parts of rpd

1. MINOR CONNECTORS
DR. SILPA ABRAHAM
Ist MDS
DEPT. OF

2. DEFINITION
 The connecting link between the major connector
or base of a partial removable dental prosthesis
and the other units of the prosthesis, such as the
clasp assembly, indirect retainers, occlusal rests,
or cingulum rests.
-GPT 8

3. FUNCTIONS
 Join remaining components of RPD to major
connector
 Transfers functional stress to abutment teeth
 Transfers the effects of retainers, rests and
stabilizes components
-McCracken’s Removable Partial Prosthesis

4. FORM AND LOCATION
 Sufficient bulk to be rigid
 Minor connector which connects axial surface of
an abutment should be located in an embrasure
rather than on a convex surface
McCracken’s Removable Partial Prosthesis

5.  Should conform to interdental embrasure
pass vertically from major connector, gingival
crossing abrupt
Should be thick towards lingual and tapering
towards contact area
McCracken’s Removable Partial Prosthesis

6.  Evidence suggests that gingival attachment loss is
more probable on the proximal aspect, thus minor
connectors located in embrasures cover
susceptible sites.
 - A variation in minor connector design for partial dentures, Radford DR
Waltor JD.Int J Prosthodontics 1993 Jan-Feb;6(1):50-4.

7.  A modification was proposed limited to maxilla.
 Minor connector located on lingual surface of
maxillary abutment tooth.
Advantages:
- ↓ gingival tissue coverage
- Enhanced guidance for insertion and removal
- ↑ stabilization against horizontal and rotational
forces
McCracken’s Removable Partial Prosthesis

8. Disadvantages :
 encroach tongue space
 ↑ potential space for food entrapment
McCracken’s Removable Partial Prosthesis

9.  When minor connector contacts tooth surfaces on
either side of the embrasure, it should taper to the
teeth.
McCracken’s Removable Partial Prosthesis

10. TYPES OF MINOR CONNECTORS
Stewart's Clinical Removable Partial

11. Major Connectors Joining Clasp Assemblies To
Major Connectors

12.  Rigid; sufficient bulk
 Support rests
 Mostly located on proximal surfaces of teeth
adjacent to edentulous areas
 Broad buccolingually; thin mesiodistally
Stewart's Clinical Removable Partial
Prosthodontics

13.  If clasp assembly not on adjacent teeth, lingual
embrasure
 Unobtrusive
 Should never be kept on convex surface of teeth
Stewart's Clinical Removable Partial
Prosthodontics

14. Minor Connectors Joining Indirect Retainers Or
Auxiliary Rests To Major Connectors

15.  Form right angle with major connector
 Junctions gently curved
 Positioned in lingual embrasure
Stewart's Clinical Removable Partial
Prosthodontics

16. Minor Connectors Joining Denture Bases To
Major Connectors

17.  Described as,
 Open construction
 Mesh construction
 Bead, wire or nail head components on a metal base
 Strong
 Rigid
 Minimal interference with arrangement of
artificial teeth
Stewart's Clinical Removable Partial
Prosthodontics

18.  Maxillary arch
 Distal extension; extend entire ridge, cover tuberosity
 Should extend as posterior as possible
Stewart's Clinical Removable Partial
Prosthodontics

19.  Mandibular arch
 Extend 2/3 rd of edentulous arch
Stewart's Clinical Removable Partial
Prosthodontics

20. Open Construction
 Consists of longitudinal and transverse struts;
ladder like network
 Strut placement critical; posterior teeth
arrangement
 This type made using preformed 12guage half
round & 18 guage round wax strips
 Longitudinal struts
 Mandibular arch:
 1 strut buccal to crest of ridge, other strut lingual to crest of
ridge
Stewart's Clinical Removable Partial
Prosthodontics

21.  Maxillary arch
 1 strut buccal to ridge crest,
 Border of major connector 2nd strut
Stewart's Clinical Removable Partial
Prosthodontics

22. Positioning of
longitudinal strut
along crest
Interferes with
placement of
artificial teeth
Predisposes
denture base to
fracture
Stewart's Clinical Removable Partial
Prosthodontics

23.  Transverse struts:
 Positioned to facilitate placement of artificial
teeth
 Adequate room for teeth placement
 Should pass between necks of artificial teeth
Stewart's Clinical Removable Partial
Prosthodontics

24.  Provide relief under gridwork:Adequate
mechanical retention
 This space provided by relief wax placed on cast
before framework fabrication
 About 1mm relief
 Relief should begin 1.5-2mm from abutment
tooth
Removable Partial Denture
Manual, Robert W.Loney

25. Figure 1 Figure 2
Figure 3

26.  Junction of this gridwork should be of strong butt
type joints, with appreciable bulk
 Angles formed should not be >90̊
Removable Partial Denture Manual, Robert
W.Loney

28. INDICATION AND ADVANTAGES
 When multiple teeth are to be replaced
 Provides strongest attachment of acrylic resin to
framework
 Facilitates relining and rebasing of RPD
Stewart's Clinical Removable Partial
Prosthodontics

29. Mesh Construction
 Rigid metallic screen
 Relief and border extension similar to open
construction
Stewart's Clinical Removable Partial
Prosthodontics

30.  Channels pass through connector
↓
permits acrylic resin penetration
↓
resin encirclement
↓
mechanical retention of denture base
Stewart's Clinical Removable Partial
Prosthodontics

31. Drawbacks
Difficulty during
packing of
acrylic resin
Interference with
arrangement of
prosthetic teeth
When restorative
space minimal,
compromised
esthetics
Stewart's Clinical Removable Partial
Prosthodontics

32. CAST STOPS
 Distal extension cases
 Relief -support only at one end
↓
bend when load is applied
 To prevent bending, a small area at free end of
minor connector should contact master
cast→CAST STOP
Stewart's Clinical Removable Partial
Prosthodontics

34. Bead, Nail Head Or Wire Construction
 Used in conjunction with metal denture bases
 Resin attached to free surface of such bases,
retention by encompassing surface projections
 Nail head same manner.
Stewart's Clinical Removable Partial Prosthodontic

35.  Advantage:
 Improved hygiene and enhanced thermal stimulation
 Disadvantage-
 difficulty in adjusting and relining cast metal bases
 Attachment of resin is relatively weak
Stewart's Clinical Removable Partial Prosthodontic

36. FINISH LINES
 The interface between metal and acrylic is
referrred to as finish line.
 If located outer surface of major connector-
external finish line
 If located on inner or tissue surface- internal
finish line

37. Internal Finish Line
 Formation: relief wax placed on edentulous ridge
of master cast prior to duplication
 24-26 guage
 Create elevated area on refractory cast
 Margins of relief wax-establish internal finish
lines
 Margins of wax: sharp and well defined

38. External Finish Lines
 Sharp
 Should be slightly undercut to help lock acrylic
resin to major connector
 Internal angle<90
 Formation: placement of carving of wax during
fabrication

39.  Originate at lingual extent of rest seat
 Continue down lingual aspect of minor
connector occlusal perspective:
 Occlusal perspective:
external lingual sueface

40. MINOR CONNECTORS IN SERVE AS
APPROACH ARM FOR VERTICAL
PROJECTION/BAR-TYPE CLASPS
 Neednot be rigid
 Support direct retainers
 Approaches from apical direction
 Approach arm should display smooth, even, taper
from origin to terminus.

41. REFERENCES
 Stewart’s removable partial prosthodontics
 McCracken’s Removable partial Prosthodintics
 Robert W Loney, removable partial denture
manual
 A variation in minor connector design for partial
dentures, Radford DR Waltor JD.Int J
Prosthodontics 1993 Jan-Feb;6(1):50-4.