• To correct this error, the upper buccal cusp and the lower lingual
cusp on the working side are reduced
• By doing this, the lingual inclines of the upper buccal cusp and the
buccal inclines of the lower lingual cusp are made less steep
• Grinding of the central fossa is avoided
FIGURE 10-10 Heavy contact on balancing side.
Selective grinding procedure of nonanatomic
• Gross premature contact in centric relation is removed by using an
• Occlusal interferences are detected in the lateral and protrusive
• Selective grinding is done on the occlusal surfaces of the teeth that
have been tipped or elongated during processing.
• In eccentric position, grinding is not done on the distobuccal portion of
• On the balancing side, all grinding is done on the lingual portion of
the occlusal surface of the upper second molar.
• Abrasive paste can be placed on the teeth on the articulator and the
lateral and protrusive movements are initiated.
• The abrasive paste mills the interfering contact and the procedure is
continued till smooth gliding movements of teeth are achieved in all
• Spot grinding may be required to eliminate small discrepancies in
centric relation after grinding with abrasive paste.
• Small discrepancies are identified using articulating paper or tabulator
ribbon and selectively grinded.
Intraoral methods to correct occlusal
Some of the commonly used methods are described below.
• Using the articulating paper alone does not give accurate indication
• Resiliency of the tissues sometimes allows the dentures to shift
which may produce false result with the articulating paper.
• When the articulating paper is placed on one side, the patient can
shift the jaw close to or away from the side.
• Placing articulating paper on both sides of arch simultaneously may
• Correlator which is a type of central bearing device with a spring is
used to detect occlusal prematurities.
• Pin attached in the mandibular mounting contacts with the metal
plate attached in the vault of the maxillary denture.
• The interceptive occlusal contacts are located with articulating
• Patient cooperation is very important.
• Coble device without the spring can also be used.
• Adhesive green wax is placed over the mandibular denture and the
patient is instructed to close in centric position.
• Points of penetration on the wax that occurs upon closure of the
jaws are detected and marked with lead pencil and relieved.
• Interferences can also be located in functional movements.
• However, chances of false markings are high during functional
movements as shifting of the dentures can take place over the
• This is an excellent method to detect occlusal prematurity in centric
• Abrasive paste when used over the occlusal surfaces of the teeth
mills the cuspal inclines to remove the premature contact.
• Shifting of the base as a result of premature contact results in
• Cusps that maintain the occlusal vertical dimension may be
• This type of paste is not selective.
Postinsertion instructions to denture patients
Patient education regarding the limitations of the denture as artificial
prosthesis simulating natural tissues is started from the first
appointment. Still at the time of denture insertion, many instructions
• Patient must be educated that appearance with the new dentures
will become more natural with time.
• Initially, the dentures may feel bulky and give a feeling of the
fullness in the lips and the cheeks.
• With the passage of time, the lips and cheeks will adapt to the
• Muscle tension will improve after the patient becomes more relaxed
• The patient is instructed not to compare his/her denture with others.
• Also, they should be advised to avoid exhibiting their dentures to
curious friends until they are confident.
• It will take at least 6–8 weeks for the new denture patient to chew
• Time is required for the establishment of new memory patterns for
both the facial muscles and muscles of mastication.
• The muscles of the tongue, cheeks and the lips must be trained to
keep the denture in place over the ridges during mastication.
• Initially, there will be excessive salivation with new dentures.
• Within few days, the salivary glands accommodate to the presence
of the dentures and the production of saliva.
• The patient is instructed to chew soft food from both sides of the
• Hard food should be avoided till the time the patient adjusts with
• The patient should be discouraged to incise the food between the
anterior teeth in front of the mouth.
• He/she is instructed to put the food towards the corner of the
• The patient is informed about the role of tongue in the stability of
lower denture during mastication.
• Speaking normally with new dentures requires practice.
• The patient is encouraged to read loud and repeat words or phrases
that are difficult to pronounce.
• They are encouraged to read newspaper aloud in front of the mirror
• The patient is educated on the importance of maintaining good oral
• The patient is instructed to brush dentures at least twice daily and
rinse dentures after every meal, whenever possible.
• Dentures are cleaned with a soft brush using liquid soap or
• Dentures should be brushed over the washbasin which is partially
filled with water or covered with wet cloth to prevent breakage of
denture on accidental dropping.
• Denture cleansers can be advised to remove stains from the
• The mucosal surface of the residual ridges and the dorsum of the
tongue should be brushed daily with a soft brush.
• The patients are discouraged to wear the dentures during the night.
• They are educated on the importance of rest to the tissues.
• The patients are instructed to keep the dentures in a container filled
with water to prevent drying and possible dimensional changes of
• The dentures should be removed to provide rest to the tissues
• The patients should also be discouraged on the continuous use of
denture adhesives and home reliners.
• The patients are educated on the need for periodic recalls.
Educating materials for patients
• The patients should be given written instructions about the
dentures, preferably in the patient’s language.
• The patients should be advised to read book or pamphlet regarding
Troubleshooting in complete denture prosthesis
Troubleshooting in complete denture prosthesis can be caused by
either of the following factors:
• Adverse intraoral anatomical factors (e.g. atrophic mucosa)
• Clinical factors (e.g. poor denture stability)
• Technical factors (e.g. failure to preserve the land area on the master
• Patient adaptational factors
All of the above-mentioned factors are important but by far the
patient adaptational factor is the most critical. Some patients are
positive with the treatment and some find it difficult to adapt to the
new prosthesis physically and psychologically. It is important to take
proper history and accurately diagnose the problem individually.
Troubleshooting in complete dentures usually arises after insertion of
Troubleshooting can be broadly divided into the following categories:
(i) Discomfort or pain with the dentures
• Discomfort related to impression surface of
• Discomfort related to the occlusal and polished
surfaces of dentures (Table 10-5)
• Discomfort related to possible systemic factors
• Due to decreased retentive factors (Table 10-7)
• Due to increased displacive factors (Table 10-8)
(iii) Inability to adapt to dentures (Table 10-9)
DISCOMFORT WITH DENTURES RELATED TO IMPRESSION
Discrete painful areas Pearls or sharp ridges of acrylic on
Pain on insertion and removal Denture is not relieved in the region of
Areas painful to pressure Faulty impression, damage to master cast,
warpage of denture base, lack of relief to
active frena, nondisplaceable mucosa over
Pain on swallowing Overextended lower denture Determine extent
Generalized pain over the denturebearing areas
Underextended denture base due to
overadjustment to the periphery
Lack of relief for frenum, muscle
attachments, pinching of tissues
Peripheral overextension resulting from the
impression stage and design error
Sore throat, difficulty in swallowing Posterior palatal area is too deep Removal of existing
DISCOMFORT RELATED TO THE OCCLUSAL AND POLISHED
Anterior or posterior premature
contacts, lack of balanced occlusion
Detect occlusal prematurity and adjust by
selective grinding; if the error is severe, take
new interocclusal record and remount
If no overextension is present, look for
protrusive slide from the centric
Detect deflective occlusal inclines of posterior
teeth and adjust by selective grinding
Lack of overjet Reduce the overbite; if appearance is
disturbed, rearrange the incisor
VDO is more If VDO is less than 1.5 mm, adjust by
selective grinding; if more than 1.5 mm,
For cheeks: The functional width of the
sulcus was not restoredFor lips: Poor
lip support/inadequate overjet
For cheeks: Restore functional width of
sulcusFor lips: Grind lower incisor to alter the
Tongue biting Teeth placed in the tongue space more
Remove lower lingual sulcus or reset teeth
Distobuccal border of the upper
denture is too thick and constraining
Use disclosing material to accurately define
area involved; relieve and polish
DISCOMFORT DUE TO POSSIBLE SYSTEMIC FACTORS
Burning sensation over the upper
Correction of any denture faults, may require
multivitamin drugs, nutrition and medical
dentures, complain of dry mouth
Advise citrus lozenges or artificial saliva
Difficult to manage; seek medical advice
Presence of herpetiform ulcers in
Suggest preventive remedy (e.g. acyclovir) but
Clicking of the TMJ on opening
Careful correction of vertical dimension of the
related to the support of upper
denture may be accompanied with
Rest to tissue; correct denture problem using
tissue conditioners and occlusal pivots; for
angular cheilitis advice antifungal and
Note: TMJ = temporomandibular joint.
LOOSENESS OF DENTURE RELATED TO DECREASED
Lack of peripheral seal Underextended borders in depth and
Consequences of ageing process,
increments using softened tracing
Side effects of drugs, patient on
radiotherapy, salivary gland disease
retention and minimize displacing
forces; artificial saliva can be
Lower posterior placed lingually, occlusal
plane too high, upper posterior placed too
far buccally, lingual flange of lower
convex, reduced neuromuscular control
Correct design faults, denture
Deficient impression, damaged master
cast, warped denture, overadjustment of
impression surface, residual ridge
Reline if design is satisfactory,
between the denture and tissues
are relieved before impression
LOOSENESS OF DENTURE RELATED TO INCREASED
in depth and width, slow rise of
inflammation at reflection of the
sulcus tissues, deep postdam on
Thickened lingual flange causes tongue to
lift the denture, thick upper and lower
labial flanges may produce displacement
Poor fit to supporting tissues Poor impression Reline if design is
Denture not in optimal space Molars on lower denture are placed
lingually, posterior occlusal table too broad
causes tongue biting, thick lingual flanges
encroaching in tongue space, excessive lip
pressure to lower anterior aspect, excessive
pressure from upper lip to the denture in
Occlusal errors Uneven tooth contacts causing tilting of the
Centric relation and centric occlusion does not
Ulceration labial to lower ridge Excessive overbite, lack or balance and
lower anterior tooth contact cause tilting
and soreness of lower ridgeLast molar is
placed too far over the retromolar pad
Occlusal plane is not oriented appropriately
and masticatory forces tend to move
dentures over the supporting tissues
Denture rocks over the prominence which
may be covered with inflamed tissues
Fibrous displaceable tissue Masticatory forces tend to cause the denture
to sink and tilt into the supporting tissues
INABILITY OF PATIENT TO ADAPT TO DENTURES
Clicking of dentures Excessive VDO, occlusal
interference, may lack skill with
Patient education, relieve occlusal interference,
adjust vertical or remake the denture
Unstable dentures Construct new denture
Jaws close too far Decreased VDO May increase up to 1.5 mm by relining or else
Excessive VDO Can remove up to 1.5 mm or else remake
Speech problems Cause may not be obvious Check the vertical dimension, check positioning
of the teeth, excessive palatal contour
Gagging Loose dentures, thick distal border
of upper denture, low occlusal
plane, palatal placement of upper
unacceptable, poor lip support
VDO decreased, labial fullness and
anterior tooth position inaccurate
Adjust correct tooth position, re-register jaw
Denture base not characterized to
Patient failed to comment during
try-in, change from old denture to
Accurate assessment of the patient’s aesthetic
requirements, ample time with the patient
during try-in, use available evidence such as
relatives photographs to assist
Denture cleansers are aids used in maintaining complete denture
hygiene. It is important for the patient to practise denture hygiene
regularly for better success of complete denture treatment.
Denture cleansers can be divided into the following categories.
• Safe and effective denture cleansing agent should be used by the
• Many denture cleansers have strong bleaching agent in them and if
used regularly for long, can cause discolouration of the denture
• Inexpensive, safe and effective denture cleansing solution has been
suggested by Buffalo School of Dental Medicine, New York.
• This solution consists of 1 teaspoon of sodium hypochlorite, 1 teaspoon of
• Sodium hypochlorite provides bleaching action to remove stains from
the dentures and is also an effective germicidal agent.
• Calgon is a water softener, which by its detergent action loosens food
• The patients are instructed to wash the denture with soft brush
under running water after chemical soaking.
• White vinegar can also be used overnight to remove calculus deposits
• Acetic acid present in white vinegar helps in decalcifying the
• Soft denture brush, soap or denture cleansing paste and water are used
effectively to clean dentures.
• Hard denture brush should be avoided, as it abrades the teeth and
• Gentle brushing with nonabrasive detergent or paste is
recommended for effective denture cleansing.
• These are new denture accessories.
• Sonic cleaners employ vibratory energy and not ultrasonic energy to
• Sonic cleaners effectively remove calculus from the dentures.
• It is also observed that sonic cleaner when used with sodium
hypochlorite is more effective than when sodium hypochlorite was
• An occlusal pivot is an elevation placed on the occlusal surface of
the molars to limit the mandibular closure by acting as a fulcrum.
• The occlusion of the complete denture should be checked after 24 h.
• Burning sensation of the anterior palate in a new denture wearer is
due to insuf icient relief of the incisive papilla.
• Midline fracture of the dentures is mainly because of thick frenum
not relieved in the denture, wide deep notch in the midline, teeth
set too far buccally and excessive resorption.
Rationale for Relining Complete Dentures, 190
Problems Associated with Relining
Preparation of the Tissues, 190
Open Mouth Relining Technique, 190
Closed Mouth Relining Technique, 191
Advantages of Rebasing Over Relining, 195
Residual alveolar ridges tend to resorb with time at variable rate in
different individuals. The rate of ridge resorption is higher in females
than in males. With resorption, the adaptation of the denture with the
tissues is altered and hence it requires continuous maintenance.
Relining and rebasing are two techniques which are used to maintain
adaptation of the dentures to the tissues.
Relining is defined as ‘the procedures used to resurface the tissue side of a
removable dental prosthesis with new base material, thus producing an
accurate adaptation to the denture foundation’. (GPT 8th Ed)
Rebasing is defined as ‘the laboratory process of replacing the entire
denture base material on an existing prosthesis’. (GPT 8th Ed)
Indications for relining or rebasing
• Immediate dentures which were made 3–6 months before
• Poor fit of the denture base to the ridges because of resorption
• The patient cannot afford remaking of the dentures
• When mental or physical health of the patient does not permit
• If ridges are excessively resorbed
• If the soft tissues are highly abused
• Patients with temporomandibular joint problems
• Unsatisfactory jaw relationship
• Fit of the prosthesis is improved
• Soft liner can be used, if needed
• Not used in case of excessive resorption
• Chances of altered jaw relationship during the process
• Cannot correct occlusal arrangement
• Cannot alter aesthetics or jaw relations
Rationale for relining complete
• To re-establish the correct relation of the denture to the basal tissues
• To restore the lost occlusal and maxillomandibular relationships
• To restore retention and stability of the denture
Problems associated with relining
• Denture base almost always becomes thicker after relining.
• Maxillary denture is displaced anteriorly and, therefore,
oversupports the lips after relining.
• Plane of occlusion may be altered.
• It may result in colour difference between the original denture base
and the new relining material.
Relining is the procedure of adding additional acrylic resin to the
tissue surface of the original denture base to replace the lost oral
• Excessive hyperplastic tissues should be surgically removed.
• Any irritating cause to oral mucosa is removed.
• Adequate rest to the supporting tissues.
• Dentures are left out of mouth for at least 2–3 days before making
• Daily massage of soft tissues is recommended.
• Pressure areas in the denture should be relieved.
• Minor occlusal prematurities are removed by selective grinding
• Correct posterior palatal seal should be established.
• Minor border inadequacies, if any, are corrected.
Carl O. Boucher’s Reline method (1973)
• Existing dentures are used as recording bases.
• Jaw relation is recorded after making maxillary and mandibular
• In the maxillary denture, posterior palatal seal is recorded with
• About 1 mm of space is provided in the tissue surface of the
• The denture borders are reduced by 1 mm to allow space for impression
material to form a new border.
• Similarly, the denture borders and the tissue surfaces of the lower
• Modelling plastic handle is made over the anterior teeth to facilitate
• Adhesive tape is applied over the polished surface of the denture.
• Border can be moulded with modelling plastic.
• After this, zinc oxide eugenol impression paste is loaded over the tissue
surface of the dentures and placed in the mouth.
• The patient is instructed to pull his/her lip down and open his/her
• These actions help the impression to be moulded over the border of
• Impression is made with selective pressure technique.
• It is possible to verify the centric relation record.
• Interocclusal record made with plaster is reliable.
• This technique requires more clinical and laboratory time.
• This technique is difficult to master.
Closed mouth relining technique
1. F.W. Shaffer’s technique (1971)
• Centric relation is recorded before the impression is
made using modelling compound or wax.
• Denture is relieved in large undercut areas and 1.5–
• Denture borders are reduced by 1–2 mm, except the
posterior border of the maxillary dentures.
• A large part of palatal portion of the maxillary denture is
removed to improve visibility of the maxillary
denture during impression making (Fig. 11-1).
• Border moulding is done using modelling plastic.
• Zinc oxide eugenol impression paste is used for
• During border moulding and impression making,
the patient closes his/her mouth lightly into the
interocclusal record that was previously made.
• The impression of the exposed palatal portion of the
upper denture is made by quick-setting plaster.
• Opening of the palatal portion of the maxillary
denture allows better seating.
• Premade interocclusal record helps in orienting the
dentures during impression making and mounting.
• Two-step impression procedure reduces the chances
of anterior shifting of the maxillary dentures.
• Possibility of forward movement of maxillary
• Wax interocclusal record is not reliable.
• It is difficult to reline both dentures at the same
2. N.J. Hansen’s technique (1964)
• Existing centric occlusion and intercuspation are
used as means to seat the dentures.
• Denture borders are prepared as in the abovedescribed technique.
• Even in this technique, palatal portion of the
• The palatal portion is outlined and reduced to half
the thickness of the denture base.
• Holes are drilled at 5–6 mm interval inside this
groove and slowly the portion is removed (Fig. 11-
• Green stick compound is used for border moulding.
• Impression is made with Kerr’s impression wax.
• Impression is made in two steps and the impression
of the labial flange and crest of ridge is made in the
• Two-step impression technique reduces the chances
of extreme forward movement of the maxillary
• It is difficult to manipulate the impression wax.
• Errors of existing centric occlusion can lead to
3. J.F. Bowman’s technique (1977)
• Existing centric relation is used to seat the dentures.
• Denture is prepared as in the above-described
• Labial and palatal flanges of the dentures are perforated.
• Perforation is made to decrease the pressure during
• No specific impression material is recommended.
4. L.G. Jordon’s technique (1971)
• Existing centric occlusion is used to seat the
• Denture is prepared as in the above-described
• Denture periphery is reduced to create flat border.
• A large opening is made in the palatal portion of the
• Adhesive tape is attached over the buccal and labial
surfaces of both dentures, 2 mm short of the denture
• Using a knife-edged stone, deep grooves are cut
into the labial and buccal surfaces of the dentures at
the junction of the impression material and filled
• Impression plaster or zinc oxide eugenol paste is used
for impression making for the first step.
• Impression plaster is used to make impression for the
• Same as Shaffer’s technique.
• Existing errors of centric occlusion can result in
5. N.S. Javid et al. technique (1985)
• This technique is based on the use of tissue
• The patient is instructed not to wear the dentures
• Centric occlusion in the old denture is carefully
examined and if any error is detected, it is
• The centric relation should coincide with the centric
• The denture borders and the tissue surface of the
denture are adequately reduced for tissue
conditioning material (Fig. 11-4).
• The surface is dried before impression material is
• Minimum thickness of tissue conditioning material
is placed over the tissue surface of the denture and
then inserted in the patient’s mouth.
• Once the material sets, the denture is removed from
the mouth and the excess material is trimmed using
• The patient is instructed regarding care of the
relining material before dismissing him/her.
• When the patient returns after 3–5 days, the denture
is re-examined for denuded areas.
• Any denuded area is marked with indelible pencil
and the pressure areas are relieved before next
application of the tissue conditioners.
• The material is changed periodically within 1 week.
• This is done till the tissues return to clinically healthy
• At this time, the patient is scheduled for final
• All the tissue conditioning materials on the tissue
side are replaced by new ones.
• Zinc oxide paste or light body polysilicones can also be
• Once the impression is satisfactory, it is poured
• The maxillary cast is mounted on the semiadjustable articulator using facebow record.
• The mandibular cast is mounted using interocclusal
• The relined dentures are replaced by the new
• Dentures are finished and polished in conventional
• Dentures are inserted in the patient’s mouth and
occlusal interference, if any, is detected and
corrected by selective grinding.
FIGURE 11-1 Large parts of palatal portion are removed for
FIGURE 11-2 Preparation of denture borders and palatal
portion of denture: (A) denture borders reduced by 2 mm; (B)
FIGURE 11-4 Tissue conditioners applied over the
impression surface of the denture.
Rebasing is defined as ‘the laboratory procedure of replacing the entire
denture base material on an existing prosthesis’. (GPT 8th Ed)
Indication and contraindication of rebasing are similar to relining.
Rebasing refers to the procedure of replacing all the denture base
• Impressions are made and the cast is poured in the
• The cast with the denture is mounted on an
instrument such as Hooper duplicator.
• This instrument maintains the relationship of the
• The original denture base is removed.
• The original teeth mounted in the duplicator are
rewaxed in their previous positions on the cast.
• Denture is then processed in the laboratory in
• Impressions are made and the cast is poured in the
• Cast is not separated from the denture.
• The cast is placed into the lower half of the flask.
• The silicone mould material is painted over the
denture before investing. This creates a flexible
• Flasking is completed in conventional manner.
• The flask is opened, once investing is completed.
• Because of the silicone mould, it is easier to separate
• Denture base is trimmed completely and the teeth
are replaced into the indentation.
• Separating medium is applied over the cast and the
mixed resin is packed into the space.
• Denture is cured, finished and polished in
• Finished dentures are remounted to check for any
3. Articulator Method (Fig. 11-7)
• Impression is poured immediately.
• Maxillary cast is mounted on articulator using
• The mandibular cast is mounted using interocclusal
• If occlusal discrepancy exists, it is identified and
• The complete denture base is reduced leaving 2 mm
• The trimmed teeth are placed back on the
articulator and waxed without altering the vertical
• The denture is then processed in conventional
FIGURE 11-5 Denture is indexed into Hooper duplicator.
FIGURE 11-7 Articulator method.
Advantages of rebasing over relining
• There is no colour difference between the old and new resin.
• Problem of release of strain from processing an old base is avoided.
• Thickness of the base is better controlled.
• It has an additional laboratory step.
• There are chances of displacement of teeth during waxing-up.
• Tissue conditioners are used in functional reline technique.
• The major drawback of rebasing complete dentures is chances of
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