Intracoronal Attachments

Intracoronal attachments
1
Presentation by:
Dr. Vanshree Sorathia
MDS Prosthodontist Total no. of slides: 83

Content
• Introduction
• Classification
• Intracoronal attachments
2

Attachments???
A mechanical device for the fixation,
retention, and stabilization of a prosthesis.
- Glossary of Prosthodontics Terms
9
The Glossary of Prosthodontic Terms, 9th edition. J. Prosthet Dent 2017
May; 117(5S):e1-e105. 3

Classification
A. Based upon Method of fabrication and
Tolerance of fit:
Precision Semi-
Precision
H. M. Khuthija Khanam et al. Attachments in prosthodontics: Different
systems of classification: a review. J of Evolution of Med and Dent Sci
2004;3:2278-2748.
4

B. Goodkind & Baker (1973): Precision
Attachment:
Intracoronal
• Resilient
• Non-resilient
Extracoronal
• Resilient
• Non-resilient
2004;3:2278-2748.
5

C. Based primarily on the function of the
attachments:
Feinberg & Feinberg (2002):
o Rigid
o Passive
Becerra & Mac Entee (1987):
A. Intradental
Frictional
Magnetic
B. Extradental
Cantilever
Bar
2004;3:2278-2748.
6

D. Mensor’s classification: Based on
shape, design and primary area of utilization
of attachment.
Coronal Radicular Accessory
1. Intracoronal
2. Extracoronal
3. Telescope stud
(pressure buttons)
4. Bar
• Joints
• Units
5. Auxiliary
A. Screw units
B. Pawl connectors
C. Bolts
D. Stabilizers/
balancers
E. Interlocks
F. Pin/screws
G. Rests
Merrill C, Mensor JR. Classification and selection of attachments.
J Prosthet Dent 1973;29:494-7.
7

E. The "Spectrum of Function: based on
their resilient function(s) or lack of them:
Class
I
Rigid Sterngold type 7 attachment, G/L
attachment, D2.7 attachment
Class
II
Vertical Hader vertical, Preciverteg, Cylindrical
resilient Dallabona
Class
III
Hinge May’s attachment, Miniature Dalbo
attachment
Class
IV
Combination Combination e.g. Octolink attachment,
Standard Dalbo attachment
Class
V
Rotation+
Vertical
O-So male attachment, Micropin female
2004;3:2278-2748.
8

F. Classification by Harold
Prieskel:
1. Intracoronal Attachments
2. Extracoronal Attachments
2004;3:2278-2748.
9

Objectives
o Definition
o Components
o Mechanics of retention
o Friction fit - with friction potential
o Friction fit – without adjustment potential
o Attachments with auxiliary retentive features
o Application – RPD, FPD, Implant
o Contraindication
o Advantages
o Drawbacks
11

o Semi-precision rest
o Selection of abutment
o Selection of type of retainer
o Selection of attachment
o Clinical procedures
o Adjustment of retention
o Remaking of removable prosthesis
o Technical considerations
12

Definition
Any prefabricated or custom-made
attachment for support and retention of a
fixed or removable dental prosthesis; the
patrix and matrix components are positioned
within the normal contours of the abutment
tooth.
- Glossary of Prosthodontics Terms 9
The Glossary of Prosthodontic Terms, 9th edition. J. Prosthet Dent
2017 May; 117(5S):e1-e105. 13

Synonyms
Internal
Attachments
Frictional
Attachments
Parallel
Attachments
Key & Key
Way
Attachments
Slotted
Attachments
HW Prieskel. Precision attachments in dentistry. 3rd ed. Henry Kimpton
1979. 14

Components
Tube
Rein forcing plate
Head
Contact plate
Adjustment slot
HW Prieskel. Precision attachments in dentistry. 3rd ed.
Henry Kimpton 1979. 15

Male
• Patrix
• Flange
• Insert
• Key
• Fitting Point
Female
• Matrix
• Slot
• Crypt
• Keyway
• Receptacle
1979.
16

PRECISION ATTACHMENT
Cross section
Conventional attachment –
T shaped attachments
Modern attachment –
H shaped attachments
Circular cross section
1979. Pg no. 72
17

A. Friction fit B. Mechanical lock
With adjustment potential:
1. Chayes attachment
2. Chrismani attachment
3. Mc Collum
attachment
4. Ancra attachment
5. T - Geschiebe 123
Without adjustment
potential:
1. Round profile
2. Beyeler attachment
Mechanism of Retention
Auxillary
retentive
features. Eg;
Schatzmann
unit
1979. Pg no. 72-77 18

A. Friction fit intracoronal
attachments with adjustment
potential
19

1. Chayes attachment
HW Prieskel. Precision attachments in dentistry. 3rd ed. Henry
Kimpton 1979. Pg no. 72 20
Described in 1906.
Still in production
Adjustability.

2. Stern G/A attachment
Produced in US.
H Shaped – friction.
Several sizes.

3. Crismani attachment
2.8mm
7mm

4. McCollum attachment
Kimpton 1979. Pg no. 73
23
Additional strength.
Adjustment split.
Lower distal extension.
Right and left.

5. Ancra attachment
• ‘H’ shaped profile with external frictional
flange.
• 2 sizes.
• Female unit – high heat or conventional
gold alloys.
• Male unit – slots on either side.
1979. Pg no. 73 24

6. T – Geschiebe 123
1979. Pg no. 74 25
T shaped.
Removable
prosthesis- lingual
bracing arm.

B. Friction fit intracoronal
attachments without adjustment
potential
26

1. Round profiles
1979. Pg no. 77 27

2. Beyeler attachment

C. Mechanical retention – Auxiliary
retentive feature
Minimum of 4mm space
29

1. Crismani units
Wider unit –
wire clip.
Access to
clip.
Female unit –
depressions.
7 mm.

2. Schatzmann series
Spring loaded plunger.
Bulk
Limited application.

3. Stern gingival latch
attachment

4. Microattachments
• Smallest of all intracoronal attachments.
• Modification of G/L system include a unit
with squared lateral surface thereby
allowing the BL dimensions to be reduced.

Factors to be considered for attachments
with auxiliary retentive devices
Bulk
Retention mechanism
Adjustment
Plaque control
Trimming the attachment
1979. Pg no. 77
34

Application
Retainer Connector
Kimpton 1979. Pg no. 77-78 35

Fixed
prosthesis
Implant
supported
Removabl
e
prosthesis
Kimpton 1979. Pg no. 78-91 36

a. Removable prosthodontics
Retainers
1. As a retainer in tooth supported RPDs.
- Bilateral dentures
1979. Pg no. 78 37

- Unilateral dentures – undercut, esthetics in
small gaps. Anterior – lateral incisor. Longer
clinical crown, smaller pulp. Posterior –wider
area coverage, hygiene, splinting.
Kimpton 1979. Pg no. 80-81 38

2. Distal extension partial dentures
- Precise path of insertion.
- Strong attachment & lingual bracing arm –
importance????
- Splinted abutment.
Kimpton 1979. Pg no. 82-84 39

o Bilateral distal extension
- Cantilevered artificial tooth.
- Advantages???
- Torque.
- Natural teeth.
Kimpton 1979. Pg no. 85-88 40

o Unilateral distal extension spaces
- Extensive tooth preparation v/s clasp
retained dentures.
- Extensive restoration of abutment.
- Space on opposing side
- Lower anterior teeth – premolar; bulk.
- Telescopic crown – no space; gingiva.
Kimpton 1979. Pg no. 85-88
41

o Divergent abutment teeth with high survey
lines –parallel path of placement.
o As a retainers in tooth supported over
denture.
Kimpton 1979. Pg no. 88-89 42

b. Fixed prosthodontics
Connectors
o Connector – long span bridges.
o Questionable prognosis of abutment.
o Malaligned abutments.
Kimpton 1979. Pg no. 88-89 43

c. Implant prosthesis
o Implant supported overdentures.
1979. Pg no. 88 44

Contraindications
Poor periodontal support
Poor crown to root ratio
Poor oral hygiene habits
Abnormally high carious rate
Inadequate space
Compromised endodontic and restorative conditions

Advantages over clasp
1. Esthetics
Kimpton 1979. Pg no. 78-80 46

2. Retention unaffected by crown
contour
Kimpton 1979. Pg no. 78-80 47

3. Reduced bulk
Kimpton 1979. Pg no. 78-80 48

4. Stability
Kimpton 1979. Pg no. 78-80 49
5. Elimination of food
stagnation

6. Stress breaker
Kimpton 1979. Pg no. 78-80 50

Drawbacks over clasps
Extensive
preparation of
abutment
Cost and time
Crown length
& pulp height
Difficulty
Handling by
patient
Kimpton 1979. Pg no. 78-80 51

SEMI-PRECISION REST
• Tapered sides.
• Provides occlusal support but bracing
action is less.
• If abutment crowned – guide plane
incorporated & rest seat can be deepened.
Bracing arm – retention
Rest – bracing action
52

Louis Blatterfein 1969
Design from four aspects:
Proximal
form
Occlusal
form
Gingival
floor form
Proximal
surface
placement

Proximal form: lateral force control.
>5⁰
>3mm
Depth Taper

Occlusal outline: controls the amount of
rotation.
>3mm

Gingival floor form: resistance to
displacement.

Proximal surface placement- lingual arm:
Controls the amount of rotation.
Engages a dimple on lingual surface of
prosthesis.

Thompson dowel
Kimpton 1979. Pg no. 98-99 58

Prefabricated retentive devices
Tach E Z Unit – spring loaded plunger
C L Unit – spring clip

Selection of abutment
Factors:
• Condition of abutment teeth
• Number of the abutment teeth
• Location of the abutment teeth
• Periodontal condition – Crown root ratio –
Periodontal support
• Pulpal status – Vitality of the pulp –Size of
the pulp chamber

Maximum attachment
length 6-7 mm
Minimum attachment
length 4mm
Inadequate attachment
length < 4mm

Buccolingual space requirement
Adequate space between the pulp and the
normal contour of the tooth

Selection of type of retainer
• Full coverage crown
• Inlays or pin retained

Selection of attachment
EM attachment gauge (Matsuo (1970)
75 mm in length
Red 3-4mm
Yellow 5-6mm
Black 7-8mm
1979. Pg no. 99
65

105 attachments, 30 points of information

Clinical procedures
1. Abutment preparation – wide shoulder
with box in prosthesis. Also consider lingual
bracing arm. 0.5mm clearance.
67

2. Impression procedure:
o Reversible hydrocoloid
o Silver plated Polyeter or Mercaptan rubbers
- More space of trays
- Closely adapted custom trays
- Copper ring technique – Duralay resin coping
- Impression plaster.
3. Facebow transfer and jaw relation record →
mounting of master cast.
4. Metal framework trail.
Kimpton 1979. Pg no. 100-101
68

Fixed restorations – error – prosthesis may
not slide into place.
Casting sectioned with disc
Locating impression made
Casting of concerned prep removed,
remainder metal framework placed
intraorally
Pickup impression made – polysulphide or
mercaptan rubbers - best
69

Removable partial denture – modified
impression procedure.
Initial impression same
Female component casted and accuracy
checked on abutment
Rigid acrylic resin tray spaced over casting
but closely adapted to denture bearing
areas
Pickup impression made with casting
carrying female component – polysulphide
70

Cast is rearticulated and denture
framework made
Altered cast technique
Make denture framework with closely
adapted acrylic resin base over edentulous
ridge
Displacement impression made (fluid wax
or ZOE – with casting (female component)
and framework
Reconstitute cast after sectioning

Large restorations – temporary non setting
cement → trail restoration.
Precise location may be disturbed – all
component placed before cement
hardens.
Removable prosthesis – not to remove
dentures for 24 hours.

Next visit – Occlusion & Adaptation. If
error – rebase it immediately.
Path of insertion & interdental brush for
female component.
Follow up period – 1 week, 1 month, 6
months.

Adjustment of retention
Stern G/L attachment Special adjustment
instrument
European attachments Spring replacement or
retaining clip adjustments
Stern G/A and McCollum
units
Annealed razor blade
Chayes and Crismani Small jeweller’s screwdriver
Flange section open slightly Oversized slot
74

Remaking of removable
prosthesis
Problem – reproducing the slots of female
section of attachment.
Bartlett 1966 – method of using mercaptan
rubber base.
1979. Pg no. 102 75

Technical considerations

Kimpton 1979. Pg no. 104-106 78

Case reports
Makkar S et al. Attachment Retained Removable Partial Denture: A Case Report. Int.
Journal of Clinical Dental Science 2011;2:38-41. 79

Case reports
Edward Feinberg E. Precision Attachment Case Restoration With Implant Abutments: A
Review With Case Reports. Journal of Oral Implantology2011;37:489-498 80

References
1. HW Prieskel. Precision attachments in dentistry. 3rd
ed. Henry Kimpton 1979.
2. The Glossary of Prosthodontic Terms, 9th edition. J.
Prosthet Dent 2017 May; 117(5S):e1-e105.
3. H. M. Khuthija Khanam et al. Attachments in
prosthodontics: Different systems of classification: a
review. J of Evolution of Med and Dent Sci
2004;3:2278-2748.
4. Merrill C, Mensor JR. Classification and selection of
attachments. J Prosthet Dent 1973;29:494-7.
82

5. Hema Kanathila et al. An insight into various
attachments used in prosthodontics: A review.
International Journal of Applied Dental Sciences
2018; 4(4): 157-160.
6. Koper A. An intracoronal semi-precision retainer
for removable partial dentures-The Thompson
dowel. J Prosthet Dent 1973;30:759-68.
7. Arti et al. Precision Attachments in
Prosthodontics: A Review. International Journal of
Preventive and Clinical Dental Research
2018;5(2):34-39.
8. Becerra G, Macentee M. A classification of
precision attachments. J Prosthet Dent
1987;58:322-7. 83

9. Burns DR, Ward JE. A review of attachments for
removable partial denture design: part 1.
Classification and selection. Int J Prosthodont.
1990;3:98-102.
10.Burns DR, Ward JE. A review of attachments for
removable partial denture design: part 2.
Treatment planning and attachment selection. Int
J Prosthodont 1990;3:169-74.
11.Herbert T. Shillinburg. Fundamentals of fixed
prosthodontics. 4th edition, Quintessence
Publishing Co, 2012.
12.Rosenstiel SF, Land MF, Fujimoto J.
Contemporary fixed prosthodontics. 5th ed. St.
Louis: Elsevier; 2016. 84

Intracoronal Attachments

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Intracoronal Attachments

Similar to Intracoronal Attachments (20)

More from Dr. Vanshree Sorathia

More from Dr. Vanshree Sorathia (10)

Recently uploaded

Recently uploaded (20)

Intracoronal Attachments