• It requires mandrel for alignment with additional attachments.
• It is processed in a laboratory.
• Torque potential is maximum, if the denture base is not adapted
• A magnet consists of detachable keeper elements made of stainless
steel; it is fixed to the abutment tooth.
• Denture retention elements have paired cylindrical, cobalt–
samarium magnets, axially magnetized and arranged with their
• Flat magnet faces are covered by magnet keeper and on the other end
by thin stainless steel plates.
• These plates protect the magnets against wear and corrosion and
Bar attachments are one of the most widely used attachment, if
adequate vertical space is available. These provide rigid splinting of the
abutment teeth, enhance retention, stability and support and can be
used with all coping sizes. Bar attachments are of two types:
(a) Bar units: These act as a fixed unit. These provide rigid fixation
with frictional retention. It is indicated in totally tooth-supported design.
(b) Bar joints: These have a curved contour and allow the prosthesis to
rotate around the bar slightly. These permit rotational movement
between the bar and the sleeve and allow some of the load to be borne
Some of the commonly used bar attachments are as follows:
• It can be used as bar unit or as bar joint and as stud
• It consists of prefabricated plastic bars and clips
• The plastic bars are attached to the coping wax-up
and is casted along with the coping.
• The plastic clips are embedded in the denture to aid
in retention or can be casted in metal.
• If additional retention is required, more clips may
be added on a bar and tension on the metal clip
• Preformed plastic bars allow fabrication in any
• Retention can be controlled.
• It has capability to follow anteroposterior gingival
• Assembly technique is simple.
• Bar and clip assembly is bulky.
• Retention may be lost rapidly due to wear of plastic
• It can be used as bar unit and bar joint.
Bar unit consists of preformed bar which is soldered
to the coping on the abutment tooth:
• Shape of the bar has parallel sides with a rounded top.
• Sleeve which is embedded with the resin in the
denture rests over the bar to provide retention with
• Movement is negligible and assembly is rigid.
• Bar unit is bulky and it is difficult to achieve
FIGURE 13-8 Egg-shaped Dolder bar joint.
Dolder bar joint is an egg-shaped bar with a brass spacer to provide
• The spacer allows the sleeve to have a vertical and rotational
• Assembly is bulky, which hinders in achieving good aesthetics.
• It is expensive and requires exceptional skill for its use.
• It is available in 11 and 14 gauges.
• It is adjustable for retention and provides rotational
• Retention for the clip is not provided.
• It provides joint movement only.
• It consists of a series of curved austenitic friction bars
of different radii with corresponding retentive
• It requires complicated mechanical joining and
soldering of a nonprecious metal bar to a coping.
• Both the bar joint attachments are similar in design.
• These consist of the round bar soldered to the post
copings and a clip that fits over the bar.
• These supply a spacer to aid in vertical and
• These are small in size and can be easily fixed.
• These provide excellent retention.
Success or failure of the overdenture treatment depends entirely on its
maintenance. There are certain problems associated with the
• Recurrence of periodontal disease
• Loss or breakage of attachment components
• Breakage of overdenture prosthesis
• Poor retention and stability
Most of the problems can be prevented by proper diagnosis and
treatment planning. During planning on the type of attachment, the
patient’s manual dexterity should be considered. Properly planned
and fabricated overdenture will last for a longer period of time than
• The patient is educated and trained on path of placement and removal
• The patient is instructed not to bite the prosthesis into position but
• Initially patient may complain of bulky prosthesis and problem in
• The patient is instructed to read aloud until he/she becomes
accustomed to the bulk of the prosthesis.
• The patient is instructed to take small bites, chew slowly and chew on
both the sides of his/her mouth.
• Proper home care instructions are given to the patient.
• The patient is taught proper technique for brushing and cleaning the
• Oral hygiene maintenance aids are suggested to the patient such as
dentrifice, toothbrush, floss, toothpick, stimulating devices,
disclosing solution and water irrigation devices.
• Soft, multitufted nylon brush with bristles are recommended. The brush
is held at 45° angulation to the gingiva, coping and bar. The brush is
moved in short circular motion.
• Unwaxed dental floss is recommended.
• The dental floss should be wrapped around the abutment and is
moved up and down to remove the plaque. Care should be taken
• Interproximal brush can be prescribed in cases of more open
interproximal areas. It is gently moved back and forth from the
facial and then to the lingual direction.
• Overdenture primarily preserves bone, preserves proprioception
and enhances patient’s manipulative skills.
• Application of low concentration stannous fluoride or 0.5% APF gel
is recommended on abutment teeth to reduce caries rate.
• Overdenture treatment is highly useful in the patients with
congenital anomalies such as cleft palate, microdontia,
amelogenesis imperfecta and dentinogenesis imperfecta.
• In immediate overdenture concept, certain poorly prognosed teeth
are removed and denture is inserted over the remaining teeth until
complete healing of the extraction site occurs.
• Immediate overdenture concept was popularized by J.L. Lord and S.
14. Introduction to removable partial dentures
15. Diagnosis and treatment planning
16. Components of removable partial denture
19. Impression making in removable partial denture
20. Laboratory procedures, occlusal relationship
and postinsertion of removable partial denture
21. Insertion, relining and rebasing
Introduction to removable partial
On the Basis of Type of Attachment of the
Denture to the Natural Teeth, 225
On the Basis of Type of Support, 225
On the Basis of Type of Material, 225
Indications and Contraindications of RPD, 225
Classification of Partially Edentulous Arches, 226
Kennedy’s Classification and Applegate’s
Commonly Used Classification for Partially
Sequential Phases in Treating a Partially
Edentulous Patient with Removable
Replacement of teeth in partially edentulous individuals using
removable partial dentures (RPDs) demands preserving health of
remaining hard and soft tissues, restoration of oral comfort, function,
Removable prosthodontics is defined as ‘the branch of prosthodontics
concerned with the replacement of teeth and contiguous structures for
edentulous or partially edentulous patients by artificial substitutes that are
readily removable from the mouth’. (GPT 8th Ed)
Removable prosthodontics can be broadly classified as follows:
(i) Removable complete prosthodontics: This refers to the replacement of
teeth and adjacent structures in completely edentulous patients
(ii) Removable partial prosthodontics: This refers to the replacement of
teeth and adjacent structures in partially edentulous patients with
partial dentures. It is of two types: extracoronal and intracoronal.
On the basis of type of attachment of the denture
On this basis, it can be classified as:
Extracoronal retainers: This is defined as ‘that part of a fixed dental
prosthesis uniting the abutment to the other elements of the prosthesis that
surrounds all or part of the prepared crown’. (GPT 8th Ed)
The commonly used extracoronal retainers are in the form of clasps.
The clasp assembly consists of the retentive arm which is located in
the undercut area of the tooth and the reciprocal or bracing or
stabilizing arm which lies above the undercut area on the opposite
Intracoronal retainers: These retainers are located within the tooth and
the retention of the denture depends on the exact parallelism of the
two retentive units. Intracoronal attachments are used in this type
Intracoronal attachment is defined as ‘any
prefabricated attachment for support and retention of a
removable dental prosthesis. The male and female
components are positioned within the normal contours of
the abutment tooth’. (GPT 8th Ed)
On the basis of type of support
On the basis of type of support, RPD is classified as follows:
(i) Tooth supported: When RPD derives its support from the abutment
(ii) Tooth and tissue supported: When RPD derives support from both
the abutment tooth and the edentulous ridge.
On the basis of type of material
On the basis of the type of material used, RPD is classified as follows:
(i) Complete acrylic: RPD is conventionally made up of acrylic (e.g.
cross-linked heat-cure acrylic resin).
(ii) Metal based: RPD framework is made of metal (e.g. type III or IV
gold alloys, base metal alloys and titanium alloys).
Indications and contraindications of
All forms of prosthodontic treatment should give due consideration to
DeVan’s dictum given by Muller DeVan (1952), which states that ‘the
preservation of that which remains and not the meticulous replacement of
• Maintaining or improving phonetics
• Establishing masticatory efficiency
• Maintaining the health of the masticatory system by preventing
undesirable tooth movement and by evenly distributing the occlusal
• Length of the edentulous span: Longer edentulous span should be
restored with RPDs, as it is stabilized and supported by the teeth
present on the opposite side of the arch and by the residual ridge.
This cross-arch stabilization considerably reduces the harmful
leverage and torquing forces onto the abutment tooth/teeth.
• Cross-arch stabilization: In cases where the remaining teeth are
periodontally compromised, bilateral cross-arch stabilization is
required to resist harmful torquing and lateral forces.
• Questionable periodontal status of the remaining teeth
• Excessively resorbed residual ridges
• Immediate replacement after extraction: Soon after extraction, it is
best to replace with a provisional RPD which can be relined over a
period of time as resorption occurs.
• Aesthetic reason: In cases of multiple missing anterior teeth, it is
better to replace with RPD to provide better aesthetics. The denture
teeth can provide life-like natural appearance in comparison to the
pontics of fixed denture which appears flat and dull. Moreover, the
denture base can be characterized for an individual patient to
• Patient’s preference: Sometimes patients prefer and insist on
removable prosthesis. This is due to the following reasons:
• The patients want to avoid preparation of the sound
• Patient’s physical or emotional condition: The patients with
physical or emotional problems find it difficult to undergo lengthy
procedures involved in fixed treatment and, therefore, prefer RPD
which can be completed in much shorter time.
• Age of the patient: Fixed prosthodontic treatment is avoided in a
young patient because of the large pulp horns and lack of clinical
crown height. In a very old patient, reduced life expectancy
contraindicates fixed treatment.
• Patient’s mental health: It is avoided in mentally retarded patient
• Poor oral hygiene: Success of any prosthodontic treatment will be
questionable in such patients.
• Large tongue: Displacement tendency of removable denture is high.
• Medical condition: RPD should be given with caution to patient
Classification of partially edentulous
There is a definite need to classify partially edentulous arches so as to
aid in proper diagnosis and treatment planning.
The classification should be used because of the following reasons:
• It helps in proper diagnosis and treatment planning.
• It helps to communicate with the technician or professional.
• It helps to anticipate complexity of the treatment.
• It helps to formulate the best treatment for the patient according to
the given individual condition.
Requirements for an acceptable classification are as follows:
• It should be universally acceptable.
• It should allow visualization of the type of partially edentulous
• It should permit differentiation between the tooth-supported or
• It should provide guidance on the type of design to be used.
Kennedy’s classification and Applegate’s
• This is the most commonly used classification.
• It was originally proposed by Dr Edward Kennedy in 1925.
• The original classification consists of four classes and applies to
most of the partially edentulous arches.
• It is simple, logical and the widely accepted classification.
• However, it cannot quantify the amount of support for the tooth-borne
• Edentulous areas, other than those determining the classification,
are described as modification spaces.
Kennedy’s classification has following four classes:
Class I: Bilateral edentulous areas located posterior to the remaining
Class II: Unilateral edentulous area located posterior to the
remaining natural teeth (Fig. 14-2)
Class III: Unilateral edentulous area with natural teeth located both
anterior and posterior to it (Fig. 14-3)
Class IV: Single, bilateral edentulous area located anterior to the
remaining natural teeth such that it crosses the midline (Fig. 14-4)
Any additional edentulous area is referred to as modification space.
FIGURE 14-3 Kennedy class III.
• Dr O.C. Applegate modified Kennedy’s classification by adding two
• However, acceptance of this modification has not been universal.
Class V: Edentulous area bounded by natural teeth both anterior and
posterior to it but the anterior abutment is not suitable for support
Class VI: Teeth adjacent to the edentulous space are capable of
providing complete support to the prosthesis
FIGURE 14-5 Kennedy Applegate’s class V.
Applegate’s rules for applying Kennedy’s classification
Rule 1: Classification should follow rather than precede the extraction of
teeth that might alter the original classification.
Rule 2: If the third molar is missing and is not to be replaced, it is not
considered in the classification.
Rule 3: If the third molar is present and is to be used as abutment, it is
considered in the classification.
Rule 4: If the second molar is missing and is not to be replaced because
of the missing opposing tooth, it is not considered in the
Rule 5: The most posterior edentulous area or areas always determine the
Rule 6: Edentulous areas, other than those determining the
classification, are referred to as modification spaces and are
Rule 7: Extent of modification is not considered, but only the number of
additional edentulous area is considered.
Rule 8: Class IV does not have any modification areas.
Commonly used classification for partially
Apart from the Kennedy’s classification, some of the most commonly
used classifications are given below.
• This classification was proposed in 1920 and is the first to be
• This is a classification based on the position of the direct retainers.
Class I: Diagonal, two direct retainers are diagonally opposite to each
Class III: Unilateral, two direct retainers are present on the same side
Class IV: Bilateral, three direct retainers in triangular configuration or
four direct retainers in quadrilateral configuration (Fig. 14-7)
FIGURE 14-6 Cummer’s class I: two direct retainers
FIGURE 14-7 Cummer’s class IV: three direct retainers
M. Bailyn’s classification (1928)
This classification is based on the type of support. Bailyn called the
Anterior restorations had saddle areas anterior to the first premolar
and posterior restorations had saddle area posterior to the canine.
Class I: Bounded saddle (less than three teeth missing)
Class II: Free-end saddle (edentulous posterior spaces)
Class III: Bounded saddle (more than three teeth missing)
F. Neurohr’s classification (1939)
It is a complex classification which is not currently used.
E. Mauk’s classification (1942)
This classification is based on the following characteristics:
• Number, length and location of the edentulous spaces
• Number and position of the remaining teeth
Class I: Bilateral posterior edentulous spaces
Class II: Bilateral edentulous spaces with teeth/tooth present
posterior to one of the spaces
Class III: Bilateral edentulous spaces with teeth/tooth present
Class IV: Unilateral edentulous space without any tooth posterior to
Class V: Anterior edentulous space with unbroken posterior arches
Class VI: Irregular edentulous spaces in the arch
R.J. Godfrey’s classification (1951)
This classification is based on the location and extent of the edentulous
Class I: Tooth-supported denture base in the anterior part of the
mouth (e.g. broken five-tooth space or unbroken four-tooth space)
Class II: Tissue-supported denture base in the anterior region (e.g.
Class III: Tooth-supported denture base in the posterior region (e.g.
Class IV: Tissue-supported denture base in the posterior region (e.g.
J. Friedman’s classification (1953)
This classification is based on the boundaries of the spaces.
C: Cantilever or posterior free end
L.S. Beckett’s and J.H. Wilson’s classification
This classification is based on Bailyn’s classification and considers the
amount of support provided by the teeth and the tissue.
Class II: Tooth- and tissue-borne saddle and totally tissue-borne
Class III: Inadequate tooth support and inadequate tissue support for
F.W. Craddock’s classification (1954)
Class I: Saddles supported on both the sides with adequate number
Class III: Tooth supported only at one end of the saddle
Sequential phases in treating a partially
edentulous patient with removable prosthesis
When treating a partially edentulous patient with a removable
prosthesis, the treatment should be carried out sequentially in five
Phase 1 (educating the patient): The patient should be educated about
the benefits and limitations of the treatment with removable
prosthesis. Patient education is essential and should start at the first
contact and should continue throughout the treatment. It is
important to educate the patient about the maintenance of oral
hygiene and care of the prosthesis.
Phase 2 (diagnosis, treatment planning, design considerations and
mouth preparation): With the help of medical and dental history of
the patient, complete oral examination including clinical and
radiographic evaluation is done. Mounted cast is helpful in
diagnosis and treatment planning. Surveying of the diagnostic cast
is absolutely essential in treatment planning. Once the type of the
prosthesis is planned, mouth preparation is performed.
Phase 3 (obtaining support for distal extension cases): The soft tissue
is recorded in functional form. To obtain adequate support,
corrected impression techniques and fabrication of the altered cast
Phase 4 (establishments and verification of the occlusal relations
and teeth arrangement): Jaw relation is recorded after successfully
verifying the fit of the cast partial framework in the mouth. Proper
occlusal relationship and teeth arrangements are important steps in
construction of the partial dentures.
Phase 5 (initial placement procedures): Occlusal harmony is ensured,
minor processing errors are corrected. Functional reline of the
denture base is done in cases of distal extension bases. Postinsertion
instructions are given to the patients.
• Maxillary first molar is the most commonly missing tooth in
• The primary objective of the partial dentures is to preserve those
tissues that remain in a state of health.
• Removable partial denture is best suited for patient with high caries
index and having poor oral hygiene.
• Displaceability of mucoperiosteum is 2.0 mm and that of
periodontal ligament is 0.25 ± 0.1 mm.
Objectives of Prosthodontic Treatment for a Partially Edentulous
Importance of Medical Condition of Patient before Oral
Diagnostic Cast and Its Importance, 233
Mounted Diagnostic Casts as Fundamental
Diagnostic Aids in Dentistry, 234
Importance of Radiographs in Removable Prosthodontics, 235
Radiographic Evaluation of the Abutment
Periodontal Evaluation of Partially Edentulous
Splinting and Its Role in Prosthodontics, 237
Disadvantages of Splinting, 238
Removable Permanent Splints, 239
Thorough diagnosis and sequential treatment plan are essential for
successful removable partial denture treatment. Diagnostic
information is obtained after considering patient information, clinical
examination, radiographic analysis, diagnostic models and
preliminary survey of the casts. On the basis of these key elements of
diagnosis, partial denture design is established and treatment
Clinical diagnostic procedure for partially edentulous patient is
similar to that of completely edentulous patients, which is already
discussed in Chapter 2. In this chapter, we have focussed on
additional diagnostic and treatment options and their importance.
Objectives of prosthodontic treatment
for a partially edentulous patient
The objectives of prosthodontic treatment for a partially edentulous
• To preserve the remaining teeth and oral tissues in a healthy state
• To improve or establish the masticatory efficiency
• To develop and restore aesthetics
• To maintain or improve the phonetics
Importance of medical condition of
patient before oral examination
It is very important to assess the general health of the patient before
performing the oral examinations. The patient should be asked to
complete the health questionnaire. Any positive response should be
thoroughly investigated during the interaction with the patient. Vital
stats, such as the measurement of blood pressure, pulse and
respiratory rate should be examined. The symptoms, manifestations
and prognosis of the disease should be evaluated. It is important to
determine the effect such diseases will have on the prosthodontic
treatment. If in doubt, the patient’s physician should be consulted.
Some of the systemic conditions that may have significant effects on
the prosthodontic treatment are:
1. Diabetes: Those who are suffering from uncontrolled diabetes may
have high sugar levels with multiple oral abscesses and poor tissue
• The patients are more prone to infection.
• The patients have reduced salivary flow which may
reduce their ability to tolerate the removable
Caution: Uncontrolled diabetes should be brought
under control before prosthodontic treatment.
2. Arthritis: Patients with arthritis may show changes in the
temporomandibular joint (TMJ). In these cases, it would be difficult to
3. Parkinson disease: The disease is characterized by rhythmic
contractions of the musculature, including muscles of mastication. In
• The patient has excess salivation and poor dexterity.
• It is difficult to make impressions and record jaw
4. Pemphigus vulgaris: This disease is characterized by the formation
of bullae in the oral cavity. The disease results in dryness of the mouth
and painful ulcers in the oral cavity. As a result, it is difficult for the
patient to tolerate the prosthesis.
Treatment: The disorder can be controlled with
medication and the prosthesis should be highly
polished with smooth contours of partial denture.
5. Epilepsy: In case of epilepsy, fabrication of partial dentures is
contraindicated, if the patient reveals a history of frequent seizures.
• If epilepsy is controlled, then prosthesis can be
• The prosthesis should be made of radio-opaque
• Medical consultation is a must before starting
6. Cardiovascular disease: Medical consultation is a must and a
written approval should be obtained.
• Prophylactic antibiotics are recommended before
• If such patients are not handled with caution, there
Diagnostic cast and its importance
Diagnostic cast is defined as ‘a life size reproduction of a part or parts of
the oral cavity and/or facial structures for the purpose of study and treatment
A diagnostic cast is an accurate reproduction of teeth and adjacent
structures, which aids in proper diagnosis. It is made up of dental
stone and usually an alginate impression is made to record the details
in the oral cavity. It plays an important role in proper diagnosis and
treatment planning of partially edentulous patient.
Importance of Diagnostic Cast (Figs 15-1 and
• It permits analysis of soft tissue and hard tissue contours in the
• It permits visualization of the occlusal contact from both the buccal
• It helps to determine the type of restoration to be placed.
• It helps to identify and locate the deflective occlusal contact.
• It helps to determine the need for surgical correction of bony
exostosis, high frenal attachment, bulbous tuberosity and severe
• It can be surveyed and the proposed design of the prosthesis can be
• It is helpful in the patient education.
• Interarch space can be evaluated on the mounted casts on the
• It helps in visualization of the occlusal plane and tooth migration
that may require correction before fabrication of the prosthesis.
FIGURE 15-1 Section of maxillary diagnostic cast.
FIGURE 15-2 Section of mandibular diagnostic cast.
Mounted diagnostic casts as fundamental
Mounted diagnostic casts are indeed an important aid for proper
diagnosis and treatment planning of partially edentulous patients.
The casts accurately mounted on the articulator help in proper
visualization of the occlusion, location and position of the remaining teeth
FIGURE 15-3 Mounted diagnostic casts.
Objective of diagnostic mounting
The objective of diagnostic mounting is to position the cast on the
articulator in the same relationship as the mandible to maxilla in the
Importance of Diagnostic Mounting
• To analyse and visualize the occlusion of the patient from all
• To study the position, location of the teeth, interarch space and any
• To analyse the soft tissue and hard tissue undercut
• To help in educating the patient about the treatment plan
• To provide permanent record of the oral condition before treatment
Radiographic examination should always be used with the clinical
findings to determine the existence of pathology in the oral cavity
with special attention to the abutment tooth and the residual ridge. It
is one of the most important diagnostic tools.
Rationale of Radiographic Examinations
• To determine the presence and the extent of caries, and the relation of
carious lesions to the pulp and the periodontal ligament
• To evaluate the quality and quantity of the alveolar bone
• To locate the area of infection and other pathosis that may be present
• To evaluate the existing restorations for recurrent caries, marginal
leakage and overhanging restorations
• To evaluate the alveolar support of the abutment teeth, their number,
crown-to-root ratio and morphology of the roots
• To determine the presence of root fragments, bony spicules and irregular
• To evaluate the alveolar support of the prospective abutment
• To permit an evaluation of periodontal conditions and to establish
the need and possibility for treatment
Radiographic evaluation of the abutment tooth
• Multirooted teeth with long divergent roots are more favourable
abutment teeth than single-rooted teeth.
• Crown-to-root ratio can be determined with radiographs by using
long cone paralleling technique.
• Changes in the lamina dura reveal the prognosis of the abutment
• Absence of lamina dura indicates periodontitis.
• Thinning of the dural space indicates periodontal disease.
• Uninterrupted lamina dura indicates a good prognosis of the
• Thickening of the lamina dura indicates tooth mobility, occlusal
Bone index areas are those areas on the alveolar bone that are
subjected to greater force than normal.
• Positive bone factor: Alveolar bone which can favourably react to
additional stress. Responses in favour of the positive bone factor are
dense lamina dura, dense cortical bone, normal bone height, normal
periodontal ligament space and supportive trabecular pattern (Fig.
• Negative bone factor: This is characterized by bones that respond to
stress unfavourably, prone to resorb rapidly under occlusal force
and such abutment teeth provide poor bone support (Fig. 15-5).
FIGURE 15-4 Schematic diagram showing positive bone
FIGURE 15-5 Schematic diagram showing negative bone
Periodontal evaluation of partially edentulous
Most of the partially edentulous patients have evidence of gingivitis
and periodontal disease. Such periodontal disease needs treatment
before a prosthodontic restoration can be done. The health of the
periodontium of the remaining teeth should be thoroughly and
systematically evaluated. This can be done as follows:
• By observing the colour, texture and architecture of the gingiva
• The presence of periodontal pocket is detected by using a calibrated
• By observing the presence of cervicular exudates using digital
pressure or probing techniques
• By determining the width of the attached gingiva
• By observing any tension placed on the attached gingiva by the
• By complete radiographic examinations
Signs and symptoms of periodontal disease
• Periodontal pocket depth greater than 3 mm
• Change in colour and contour of gingiva
• Presence of cervical marginal exudates
• Tension of the attached gingiva by muscle or frenum
• Width of the attached gingiva less than 2 mm
Any sign of the presence of periodontal disease will require
treatment before prosthodontic intervention. If the abutment tooth is
periodontally weak, it should be critically evaluated. The causative
factors should be eliminated and the progression of the disease should
be reversed to consider a tooth a ‘prospective abutment’. Several
treatment options are available to restore the abutment tooth to
optimum health. Some of the available treatment options are:
• Root scaling and root planning
• Free gingival graft to provide adequate width to the attached
Splinting and its role in prosthodontics
Splinting is defined as ‘the joining of two or more teeth into a rigid unit by
means of fixed or removable restorations or device’. (GPT 8th Ed)
Splint is defined as ‘a rigid or flexible device that maintains in position a
displaced or movable part’. (GPT 8th Ed)
There are two types of splinting, namely, removable splinting and
• It is helpful in stabilizing the periodontally compromised teeth by
• Mobility of the teeth with removable splinting is either decreased or
• The philosophy behind removable splinting is broad stress
• It consists of rigid major and minor connectors with multiple clasps and
• Lateral movement of the weakened teeth is minimized by
• Periodontally compromised teeth are rigidly supported not only
during the functioning of prosthesis but also during the removal of
• Splinting using clasps is done when no other approach is feasible. It
is done by clasping one or more teeth in the arch by multiple rests
and guiding the planes for stabilization of the prosthesis and the
• The main advantage of removable splinting is to provide cross-arch
• Swing-lock partial dentures can be used effectively to splint remaining
• It is accomplished by giving full veneer crowns splinted together
• Pin-ledge restorations can also be used for splinting.
• Splinting of two or more teeth increases the periodontal ligament
area and thus helps to distribute the stresses over the wider surface
• Splinting using crowns helps in stabilizing the abutment teeth in the
anteroposterior direction and not in the buccolingual direction.
• For a splint to stabilize in the buccolingual direction, it should
extend around the curve of the arch.
• To resist the lateral forces, cross-arch stabilization is required, which
can be provided by a rigid major connector.
• In cases where there is loss of attachment due to periodontitis.
• In case of short or tapered single-rooted tooth which is a proposed
abutment tooth, splinting with the adjacent tooth can in effect
produce a multirooted abutment tooth.
• In cases of pier abutment, where usually the bicuspid is splinted to
the stronger anterior tooth such as canine by fixed partial denture.
Extremely weak abutment tooth should not be splinted with strong
tooth. This will actually weaken the stronger tooth.
According to Ross, A. Weisgold and A. Wright, splints are classified
on the basis of the duration of use.
• Removable extracoronal splints
• Etched metal resin-bonded splints
(ii) Provisional stabilization
• Metal band and acrylic splints
• Combination of removable and fixed splints
• These should be simple and cost-effective.
• These should be stable and efficient.
• These should be nonirritating and hygienic.
• These should not interfere with the treatment.
• These should be aesthetically acceptable.
• These should not require any excessive tooth cutting or preparation.
• These should not interfere with speech and function.
• To reduce mobility and distribution of forces to number of teeth
• To prevent tooth migration, food impaction and supraeruption
• To improve masticatory function and aesthetics
• To eliminate pain and discomfort
• To stabilize the proximal contact
• To provide a favourable environment for healing of the tissues
• Immobilization with splinting permits undisturbed healing.
• Functional forces are redistributed to number of teeth.
• Splinting redirects the forces more axially over all the teeth included
• It restores integrity of the arch by restoring the proximal contact of
• It restores the functional stability.
• It ensures psychological well-being.
• It is difficult to do any extensive restorative procedure.
• It is difficult to achieve marginal adaptation, good contour or
• To have a common path of insertion, additional tooth reduction may
• It poses difficulty in plaque removal.
Classification of Permanent Splints
According to D.A. Grant, J.B. Stern and M.A. Listgarten, permanent
splints are classified as follows:
Overdentures (full or partial)
Full coverage, three-fourths coverage crowns and
(iii) Cast metal resin-bonded fixed partial denture (Maryland splints)
Partial dentures and splinted abutments
Full or partial dentures on splinted roots
Fixed bridges incorporated in partial dentures seated
• Removable permanent devices incorporate continuous clasps and
fingers that brace loose teeth.
• These usually provide support from the lingual surface and may
incorporate additional support from the labial surface or using
• Palatal bars may be added to provide cross-arch splinting effect.
• Some may use pins that fit into the grooves or holes in inlays.
• Cosmetic disadvantages of labial continuous clasping can be
overcome by the use of swing-lock appliances which tend to hide
the metal of the splint and avoiding torque on the teeth.
• These are used in situations where the fixed splinting is not possible
• These are indicated when remaining teeth are too mobile to be used
as abutment or their position is not favourable for the conventional
• When there are few teeth with questionable prognosis, overdenture
• Few remaining teeth that may be periodontally weak can still be
used as abutment for overdenture, if they are strategically located in
• Retaining the teeth preserves bone and preserves proprioception.
• This also improves the function and the patient acceptability.
• Stability is the most important quality of the partial denture.
• Kennedy class IV has no modification spaces.
• Contingency design of partial denture refers to a transitional
denture. If a tooth with questionable prosthesis is removed, that
tooth is added in the existing denture.
Components of removable partial
Components of Removable Partial
Internal and External Finish Lines in Relation to Minor
Types of Rests Used in Partial Dentures, 253
Direct Retainers and Intracoronal Retainers, 254
Requirements of the Clasp Assembly, 255
Types of Circumferential Clasp, 257
Gingivally Approaching Clasp, 260
Indirect Retainers and Their Importance in Distal Extension
Indirect Retainers in Distal Extension
Factors Influencing the Effectiveness of the
Types of Indirect Retainers, 265
Denture Base and Functions of Distal Extension Partial Denture
Requirements of Ideal Denture Base, 266
Functions of Distal Extension Partial Denture
Anterior Teeth Replacement, 267
Posterior Teeth Replacement, 267
Components of removable partial denture
Removable partial dentures (RPDs) consist of the following parts:
Major connector is defined as ‘a part of removable partial denture which
connects the components on one side of the arch to the components on the
opposite side of the arch’. (GPT 8th Ed)
All the remaining components of the partial denture should join the
major connectors directly or indirectly. All major connectors should
fulfil certain requirements, which are described below.
Ideal requirements of major connectors
• Major connectors should be rigid, as it allows the functional stresses
to be effectively distributed over the supporting areas and the
• These should vertically support and protect the soft tissues.
• These should provide means for attaching indirect retainers whenever
• These should be comfortable to the patient.
• These should be easily cleanable and should not lodge food
Desirable features of major connectors
• Major connectors should never terminate on the highly vascular gingival
tissues, as they are susceptible to trauma from pressure.
• In the maxillary arch, the border of the major connectors should be
at least 6 mm from the gingival margin of the teeth.
• In the mandibular arch, the border of the major connectors should
be at least 3 mm from the gingival margin of the teeth.
• The border of the major connectors should be round and parallel to
• If the gingival margin needs to be crossed, it should cross at right
angle to produce least contact with the soft tissues.
• Adequate rests are provided so that the major connectors are
prevented from transmitting harmful horizontal or lateral forces.
• Anterior border of the maxillary major connectors should always
end in the valleys of the rugae and not on the crest of the rugae.
• Metal extensions from major connectors should lie in the embrasure
space in order to disguise the metal thickness.
• These should be made symmetrical and should cross the palate in a
straight line whenever possible.
• These should be designed in such a way that its margins do not cross
the bony prominences such as tori or soft tissue prominences.
• These should have support from other components of the framework
to minimize rotation of the prosthesis during function.
• These should be made of the alloy which is biocompatible.
• These should not interfere with the patient’s speech.
Beading of the maxillary cast means to scribe or indent a shallow groove
on the maxillary cast before duplication.
• Provide an excellent visible finish line.
• Provide intimate tissue contact and prevent collection of food particles
• Provide scope to the technician to reduce metal thickness on the
polished side in this area without compromising on the strength.
• Transfer major connector design to the investment cast.
The beading of the cast is accomplished with a spoon excavator and
has depth and width of 0.5–1.0 mm each. Depth of the beading varies
where the mucosal covering is thin such as over the midpalatal raphe
or the torus region. Beading should be 6 mm (minimum) away from the
gingival margin. When the denture is removed from the mouth, the
outline of the beading should be visible on the palatal tissue but there
should be no sign of inflammation. The intimate contact of the metal
major connector and the palatal tissue enhances the retention and
Designing of maxillary major connector
L. Blatterfein (1953) described five steps which should be followed
while designing maxillary major connectors. Primary impression is
made to form diagnostic casts and the displaceability of the palatal
tissues is thoroughly assessed.
Steps in designing are as follows:
Step 1: Outline primary bearing areas on the diagnostic cast. The
primary bearing areas are those that are covered by the denture
Step 2: Outline nonbearing areas on the cast. Nonbearing areas include
lingual gingival tissues within 5–6 mm of the teeth, midpalatal
raphe, palatal torus, tissues posterior to the posterior vibrating line.
Step 3: Outline the connector area.
Step 4: This step involves selection of the type of major connectors. The
selection depends on four factors namely rigidity, area of denture
base, indirect retention and patient’s comfort. Connectors should be
rigid so as to distribute functional stresses and should have
minimum bulk. Need for indirect retention influences the outline of
Step 5: Unification – joining of the denture base and the connectors.
Types of maxillary major connectors
(i) Single posterior palatal bar
(iii) Anteroposterior or double palatal bar
(iv) Horseshoe- or U-shaped connectors
(v) Closed horseshoe or anteroposterior palatal strap
Single posterior palatal bar (fig. 16-1)
• It is a narrow and half oval-shaped bar which is thickest in the centre.
• The bar is gently curved and its width is less than 8 mm.
• Sharp angles are best avoided at the junction of the palatal bar and
FIGURE 16-1 Single palatal bar.
• It is used to fabricate interim partial denture.
• It is used to replace one or two teeth on either side of the arch.
• It is not adequately rigid because of narrow width.
• It derives little vertical support from the hard palate.
• It can interfere with tongue function.
• It is not used in distal extension cases and for replacing anterior
Single palatal strap (fig. 16-2)
• Its width is more than 8 mm.
• It consists of thin wide band of metal.
• The width is increased as the edentulous span is increased.
• Sufficient rigidity is obtained using a 22-gauge plastic pattern.
• Bilateral or unilateral tooth-supported edentulous span (class III
• Sometimes, wide palatal strap can be used for unilateral distal
extension partial denture (class II).
• It has good rigidity and it resists torquing and bending stresses.
• It can be kept in thin sections without compromising rigidity.
• It results in enhanced patient comfort.
• It distributes stresses over a wide surface area.
• Soft tissue reaction may lead to papillary hyperplasia.
• Some patients may complain of excessive palatal coverage.
Anteroposterior or double palatal bar (fig. 16-3)
• It has an excellent rigidity due to strong L-beam effect (two bars
which lie in two different planes produce structurally strong Lbeam effect).
• Anterior strap is flat, located just posterior to the rugae region and is
narrower than the posterior strap.
• Posterior strap is thin and is at least 8 mm wide, located on the hard
• Lateral straps or bars are narrow. These are often 7–8 mm wide.
• This type of connector is used when the periodontal support of the
FIGURE 16-3 Anteroposterior major connector.
• In class I and class II situations with healthy abutment and good
• Connector of choice in cases of large midpalatal maxillary tori.
• It can be used in most of the partial denture situations.
• It has an excellent rigidity.
• It is a patient’s preference, as it has less palatal coverage.
• It derives less vertical support because of limited palatal coverage.
• It cannot be used in cases where the remaining teeth are
• It should not be used in cases of high narrow vault, as the anterior
• The patient may complain of discomfort in the anterior region.
Horseshoe-shaped or U-shaped connectors (fig. 16-4)
• These consist of a thin band of metal extending along the lingual
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