tooth supported Overdentures

OVERDENTURES
PRESENTED BY –
Dr. PRAJAKTA BALI GIR
II YEAR MDS
DEPARTMENT OF PROSTHODONTICS, CROWN &
BRIDGE AND ORAL IMPLANTOLOGY, DDCH, UDAIPUR
1

CONTENTS
• INTRODUCTION
• HISTORY
• RATIONALE FOR OVERDENTURES
• REQUIREMENTS OF OVERDENTURE
• ADVANTAGES AND DISADVANTAGES OF OVERDENTURES
2

CONTENTS
• INDICATIONS AND CONTRAINDICATIONS OF
OVERDENTURES
• PATIENT SELECTION AND ABUTMENT SELECTION
• TYPES OF OVERDENTURES
• CLASSIFICATION OF OVERDENTURES
• ATTACHMENT SYSTEM
3

CONTENTS
• IMPRESSION PROCEDURES
• DELIVERY AND POST INSERTION CARE
• SUMMARY
• REVIEW OF LITERATURE
• REFERENCES.
4

INTRODUCTION
5

• The transition from natural teeth to suddenly becoming edentulous and
wearing dentures is often a traumatic, physical and psychologic experience
for the patient.
• Frequently, weeks pass before the patient with new dentures can accept them
as an integral part of his natural appearance and function.
• Many times, the patient believes that he has lost his youth, his previous
phonetic ability, and his senses of taste, smell, and tactile discrimination.
6
INTRODUCTION
Sensory perception in overdenture patients
William D. Kay, and Marshall ,. Aber,

• Covering the hard palate and other tissues, blocks vast regions of nerve
receptors that respond to pain, pressure, and thermal changes.
• Although these receptors do not become completely afunctional, the rigidity
and the insulating effect of the acrylic resin, porcelain, and metal materially
alter their function.
• Although it is impossible to eliminate all adverse neurologic effects, the use
of tooth-supported complete dentures, commonly called overdentures,
makes possible a high degree of tactile discrimination.
7
INTRODUCTION

• The most commonly used procedure for overdentures requires periodontal
therapy for the remaining teeth, possible endodontic therapy, reduction of
clinical crowns, and placement of gold copings or functional attachments.
• The prosthesis is constructed so that the retained teeth lend support, stability,
and, in some instances, retention to the denture.
8
INTRODUCTION

• Zamikoff’ has defined the overdenture as a complete denture supported by
soft tissue and a few remaining natural teeth that have been altered to permit
the denture to fit over them.
• In addition to the readily apparent advantages of added support, stability,
retention, and preservation of bone, the ability of the overdenture to improve
tactile sensory perception has received increased attention.
9
INTRODUCTION

DEFINITION
• GPT 1999,
1. Overdenture is defined as a removable partial denture or a
complete denture that covers and rests on one or more remaining
natural teeth, the roots of natural teeth, and/or dental implants.
2. A prosthesis that covers and is partially supported by natural
teeth, natural tooth roots, and/or dental implants – called also Overlay
denture, overlay prosthesis, superimposed prosthesis.
10
INTRODUCTION

DEFINITION
• Heartwell,
A tooth supported complete denture is a dental prosthesis that
replaces lost or missing natural dentition and associated structures of
the maxilla and/or mandible and receives partial support and stability
from one or more modified natural teeth.
11
INTRODUCTION

DEFINITION
• Overlay is a term used to describe a removable partial denture that
has a metal casting or an acrylic resin extension on or over the
occlusal or incisal surfaces of natural teeth.
12
INTRODUCTION

SYNONYMS
• Biologic denture
• Hybrid denture
• Telescopic denture
• Overlay denture
• Onlay denture
• Tooth supported dentures
• Super imposed denture.
13
INTRODUCTION

GOALS
14
INTRODUCTION
MAINTAINS TEETH
AS PART OF THE
RESIDUAL RIDGE
DECREASE IN THE
RATE OF
RESORPTION
RETAINING THE
PROPRIOCEPTION
More support
Withstands more occlusal load
Retention improve
An increase in the patients
manipulative skills in handling
the denture
Alveolar bone exist as a support
For teeth

HISTORY
15

• LEDGER (1856) prescribed a prosthesis resembling an overdenture. His
restorations were referred to as plates covering fangs (teeth)
• EVANS (1888) described a method for using roots to retain restorations after
intentional devitalisation of the roots.
• ESSIG (1896) described a telescopic‐like coping.
16
HISTORY

• 1906–WILLIAM HUNTER put forward his focal sepsis theory and this dealt
a great blow to the overdenture mode of treatment. The main point of
contention was that the exposed roots act as foci of infection.
• 1916‐PEESO was employing removable telescopic crowns. Later on, the bar
type of construction was developed.
17
HISTORY

• MILLER (1958) published his classic article where the retention of
previously unusable teeth and their advantageous use in overdenture
treatment was explained as a basic tenet in management.
• Prieskal (1968) described various commercially available overdenture
attachments
18
HISTORY

RATIONALE FOR
OVERDENTURES
19

MAINTAINING SENSITIVITY OF ANTERIOR TEETH:
• Sensory input from the periodontal receptors is one of the major
determinants of masticatory function, and the roots of the teeth offer more
discrete discriminatory input than does the oral mucosa. Retention of natural
teeth for an overdenture preserves some of the sensory input from the
periodontal receptors, which is more precise than that able to be obtained
from the oral mucosa.
20
RATIONALE

MAINTAINING SENSITIVITY OF ANTERIOR TEETH:
• Kawamura (1964), Grossman (1964), and Grossman and associates (1965)
agreed that the sensitivity in the anterior part of the mouth, particularly the
periodontal ligament of the anterior teeth, tongue tip, and mucosa, was acute.
• There is a greater concentration of sensory receptors in the anterior part of
the mouth (Kawamura, 1964), and these signals from the periodontal and
mucosal receptors are important in controlling and determining biting force.
21
RATIONALE

DIMENSIONAL PERCEPTION:
• Dimensional perception is the discrimination of the different thickness of
objects between the occlusal surfaces of the teeth. Kawamura and Watanabe
(1960) found that patients with natural dentition could discriminate
differences at the 2 mm range better than those with artificial dentures.
These findings emphasized the importance of conservative procedures and
the importance of the retention of natural teeth.
22
RATIONALE

CANINE RESPONSE:
• Kruger and Michel (1962) said that the canines have more neurons than any
other teeth. So, it acts as very important proprioceptive organ which can lend
support to the retention for the overdenture.
23
RATIONALE

DIRECTIONAL SENSITIVITY:
• Jerge (1963, 1965) reported that the receptors in the periodontal ligament
were directionally sensitive. He said that the receptors are arranged around a
tooth in such a way as to respond to pressure regardless of the direction
from which it is applied. Directional sensitivity is one of the most important
elements in the interaction of the masticatory system.
24
RATIONALE

DIRECTIONAL SENSITIVITY:
• It means that the periodontal receptors have a functional individuality and
that the relationship of the tooth to its periodontal ligament is highly
important from a sensory standpoint. Therefore, teeth should be retained for
use with an overdenture to preserve the directional sensitivity.
25
RATIONALE

PROPRIOCEPTION AND SALIVARY SECRETION:
• Kapur and Collister (1970) studied food texture discrimination and
concluded that the periodontal receptors played an indirect role in the
masticatory salivary reflex by regulating the range and type of the
masticatory stroke. They stated that absence of the periodontal ligament in
denture wearers appeared to result in impairment of the mechanism
regulating parotid gland stimulation during mastication.
26
RATIONALE

PERCEPTION OF NONVITAL TEETH:
• The majority of natural teeth used to support overdentures are devitalized
and treated endodontically. Perceptual studies showed that vital and
devitalized teeth had equal sensory input capabilities (Stewart, 1927; Adler,
1947).
27
RATIONALE

PERCEPTION OF TEETH WITH REDUCED ALVEOLAR
SUPPORT:
• Often teeth selected for use with overdentures may have lost bone support.
The studies showed that the tooth still had a proprioceptive input capability
even though much of the bone support was lost.
28
RATIONALE

DECREASE OF PERCEPTION IN OLDER INDIVIDUALS:
• There is generalized decrease in perception as age increases and the use of
an overdenture is an attempt to retain every possible sensory element at the
time the patient may experience a generalized decrease in the sensory
capacity.
29
RATIONALE

REQUIREMENTS
30

MAINTENANCE OF HEALTH
• The most important aspect of the overdenture is the maintenance of the
health of the underlying tooth structure, without which the overdenture
cannot sustain.
• Teeth that are to be utilized as overdenture abutments must first be evaluated
for their periodontal condition.
31
REQUIREMENTS

MAINTENANCE OF HEALTH
• Exhaustive studies have shown that bone loss occurs only in the presence of
plaque
• Plaque accumulation can be prevented by proper home care by the patient,
which is possible only if pocket depths and bony defects have first been
removed.
32
REQUIREMENTS

REDUCTION IN CROWN-TO-ROOT RATIO
• The reduction of the crown has an immediately favorable effect on tooth
mobility because of the decrease in the length of the lever arm delivering the
torque to the mobile tooth.
33
REQUIREMENTS

BASAL SEAT TISSUE
• The tissue covering the remaining basal area should be treated and
expected to respond quite similarly to the tissue under a complete or partial
denture base.
• A well-fitting base is essential to distribute the load over as wide an area as
possible.
• Intimate tissue contact is also necessary to prevent food and plaque
accumulation under the base.
34
REQUIREMENTS

SIMPLICITY OF CONSTRUCTION
• The appliance should be relatively simple to construct and maintain.
• In many cases, due to lack of available space, sections of the overdenture
base are quite thin.
• If metal reinforcement is not used, fracture of the base and prosthetic teeth is
common.
35
REQUIREMENTS

EASE OF MANIPULATION
• The base should be easily manipulated by the patient.
• Frequently, with the use of retaining devices, the overdenture becomes a
struggle for the patient to insert and remove.
36
REQUIREMENTS

EASE OF MANIPULATION
• This should not be the case, because an unwanted force could seriously
damage the base or the abutment teeth.
• Therefore, consideration must be given to the type of overdenture used and
to the coordination of the patient in selecting the course of treatment.
37
REQUIREMENTS

ADVANTAGES AND
DISADVANTAGES
38

ADVANTAGES
• Preservation of alveolar bone
• Preservation of proprioceptive
response
• Support
• Retention
• A simple approach to the
problem patient
• Periodontal maintenance
• Patient acceptance
• Convertibility
• Harmony of arch form
39
ADVANTAGES

DISADVANTAGES
• Caries susceptibility
• Bony undercuts
• Overcontour and undercontour
• Encroachment of the interocclusal distance
• Esthetics
• Periodontal breakdown of the abutment teeth
40
DISADVANTAGES

INDICATIONS AND
CONTRAINDICATIONS
41

INDICATIONS
• Younger the patient greater the indication
• In situations where retention is difficult to obtain e.g Xerostomia
• Absence of alveolar residual ridge, Loss of maxilla or partial loss of
mandible, Congenital deformity (i.e. Cleft palate)
• For patients with poor prognosis for complete dentures
42
INDICATIONS

• High palatal vault and ridge slope
• Poorly defined sublingual fold space
• In class III tongue patients
• Knife edge ridge
• When pronounced vertical overlap is required to produce the desired
esthetic result.
43
INDICATIONS

• Unilateral overdenture can be given to provide good function and esthetics
when a large amount bone and soft tissues have been lost on one side of the
arch
• Patient with badly worn out teeth.
• When complete denture will be opposed by retained mandibular anterior
teeth preventing combination syndrome.
44
INDICATIONS

CONTRAINDICATIONS
• Uncooperative: Under motivated patients
• Psychologically some patient cannot accept removable prosthesis
• Mentally and physically compromised
• When patient cannot economically afford
45
CONTRAINDICATIONS

Contraindications for Periodontally involved teeth
Class III Mobility
Uncorrectable soft tissue and osseous defects
Failure to establish sufficient zone of attached gingival
46
CONTRAINDICATIONS

Contraindications for Endodontically involved teeth
Vertical fracture
 Mechanical perforation of root
 Broken instrument
 Horizontal fracture of root below bony crest
47
CONTRAINDICATIONS

PATIENT AND
ABUTMENT SELECTION
48

CLINICAL EVALUATION
• It is very difficult to make a correct diagnosis to determine if the
overdenture is indicated for the patient or the problems can be solved by
alternative techniques.
• This is ascertained by taking a proper history of the patient’s medical
background and past dental history.
• The past dental history indicates the patients experience with previous
removable appliances and his attitude towards the treatment.
49
PATIENT
SELECTION

• Study casts accurately mounted on an articulator show the occlusal
relationship of the teeth and arches, the vertical spaces between arches
and location of bony undercuts.
• They also help in determining the amount of tooth reduction required, the
types of coping and often the types of attachments that can be used for
particular condition.
50
PATIENT
SELECTION

• Accurate study casts can also be used for fabrications of interim
overdentures when necessary.
• Radiographic examination is done to evaluate presence of pathological
conditions, presence of retained roots, bone loss, root curvatures, root
canals are noted.
51
PATIENT
SELECTION

TREATMENT PLANNING
• The patient who has only few retainable natural teeth may present difficult
treatment questions for the dentist. Johnston and associates (1965) stated that
a bridge is indicated whenever there are properly distributed and healthy teeth
to serve as abutments, provided these have suitable crown-root ratio and that
after radiographic, diagnostic cast and oral examinations seem capable of
sustaining the additional load.
52
ABUTMENT
SELECTION

• When indicated, fixed partial dentures are treatment of choice.
• A few retainable teeth generally are scattered throughout the arch, and
invariably they are involved periodontally with unfavorable crown-root
ratios, the overdenture option should be considered.
53
ABUTMENT
SELECTION

• The treatment planning include evaluation of all potential abutments for:
– Periodontal status
– Endodontic status
– Caries management
– Positional considerations
– Economics
54
ABUTMENT
SELECTION

PERIODONTAL STATUS:
• It is best to select abutments that are in an acceptable state of periodontal
health .
• Abutment should have minimum mobility, have adequate bone support and
be amenable to any indicated periodontal treatment.
• Periodontal pockets, inflammation, bony defects and poor zone of attached
gingiva must all be eliminated before commencing the treatment.
55
ABUTMENT
SELECTION

• A common periodontal requisite with overdenture abutment teeth is that an
adequate zone of attached gingival is mandatory.
• This can be accomplished with periodontal surgery utilizing either a free
gingival graft or apically repositioning split thickness flap.
56
ABUTMENT
SELECTION

• This results in a band of attached gingiva adjacent to abutment tooth.
• It should be understood that reduction of clinical crown-root ratio will be
favorable in reducing any existing mobility.
57
ABUTMENT
SELECTION

ENDODONTIC CONSIDERATIONS:
There are two advantages to treating the abutment teeth endodontically;
• (a) the crown-root ratio can be made more favorable, and
• (b) the reduction of the clinical crown provides an interocclusal distance
more favorable to placing the artificial tooth in an esthetically acceptable
position and, at times, in a more favorable occlusal relation to the opposing
teeth.
58
ABUTMENT
SELECTION

CARIES MANAGEMENT:
• The presence of a high caries index and the creation of a situation that will
easily promote a caries environment are two of the most devastating sequelae
to improper overdenture patient selection.
• An active caries process can lead to a recurrence of in unprotected abutment
teeth or gingival to coping margins and this can lead to failure of the
overdenture.
59
ABUTMENT
SELECTION

POSITIONAL CONSIDERATIONS:
• Preference for anterior over posterior teeth because alveolar ridge of
anterior teeth appears to be more vulnerable to reduction compared to
posterior alveolar ridge.
• Two teeth in each quadrant presents an ideal situation in where stress is
distributed over a rectangular area.
• Two canines and two second premolars present an ideal situation.
60
ABUTMENT
SELECTION

• The tripod is next most favorable form for support and stability.
• The use of two teeth in each arch or one tooth in one arch has met with
satisfactory results.
• Morrow recommends to use isolated teeth as abutments because they return
to healthy state readily and are easier for the patient to maintain hygiene.
61
ABUTMENT
SELECTION

• The upper anterior teeth should be retained if opposed by natural lower
anterior teeth to prevent the destruction of the anterior maxillary ridge when
utilized in a maxillary overdenture.
• Mandibular cuspids are most often utilized since they are usually last tooth
to fall.
62
ABUTMENT
SELECTION

63

ECONOMICS:
• Endodontic treatment, cast copings, attachments and overdenture itself may
workout expensive, so economics of the patient should be considered.
64
ABUTMENT
SELECTION

TYPES OF
OVERDENTURES
65

• TRANSISTIONAL OVERDENTURES
• OVERDENTURES FOR CONGENITAL AND ACQUIRED DEFECTS
• IMMEDIATE REPLACEMENT OVERDENTURES
• DEFINITIVE OVERDENTURES
• IMPLANT OVERDENTURES
• PARTIAL OVERDENTURE
66
TYPES

TRANSISTIONAL OVERDENTURES
• A Transitional or interim overdenture is made from an existing removable
partial denture, the patients own teeth or from both.
• Frequently, the entire procedure can be done while the patient waits, or part
of it can be done before the extraction visit.
• The objective is to do the most for the patients with the least of trauma.
67
TRANSISTIONAL

• Advantages:
– Less expensive
– Smooth transition
– Minimal interference with function and appearance
• Disadvantages
– Border extension, esthetics, occlusion, support and stability of the R.P.D.
often are inadequate, particularly after many years of use, making
satisfactory conversion difficult.
– Weaker overdenture
68
TRANSISTIONAL

OVERDENTURES FOR CONGENITALAND ACQUIRED
DEFECTS:
• Many patients with congenital and acquired defects cannot be treated
successfully with orthodontic or surgical therapy, nor can they be treated
with conventional procedures – either fixed or removable.
• However there has been a high degree of success in treating these patients
with complete dentures over their existing teeth.
69
DEFECTS

• The congenital defects most frequently treated with over dentures are:
Cleft palate
Micordontia
Oligodontia
Cleidocranial dystosis
Class III patients with prognathic mandible.
• The acquired defects most frequently treated by this usually results from
accidents, disease or misuse.
70
DEFECTS

IMMEDIATE REPLACEMENT OVERDENTURES
• An immediate overdenture is an overdenture constructed for insertion
immediately after the removal of natural teeth.
• It may be used as an interim prosthesis.
• The immediate overdenture enables a dentist to use a simplified
construction technique that allows flexibility in planning treatments as
requirements change.
71
IMMEDIATE

• Many times with good oral hygiene and regular professional supervision
an immediate overdenture may have a long life.
• Sometimes, it can be a prognostic aid before a more comprehensive
overdenture procedure.
• If prognosis is poor and response to treatment is poor then immediate
denture can be converted into a serviceable complete denture.
72
IMMEDIATE

DEFINITIVE OVERDENTURES
• These dentures are usually constructed at least 6 months following
extraction of last teeth and preparation of overdenture abutments.
• By the time such dentures are made , the edentulous ridges should be
matured and the gingival margins firmly established.
• Dentures of these type may involve metal bases and attachments.
73
DEFINITIVE

PARTIAL OVERDENTURE
• Many times single or multiple teeth can be used in conjunction with a
removable partial denture.
• The use of an overlaid tooth that might otherwise be extracted to give
posterior support to a distal extension base or to provide anterior support for
a large anterior supply on a partial denture renders obvious support
advantage.
74
PARTIAL

IMPLANT OVERDENTURE
• A wide variety of implant types and procedures have been used with an
overdenture as the means of a final restoration.
• The osseointergrated approach of implants with its use of titanium metal and
rather sophisticated techniques of placement has proven to be viable and
worthy procedure.
• Although it is used mostly with fixed type of prosthesis, on occasion single
fixtures are placed on each side of the midline and an overdenture is
fabricated over fixture.
75
IMPLANT

CLASSIFICATION OF
OVERDENTURES
76

• HEARTWELL:
– I . Noncoping
– II. Coping
– III. Attachments
77
CLASSIFICATION

NON-COPING
• Selected root abutments are reduced to a coronal height of 2 to 3 mm and
then contoured to a convex or dome-shaped surface.
• This type of surface will minimize lateral occlusal stresses
• Most teeth require endodontic therapy and in the final step are prepared
conservatively to receive an amalgam or composite type restoration
78
NON-COPING

• It is the simplest, cheapest and least space-consuming option.
• It is ideal during maturation of the edentulous ridges.
• It can also be used to evaluate the questionable abutments.
• It should not be used on a long-term basis where natural teeth are in direct
opposition – possibility of longitudinal root fracture.
79
NON-COPING

COPING
• Cast metal copings with a dome-shaped surface and a chamfer finish line at
the gingival margin are fabricated and cemented.
• A coping fitted to a prepared abutment is called a primary coping.
• The sleeve, or coping, that fits over this primary coping is referred to as a
secondary coping.
80
COPING

• There are four basic types of primary copings:
1. Long copings (6-8 mm).
2. Medium copings (4-6mm).
3. Medium-short copings (2-4 mm).
4. Short copings (1-2 mm).
81
COPING

• The long coping is an excellent restoration, applicable to many overlay
techniques.
• It may be used simply to provide stability and retention under a telescopic
overdenture.
• for vital teeth
82
LONG
COPING

• Medium sized copings may be used with vital teeth where the pulp has
receded or with non vital teeth having adequate bone support.
• Medium sized copings are not generally designed as individual copings for
retention of the overlay prosthesis.
• They are generally connected with some type of bar attachment. Or, they
may also be used with auxiliary plunger or pressure button attachments.
83
MEDIUM
COPING
Abutment preparations
for medium copings
Medium copings

• They are conical with greater taper on all surfaces, particularly the facial
surface when used with bar attachments.
• If used with a plunger button attachment, the surface engaged by the
plunger is flattened.
84
MEDIUM
COPING
With bar attachments To engage plunger
Studs cantilevered

• Medium short copings are indicated for nonvital teeth; where a more
favorable crown root ratio is desired than that possible with medium or
long copings.
• This coping form (and preparation) is indicated when:
• it is difficult to obtain auxiliary retention of the coping on the abutment
with a dowel or parallel pins (the proximal walls of the preparation should
be very closely parallel for maximum frictional fit of the coping);
• numerous neighboring abutments are to be splinted, thus permitting better
embrasure formation than possible with very short copings; used with bar
attachments. DEPARTMENT OF PROSTHODONTICS, CROWN &
85
MEDIUM
SHORT
COPING

• DOWEL DESIGNS
• There are mainly 5 categories:
1. Customised cast dowel
2. Prefabricated resin patterns
3. Prefabricated metal dowels
4. Threaded dowels
5. Dowel systems
86
MEDIUM
SHORT
COPING

CUSTOMIZED CAST DOWELS
• When a dowel and coping are waxed together and cast as a unit the
discrepancy is the same as when making an inlay and crown in the same
casting.
• If the expansion for the coping were sufficient, the dowel would be
oversized, the coping could not seat, and the dowel could fracture the root
during either try-in or cementation because of the wedge effect and the
hydrostatic pressure of the cement.
87
DOWELS

• This factor can be reduced by preparing cement - release groove down the
long axis of the dowel.
• If the dowel were undersized, the coping would seat properly, but the
dowel would be retained by cement only.
88
CUSTOMISED
CAST
DOWEL

PREFABRICATED RESIN PATTERNS
• The prefabricated dowel patterns are provided with a matched set of burs
for preparing the dowel space.
• The cross sectional strength of a pattern dowel is considerably less than that
of a prefabricated metal dowel of the same size, for the metal dowels are
drawn from a high fusing alloy, different than that used for the copings, and
do not have the potential porosity and fracture of a cast dowel.
89
DOWELS

PREFABRICATED METAL DOWELS
• The prefabricated metal dowels have a big advantage over the two previous
systems because of the exact fit and high metallurgic strength in the cross
sectional area; they require minimal enlargement of the canal space and
strengthen the tooth rather than weaken it.
• The prefabricated metal dowels have matched sets of burs for exact fit of
the preparation.
90
DOWELS

• The dowels are machined from high-fusing wrought metal that is specially
alloyed for dowel usage.
• Most of these dowels have cement release grooves, which avoid the
possible risk of incomplete seating or root fracture during cementation.
91
PRE
FABRICATED
METAL
DOWEL

THREADED DOWELS
• Threaded dowels provide mechanical fixation in addition to cementation.
• The VK and Kurer systems offer excellent retention with the threading.
92
DOWELS
Schenker step pivot
(European).
V K and Kurer
system

• Short copings are fabricated to conform to the curvature of the alveolar
ridge, with a very low profile.
• They are indicated for maximum favorable crown-root ratio.
• Such short copings are particularly suited to various types of stud
attachments, but may also be used effectively with many forms of bar
attachments.
93
SHORT
COPING

ATTACHMENTS
• The attachments essentially increase the crown-root ratio and then torque.
• Here, low caries index, proper home care, periodontal health and inter ridge
distance are absolutely necessary.
• Mechanical stabilization can be improved by incorporating the use of
attachments and retentive devices with the basic principles of complete
denture design.
94
ATTACHMENTS

BASIC PROSTHETIC DESIGN
• It is important to realize that the causes of failure inherent in the complete
denture prosthesis are not overcome by using attachment fixation.
• The use of attachments does not authorize the abandonment of basic
principles.
• Failures of the hybrid prosthesis (overdenture with attachment fixation)
occur not because of the attachments but because of improper attachment
selection and failure of the dentist to develop maximum denture base
extension, atmospheric seal, and, for mandibular bases, coverage of the
retromolar pad.
95
ATTACHMENTS

• Availability of the proprioceptive elements in the attachment retained
overdenture permits use of gnathologic procedures.
• Use of the attachment introduces another factor in basic prosthetic design,
that is, the demand for an exact attachment prosthesis relationship.
• For each type of attachment the demand differs, depending on the
availability or desirability of resiliency and the overall adaptation of the
denture base over the soft and hard tissues of the denture bearing area.
96
ATTACHMENTS

ATTACHMENT SYSTEMS
97

• ATTACHMENTS CAN BE CLASSIFIED ACCORDING TO SHAPE,
DESIGN, AND PRIMARY AREA OF USE AS FOLLOWS: (Mensor)
• Coronal
1. Intracoronal attachments
2. Extracoronal attachments
• Radicular
3. Telescope stud attachments (pressure buttons)
4. Bar attachments
a. Joints
b. Units
98
ATTACHMENTS

• Accessory
– 5. Auxiliary attachments
a. Screw units
b. Pawl connectors
c. Bolts
d. Stabilizers/balancers
e. Interlocks
f. Pins/screws
g. Rests
99
ATTACHMENTS

STUD ATTACHMENTS
• Most of the stud-type attachments can be considered to be "snap fasteners"
and are the simplest in concept.
• They can be resilient or non resilient.
• They can also be divided into 2 groups :
– Extraradicular
– Intraradicular
100
ATTACHMENTS

• EXTRARADICULAR :
• Male element is fixed to the abutment and projects from the root surface of
the preparation; the female component is attached to the denture.
• Attachment of male component to the female component provides the
retention.
• The male parts are available as:
○ Prefabricated metal post – cemented directly to the root
○ Prefabricated resin patterns – which is cast and cemented to the root
101
ATTACHMENTS

• EXTRARADICULAR :
• The female component is also termed as ‘retentive anchor’ and may be
made in metal or plastic and is in the form of an ‘O’-ring or matrix
102
ATTACHMENTS

DEPARTMENT OF PROSTHODONTICS, CROWN & BRIDGE AND ORAL
IMPLANTOLOGY, DDCH, UDAIPUR
103
Guttapercha is
removed
with Peeso reamer.
Sequential drilling is
performed with
appropriate drills to
enlarge the post space
Prepared post space.
The final drill should
correspond to the shape
and size of attachment
Male component
housing is
cemented on abutment
Female
component attached to
denture with
autopolymerizing acrylic
Female component with
housing is positioned on
male component prior to
attaching it to denture.
Male component is
attached to
housing.

104

• INTRARADICULAR:
• Male element forms part of the denture base and engages a specially
produced depression within the root contour
• Indicated in situations of reduced interocclusal space.
• Examples: Logic and Zest attachments.
105
ATTACHMENTS

106
Zest attachment. (1)
Male component
attached to denture (2)
female component fixed
on abutment
Abutments prior
to preparation.
Preparation of the abutments with
specific drills depending on the
system following endodontic
treatment.
Post space
created in
abutments. Female component is
luted in post space
When resin sets, the
male component
will get attached to
denture. Denture with
attached male
component is then
removed from the
mouth.
Denture with filled resin
is placed over the
positioned male
component.
Autopolymerizing
denture base acrylic is
mixed and the created
space is filled with
resin.
Space created in denture
for
attachment of male
component.
Male component is
positioned on female
component prior to
attaching it to denture.

• RESILIENT STUDS :
• Resilient attachment systems are selected to perform a compensatory
service and to act as a safety valve for any overload situation.
• No two resilient attachment systems should oppose each other unless the
attachments in the maxillary prosthesis are locked out of function, for the
maxillary prosthesis receives additional support from the palatal coverage.
• This situation arises when two hybrid prostheses oppose each other or a
mandibular appliance opposes the maxillary denture.
107
ATTACHMENTS

• When the mandibular appliance opposes a natural dentition, some
provision should be made for movement so that maximal tissue contact of
the denture base can be achieved under maximal load.
• In the well developed denture base with careful positioning of the
attachments, the need for a resilient system becomes questionable.
• The retained root with an attachment offers retention and positional
or directional orientation for the appliance.
108
ATTACHMENTS

• No attempt should be made at equilibrating or establishing permanent
records or relining procedures without locking the resilient attachments out
of function, because the base would move and produce incorrect markings
of the interferences.
• When there is either inadequate technique or inability to develop a well
fitting denture base, the resilient attachment gives some leeway to
acceptance of the prosthesis by allowing more base contact and support
during function.
109
ATTACHMENTS

• A resilient attachment permits the tissue to compress slightly before any load is
transmitted to the abutment. It is usually preferred:
 When there are only a few abutments.
 When abutments have minimal bone support.
 For tissue tooth supported prosthesis.
 When functioning opposite natural dentition.
 When functioning against a nonresilient appliance (do not use opposite
another resilient appliance).
 When multi-directional (stress-broken) action is desirable.
 When there is a minimum denture base.
110
ATTACHMENTS

• NONRESILIENT STUDS :
• The nonresilient stud attachments are used when interocclusal space is
limited.
• They should be used when the teeth are stable or when the dentist does not
desire movement or potential movement of the overdenture.
111
ATTACHMENTS

• A non resilient attachment will not allow vertical movement (however it may
permit rotational movement)
 When no vertical movement is indicated.
 When an all-tooth supported prosthesis is desired.
 When a tooth-tissue supported appliance is desired.
 With strong abutments having maximum bone support (one-half or more).
 When functioning against a resilient prosthesis
 When a large, well-fitting denture base is possible.
 When there is little interocclusal space
 Opposite a complete denture.
112
ATTACHMENTS

• Some Stud Attachments:
1. Dalla Bona
2. Intrafix
3. Ancrofix
4. Gerber
5. Gmur
6. Rotherman
7. Huser
8. Schubiger
9. Ceka
113
ATTACHMENTS

• ANCROFIX :
• The Ancrofix* is a resilient pressure-button system that consists of four
parts:
• A solder base, a replaceable retention head, a housing with four lamellae to
activate, and a teflon ring to allow the lamellae to function.
• The overall height of the unit is 3.2 mm.
114
ATTACHMENTS

• The advantages of the Ancrofix are:
1. Tinfoil spacers can provide tissue resilience during fabrication.
2. The attachment allows rotational movement, and flattening the knob on
top of the male post deactivates it.
3. The components are replaceable, and it is easy to adjust the retention,
thereby giving the attachment an indefinite life.
115
ATTACHMENTS

4. The solder base is interchangeable with the Introfix attachment, allowing
exchange of attachments.
5. The button can be picked up in the mouth with resin or processed in the
laboratory.
6. There is no clinically significant torque to the support tooth when the
denture base is developed properly.
7. The attachment system is simple and inexpensive.
116
ATTACHMENTS

The disadvantages of the Ancrofix system are:
1. Use of more than one attachment requires a paralleling mandrel for
attaining proper alignment.
2. Improper base development and overtightening of attachments can
torque the teeth.
3. Repositioning the attachment during rebasing can damage the teflon ring.
4. This attachment is ideal for removable partial dentures and overdenture
fixation
117
ATTACHMENTS

• CEKAATTACHMENT
• This consists of a male portion affixed to the tooth and has a rounded shape
wider at the top and split vertically into four sections.
• These four sections are flexible and capable of being compressed.
• Over this fits a female housing or ring.
• The attachment also can be constructed with a different type of retaining
male that has a space between it and the female, allowing vertical play and
some rotational movement of the base.
118
ATTACHMENTS

THE GERBER ATTACHMENT
• The Gerber stud system is a versatile stud attachment used routinely.
• It consists of a male post soldered to the coping and a retentive female
secured within the denture base of the overlay prostheses.
• The Gerber attachment is furnished in two different types - a resilient and
non-resilient form.
119
ATTACHMENTS
Resilient Gerber Non resilient Gerber

120
The male post consists of two
parts - a threaded base, which is
soldered to the diaphragm of a
coping, and a removable sleeve
with a retentive undercut
The resilient female consists of a
housing, coiled spring, C-spring, a
retention sleeve and lock screw.
The non-resilient female has a
female housing, C spring and a
screw cap and no copper shim and
coil spring.
Convenient tools are also used
in the fabrication - female
screwdriver, male screwdriver,
paralleling mandrel, heating
bar, and a soldering cornal

• Advantages of the Gerber attachment
1. It provides adequate retention, stability and support.
2. Its retention is light and easily adjustable with springs adjustable and
readily replaced.
3. All of its post sleeves are interchangeable and replaceable, with the
exception of the male screw base.
4. It can be used in conjunction with bars.
5. It can be processed directly into the overdenture or positioned in the mouth
with autopolymerizing resin.
121
ATTACHMENTS

• Disadvantages of Gerber attachment
1. It is a complex attachment and maintenance problems are relatively
common. The male sleeve may become loose. The internal parts of the female
may dislodge when the retaining screw unthreads.
2. Its large vertical dimension makes it impractical for minimal interocclusal
space.
3. It requires an assortment of tools for fabrication and maintenance.
122
ATTACHMENTS

4. The attachments must be parallel.
5. The Gerber permits very little rotational action, so torquing of abutment
teeth will occur with alveolar resorption.
123
ATTACHMENTS

DALLA BONAATTACHMENT
• The Dalla Bona is a simple stud attachment making an excellent overdenture
attachment available in a resilient or nonresilient series.
• It is useful when there is minimal vertical space and where rotation,
resilience and retention are desired.
• It consists of a single piece male stud soldered to the coping and a single unit
female processed within the denture.
124
ATTACHMENTS

• It is available in two types:
1.Cylindrical
2.Spherical
• Dalla bona attachments on two cuspids makes it excellent overdenture
arrangement
• Male is a solid stud, female is a single component with retentive lamellae.
• A clear Teflon ring covers the female lamellae , Restored roots with copings
and spherical bonas
125
ATTACHMENTS

• Cylindrical Dalla Bona
• The cylindrical male post has parallel walls without an undercut.
• The female lamella fits snugly over the male posts, providing frictional
retention.
• A PVC ring fits around the female lamellae.
• This aids in fabrication, and permits the lamellae to flex.
• The cylindrical Dalla Bona must be parallel; therefore, the male posts must
be assembled using a paralleling mandrel and surveyor.
126
ATTACHMENTS

• Spherical Dalla Bona
• The spherical Dalla Bona is similar to the cylindrical, but the male post is
spherical.
• This sphere provides a retentive undercut which is engaged by the retentive
lamellae of the female.
• If a spacer is used during fabrication, this attachment will be resilient;
without the spacer, it will be nonresilient.
127
ATTACHMENTS

• Advantages
1. Their overall length varies between 3.3 millimeters (cylindrical), to 3.7
millimeters (spherical), so it is suitable for short interocclusal spaces.
2. It provides firm, definite retention.
3. It can be processed into the overdenture in the laboratory or mounted in the
mouth using autopolymerizing resin.
4. It is less expensive than the Gerber.
5. Parallelism of the spherical Bona is less critical than that of the cylindrical
Bona. DEPARTMENT OF PROSTHODONTICS, CROWN &
128
ATTACHMENTS

• Disadvantages
1. The retentive action of the female is very stiff and difficult to adjust.
2. The collar that retains the female housing in the prosthesis is too small.
Therefore the female may become loose with normal adjustments and use.
3. The males must be parallel, particularly in the cylindrical form.
4. There may be some torquing and tipping of the abutment.
129
ATTACHMENTS

THE ROTHERMAN ATTACHMENT
• The Rotherman is another excellent stud attachment.
• The Rotherman consists of a solid stud (that is soldered to the coping) and a
clasp like female (that is mounted in the overdenture.)
• Like many stud attachments, it is available in both resilient and nonresilient
designs.
• The resilient form has a taller male and is supplied with special spacers.
130
ATTACHMENTS

• The Rotherman is particularly applicable where interocclusal space is
limited, as the nonresilient design has a vertical dimension of just 1.1
millimeter and the resilient just 1.7 millimeter.
• The Rotherman anchorage has a short solid stud (non resilient right,
resilient left) and a double armed clasp.
• The clasp has bar for retention within the denture base
• Non resilient left and resilient right with aluminum spacer.
131
ATTACHMENTS

• The male features a definite undercut on just one side of the cylinder.
• A scribe line on the occlusal indicates the position of maximum undercut.
• The male must be soldered to the coping so that this line (and the undercut
below it) is positioned facially.
• This way, the female's clasp arms will reach around from lingual to engage
the undercut and the bar like retentive lug will fall in the lingual portion of
the denture
132
ATTACHMENTS

• There it will not interfere with the tooth setup and will be locked in thicker
resin.
• The Rotherman is the easiest of all attachments to solder, for it comes with
solder built into the center of the male.
• The technician need only position the male on the coping and then hold it in
a flame until the solder flows.
133
ATTACHMENTS

BAR ATTACHMENTS
• As the name suggests, bar attachments consist of a metal bar that splints two
or more abutments and a companion mechanism processed within the tissue
area of the overdenture.
• This mechanism snaps on the bar to retain the prosthesis.
• Bar attachments are available commercially in a wide variety of forms or
they can easily be "custom" fabricated.
134
ATTACHMENTS

• Sleeves/clips placed in the denture attach to the bar when denture is inserted,
providing retention
• Requires vertical and buccolingual space.
• Meticulous oral hygiene maintenance is essential.
135
ATTACHMENTS

• Classification Depending on number :
• Single bar
• Multiple bars
136
ATTACHMENTS

• Types of Bar Attachments
• Bar units
• Bar joints
137
ATTACHMENTS

• The Bar Unit
• This bar has parallel walls providing rigid fixation with frictional retention.
• It can be used for retention with long, medium or short copings, but only
when the appliance is to be an all tooth supported appliance (i.e. where no
stressbroken or rotational action is indicated).
• It is never used when a bar joint is indicated (when rotational or vertical
action is necessary); however, a bar joint can be used whenever a bar unit is
indicated.
138
ATTACHMENTS

• The Bar Joint
• The action of this attachment provides rotational or vertical movement. In
other words, it is a stress broken attachment.
• It has a rounded or semi rounded contour so the retention clip and
prosthesis can rotate slightly during mastication.
139
ATTACHMENTS

• THE DOLDER BAR
• An ideal bar attachment is the Dolder bar.
• It is well designed for splinting two or more abutments to provide support,
stability and retention for the overdenture.
• This bar attachment is manufactured in two forms a bar joint and a bar
unit.
• It is also available in two different diameters and lengths.
140
ATTACHMENTS

• The bar is straight with parallel sides and a round top. The sleeve or clip
that fits over the bar gains retention by friction only. The bar may be of
variable size and is pear-shaped at cross-section, similar to its
accompanying sleeve. This clip allows for some measure of rotational
movement about the bar (GPT8)
141
ATTACHMENTS

• Named after Eugene J. Dolder, a prosthodontist from Switzerland.
• It is available in diameters of 1.6 mm and 2.2 mm.
• Available as gold or titanium bars and sleeves.
• If more resiliency or movement is desired, a spacer is used between the bar
and sleeve while attaching the sleeve to the denture.
• This is removed and the space provided allows more movement of the
sleeve and denture.
142
ATTACHMENTS

• DOLDER BAR JOINT
• The pear shaped bar joint is designed to provide vertical and rotational
action so it is indicated where a stress-broken, resilient attachment is
desired.
• It can also be used as a bar unit for an all tooth supported prosthesis by
fabricating the overdenture without planned vertical movement.
143
ATTACHMENTS

• DOLDER BAR UNIT
• The bar unit is in the form of an inverted U with parallel walls.
• It does not permit rotational or vertical movement; therefore it only
provides retention and support, but maximizes the masticatory load on the
abutments.
144
ATTACHMENTS

• The Dolder bar unit is an excellent attachment when an all tooth supported,
non rotational acting overdenture is desired.
• This bar design may be indicated if there are numerous abutments -
especially if they are located in three planes; i.e. posterior and anterior
abutments.
145
ATTACHMENTS

• ACKERMANN AND CM BAR
• These bars are round at cross-section and hence are resilient
• Sleeves or clips are made up of gold.
• Available in 1.8 mm diameter, in plastic and gold.
• Spacer can be used if more movement is required.
146
ATTACHMENTS

• THE HADER BAR SYSTEM
• The Hader system is an excellent bar attachment.
• Similar to the customized bar, the Hader system consists of a plastic bar
pattern with gingival extension and small plastic clips that are processed
into the overdenture.
• This system has some advantages over others; the plastic bar pattern's
gingival extension can be trimmed to conform to the ridge.
• In addition, worn clips can be easily replaced at chair side using a special
seating tool.
147
ATTACHMENTS

• A rigid bar connecting two or more abutments, which when viewed in
cross-section, resembles a keyhole, consisting of a rectangular bar with a
rounded superior (occlusal) ridge that creates a retentive undercut for the
female clip within the removable prosthesis (GPT8)
• Named after the Swiss tool and die technician, Helmut Hader.
148
ATTACHMENTS

• Components of the Hader system are (from left to right).
• Plastic bar pattern (1.8 mm diameter, vertical height 5.7 mm).
• Plastic clips (5 mm long, 3 mm thick, 4 mm high).
• Modeling riders used in processing to create a slot for the clips.
• Clip seating tool.
149
ATTACHMENTS

• Advantages of the Hader System
1. The plastic bar pattern is easily adapted to differences in the surface of the
gingival ridge and gingival curvature.
2. The plastic bar pattern simplifies the laboratory technique by eliminating a
soldering step.
3. Plastic riders give adequate retention and are easily replaced.
4. Its rotational joint action relieves stresses from the abutment teeth.
150
ATTACHMENTS

• The main disadvantage of this system is its plastic rider which cannot be
altered for additional retention.
• However, the adjustable metal riders can be used to eliminate this problem.
• In addition, there is no provision for developing vertical function with the
overdenture.
• Commercial retentive clips can be used with these customized bars.
151
ATTACHMENTS

• MAGNETIC ATTACHMENT
• Magnetic attachments consist of
○ Keeper
○ Denture retention element
152
ATTACHMENTS

• The keeper is made of stainless steel and is cemented to the abutment tooth
153
ATTACHMENTS

• The denture retention element contains paired, cylindrical magnets made of
cobalt–samarium with opposite poles placed adjacent.
• One end is covered with a knurled housing which fits into the denture and
either end is smooth and fits on the keeper
154
ATTACHMENTS

• Advantages
• No path of insertion.
• No specialized instrumentation.
• No paralleling of abutment.
• Automatic reseating.
• Ease of repair and reline.
• Freedom in lateral and rotational movements.
• Minimum forces transmitted to roots.
155
ATTACHMENTS

• Disadvantages
• Smaller the root surface – decrease in retention.
• Alloy can corrode and fracture.
• Loss of magnetism is common with ensuing loss of retention – the
elements need constant replacement.
156
ATTACHMENTS

• BAR COMPARED TO STUD FIXATION
• The splinting of two or more teeth with a bar produces stability similar to
that obtained with rigid stud-type attachment when the overdenture is in
place.
• The question that arises immediately is that, if the denture base is so well
developed that the bar serves only as a fixation device, what is the end
difference in splinting between the stud prosthesis and the bar prosthesis?
Theoretically
157
ATTACHMENTS

• there is no difference, but the stud type allows independent movement.
• If one tooth is especially weak the strong tooth can serve as the fulcrum
point for movement of the weaker tooth in the prosthesis.
• When using bar units and joints the bar often splints in more than one plane.
158
ATTACHMENTS

• Instead of the prosthesis moving one tooth, all or none move under a
functional load with bar fixation.
• A stronger and a weaker tooth can be splinted with the result that the
stronger tooth strengthens the weaker tooth, and the weaker tooth weakens
the stronger tooth.
159
ATTACHMENTS

• AUXILLARYATTACHMENTS
• In addition to bars and studs, other attachment systems are applicable for
overdenture prostheses.
• These auxiliary attachments may be in the form of screws or spring loaded
plunger attachments.
160
ATTACHMENTS

• SCREWS:
• Schubiger Screw Attachment
• An excellent screw attachment often used in overdenture technique is the
Schubiger.
• This attachment is a very versatile screw-type system, used with Gerber and
bar combinations.
161
ATTACHMENTS

• Plunger-Type Attachments
• Auxiliary retention for an overlay prosthesis is often desirable and it may be
added to various coping or bar systems.
• Plunger type units such as the Ipsoclip, Presso-matic and IC attachments
can add additional retention
162
ATTACHMENTS

IMPRESSION
PROCEDURE
163

• CONSTRUCTION OF COPINGS
• An impression of the prepared tooth is obtained with reversible
hydrocolloid, and dies are poured in a minimal-expansion, vacuum-
spatulated artificial stone.
• Wax patterns for the copings are carved, sprued, invested, and casted.
164
IMPRESSIONS

• Polished copings are fitted to the abutment teeth with disclosing wax. If the
teeth have been treated endodontically, zinc oxyphosphate cement is used to
attach the copings.
• When the abutment teeth are vital, a hard-setting zinc oxide and eugenol
cement is used.
165
IMPRESSIONS

• MAKING THE FINAL IMPRESSION
• An accurate border-molded impression is made of the residual ridges and
the restored teeth with rubber-base impression material in an acrylic resin
tray.
• This impression will be used to make the master cast.
166
IMPRESSIONS

POST INSERTION
167

• In most instances, the patient is instructed to take the dentures out at night
and place them in a soaking-type denture cleanser
• The dentures should be brushed after each meal with a soft toothbrush and
hand soap.
• Maintenance of the supporting tissues may be facilitated by massage.
• One excellent method that patients generally like involves the chewing of
bubble gum for fifteen minutes twice a day.
168
POST-INSERTION

• Usually four to six cakes are chewed at one time with the dentures out of
the mouth.
• Sugar intake can be restricted by chewing sugarless gum.
• The patient is given thorough instructions on maintenance procedures for
the abutment teeth.
• Disclosing tablets are used to indicate the areas in need of special attention.
• The portion of the tooth adjacent to the gingival margin is critical and
requires meticulous cleaning.
169
POST-INSERTION

• Gauze strips approximately 12 inches long and l/z inch wide can be used in
a shoe-shining type motion to keep the abutment teeth clean and polished.
• Home care by the patient is a significant factor in obtaining a reasonable
service life for the restoration.
• Periodic recall is helpful to perpetuate preventive maintenance and to
evaluate the status of the home care.
170
POST-INSERTION

SUMMARY
171

• The discussion of overdentures has been confined to their capacity to use
abutment teeth to improve neuromuscular control of mandibular movement.
• Use of overdentures has been favored often because of their mechanical
advantages, but seldom because of the sensory role of the retained abutment
teeth.
• To date, most failures have been the result of poor case selection and
inadequate supervision to control maintenance.
172
SUMMARY

• Emphasis must be placed on proper patient selection, patient motivation,
basic prosthodontic principles, and a detailed program of homecare
instruction and frequent recall
• Furthermore, the recent introduction of the osseointegration technique
created the possibility of converting patients with maladaptive complete
dentures into ones with adaptive overdentures when implants are used to
stabilize “offending” prostheses
173
SUMMARY

• As a result, the twin techniques (traditional complete denture fabrication
with natural teeth abutments or with implants) now offer dentists and
patients a new standard of prosthodontic therapy
174
SUMMARY

REVIEW OF LITERATURE
175

• Joseph T. Quinlivan (1974) said that retention is a problem for overlay
dentures over simple copings when only two teeth remain. This is
particularly a problem when treating a mandibular arch, which has a
more limited basal seat area. He advocated RCT of the abutment teeth;
pulp space to be enlarged with a Gates Glidden drill and finally with a
safe sided para post drill. Then he advocated used ball and socket type
of attachment for overdenture on the teeth reduced I mm above the
gingiva.
176
REVIEW

• Wayne R. frantz (1975) described the construction of tooth supported
dentures where the natural tooth was utilized and the acrylic resin for
denture base processed directly to the prepared cast. He said that
abutment teeth with their coping may result in 3-5 mm above the
gingiva which causes undue stress and torque on the teeth. He
advocated natural teeth to be reduced 1-2 mm above gingiva fill the
pulp chamber with amalgam and give a very high polish and construct
the denture.
177
REVIEW

• A. B. Warren and A. A. caputo (1975) conducted a study to determine
and compare the transfer of forces to the alveolar bone for five
different abutment designs for the tooth supported dentures and
concluded that there was a direct relationship between the stability and
retention that each design provided and the amount of stress and
torque transferred to the supporting structures. Attachments that used
parallelism or undercuts for retention tend to produce the most severe
stress conditions in the supporting alveolus.
178
REVIEW

REFERENCES
179

• Heartwell CM. Syllabus of complete denture.
• Mensor Jr MC. Attachment fixation of the overdenture: Part II. The Journal of prosthetic dentistry.
1978 Jan 1;39(1):16-20.
• Zarb GA, Jacob R, Eckert S. Prosthodontic treatment for edentulous patients, 13/e. Elsevier India;
2012.
• Lord JL, Teel S. The overdenture: patient selection, use of copings, and follow-up evaluation. The
Journal of prosthetic dentistry. 1974 Jul 1;32(1):41-51.
• Preiskel HW. Overdentures Made Easy: A Guide to Implant And root Suppurted Prostheses.
• Winkler S, editor. Essentials of complete denture prosthodontics. Year Book Medical Pub; 1988.
180
REFERENCES

• Robbins JW. Periodontal considerations in the overdenture patient. Journal of Prosthetic Dentistry.
1981 Dec 1;46(6):596-601.
• Thayer HH, Caputo AA. Effects of overdentures upon remaining oral structures. The Journal of
prosthetic dentistry. 1977 Apr 1;37(4):374-81.
• Kay WD, Abes MS. Sensory perception in overdenture patients. The Journal of prosthetic
dentistry. 1976 Jun 1;35(6):615-9.
• Quinlivan JT. An attachment for overlay dentures. The Journal of prosthetic dentistry. 1974 Sep
1;32(3):256-61.
• Morrow RM, Feldmann EE, Rudd KD, Trovillion HM. Tooth-supported complete dentures: an
approach to preventive prosthodontics. The Journal of prosthetic dentistry. 1969 May 1;21(5):513-
22.
181
REFERENCES

tooth supported Overdentures

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to tooth supported Overdentures

Similar to tooth supported Overdentures (20)

Recently uploaded

Recently uploaded (20)

tooth supported Overdentures

Editor's Notes