Dr Prince Kumar (Phonetics)

1. Phonetics IN Complete Denture
Dr Prince Kumar
DEPARTMENT OF PROSTHODONTICS

2. PHONETICS IN
COMPLETE DENTURE

3. MECHANISM OF SPEECH PRODUCTION
MOTOR
VIBRATOR
RESONATOR
ARTICULATOR
INITIATOR

4. PHYSIOLOGIC VALVES IN SPEECH PRODUCTION
The speech mechanism include three
principal physiologic valves.
Valve I : the glottis
Valve II : the palatopharangeal
valve
Valve III : the orifice of the mouth.

5. THE TONGUE
• The tongue is the principle articulator for speech.

6. Functional Tongue Classification
 The occupational tongue.
 The still tongue
 The normal tongue
 The habitual tongue.

7. CLASSIFICATION OF SPEECH
SURDS
SONANTS
CONSONANTS

8. CONSONANTAL ARTICULATION
 Stops
eg:- p,b,t,d
 Fricatives
eg:-f,v
 The Affricatives
eg:- j,ch
 Diversions
eg:- m,n

9. ENGLISH CONSONANTS: - THEIR POSITION AND MODE OF
PRODUCTION
The production of English consonants involves six valves:-
1. Bilabial
2. Labiodental
3. Linguodental
4. Lingeoalveolar
5. Linguopalatal
6. Linguovelar

10. Bilabial Sounds
 The sounds b, p and m are made by contact of the lips.
 Insufficient support of lips by teeth and / or denture base can cause these
sounds to be defective.

11. Labio-dental Sounds
 The labio-dental sounds f and v are made between the insial edge of
upper incisors and lower lip.
 If the upper anterior teeth are too short (set too high up), the V sound
will be more like an ‘f’. If they are too long (set too far down), the f will
sound more like a v.

12. Linguodental Sounds
 Dental sounds (eg. Th) are made with the tip of the tongue extending
slightly between the upper and lower anterior teeth.
 Careful observation of the amount of tongue that can be seen with the
words – this, that, these and those will provide information as to the labio-
lingual position of the anterior teeth.

13. Linguoalveolar Sounds
 Alveolar sounds (eg. t, d, s, z,& l) are made with the valve formed by
contact of the tip of the tongue with the most anterior part of the palate
 The important observations when these sounds are produced are the
relationship of the anterior teeth to each other.
 A failure of the incisal edge to approach exactly end to end indicates a
possible error in the overlap of the anterior teeth.

14. The S Sound
 From a dental point of view, the S sound is the most interesting one.
Because its articulation is mainly influenced by the teeth and palatal part
of the maxillary prosthesis
 In nearly all languages of the world, S is a common speech sound.

15. Linguovelar sounds
 The truly palatal sounds (example: year, she, insion and onion) present less
of a problem for dentures.
 The velar sounds (k, g and ng) have no effect on dentures, except when
the posterior palatal seal extension encroaches on the soft palate.

16. PALATOGRAM
• It’s a recording of tongue-palate contact during the production of given
sound.
• Palatograms are the area of tongue contact for a given sound displayed on
an artificial palate through a medium of non scented talcum powder.
• Prerequistes for making a palatogram-

17. Speech tests
 The phonetic aspect of denture construction should be checked at the time of the
waxed try-in when it is possible to alter palatal contour to accommodate speech
articulation.
 The trial denture evaluation should not be considered complete until a phonetic
test has been made.
 The first test is of random speech.
 The second test is to test specific speech sounds.
 In the third test, the patient is asked to read a short paragraph containing an
abundance of s, sh, and ch sounds.

18. THE MANDIBULAR MOVEMENT OF SPEECH AND THEIR
SEVEN RELATED VALUES
• By recording and interpreting certain mandibular movements of speech,
the patient reveals seven informative facts that are directly related to
restoring the original mandibular tooth position, phonetic sharpness, and
occlusal harmony.
• These are:-
– The vertical overlap
– Horizontal overlap
– Lower anterior tooth display
– Class of occlusion
– Maximum usable vertical dimension
– Index for incisal guidance
– The maximum serviceable cusp height

19. • The closest speaking space to measure the vertical dimension in this
speaking method must not be confused with free way space of
determining the vertical dimension.
• The free way space establishes vertical dimension when the muscles
involved are at complete rest, and the mandible is in its rest position.
• The closest speaking space measures vertical dimension when the
mandible and muscles involved are in the active full function of speech.

20. • The “F”or “V’ and ‘S’speaking anterior tooth relation – Pound
and Murrel:
• Insisal guidance is established by arranging the anterior teeth in the
occlusal rims before recording the vertical dimension of occlusion.
• Maxilary anteriors – F and V
• Mandibular anteriors - S
• Speech in establishing vertical dimension at rest:

21. Communication problems associated with cleft
palate:-
 Clefts of the lip and palate affect speech in two major ways:
 The voice quality becomes deviant, and the articulation is impaired.
 The voice quality is that of excessive nasality.
 They have more trouble with the plosives, fricatives and affricatives
 Voiced sounds seem to be easier than the unvoiced ones, but the
consonant blends present considerable difficulty.
 The distortion errors are primarily due to nasal emission, the person
snorting the sounds out of his nose.

22. Speech evaluation following obturator
placement:-
 The prosthodontist may require the assistance of a speech pathologist.
 Cleft palate patients will invariably require speech therapy
 Patients often exhibit hypernasality
 The obturator is adjusted to the point where the patient can produce a
clear “p” and a sustained “f” or “s” sound without emission of air
through the nose
 Several authors suggested that the sustained pressure required for the
“s” phoneme may be a reliable method of evaluating the effectiveness
of the obturator.
 Whereas greater intraoral pressure may be required for stop-plosives,
such as “p”, the sustained pressure required for “s” mitigates the
compensatory elevation of the tongue to assist with closure.

23. PROSTHODONTIC CONSIDERATIONS OF SPEECH:
• 1) Effect of denture thickness:
• If the thickness of the denture base covering the palatal area is more, then
lipsing of the sounds will occur.
• Allen (1958) found that an additional thickness of 1mm in the anterior
palatal area made speech awakward and indistinct
• The denture base thickness in the postdam area
• The thickness of the lingual flange in the anterior region

24. • 2) Effect of tooth position on speech:
• If upper anteriors are too short of occlusal plane
• 3) Effect of dental arch form on speech:
• If the arch is narrow, faulty articulation of the consonants like ‘t, d, l, n, s, r
will results, where lateral margins of the tongue makes contact with
palatal surfaces of the upper posterior teeth.
• The correction can be done by the slight thickening of the denture base in
the center of the palate, so that tongue does not have to extend up as far
as into narrow palatal vault.

25. • 4) Effect of vertical dimension on speech:
• Fymbo (1936) - increased vertical dimension results in difficulty in
pronouncing sounds like ‘b, m, p, f, v’.
• Landa (1947) recommended various phonetic tests to determine proper
vertical dimension using sounds such as ‘s, c, z’.
• Silverman (1956). He established the “closest speaking space” and used
this as clearance area between the dentures.
• The bilabial sounds like ‘m’ is helpful in determining the vertical
dimension.

26. • 5) Whistle and Swish sounds:
• Silverman (1967) stated that the Whistle and Swish sounds are produced
during speech due to air abnormally passing over the tongue and through
the interincisal space. These sounds may be caused due to decreased
overjet.
• 6) Effect of denture esthetics on speech:
• Speech is some times related to patients emotional attitudes towards the
denture esthetics.
• Lawson (1973) stated that when there is any change in patient mouth,
then there will be anxiety reaction and to overcome this problem they
shows abnormal movement of lip, jaws, and tongue during speech.