INTRODUCTION ROLE OF CONTACTS AND CONTOUR HAZARDS TYPES

1. CONTACTS
AND
CONTOURS
DR. JAMES

2. CONTENTS
Introduction
Role Of Contacts And Contours
Benefits Of Ideal Contacts And Contours
Types Of Contacts And Contours
Problems Associated With Faulty Reproduction Of Contacts In
Restoration
Reproduction Of Contacts In Restoration
Classification Of Wedges
Wooden And Plastic
Wedging Techniques
Single Wedge Technique
Piggy Back Wedging
Double Wedge Technique
Wedge Wedging Technique
Automatrix
Hazards Of Improper Contacts And Contours
Recent Advances

3. Contact
• Contact is the term used to denote the
“proximal height of contour of
mesial and distal surface of the
tooth that touches its adjacent
tooth in the same arch.”
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

4. Contact
Point
• Contact point has been defined as the
point when teeth erupt and acquire
proximal contact with adjacent tooth
proximal attrition leads to the conversion
of contact point to contact area.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

5.  All teeth have there contact point centred faciolingual (slightly
buccal of the middle 3rd).
 2nd premolar / 1st molar / 2nd molar contact point have a straight
line that bisects every contact point

6.  Conserves the teeth from interproximal caries
 It creates a natural embrasure by maintaining good oral hygiene at
the interproximal area
 Preserves the stability and integrity of the arch by maintaining
normal mesio-distal relationship of teeth.
 Prevent food impaction interdentally
 Protect the soft tissue from periodontal disease

7. CONTACT POINTS
Mesially – contacts the incisal 3rd of crown
Distally – contact occurs slighty higher
Distal ouline of central insor are rounded
Incisal embrasures are slight
Central incisor

8. Lateral incisor
Lateral incisor has a shorter crown and more
rounded mesioincisal angle
Mesial contact area on lateral are above the
incisal 3rd of the tooth.
Embrasures approaching distally are larger than
mesial to central

9. Canine
Mesial contact area of canine are in junction
between incisal and middle 3rd
Distal slope of canine are larger
Distal contact area is at centre of middle 3rd of
crown.
Embrasures are larger than central and lateral
incisors

10. 1st premolars and 2nd premolars
Mesial contact area is cervical to the junction of
incisal and middle 3rd .
Embrasure b/w teeth have wide angle.
Form of these teeth creates wide occlusal embrasure

11. 2nd premolars and 1st molar
Contact area is cervical to the junction of incisal
and middle 3rd .

12. 1st 2nd and 3rd molars
Contact area appraoches the middle third of
the crown.

13. SIZE &LOCATION OF CONTACT POINT AND CONTACT
AREAS
Location of contact
Anterior teeth – Incisal 1/3rd
Posterior teeth – Junction of incisal and middle 1/3rd
Size of contact
Anteriorly, Posteriorly –contact area about 1.5-2mm

14. Contact Areas
• According to Zeisz and Nuckulls the contact area is
a flattened position of tooth,refers to the surface
area where the proximal surfaces of neighboring
teeth come in contact.
• Contact area is usually located in upper one third
of the crown of most of the tooth
• The proximal contact area is located in the incisal
third of the approximating surfaces of the maxillary
and mandibular central incisors,
• Faciolingually- positioned slightly facial to the
center of the proximal surface
• Proceeding posteriorly from the incisor region,
the contact area are located near the junction of
the incisal (or occlusal) and middle third.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

15. Role of
Contact
Area
•Allows a good support against masticatory
forces
•Promotes the deflection of the food through
the embrasure.
•Influences speech and cosmetics especially in
the anterior region.
•Improper restoration in the contact area will
cause
•displacement of the teeth
a)lifting forces of the teeth
b)rotation of the teeth
c)deflecting occlusal contact
d)food impaction.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

16. bucco-lingually or occlusal-gingivally causes improper shunting of
food because of narrow embrasure
this leads to food impingement in the contact area
PROBLEMS ASSOCIATED WITH FAULTY
REPRODUCTION OF CONTACTS IN
RESTORATION
Too Broad Contact
Ashwini, et al.: Clinical considerations in restorative dentistry Journal of the International Clinical
Dental Research Organization | July-December 2015 | Vol 7 | Issue 2

17. bucco-lingually or occluso-gingivally causes food impaction
vertically and horizontally due to wide embrasure in which lead to
greater food retention and plaque accumulation
TooNarrow Contact
Tooocclusally,bucallyorlingually
Contact area placed too occlusally, buccally or lingually will
result in flattened marginal ridge of the restoration
Ashwini, et al.: Clinical considerations in restorative dentistry Journal of the International
Clinical Dental Research Organization | July-December 2015 | Vol 7 | Issue 2

18. OPEN CONTACT
Causes accumulation of debris , plaque and damage to the periodontal disease
leading to food impaction
Contact point too gingivally will lead to increased depth of
occlusal embrasure leading to food impaction
Toogingivally

19. Interdental
Col
• Valley like depression situated apical to contact
point /contact area.
• Connects facial and lingual papillae
• Pyramidal or col shaped occupying the gingival
embrasure.
• Epithelium of col is thin and non keratinised.

20. Supragingival
margins
• Provides easy preparation of the tooth,
finishing of the margins, impression
making, fit and finish of the restoration.
• Verification of the marginal integrity of
the restoration is easiest.
• least irritating to the periodontal tissues
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

21. Subgingival
margins • If the margin is placed to far below the
alveolar crest it impinges on gingival
attachment and creates a violation of biologic
width.
• Subgingival margins increased plaque index,
gingival recession and increased pocket depth
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

22. Equigingival
margins
• Traditionally this type of margins were not
desirable-food accumulation which tends
to increased gingival inflammation and
minor gingival recession.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

23. Contours
• “Contour denotes some degree of
convexities and concavities on
the facial/buccal and
lingual/palatal surface of all teeth
that affords protection to the
supporting tissue during
mastication.”
• generally located at the cervical
third of the crown on the facial
and lingual surfaces of the incisors
and canines.
• The lingual surfaces of the
posterior teeth usually have their
height of contour in the middle
third of the crown.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

24. Role of
contact:
Allows “ normal healthy interdental
papilla to fill the interproximal
spaces.”
“Stabilizes and maintains the
integrity of dental arches.”
It prevents the food from getting
trapped in between the teeth
It prevents the impingement to the
gingival tissue.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

25. Role of
contour:
They are involved in occlusal static and
dynamic relation as they determine the
pathway for the teeth into and out of
centric occlusion.
They fullfill the function and form of
embrasures.
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

26. On the Facial side: height of contour of all teeth - Cervical 3rd.
On the Lingual side: height of Contour are:
a) Anterior Teeth: Cervical 3rd.
b) Posterior Teeth: Middle Third.

27. BENEFITS
OF AN
IDEAL
CONTACT
&
CONTOUR
1. Conserves the health of peridontium
2. Prevents food impaction
3. Makes area self cleansable
4. Improves longevity of proximal
restorations
5. Maintains mesiodistal relationship of
the teeth
Ashwini, et al.: Clinical considerations in restorative dentistry Journal
of the International Clinical Dental Research Organization | July-
December 2015 | Vol 7 | Issue 2

28. CONTACT TAPERING SQUARE OVOID
Betwee
n
incisor
s
Incisal ridge- incisally ,
Labially - labiolingually
Incisal ridge-
incisally , Labially -
labiolingually
Slightly lingual to
incisal ridge
Canine Mesial-
contacts
incisal ridge
Distal-contacts
middle third
Close to incisal ridge
incisally
Labiolingually
Close to incisal
ridge incisally
Bicuspids Almost at bucco-axial
angle
Towards bucco-
axial angle
Junction of
buccal &
middle third
Occlusal - junction of
occlusal & middle 3rd of
crown
Occlusal periphery -
occlusal third

29. Molars
(mesial
contact
)
Almost at bucco-
axial angle of
tooth
Occlusal - at junction
of occlusal & middle
third of crown
Molars
(distal contact)
Buccal periphery at
middle third
More lingually
deviated than
mesial
Buccal
periphery -
central
groove

30. OVERCONTOUR
 Inadequate stimulation by passage of
food
 Posing greater risks to periodontal health
.
 Both supragingival and subgingival
plaque accumulation occurs.
UNDERCONTOUR
 Results in overhanging of restoration and
trauma to soft tissue
ADEQUATE CONTOUR
 Stimulation of supporting tissues
 Healthy peridontium

31. Types of
Contact
Areas
• TAPERED TYPE
• SQUARE TYPE
• OVOID TYPE

32.  In an inciso-apical direction-
contact of maxillary central and
lateral incisors start incisally
near the incisal edges.
 In a labio-lingual direction -
labial to the incisal edges.
 Tapered cuspid - angular with
the mesial contact area close
to the incisal edges & distal
contact area near the center of
the distal surface.
 As these crowns taper lingually,
the contact areas occur
buccally at buccal axial angle of
the tooth.
 The bicuspid contact -just
gingival from the junction of
the occlusal and middle third
of the crown.
1. TAPERED
TYPE

33. The concavities are more pronounced
on mesial than on distal surfaces
Bucco-lingually -Mesial contact of molar
contacts the mesio-buccal axial angle of
the tooth
Proximal contour -starts at the CEJ ,
surface presents a concavity to the
contact areas and convexities to the
crest of the marginal ridges.
Labiolingually- gingival embrasures
between anterior teeth are extended
incisally and wider at gingival crest .
Buccolingually -gingival embrasures
between posterior teeth are broad
whereas the lingual embrasures are
wide

34. 2. SQUARED
TYPE
 This type of tooth is bulky and
angular, with little rounded contour.
 Teeth have relatively short cusps
 Labiolingually , incisally -The incisor
contacts are in a line with the incisal
edges,
 Occlusal contact of the posterior teeth -
occlusal one third of the crown.
Proximal contours of these type of
teeth tend to become a plane instead of
curved surface
 Buccolingual concavities are found on
mesial surface of maxillary 1 st and 2nd
molars and maxillary 1st premolars
 Distal surface are either flat /slight
convex from buccal to lingual surface

35.  Transitional type between the
tapered and square types. Its
surfaces are primarily
convex.
 In an inciso-gingival direction-
the mesial contact of the
incisors origins from 1/4th
the height of the crown
from the incisal edges.
 The distal contact -1/3rd to
½ the height of the crown
from the incisal edge
 Proximal contours of ovoid
anterior teeth are convex
from the incisal angle to the
CEJ.
 The mesial surfaces of
ovoid molars present
convex areas which are less
extensive than those on distal
surfaces
3. OVOID
TYPE

36. V-shaped spaces between the teeth that originate at the
proximal contact areas between adjacent teeth.
TYPES – occlusal , gingical and incisal embrasures
Serves 2 purposes –
 Provides a spillway for passage for food during mastication
 Prevents food from being forced into the contact area

37. This is an immediate type of separation.
This type of tooth movement involves separation
of teeth proximally at the point of insertion of
separator.
The amount of separation produced should not
exceed 0.2-0.5mm.
Rapid separation can be done by two method
a)Wedge method
b) Traction method

38. In this method space is created by inserting wedge
shaped device between the teeth.
There are two types of separator
1)Wooden / Plastic wedges
2)Elliot separator

39. 1)On the basis of method of
fabrication
a)Custom made wedges
b)Pre-fabricated wedges
2)On the basis of material
used for fabrication
a)Wooden wedges
b) Plastic or synthetic resin
wedges

40. PRE-FABRICATED
WEDGES
• They are in triangular in shape and supplied in
different size.
• Their shape should modified by trimming to
exactly meet that of the gingival embrasure.

41. • These are transparent plastic wedges ,which are available -built in
light reflecting property.
• Indication
Class II composite restoration : These light transmitting wedges
help to assist in directing light into inter proximal areas during initial
stages of class II composite curing .
LIGHT TRANSMITTING WEDGES

42. 1. Single wedge technique
• Single wedge is placed in the
gingival embrasure
2. Piggyback wedging
• A second wedge is placed on
top of the first wedge to wedge
adequately the matrix against
the margin
• Indicated for patients whose
interproximal tissue level has
receded.

43. 3. Double wedging technique
• Here, 2 wedges, one from the facial
embrasure and the other from the
lingual embrasure are used.
• Used when proximal box is wide facio-
lingually.
4. Wedge wedging technique
• Used in cases when there is a gingival
concavity
• A second wedge is inserted between
the first wedge and the band.

44. Functions of Wedges
• They create space between teeth to compensate the
thickness of matrix band.
• Immobilize the matrix band.
• Closely presses the matrix band against the tooth in the
gingival area of the preparation preventing any restorative
material escaping below the band.
• Maintaining the health of interdental gingiva by
preventing material from impinging into the tissues.
• Protect the gingiva from unexpected trauma.

45. BIOLOGIC
WIDTH
 Represents combination of epithileal and connective tissue ie.sulcus of
0.69 mm, epithelial attachment of 0.97 mm and a connective tissue width of
1.07 mm coronal to the crest of the alveolar bone
 It provides the natural seal that develops around the tooth protecting the
alveolar bone from the infection and the disease
 Restoration that impinges upon biologic width would lead to progressive
periodontal disease.
 The margins of restoration should be more than 2mm coronal to alveolar
crest.

46. • Biologic width may vary from tooth to tooth which increases
progressively from anterior to posterior teeth
Anterior teeth – 1.75 mm
Premolars - 2.97 mm
Molars - 2.08 mm

47. Elliot Separator
• It is also called crab claw
separator.
• It is mainly used for:
1)Examination of proximal
surface
2)Final polishing of already
restored proximal surface.

48. Matrix band
 Applied in procedures where temporary wall is created
opposite to axial wall that surrounds the area of the
tooth structure
 Forms a 360 degree contour and a wall replacing the
missing wall in cavity preparation.
 The height of the band should be such that it extend
2mm above the marginal ridge and 1mm below
gingival margin of the preparation.

49. CLASSIFICATION OF MATRIX
BAND
1. Based on mode of retention:
i. With retainer (Tofflemire matrix)
ii. Without retainer (Automatrix)
2. Based on type of band
i. Metallic non transparent
ii. Nonmetallic transparent
3. Based on type of cavity
Class I cavity - Double banded Tofflemire (barton’s
matrix)

50. Class II
cavity
a) Single banded
Tofflemire
b) Ivory matrix No. 1
c) Ivory matrix No. 8
d) Copper band
matrix
e) Automatrix
Class III
cavity
a. Mylar strip
b. S-shaped
Class IV
cavity
a. Mylar strip
b. Transparent
crown matrix
c. Modified S-
shaped
Class V a. Cervical matrix
b. Window matrix

51. Ideal requirements of Matrix
 It should be simple in design.
 It should be easily applied and readily removed
 It should be rigid enough to withstand
condensation pressure preventing the restorative
material bulging out.
 It should be able to adapt with the shape and
position of different types of tooth.
 It should be non reactive to the tissue and restorative
material.
 It should be inexpensive and readily available.
 It should be easy to sterilize.

52. Ivory Matrix No.1
 Band encircles the posterior proximal
surfaces
 indicated in unilateral class II cavities.
 Band is attached to the retainer via a
wedge shaped projection.
 Adjusting screw at the end of the
retainer adapts the band to the
proximal contour of the prepared tooth.

53. Ivory Matrix No. 8
• Consists of band that encircles the
entire crown of the tooth.
• Indicated for bilateral class II
cavities.
• Circumference of the band can be
adjusted by adjusting the screw
present in the retainer.

54. Roll in band matrix ( Automatrix)
• Retainerless matrix system with 4 types of
bands that are designed to fit all teeth
regardless of circumference and height.
• Available as 4 , 6 and 8 mm thickness bands.

55. HAZARDS OF IMPROPER CONTOURS:
Facial and lingual convexities:
Overcontoured curvatures can create a favorable
environment for the accumulation and growth of
cariogenic and plaque bacteria at marginal gingiva ;
apical to the height of contour.
This results in chronic inflammation of the gingiva.

56.  Facial and lingual concavities:
 Mislocated concavities - premature contacts during
mandibular movements
 Excessive concavities - extrusion, rotation or tilting of
occluding cuspal elements into non-physiologic relations with
opposing teeth.
 Deficient concavities at these locations - can create
restoration overhangs which increases the chance for plaque
retention.

57.  Proximal contours:
 Restoration that does not reproduce the concavities and
convexities will lead to restoration overhangs and under
hangs, vertical and horizontal impaction of debris and
impingement upon the adjacent periodontal structures.
 Too narrow embrasures predispose to heavier stresses. Too
wide embrasures offer little protection to the underlying soft
tissue

58. 99

59. CONTACT FORMING INSTRUMENTS
• These are special instruments designed to create optimum
contacts with posterior teeth.
Eg:
• Contact Pro
• Optra contact

60. CONTACT RINGS
• Work by providing slight separation of the contacting
teeth.
• Spring action applies equal and opposite forces
against the teeth thus providing optimum
separation.

61. Palodent Bitine Composi-Tight
First generation systems

62. Eg:-
Composi-Tight 3D soft face ring system
V3 ring system.
Second Generation Rings

63. PRECONTOURED SECTIONAL MATRIX
BANDS

64. Fender Wedges
 Combination of a steel plate and a
plastic wedge.
 Should be inserted with firm pressure
providing a tight stable fit throughout
preparation.

65. PRO MATRIX SYSTEM
 Available as a
standard matrix
band and a
contoured band“
 These matrix bands
are pre-assembled.
 They save time and
are very
convenient.”

66. Conclusion
• To provide optimum contacts and contours,
selection of the matrix should be considered
based on its ease of use and efficiency.
• Proper restoration of the anatomical landmarks
is important for enhancing the longevity of
restorations as well as to maintain the occlusal
health and harmony.

67. REFERENCES
• TEXTBOOK OF MARZOUK – CLINICAL OPERATIVE
DENTISTRY
• Ashwini, et al.: Clinical considerations in restorative
dentistry Journal of the International Clinical Dental
Research Organization | July-December 2015 | Vol 7 |
Issue 2
• TEXTBOOK OF STURDEVANT -THE ART AND SCIENCE OF
CLINICAL OPERATIVE DENTISTRY
• TEXTBOOK OF WHEELERS
• TEXTBOOK OF VIMAL SIKHRI -THE ART AND SCIENCE OF
CLINICAL OPERATIVE DENTISTRY