This document discusses various types of mandibular major connectors used in removable partial dentures. It defines a major connector as the part that joins components on one side of the dental arch to the other. Six main types are described: lingual bar, sublingual bar, cingulum bar, lingual bar with cingulum bar, linguoplate, and labial bar. Each type has specific indications, contraindications, structural details, advantages and disadvantages. Proper design of mandibular major connectors considers factors like supporting tissues, tooth angulation, interarch space, and patient comfort.

1. MANDIBULAR MAJOR CONNECTORS
GUIDED BY:
DR. U.M. RADKE DR. N.A. PANDE DR. S DESHMUKH
HOD & GUIDE PROFESSOR READER
DR. T.K. MOWADE DR. R. BANERJEE DR. A. CHANDAK
READER READER READER
Presented by:-
Dr. Richa Sahai
II MDS

2. Contents
 Introduction
 Definition
 Ideal Requirements of mandibular major connectors
 Recording Lingual Sulcus
 Types of Mandibular Major Connectors
 Structural requirement for mandibular major connectors
 Types and designing of mandibular major connector
 Non-rigid mandibular major connectors
 Prosthodontic Considerations
 Recent advances
 Conclusion
 References

3. INTRODUCTION
“No Component of. Removable Partial Denture should be added arbitrarily or
conventionally. Each component should be added for a good reason and to
serve a definite purpose”.
WL McCraken

4. DEFINITION
 The part of a removable partial denture that joins the components
on one side of the arch to those on the opposite side. (GPT 9)

5. Basic Requirements of Mandibular Major
Connectors
 Rigid & Provides Cross-arch Stability- broad distribution of stress.
 Should not interfere with the tongue.
 Should not alter the contour of the lingual surface of the mandibular alveolar
ridge.
 Should not impinge on the oral tissues when the prosthesis is inserted.
 Cover no more tissue than is absolutely necessary.
 Does not contribute to the retention or entrapment of food particles.
 Has support from other elements of the framework to minimize rotational
tendencies during friction.
 Made from an alloy compatible with the oral tissues

6. DESIGN SPECIFICATIONS
Placement of borders: The superior borders are placed at least 3mm
from the gingival margins.
Relief is frequently required for mandibular arch:
1. To Prevent tissue impingement at rest & during function.

7. Relief required for tooth/tissue-borne prostheses depends upon:
a) Relationship of fulcrum line to major connector:
1) When the fulcrum line is posterior to the major connector, less
relief is required (28 guage,0.013 inches to 26 guage, 0.016 inches)

8. 2) When the fulcrum line is anterior to the major connector
 more relief is required (26 guage,0.016 inches to 24 guage,0.020
inches)

9. 3) Shape of adjacent alveolar ridge:
The lingual slope of the alveolar ridge influences the amount of relief
required, due to the rotation of the prosthesis tissue-wards.

10. Quality of supporting structures:
1) Periodontal status of abutment teeth
2) Quality of the supporting soft tissues
3) Bone index
4) Movement of the dento-alveolar segment
5) Lingual tori

11. RECORDING THE HEIGHT OF FLOOR OF THE
MOUTH
 Using a Periodontal probe

12. RECORDING THE HEIGHT OF FLOOR OF THE
MOUTH
 Make a custom tray 3mm short of elevated floor of the mouth.
 Then using an impression material record the area by asking the
patient to lick the upper lip.

13. Minimal support from the residual ridges so “indirect retention” is
needed to achieve stability.
Less surface area for the major connector.
More movable tissues in the mandibular arch.
The shape of the basal bone in the antero-lingual region i.e. lingual
sulcus area.
Level of the lingual frenum and its mobility.
Beading is contraindicated.
Esthetics to be considered in case of large interproximal spaces.
Anatomical and structural factors to be considered while
designing mandibular major connectors

14. Types of
Mandibular
Major
Connectors
Lingual bar
major connector.
Sublingual bar
major connector.
Cingulum bar
(continuous bar)
major connector.
Lingual bar with
cingulum bar
major connector Linguo-plate
major connector.
Labial bar major
connector.
Hinged
continuous labial
bar.

15. 1. LINGUAL BAR MAJOR CONNECTOR
Characteristics and location
 Half-pear shaped with bulkiest portion inferiorly located.
 Superior border tapered to soft tissue.

16. Indications:
8mm vertical space
between gingival margin
and floor of the mouth.
Contraindications:
Inoperable lingual tori.
High lingual frenum
attachment.
Interferences during
functional movements of
the floor of the mouth .

17. Advantages:
Simple design
Lingual bar connector
has minimal tissue
coverage
It does not contact the
teeth, so decalcification
of the tooth surface is
minimized.
Disadvantages:
It may be flexible if
poorly constructed.
Rigidity is less compared
to a well constructed
lingual plate.

18. BLOCK OUT & RELIEF OF MASTER CAST
 All tissue undercuts parallel to path of placement.
 An additional thickness of 32-gauge wax when the lingual surface of
the alveolar ridge is either undercut or parallel to the path of placement.
 No relief is necessary when the lingual surface slopes inferiorly and
posteriorly.

19. WAXING SPECIFICATIONS
 6 gauge, half-pear shaped wax form reinforced by 22-
 24 gauge sheet wax adapted to the design width.
 Long bar require more bulk than short bar.
Finish lines
 Butt joints with minor connectors for retention of denture bases.

20. 2. Sublingual bar major connector.

21. Indications:
It is recommended to be used in
shallow vestibules (4-6 mm of
vestibular depth).
When free gingival margins of anterior
teeth needs to be exposed
Contraindications:
Lingually tilted remaining natural
teeth.
Inoperable lingual tori.
High attached lingual frenum.
Presence of anterior lingual undercut.

22. Characteristics and Location:
 It is same as lingual bar except that the bulkiest portion is located to
lingual and the tapered portion is towards the labial.
 Inferior border is located at the height of the alveolar lingual surface.

23. 3. CINGULUM BAR MAJOR CONNECTOR

24. Indication
Improper axial
alignment of the
anterior teeth
In presence of
lingual torus
High frenal
attachment.
Contraindications:
In lingually tilted
anterior teeth.
Wide diastema
between mandibular
anterior teeth

25. Characteristics and Location
 Thin narrow metal strap located on cingula of anterior teeth, scalloped
to follow interproximal embrasures.
 Originates bilaterally from rests of the adjacent principle abutments.
BLOCKOUT & RELIEF
• No relief for cingulum bar except interproximal spaces.
WAXING SPECIFICATIONS
• A cingulum bar pattern formed by adapting two strips of 28- gauge,
3mm wide over the cingula and into interproximal embrassures.
FINISH LINE:
• Butt joint

26. 4. LINGUAL BAR WITH CINGULUM BAR MAJOR CONNECTOR
 It distribute stresses to all of the teeth with which it comes in contact
there by reducing the stresses to the underlying tissues.
 It is referred as “continuous lingual clasp” major connector, because
of series of clasp arms connected on the lingual surfaces of lower
anterior teeth.

27. Structural details:
 The two bars are attached by means of a minor connector with
positive vertical stops on either side to prevent settling and
orthodontic movements.
 If wide interproximal spaces are present then step backs can
provided for upper Cingulum bar to prevent its visibility.
Waxing specification:
1. Lingual bar component shaped same as lingual bar
2. Continuous bar pattern formed by adapting two strips of 28
gauge sheet wax , one at a time , over the cingula and into
interproximal embrasure .

28. Advantages:
Effectively extends indirect retention
in an anterior direction and is
supported by adequate rest.
It also contributes to horizontal
stabilization.
It helps in minor amount of support
to the prosthesis.
Free flow of saliva is permitted and
the marginal gingiva receives
stimulation.
Disadvantages:
Discomfort to the patient because it
alters the normal position of the
tongue.
Food entrapment.

29. 5. LINGUOPLATE MANDIBULAR MAJOR CONNECTOR
 If the rectangular space bounded by the lingual bar, the anterior tooth
contacts and cingula, and the bordering minor connectors is filled in, a
lingual plate results.

30. Characteristics and location:
 Half-pear shaped with bulkiest portion inferiorly located.
 Thin metal apron extending superiorly to contact cingula of anterior teeth
height of contour of posterior teeth.
 Scalloped contour of apron as dictated by interproximal block out.
 The superior border finished to continuous plane with contacted teeth.
Waxing specification
1. Inferior border — 6 gauge, half pear shaped wax form reinforced with 24
gauge sheet wax or similar plastic pattern
2. Lingual shield — 24 gauge sheet wax.

31. Indications:
High lingual frenum
attachments,
shallow vestibule.
Severe vertical
resorption
Presence of lingual
tori.
Stabilization of
periodontally
weakened teeth.
Contraindications:
In lingually inclined
mandibular anterior
teeth.
Wide embrassures
and diastema

32. Advantages:
Exceptional rigidity and provides more
support and stabilization when
compared to other connectors.
When it is supported at each end by a
rest it contributes to the action of
indirect retention.
When properly contoured and
fabricated, it will not cause interference
with tongue movements and will be
more comfortable to the patient.
Disadvantages:
Prevents physiologic stimulation of soft
tissues and thus may leads to
inflammation
Decalcification of teeth and
inflammation of marginal gingival and
metal display in wide interproximal
spaces.

33. Interrupted lingual plate:
 It is a type of the lingual plate recommended in wide interproximal areas.
Here the upper border of the lingual plate is cut longitudinally to prevent its
display through the wider interproximal spaces

34. 6. Labial bar major connector

35. Indications:
1. Lingually tilted
anterior and posterior
teeth (non correctable).
2. Large inoperable
lingual tori
3. Severe and abrupt
tissue undercuts.
Contraindication
Shallow labial vestibule.

36. Advantage:
When the remaining teeth are so far tipped
lingually that no other conventional major
connector can be used then labial bar is
considered
Disadvantages :
Pt acceptance is generally poor.
The bulk of the major connector distorts the
lower lip unless the lower lip is relatively
immobile
usually the labial vestibule is not deep
enough

37. Characteristics and Location:
 Half-pear shaped with bulkiest portion inferiorly located on the labial or
buccal aspect.
 Superior border tapered to soft tissue and 4mm inferior to labial gingival
margins.
 Inferior border located in the labial buccal vestibule; at the junction of
attached & mobile mucosa.

38. BLOCKOUT & RELIEF
•All tissue undercuts parallel to path of placement and when the labial surface
either undercut or parallel to the path of placement.
•No relief if labial surface of alveolar ridge slopes inferiorly.
WAXING SPECIFICATIONS
•6-gauge half-pear shaped wax form reinforced with 22-24 gauge
•Long bar more bulkier than shorter bar.
•Minor connector joined with occlusal or other superior components by a
approach.
FINISH LINE:
Butt joint

39. 7.HINGED CONTINUOUS LABIAL BAR.
•It is a type of the major connector which consists of lingual bar/plate and labial
bar.
• The lingual bar provides the rigidity to the framework and the labial bar
provides the extra retention and stability.

40.  Support provided by multiple rests on the remaining natural teeth.
 Stabilization and reciprocation provided by a lingual plate.
 Retention is provided by bar type retentive clasp arms projecting from the
labial or buccal bar and contacting the infra-bulge areas on the labial
surfaces.

41. Indications:
Missing key
abutments.
Unfavorable tooth
contour.
Unfavorable soft
tissue contours.
Teeth with
questionable
prognosis.
Contraindications:
Poor oral hygiene.
Shallow buccal /
labial vestibule.
High frenal
attachment
Poor patient co-
operation.

42. Advantages:
This design utilizes all
remaining teeth and
provides adequate
retention and stability.
Disadvantages:
Poor esthetics because
metal visibility.
Chances of unwanted,
orthodontic forces to the
teeth.

44. DESIGN OF MANDIBULAR MAJOR CONNECTORS
The basic principles of major connector design includes:
STEP 1
STEP 2
STEP 3
STEP 4

45. NON -RIGID MAJOR CONNECTORS

46. 1.Split Bar major Connector
 Split is provided between the denture base area and the major connector
(lingual bar).
 When occlusal forces are applied they are transferred more towards the tissue
supported base and then they are transmitted to the abutment teeth. Thus the
amount of tipping forces are reduced on the abutment teeth.

47. 2.Ticonium Hidden Lock Partial Denture
 A design using a dual-casting technique is the Ticonium hidden-lock
 This is a two piece casting, the top half, which is the major connector
supporting the direct retainers and other rigid components, is cast first,
 The bottom half, which is the connector between the denture bases, is cast
to the major connector.

48.  The hidden lock is created by mechanical means, and the split between the
two connectors is made possiblxe by the thin oxide shell that forms during
the making of the two sections.
 What appears to be a conventional lingual bar or linguoplate actually is two
bars connected by a movable joint at the midline.

49. 3.The 12 Gauge Chrome Wire Stress Breaker
 The 12 gauge chrome wire stress breaker avoids the complexities of most stress
breaker designs and yet offers many clinical advantages.

52. The advantages of this stress breaker are as
follows:
1. The rigidity of the 12 gauge wire avoids overloading the mucosa.
2. The mucosa is also more evenly loaded
3. It is easy to splint teeth with this design.
4. The fabrication is relatively simple.
5. Repairs are rarely needed and are also simple.

53. 4.Disjunct Dentures (Geissler, Watt 1965 )
 It is a type of the removable partial denture which consists of two
separate parts.
 One part is tooth borne i.e. it contains the direct retainers and indirect
retainers and thus provides retention and stability.
 The second part consists of denture base and thus provides the
support.
Indications:
 when remaining teeth are periodontally compromised

54. Structural details:
 The tooth borne part is a lingual plate and thus provides stabilization for
remaining teeth.
 The tissue borne part is a lingual bar which consists of denture bases along
with the teeth at its terminals.
 When the occlusal forces are applied, most of them directed towards the
tissue borne part.

55. Advantages:
Independent movement between
the tooth supported and tissue
supported parts decreases the
forces on periodontally
remaining teeth.
Disadvantages :
It is technically difficult to
fabricate
Patient may complains of rattling
of the framework during
mastication.

56. Disadvantages of non rigid major connectors:
1. The broken stress denture is usually more difficult to fabricate and therefore
more costly.
2. Vertical and horizontal forces are concentrated on the residual ridge,
in increased ridge resorption. Many stress breakers designs are not well
stabilized against horizontal forces.
3. If relining is not done when needed, excessive resorption of the residual
may result.

57. REVIEW OF LITERATURE

58. STUDY 1 –
LARRY D. CAMPBELL (1977)*
Aim: To evaluate the multiple removable partial denture designs by test
patients.
Conclusions:
 Mandibular lingual bar was chosen over the lingual plate by a 3:1 ratio.
 Metal borders parallel to tongue movement were better tolerated than
those lying transverse.
 In general, patients adapted best to major connectors that covered the
least amount of soft tissues
* J Prosthet Dent 1977;37(5): 507-516

59. STUDY 2 –
HANSEN & CAMPBELL (1985)*
Aim: To evaluate patient acceptance of the sublingual bar when compared to
the linguoplate connector and to determine the preferred design. They were
judged on the parameters of speech, chewing & resting comfort.
Conclusions:
The sublingual bar compared favorably with the lingual plate in patient
acceptance and it should be considered as a viable design alternative when a
lingual plate was not used
* J Prosthet Dent 1985; 54(6):805-809

60. STUDY 3 –
MC. HENRY, JOHANSSON (1992)
Aim: To evaluate the effect of removable partial denture mandibular major
connector design on surrounding gingival tissues.
Results showed a greater increase in mean gingival inflammation with the
control than with the test suggesting that cingulum bar has fewer detrimental
effects on gingival tissues than linguo-plate.
* J Prosthet Dent 1992;68(5):799-803

61. STUDY 4 –
BEN-UR, MIJIRITSKY, GORFIL, AND BROSH (1999)*
Aim : To investigate the design and cross-sectional shape of major connectors
most favorably influencing rigidity and
flexibility.
Conclusion: They concluded that the cross-sectional shape was the most
important factor in achieving rigidity and that the half-pear shaped cross-
section proved to be the most rigid major connector.
* J Prosthet Dent 1999:81(5):526-32

62. STUDY 4 –
PIENKOS, MORRIS, CAMERON AND LOONEY(2007)
 AIM : To determine the minimum major connector diameter that would
provide adequate functional strength; in order to enhance patient comfort &
tissue health.
 Conclusion: It was safe to reduce the lingual bar to a width of either 3 or 2.5
mm
* J Prosthet Dent 2007;97:299-304

63. MODIFICATION IN CONVENTIONAL SWING LOCK CAST PARTIAL
DENTURE FOR REHABILITATING A HEMI MANDIBULECTOMY
DEFECT

64. Swing Lock
Design
Missing key
abutments
Reduced bone
support
Unfavorable
tooth contour
Unilateral
abutments
Gingival
Recession
Retching
Patients
Maxillofacial
defects

65. A COLLAPSIBLE PARTIAL DENTURE FOR A PATIENT WITH LIMITED
MOUTH OPENING
Conroy B, Reitzik M. Prosthetic restoration in microstomia. J. Prosthet. Dent. 26: 324-327,

68. RECENT ADVANCES
1. Use of CAD/CAM technology to fabricate a removable partial denture
framework.

69. 2. PEEK – FOR MAJOR CONNECTORS.
 Strong and lightweight for improved patient comfort
 Digital design matches the patient’s individual anatomy
 The metal-free denture framework is taste-neutral
 Excellent mechanical and chemical properties
 High strength to weight ratio
 Elastic properties similar to human bone
 Zero corrosion rate
 low water absorption
 Radiolucent
 Superior biocompatibility

70. SUMMARY
 For a tooth supported removable partial denture the lingual bar is the
suitable major connector.
 Long span edentulous ridges in which there is posterior abutment and
indirect retention is needed, the lingual plate is indicated.
 When anterior teeth are periodontally treated and needs support and
stabilization, the lingual plate or double lingual bar may be used.
 When the tissue of the floor of the mouth are active and <8mm space
available between tissue and marginal gingiva, a lingual plate is
preferred.

71. CONCLUSION
 Major connectors by uniting the other components of a removable
partial dentures acts like a foundation bringing about bilateral
distribution of forces which depends on the rigidity of the connector.
 Although there are many variations in major connector, a thorough
comprehension of all factors influencing their design will lead to the
best design for each patient.

72. REFERENCES
 McCracken’s Removable Partial Prosthodontics. A.B. Carr, G.P. McGivney, D.T.
Brown. Elsevier.11th ed.
 Stewart’s Clinical Removable Partial Prosthodontics. Rodney D. Phoenix, David
R. Cagna, Charles F. DeFreest. Quintessence 3rd ed.
 Clinical Removable Partial Prosthodontics. Stewart, Rudd, Kuebker. Ishiyaku
EuroAmerica.2nd ed.
 David Henderson. Major connectors for mandibular removable partial
dentures: Design & function. J Prosthet Dent.1973; 30(4): 532-548
 David Henderson : Major connectors for mandibular removable partial
dentures: Design and function. J Prosthet Dent 1973; 30: 530-549.

73.  Carl A. Hansen, Donald J. Campbell : Clinical comparison of two-mandibular
major connector designs: The sublingual bar and the lingual plate. J Prosthet
Dent 1985; 54: 805-808
 Z. Ben-Ur, S. Matalon, I. Aviv : Rigidity of major connectors when subjected to
bending and torsion forces. J Prosthet Dent 1989; 62: 557-562.
 Mansuang Arksornnukit,Hisashi Taniguchi and Takashi Ohyama.Rigidity of
three different types of mandibular major connectors through vibratory
observation.Int J Prosthodont 2001;14: 510-516
 Todd Pienkos, Jack Morris, Peter Gronet, Stephan Cameron and Stephen
Looney: The stength of multiple major connector designs under simulated
loading.J Prosthet Dent 2007;97:299-304
 Robert Walter, James Brudvik, Ariel Raigrodski, Lloyd Mancl, Kwok-Hung
Chung: A comparision of the rigidity of five mandibular major connectors for
partial removable dental prostheses via load deflection.J Prosthet Dent
2010;104:182-190

74. “ No component of a removable partial denture should be added arbitrarily or conventionally.
Each component should be added for a good reason and to serve a definite purpose.”
-McCracken