• White lesions on the mucosa are potentially dangerous and so the
patient should be sent to an oral pathologist for examination.
• Some white lesions on the mucosa are as follows:
Oral mucosa can be classified on the basis of their thickness as
Class 1: Firmly bound mucosa of uniform thickness which forms ideal
cushion for the basal seat of the denture.
(i) Soft tissues which are covered by thin, friable mucosa and are
(ii) Soft tissues which have mucous membrane twice the normal
thickness and may or may not be mobile.
Class 3: Excessively thick mucosa containing mostly redundant
tissues; tissues should be treated surgically or nonsurgically.
Oral mucosa can also be classified according to
• Basal seat should be having a uniform layer of soft tissue over the
• Ideal tissue will be quite firm and slightly resilient.
• Thin tissue covering can easily be damaged by the pressure from the
denture and too thick tissues will be too soft and may displace the
• Maxillary tuberosities are often enlarged with the movable fibrous
tissue, which affects the support for denture.
• Large tuberosities should be removed, if they are movable.
• Hyperplastic or flabby maxillary ridges also affect the stability and
• Best treatment is to remove it by surgery.
• Crest of the residual mandibular ridge is palpated for loose or firmly
• Soft tissues include the retromolar pad which is both soft and easily
• Pad does not support the denture but must be covered by the
denture, if a border seal is to be maintained.
Amount of remaining alveolar bone provides the height of the ridge
support of the denture (Fig. 2-3).
FIGURE 2-3 Height of residual alveolar ridge: (A) Class I –
adequate height; (B) Class II – moderate ridge; (C) Class III –
Class I: Adequate height of the ridge is present which provides good
denture support and best resists the lateral movement of the denture
Class II: Slight to moderate amount of resorption of the bone has
occurred but still adequately resists the lateral movement of the
Class III: Residual ridge has undergone almost complete resorption
and provides little or no resistance to the lateral movement of the
• Best form to prevent rotational movements
Class II: V-shaped ridge provides some vertical support for the
Class III: Knife-edged ridge provides little or no vertical denture
Classification based on the shape of the arch form given by House
FIGURE 2-4 Shape of the arch: (A) square-shaped arch
form; (B) tapered arch form; (C) ovoid arch form.
• Best form to prevent rotational movements
• Most favourable shape and provides best stability
• Offers lesser resistance to rotational movements
• Usually associated with a high-arched palate
• Comparatively less retention and stability due to less surface area
• Provides reduced surface area which lies perpendicular to the
• Because of its rounded shape, it provides little or no support to
Relationship between the upper and lower arches is examined as
FIGURE 2-5 Ridge relationship: (A) Class I ridge relationship;
(B) Class II ridge relationship; (C) Class III ridge relationship.
Classification of anterior arch relationship:
Class I: Normal anterior horizontal overjet of around 2–4 mm
Class II: Excessive horizontal overjet of more than 8 mm
• Mandible is less developed than the maxilla.
• Smaller jaws offer less support and retention.
Class III: Edge-to-edge incisal relationship
• It is due to overdevelopment of the mandible.
• Sometimes there is pseudo-class III relation which is habitual.
• It is often seen in a patient who has been without teeth for a period
of time and has a habit of chewing by using anterior part of the
Classification of posterior arch relationship:
Class I: Normal functional and nonfunctional cusp relationship
Class II: Associated with underdeveloped mandible
Class III: Associated with a large mandible or an underdeveloped
Amount of space available between the upper and lower ridges
determines the amount of space available to set the artificial teeth.
Based on the space in cross-section (Fig. 2-6), the interarch is
FIGURE 2-6 Interarch space: (A) Class I – interarch space;
(B) Class II – excessive interarch space; (C) Class III – limited
Class 1: Adequate interarch space to accommodate dentures.
Class 2: Excessive interarch space; distance between the teeth and the
supporting bone is excessive which decreases denture stability and
retention due to increased leverage.
Class 3: Interarch space is limited or less; difficult to accommodate
When teeth are lost gradually, there are chances that the ridges will
diverge (nonparallel) from each other. When ridges are not parallel to
each other, the dentures tend to slide over the basal seat when
occlusal forces are applied to them.
Class I: Both upper and lower ridges are parallel to each other;
provide best denture stability.
Class II: Either upper or lower ridge is divergent anteriorly. Either of
the dentures tends to slide forward.
Class III: Both upper and lower ridges are divergent anteriorly and,
therefore, tend to slide forward.
Vertical support and retention of the maxillary denture are partially
determined by the shape of the hard palate.
Classification of the hard palate based on shape (Fig. 2-7):
• Broad, flat with U-shaped palate; offers best vertical support
• Most favourable for retention and stability
• Gives lesser denture support and retention
• Offers little vertical denture support and retention
• Poor resistance to lateral forces
FIGURE 2-7 Shape of hard palate: (A) Class I – U-shaped
palate; (B) Class II – V-shaped palate; (C) Class III – flat
Soft palate determines the extent of additional area available for
retention as well as the width of the posterior palatal seal area.
Classification: Based on the angulations between the hard and the soft palate
• Soft palate is almost horizontal, curving gently downwards.
• This is most favourable, as it provides maximum tissue coverage for
• Muscular activity is minimal.
• Soft palate turns downwards at about 45° from the hard palate.
• Palatal coverage is less than that of class I.
• Palate turns downwards sharply at about 70° to the hard palate.
• Usually seen along with a deep V-shaped palate.
• This is least favourable, as the available space for the palatal seal is
FIGURE 2-8 Classification of soft palate: (A) Class I – soft
palate; (B) Class II – soft palate; (C) Class III – soft palate.
Denture construction is difficult in patients with sensitive palate, as
Class 1: No response to palpation; normal palate.
Class 2: Minimal response to palpation indicating the patient’s
Class 3: Hypersensitive palate which has violent response to
• These are the bony enlargements usually found at the midline of the
hard palate or lingual to premolar region of the mandible.
• Small tori normally do not present any problems in the denture
• The denture should always be relieved in this region so as to avoid
excess pressure over the thin mucosa covering the tori.
• Generally, surgery is avoided, but if the torus is so large that it
extends beyond the vibrating line and over part of the soft palate
then it should be removed or reduced in size, as it may interfere
with the development of the posterior palatal seal.
• Usually mandibular tori are removed surgically whenever feasible
FIGURE 2-9 Frequent location of tori: (A) Class III – palatal
torus; (B) Class III – mandibular tori.
• Class 1: Tori are absent or small and do not interfere with the use of
• Class 2: Ridges have tori that offer mild difficulty for adaptation of
dentures. Surgery may be optional.
• Class 3: Tori are excessively large, present undercuts. Surgical
• In some patients, the severely resorbed mandible has a cord-like soft
• These are easily displaceable labially, buccally and lingually.
• These do not provide stability and support for the dentures.
• These are painful when dentures are worn.
• These can be treated surgically.
• Favourable tongue is average sized, moves freely and covered by
• Tongue contributes in denture stability by controlling the denture
during functions such as speech, mastication and swallowing.
• During examination, tongue size and position are observed.
Class 1: Size of the tongue is adequate to fill the floor of the mouth
and there is adequate space for the lower denture.
Class 2: Tongue slightly overfills the floor of the mouth.
Class 3: Excessively large tongue.
• Enlarged tongue makes denture construction difficult.
• Impression making is difficult.
• Denture stability becomes a major issue, as any movement of the
denture tends to destabilize the denture.
Management in patient with large tongue
• Occlusal plane may be lowered.
• Increase intermolar distance.
• Avoid setting of the second molar.
If the tongue does not maintain the correct position, it is difficult to
attain the lingual seal in the lower denture.
Wright’s Classification (Fig. 2-10)
• Tongue lies in the floor of the mouth in the correct position.
• Tip of the tongue is relaxed and rests slightly below the incisal edge
• The lateral surface of the tongue contacts the lingual surfaces of the
posterior teeth and the denture base.
• Tip of the tongue turns either up or down.
• The lateral borders of the tongue are in correct position.
• Tongue is depressed into the floor of the mouth and is in retracted
• Tip does not touch the lower denture or ridge.
• Lateral border rests above the mandibular occlusal plane.
• Floor of the mouth will be raised and tensed.
FIGURE 2-10 Various tongue positions: (A) Class I; (B) Class
Malignant and premalignant changes
• Side and undersurface of the tongue are common locations for
• Biopsy is mandatory to confirm diagnosis.
• Surgical removal of the affected parts is usually the treatment of
• Frenal attachments are traditionally classified as high and low in
relation to the crest of the ridge.
• Unfortunately, this creates confusion; therefore, an alternative
Class I: Muscle or frenal attachment is close to the vestibule and
Class II: Muscle and frenal attachments are higher and closer to crest
Class III: Muscle or frenal attachment is too high. The attachment is at
or close to the crest of the ridge, which is unfavourable. Denture seal
is difficult and may interfere with retention of the denture. In such
cases, surgical intervention may be necessary.
• It can affect the prognosis of the mandibular denture.
• If the floor of the mouth is at or near the level of the ridge crest, the
retention and stability of the denture are less.
• Sometimes sublingual glands and mylohyoid regions spill on to the
ridge due to excessive ridge resorption.
Saliva can be classified on the basis of its quality and quantity.
Class 1: Normal quality and quantity of the saliva; ideal cohesive and
Class 2: Excessive saliva, more mucus or watery; difficulty in making
impression; also may cause gagging.
Class 3: Xerostomia; denture retention is a problem; more chances of
• Saliva is an important factor in denture retention.
• The amount and consistency of the saliva are noted.
• Thin: Favourable for denture retention.
• Thick: Ropy consistency tends to displace the denture.
• Excessive: Makes denture construction difficult and messy.
• Reduced: Reduced flow results in reduced retention of the denture.
• Salivary substitutes or oral moisturizers may be
Severe bony undercuts usually require surgical intervention, as these
tend to destabilize the dentures. However, unnecessary bone
reduction should be avoided such as in cases of mild undercuts.
Surveying of the diagnostic cast is essential in determining the depth
Class I: Bony undercuts are absent.
Class II: Small or unilateral mild undercuts, wherein the denture can
be placed by altering the path of insertion or relieving the pressure
Class III: Severe bilateral undercuts that are mostly corrected by
House classified palatal throat form as (Fig. 2-11) follows:
FIGURE 2-11 Palatal throat form: (A) Class I; (B) Class II; (C)
Class I: Large size and normal in form. This form consists of relatively
immovable band of resilient tissue 5–12 mm distal to the distal edge
Class II: Medium size and normal in form. It is a relatively immovable
band of resilient tissue which lies 3–5 mm distal to the distal edge of
Class III: Usually seen in small maxilla. The curtain of the soft tissue
turns down abruptly 3–5 mm anterior to a line drawn across the
palate to the distal edge of the tuberosities.
Lateral throat form (postmylohyoid space)
This area is observed when the patients retrude their tongue (Fig. 2-
FIGURE 2-12 Lateral throat form: (A) Class I; (B) Class II; (C)
Class 1: Approximately 0.5 inch of space exists between the
mylohyoid ridge and the floor of the mouth. This is most favourable
for retention of the lower denture.
Class 2: Less than 0.5 inch of space exists between the mylohyoid
ridge and the floor of the mouth. It is less favourable for retention of
Class 3: The mylohyoid fold is at the same level as the mylohyoid
ridge. Retention of the lower denture is almost impossible.
Geriatrics is defined as ‘the branch of medicine that treats all problems
peculiar to the ageing patient, including the clinical problems of senescence
Physiopathological conditions of ageing
Ageing is a normal physiological process and not an illness. A number
of gradual changes occur as age increases, such as:
• Increased desiccation of tissues
• Slowing of cell division, growth and tissue repair
• Decreased velocity and magnitude of neuromuscular function
• Increased breakdown of central nervous system (CNS)
A person’s values and attitudes change as his/her age advances. These
Motivational changes: Enthusiasm is less and often requires great
support, incentive and encouragement.
Physical performance and endurance: More tendencies to get fatigued;
muscle tone and coordination are inadequate for skilful
Family position: It plays an important part in the adjustment of older
• Oral mucosa and skin changes
• Residual bone and maxillomandibular relation changes
• Salivary flow changes and nutritional impairment
• Secretory cells in the skin become dry and less elastic.
• Edentulous mucosa is thin and tightly stretched, gets easily
• Reduction in oestrogen output (menopause) has atrophic effect on
• Reduction in surface area affects oral mucosa and skin.
• Skin appears loose and wrinkled.
• Patients have compromised mucosal support and may require
frequent application of soft liners.
Residual bone and maxillomandibular relation
Gross reduction of maxillary and mandibular residual ridges often
results in long-term denture wearing.
Several dentists attribute ridge reduction to disuse atrophy. However,
Changes in size of the basal seat
• Edentulous maxilla resorbs upwards and inwards. Thus, it becomes
smaller in all dimensions and the denture-bearing surfaces
• The mandible resorbs lingually and inferiorly in the anterior region
and buccally in the posterior region.
• This can affect the denture support and stability.
Changes occur in the vertical maxillomandibular relations with time
because of the residual ridge resorption and muscle changes.
• Tongue may become smooth and glossy, or red or inflamed.
• Vitamin B deficiency may result in sore or burning tongue.
• Tongue thrusting because of nervous tension can lead to sore
• Taste bud atrophy can lead to loss of appetite.
Salivary flow and nutritional impairment
• Skin dryness may indicate concomitant decrease of function of the
• Xerostomia may result from atrophy of salivary glands.
• Dry mouth offers little or no lubrication for the denture bases.
• It also decreases the retentive characteristics that are afforded to the
dentures by the hydrostatic nature of the saliva.
Gag reflex is a normal healthy defence mechanism which prevents
foreign bodies from entering the trachea. It is present since birth.
It is defined as ‘an involuntary contraction of the muscles of the soft
palate or pharynx that results in retching’. (GPT 8th Ed)
Classifications of causes include the following:
Chronic conditions such as a deviated septum, nasal polyps or
sinusitis and blocked nasal passages increase the likelihood of gag
Gastrointestinal tract problems such as chronic gastritis, carcinoma
of stomach, peptic ulcer and cholecystitis may increase irritability,
lower the threshold for excitation of the oral cavity and cause nausea
• In some patients, an abnormal gag reflex may be due to past
• Gagging as psychosomatic reaction may be active or passive and
can be modified by fear, anxiety and apprehension.
Visual, auditory and olfactory stimuli are extraoral factors that can
elicit the gag reflex, while dental prostheses and performance of
dental procedure represent intraoral stimuli.
Extraoral stimuli: Mere sight of a mouth mirror or impression tray or
an acoustic stimulus can initiate the gag reflex.
Intraoral stimuli: Certain regions in the oral cavity are extremely
sensitive to the tactile stimulus.
Heavy smoking, coughing and excessive consumption of alcohol are
some social causes of gag reflex.
Patient who gags repeatedly with denture becomes so intimately
associated with the denture that any procedure involving the denture
or in the oral cavity triggers the reflex.
• Marble technique: A method for treating the ‘hopeless gagger’ for
• An impression technique with modified custom tray for mild
• Acupuncture technique: Using pressure point on Neikuan point and
• Appleby and Day’s finger massage technique.
• Controlled breathing method.
FIGURE 2-13 Acupuncture technique.
• Have the patient rinse the mouth with cool water.
• When all such attempts fail, extraoral radiograph should be taken.
Excessive thickness, overextension or inadequate postdam should be
• Local anaesthetic is added to irreversible hydrocolloid material.
• Modified edentulous maxillary custom tray.
• Palateless or roofless denture (Fig. 2-14).
• Using elastomeric impression material for making impression.
FIGURE 2-14 Palateless denture.
Peripherally acting drugs: These are topical local anaesthetics. These are
applied in the form of sprays, gels or lozenges or by injection.
Centrally acting drugs: These are categorized as antihistamines,
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