriorly–contact area about 1.5-2mm

Location Of Contact
•Anterior teeth –incisalone
third
•Posterior teeth-junction
of occlusaland middle one
thirdthird

•The proximal contact area is located in the
incisalthird of the approximating surfaces of
the maxillary and mandibularcentral incisors.
•It is positioned slightly facial to the centerof •It is positioned slightly facial to the centerof
the proximal surface faciolingually.

•Proceeding posteriorlyfrom the incisor region
through all the remaining teeth, the contact
area is located near the junction of the incisal
(or occlusal) and middle thirds or in the
middle third.
•Because of these contacts being positioned •Because of these contacts being positioned
progressively lower cervically, larger incisalor
occlusalembrasures result posteriorly.

TYPES OF TEETH

1)Tapering:
•Wide crowns
•Narrow cervical region
3)Ovoid:
•A transitional type between
tapering and square types•Narrow cervical region
2)Square:
•Bulky
•Angular
•With little rounded contours
•Surfaces are convex but
infrequently they may be
concave

Tapering square ovoid

Methods of testing a contact
•Visual inspection
•Digital test
•Radiographic –paralleling technique

Contact Relationships Between Posterior Teeth
A B C
A. Point or marble-like contact areas present at time of eruption.
B. Broad flat contact areas resulting from excessive wear.
C. Typical contact areas resulting from the usual amount of wear
observed in a patient of middle age.

In general,
The smallest posterior contacts occur on the mesial
surfaces of the maxillary and mandibularfirst
bicuspids.
surfaces of the maxillary and mandibularfirst
bicuspids.
Then it become progressively larger from the first
bicuspidsdistally through the molars.

Problems associated with faulty
reproduction of contacts in a
restoration
1)Improper contact size
a)Too broad contact :
• It will change the tooth anatomy
• It will change the interdental‘col’ by broadening • It will change the interdental‘col’ by broadening
it. The delicate non keratinized epithelium may
get damaged increasing the chance of
periodontal tissue.
• With too broad contact the interdentalarea is
difficult to clean increase the risk of future decay.

b)Too Narrow contact :
• It will change the tooth anatomy
• The embrasure size will increase leading to
impaction of food vertically and horizontally, impaction of food vertically and horizontally,
thereby damaging periodontal tissue.

2)Improper contact location
•If Contact are placed :
a)Too occlusally-It will cause flattening of
marginal ridges, resulting in too shallow
occlusalembrasure
b)Too buccally/lingually-will encroach upon the
respective embrasure
c)Too gingivally-will reduce the size of gingival c)Too gingivally-will reduce the size of gingival
embrasure and encroach upon interdental
gingiva

3)Open contact:
•Open contacts would create the problem,
ready inflow of food causing accumulation of
debris , plaque and damage to periodontiumdebris , plaque and damage to periodontium
leading to the periodontal disease

EMBRASURES
•Definition:
•Embrasures are V shaped spaces that originate at
the proximal contact areas between adjacent
teeth and are named for the direction towards
which they radiate. (Sturdevant)which they radiate. (Sturdevant)
•Cervical embrasure:
•When gingival recession occurs between the
teeth, the interdentalpapilla and bone no longer
fill the entire interproximalspace. These voids
exist cervicallyto the contact areas and are called
cervical embrasures.

Tapering square ovoid

CONTACT AND EMBRASURE RELATIONSHIPS

Anterior:-
Maxillary and Mandibular Teeth
The lingual embrasures widen out more than the labial embrasures
due to the tapering cingulum portions of the anterior teeth.

Posterior: Maxillary Teeth
•A buccal view shows the contact areas of these to be located in the
occlusal thirds of the crowns.
•The occlusal embrasures are not as wide or as deep as the
embrasures between the first bicuspids and the cuspidteeth .
•The gingival embrasures are considerably larger in depth and width
than the occlusal embrasures and are quite uniform between these than the occlusal embrasures and are quite uniform between these
teeth.

Posterior :Mandibular Teeth
•An occlusal view shows the contact areas to be centered near to the
midline of the crowns with only a slight tendency to be located
toward the buccal.
•The buccal and lingual embrasures between these teeth appear to
be progressively larger from the first molars to the third molars.
•It must be emphasized that the design of the contact areas and
embrasures between the teeth are influenced by the size and form
of the individual tooth crownsof the individual tooth crowns

Embrasures in anterior and posterior
teeth

Significance of embrasures
•The correct relationships of embrasures, cusps to sulci,
marginal ridges, and grooves of adjacent and opposing
teeth provide for the escape of food from the occlusal
surfaces during mastication.
•When an embrasure is decreased in size or absent,
additional stress is created in the teeth and the additional stress is created in the teeth and the
supporting structures during mastication.
•Embrasures that are too large provide little protection
to the supporting structures as food is forced into the
interproximalspace by an opposing cusp.
•A prime example is the failure to restore the distal cusp
of a mandibularfirst molar when placing a restoration.

•The lingual embrasures are usually larger than the
facial embrasures to allow more food to be displaced
lingually, because the tongue can return the food to
the occlusalsurface easier than if the food is displaced
facially into the buccalvestibule.facially into the buccalvestibule.
•The marginal ridges of adjacent posterior teeth should
be at the same height to have proper contact and
embrasure forms.
•When this relationship is absent, there is an increase in
the problems associated with weak contacts and faulty
embrasure form.

EMBRASURES
•Serves two purposes:
•Provides a spillway for passage of food during
mastication.
•Prevents food from being forced into the •Prevents food from being forced into the
contact area.

MARGINAL RIDGES
•Rounded borders of enamel that forms mesial
and distal margins of occlusalsurfaces of
molars and premolars and mesialand distal
margins of lingual surfaces of incisors and margins of lingual surfaces of incisors and
canines.

A marginal ridge of proper dimensions help in :
Occlusalcuspalanatomy
creating a adjacent Triangular fossa.
Producing adjacent OcclusalembrasureProducing adjacent Occlusalembrasure

Importance of marginal ridge:
In restorative dentistry
•A marginal ridge should always be recorded in two planes bucco-
lingual and occluso-cervical.
•It should be compatible in height with the adjacent tooth.
•Should be compatible with the occlusal cusp anatomy, creating a
pronounced adjacent triangular fossaand producing an occlusal pronounced adjacent triangular fossaand producing an occlusal
embrasure.

Marginal ridge with normal occlusion
Clinical considerations in restorative dentistry —A narrative review

Faults in marginal ridge formation during restoration:
No marginal ridge
•This resulting in drifting of the adjacent tooth with normal marginal
ridge
•Slight tilting of the tooth with no marginal ridge
•Food impaction vertically between the teeth
Clinical considerations in restorative dentistry —A narrative review

Clinical considerations in restorative dentistry
—A narrative review

Clinical considerations in restorative dentistry
—A narrative review

Clinical considerations in restorative dentistry
—A narrative review

Clinical considerations in restorative dentistry
—A narrative review

Clinical considerations in restorative dentistry
—A narrative review

CONTOUR
•The facial and lingual surfaces possess some
degree of convexity that affords protection
and stimulation of the supporting tissues
during mastication. (Sturdevant)during mastication. (Sturdevant)
•This convexity generally is located at the
cervical third of the crown on the facial
surfaces of all teeth and the lingual surfaces of
the incisors and canines.

•Functions of contour:
•Acts in deflecting food only to the extent that
passing food stimulates by gentle massaging
rather than irritates the investing tissues.rather than irritates the investing tissues.
•Maintenance of periodontal tissues.
•Proximal height of contour helps to provide
contacts with proximal surfaces of the
adjacent teeth which prevents food
impaction.

•Provide adequate embrasure space gingivally
of the contacts for gingival tissues, supporting
tissues, blood vessels and nerves that serve
the supporting structures.the supporting structures.
•For upper anterior teeth-essential
determinant for mandibularmovement.
•Serves to decrease the tooth bulk from its
gingival third to incisalthird.

TRADITIONAL CONCEPTS OF CROWN
CONTOUR
•Food deflecting theory
•Muscle action theory
•Plaque retention theory
•Anatomical theory•Anatomical theory
•Margin placement theory
Current controversies in axial contour design

•Food deflecting theory:
•A) According to Wheeler:
•He proposed that convexities should be created in the
cervical third of artificial crowns.
•These convexities were to deflect food away from free
gingiva.
•This "shunting" idea was based upon the premise that
•(1) food forcefully contacts free gingivain mastication •(1) food forcefully contacts free gingivain mastication
and
•(2) this contact acts as an etiologic agent in gingival
disease.
•Wheeler went on to state that these contours, usually
called cervical ridges or cervical contours, have
considerable physiologic importance.

•Wheeler believed that properly designed
curvatures allow sufficient functional
stimulation for necessary tissue massage.
•He further stated that whether or not these
theories are true, these curvatures must be theories are true, these curvatures must be
physiologic because they are so consistent and
uniform.

•B) According to Morris:
•He noted that the position of the gingival margin is, in part,
determined by the buccalor lingual tooth surface
prominences, "being more apical with greater prominence
and more coronal with lesser prominence.“
•His emphasis on the importance of accessibility to oral •His emphasis on the importance of accessibility to oral
hygiene measures and self cleansing by muscle action and
saliva is significant.
•The importance of embrasure spaces was also emphasized
because encroachment of these spaces would decrease
accessibility.
•His concept was inspired by Hirschfeld'sclassic
observations of clinical and skull materials

•C) According to Hirschfeld:
•He noticed that a linguallymalposedtooth
possessed a thicker and more coronal alveolar
buccalplate than the properly positioned
adjacent teeth.
Conversely, the lingual plate was thinner and •Conversely, the lingual plate was thinner and
more apically positioned than the adjacent teeth.
•Besides, the buccal(or lingual) alveolar crest was
flat if the contiguous tooth surface was flat, or it
curved coronallytoward the proximal areas if the
tooth surface was convex mesiodistally.

•D)According to Herlandset al:
•They found that contours based on the food-
deflecting concept resulted in crowns that
were overcontoured, thus causing, rather than were overcontoured, thus causing, rather than
preventing, gingival inflammation.
•Their efforts to prevent food impaction
produced contour thicknesses never seen in
nature.

•Herlandsfound that:
•1. The impaction mechanism requires certain physical
conditions.
•The substance being impacted must be fairly firm in
consistency or else it will be mashed, and there must consistency or else it will be mashed, and there must
be a propelling force directing it toward an easily
accessible cul-de-sac.
•Both forces and substance must exist within confining
resistant walls.
•More vigorous mastication and harder foods result in
heavily keratinized and clinically healthy gingivae

•2. The maximum bulge in natural crown contours is no
more than 0.5 mm, and this is considered as inadequate
protection against an impaction mechanism.
•3. Complete lack of contour is often observed when a tooth
prepared for full coverage is left uncovered for an extended
period of time, but the surrounding gingivaeare usually
healthy.
•4. The gingival sulcusitself is not an easily accessible cul-
de-sac. The free gingivais held firmly against the crown by de-sac. The free gingivais held firmly against the crown by
the supra-alveolar system of connective tissue fibers.
•5. An outward current of serum will flush foreign matter
from the gingival sulcus, the flow of which is increased by
heavier muscular action and harder food.
•6. Embrasure contours are possibly even more important
than buccalor lingual contours.

•Muscle action theory:
•A) Herlandset al and Morris introduced the
"muscular-action concept" which used the
rationale of muscular moldingand cleansing,
rather than food impaction, to explain the rather than food impaction, to explain the
observable clinical phenomena found around the
natural and artificial crowns.
•They considered this concept to be a more
accurate guide for the construction of gingivally
tolerated full crowns

•B) According to Perel:
•He studied the relationship between axial tooth
contour and marginal periodontiumon dogs.
•Procedures producing undercontoursand overcontours
on buccaland lingual crown surfaces were performed.
•Clinical and microscopic evaluations were made in
respect to the condition of the marginal periodontium
and the crevicularareas.
respect to the condition of the marginal periodontium
and the crevicularareas.
•He concluded that:
•1. Undercontouringof axial surfaces did not produce
any significant changes in healthy gingivae.
•2. Overcontouringof axial surfaces, on the other hand,
produced inflammatory and hyperplasticchanges in
the marginal gingivae.

•Plaque retention theory:
•The proponents of this concept prefer axial
contours of artificial crowns which facilitate
oral hygiene measurements and promote self-
cleaning by muscle action of the tongue, cleaning by muscle action of the tongue,
cheeks, and lips.
•Furthermore, they stated that crown contour
should not harbour any plaque traps

•Anatomic theory:
•Kraus, Burch and MiIIerintroduced the anatomic or
biologic concept of tooth contour, a contour which
simulated natural, healthy teeth.
•They considered that a biologic contour was a self-
protective contour to the supporting tissues and
defended the gingival unit, attachment apparatus, and defended the gingival unit, attachment apparatus, and
protected bone from trauma and irritation.
•Improper contour often induced early breakdown of
the supporting structures and tooth tissue, resulting in
premature loss of teeth.

•They stated that facial and lingual convexities form the
height of contour of tooth crowns, which are located at
the gingival third of each tooth and are approximately
one-half millimeterwider than the adjoining
cementoenameljunction (CEJ). cementoenameljunction (CEJ).
•The exception to this general rule is on the lingual
surface of the lower molars and second premolars.
•There, the convexities measure approximately one
millimeterand are located halfway between the
occlusalplane and the gingival margin.

•Margin placement theory:
•Plays a significant role in gingival health.
•The majority of data indicate that subgingival
margins can be conducive to plaque
accumulation and to periodontal disease.
•A)According to Wagman:•A)According to Wagman:
•He began to observe the function of subgingival
contours pertinent to gingival health. He
emphasized the importance of establishing the
proper contour to maintain the "knife-like" shape
of the free gingival margin. This was to facilitate
the removal of microbial plaque.

•He believed that subgingivalcontour should be
made convex facially and lingually.
•This was to protect the gingival sulcusand to
promote a knife-like, free gingival margin. promote a knife-like, free gingival margin.
•The degree of these convexities should not
exceed one-half of the thickness of the gingivaat
the height of its attachment.
•Proper interproximalcontour was also suggested,
and undercontourwas preferred to overcontour.

•B)According to Weisgold:
•He stated that subgingivalcontour should be dictated
by the level of the free gingival margin.
•When the gingival margin is placed coronal to the CEJ,
the subgingivalcontour should be made convex. the subgingivalcontour should be made convex.
•On the other hand, when gingival margin is located
below the CEJ (on the root surface) due to recession,
the subgingivalcontour should be made flat.
•His clinical experiences have shown that the artificial
crown portion placed subgingivallyshould generally
imitate the original shape of the tooth.

Types of contour

•Improper location and degree of facial or
lingual convexities can result in serious
complications, where the proper facial
contour is disregarded in the placement of a
cervical restoration on a mandibularmolar. cervical restoration on a mandibularmolar.
•Overcontouringis the worst offender, usually
resulting in flabby, red-colored, chronically
inflamed gingivaand increased plaque
retention.

FACIAL AND LINGUAL CONTOURS
•Facial and lingual convexities•Facial and lingual convexities
•Facial and lingual concavities

Facial and lingual convexities
•It has been revealed that there is always more inherent danger in
overconvexrather than under convex facial and lingual contour.
•The overconvexcan create an undisturbed environment for the
accumulation and growth of cariogenicplaque at gingival marginaccumulation and growth of cariogenicplaque at gingival margin

Facial and lingual concavities
•Deficient or mislocatedconcavities will lead to premature contacts
during mandibular movement
•Excessive concavities can invite extrusion,rotation,ortilting of •Excessive concavities can invite extrusion,rotation,ortilting of
occluding cuspalelements into non-physiologic relations with
opposing teeth.

Guidelines To Contouring Crowns:
Buccal and lingual contours-flat, not fat.plaque retention-infrabulge
of the tooth.Reduction or elimination of the infrabulgewould
reduceplaque retention
Open embrasures-If plaque is a primary etiologic factor in
gingivitis,thenevery effort should be made to allow easy access to gingivitis,thenevery effort should be made to allow easy access to
the interproximalarea for plaque control.Openembrasure spaces
will allow for this easy access .
Location of contact areas -Contacts should be high (directed
incisally) and buccal in relation to the central fossa(except
between maxillary first and second molars)

Proximal contour according to
different types of teeth
•Tapering teeth:
• Starting at CEJ, surface presents
concavity to contact areas , and
convex from there to crest of
marginal ridges. marginal ridges.
• Concavities are pronounced on
mesialsurface.

•Square teeth:
•Mesialsurfaces are Plane instead of curved.
• Distal surfaces are flat or slightly convex.

•Ovoid teeth:
•Convex from incisalangle to cervix.
• Premolar : bell shaped.
• Molars : mesialsurface is convex.

Management of faulty contours of
restorations
•1. Overcontouredproximal contour:
•Recontourif possible.
•Files-rheintrimmer
•WEDELSTAEDT chisel or bard parker no. 12 •WEDELSTAEDT chisel or bard parker no. 12
blade.
•Rotary instruments-sand disk, flame shaped
finishing burs

•2. Subgingivalcontours:
•Low speed reciprocating action hand piece
system
•EVA system using wedge shaped files.

•3. Undercontouredproximal contour:
•Replace the restoration

PROCEDURES FOR PROPER CONTACTS
AND CONTOURS
•Intraoral procedures:
1.Tooth movement
2.Matricing
•Extraoralprocedures:•Extraoralprocedures:
1.Wax pattern
2.Cast adjustments

•1) Tooth movement:
•Tooth movement or separation of teeth is
defined as the process of separating the
involved teeth slightly away from each other
or bringing them closer to each other, and/ or
changing their spatial position in one or more changing their spatial position in one or more
dimensions.

•Objectives:
•To bring drifted, tilted or rotated teeth to their
indicated physiological positions.
•To close space between teeth.•To close space between teeth.
•To move teeth to another location.
•To move the teeth occlusallyor apically to
make them restorable.

•To move teeth to a position so that when
restored, they will be in a most esthetically
pleasing situation.pleasing situation.
•To move teeth in a direction and to a location
to increase dimensions of available structure
for resistance and retention form.
•To create sufficient space for thickness of
matrix band.

•Methods of tooth separation:
•1. rapid or immediate separation
•2. slow or delayed separation

•1. rapid or immediate separation:
•Tooth movement is achieved rapidly over a
short period of time.
•May be achieved by wedge principle or •May be achieved by wedge principle or
traction principle.
•Mechanical type

•Indications:
•As preparatory to slow movement
•To maintain space gained by slow movement.
•Separation shouldn’t exceed 0.2-0.5 mm.•Separation shouldn’t exceed 0.2-0.5 mm.

•1. separation by wedge principle:
•In this principle, a pointed, wedge shaped
device is inserted between the contacting
teeth to produce the desired amount of teeth to produce the desired amount of
separation.
•eg. Elliot’s separator, wedges

•A) Elliot’s separator:
•Mechanical device.
•It has a single bow with two jaws which can be
adjusted by a knob.
•The jaws are positioned in the interdentalarea •The jaws are positioned in the interdentalarea
between the two contacting teeth gingival to the
contact area, without causing damage to the
interdentalpapilla.
•When the knob is turned clockwise, the jaws
move towards one another thereby wedging the
teeth apart.

•2. separation by traction principle:
•This employs a mechanical device to engage
the proximal surfaces of the contacting teeth
and bodily moves them apart to bring about and bodily moves them apart to bring about
the separation.
•Eg. Ferrier double bow separator.
•non interfering true separator.

•A) Ferrier double bow separator:
•Mechanical device has 2 bows.

•The advantage of this device is that the
separation is shared by both the contacting
teeth and is stabilized throughout the
operation.operation.
•This device is employed during cavity
preparation and finishing of class III direct gold
restoration.

Ferriordouble bow separator

B) Non interfering true separator

•2. slow or delayed separation:
•Indications:
•When teeth have tilted, drifted or rotated to a
considerable extent and rapid separation is considerable extent and rapid separation is
not useful.

•Slow separation is achieved by:
•1. rubber dam sheet
•2. separating rubber band
•3.Separating ligature wires•3.Separating ligature wires
•4.oversized resin temporary crowns
•5.orthodontic appliances

•1. rubber dam sheets:
•Separation occurs due to the thickness of the
sheet.
•The time taken-1to 24 hours or more
•In case pain develops dental floss may be used
to remove the rubber dam material.

•2. separating rubber band:
•A separating rubber band used for
orthodontic purposes can be used for
achieving slow separation.achieving slow separation.
•It can be stretched and positioned
interproximallybetween the teeth to produce
slow separation.

•separating rubber rings or bands:

•3. separating ligature wires:
•Orthodontic brass ligature wire can be passed
through the embrasure triangle beneath the
contact area to form a loop around the contact area to form a loop around the
contact area.
•The two ends can be twisted together to
create separation not beyond 0.5 mm.
•The wire can be tightened periodically to
increase the separation.

•4. Oversized resin temporary crowns:
•Temporary crowns are made oversized in the
mesiodistaldimensions and periodically resin
is added to the contact areas to increase the is added to the contact areas to increase the
amount of separation.

•5. orthodontic appliances:
•Fixed orthodontic appliances are the most
effective and predictable means of achieving
slow tooth movement.slow tooth movement.
•They may be used when extensive
repositioning of teeth is needed.

•Extraoralprocedures:
•1. wax patterns
•2. Cast adjustments

Recent advances
•1. contact forming instruments:
•create good contacts with posterior
composites.
•They push matrix towards contact area during
light curing.light curing.
•Egcontact pro, optracontact

2. XTS Freedman Contact Forming Composite
Instrument:
•provide improved contact forming for large
Class II Restorations.

•3. contact rings:
•Work by providing slight separation of
contacting teeth.
•2 generations:•2 generations:
•1
st
-(1990s)-palodentbitine
-contact matrix
-compositight

•2
nd
-compositight 3D soft face ring system
-V3 ring system

4.Kesling and dumbellseparators

CONCLUSION
•From cariogenicaspect, there may be only 20
occlusalsurfaces.
•There are 60 contacting proximal and 64 facial
and lingual surfaces.and lingual surfaces.
•Proper restoration of anatomical landmarks is
important for enhancing the longevity of
restorations as well as to maintain the occlusal
health and harmony

CONCLUSION
•Improper contacts can result in food impaction
between the teeth, producing periodontal
disease, carious lesions, and possible movement
of the teeth.
•In addition, retention of food is objectionable by •In addition, retention of food is objectionable by
its physical presence and by the halitosis that
results from food decomposition.
•Proximal contacts and interdigitationof the teeth
through occlusalcontacts stabilizes and maintains
the integrity of the dental arches.

REFERENCES
•Textbook of operative dentistry-VIMAL SIKRI.
1
st
edition.
•Dental Anatomy, Physiology, Occlusion-
WHEELER’s 5
th
edition.WHEELER’s 5
th
edition.
•Operative dentistry-Modern theory and
practice-M. A. MARZOUK 1
st
edition.
•Art and Science of Operative dentistry-
STURDEVANT 4
th
edition.

•Traditional concepts of crown contour-
•1)Current controversies in axial contour design.
(Anthony H. L. Tjan, Dr. Dent., Harvey Freed, and Gary
O. Miller)
•2)Desiginingcrown contour in fixed prosthodontics: A •2)Desiginingcrown contour in fixed prosthodontics: A
neglected arena.(YashpalSingh 1 Reader, Dept. of
Prosthodontics2 Monika Saini)
•Marginal ridge-
•Clinical considerations in restorative dentistry —A
narrative review (AshwiniTumkurShivakumar, Sowmya
HalasabaluKalgeri, SangeetaDhir)