1. Phonetics refers to the sounds of speech and their production. Normal speech relies on the proper functioning of the lungs, vocal cords, oral cavity, and brain. 2. Consonant sounds are important for dentistry and can be classified based on their place of articulation. Sounds like S, T, and D involve the tongue and hard palate, while sounds like TH use the tongue and teeth. 3. Several aspects of denture design can affect speech, such as denture thickness, the vertical dimension of occlusion, and the positioning of teeth. For example, teeth that are too far back can cause difficulties producing F and V sounds. Phonetics is useful for evaluating denture fit

1. NORTH BENGAL DENTAL
COLLEGE & HOSPITAL
PHONETICS IN
PROSTHODONTICS
By- SK AZIZ
IKBAL

2. Definition
 Speech:- The expression of or the ability to express
thoughts and feelings, by the articulation of words.
 Phonetics:-The branch of linguistics that deals with the
sounds of speech and their production, combination,
description, and representation by written symbols.

3. 1. The motor( lungs, associated muscle that supply the air).
MECHANISM OF SPEECH
PRODUCTION
Normal speech depends on proper functioning of 5
essential mechanism
2. The vibrator ( vocal cord that give pitch to the tone).
3. The resonator ( consist of the oral,nasal, pharyngeal cavity and
paranasal sinuses).

4. 4. The enunciators or articulators(
lip, tongue, palate and teeth)
5. The initiator( motor area of the brain)

5. TYPES OF SPEECH
 1.VOWELS: a,e,i,o,u. they are voiced sounds,
 2.CONSONANTS: may be either voiced or
produced without vocal cord vibration, in which
case they are called breathed sounds. eg: p, b, m, s,
t, r, z etc…
 3.COMBINATION: Is blend of a consonant and
vowel, articulated in quick succession that they are
identified as single phonemes.
EX:- WORD

6.  Consonant sounds are most important from the
dental point of view. They may be classified according
to the anatomic parts involved in their formation:
(1) Palatolingual sounds, formed by tongue and hard or
soft
palate,
(2) Linguodental sounds, formed by the tongue and teeth,
(3) Labiodental sounds, formed by the lips and teeth, and
(4) Bilabial sounds, formed by the lips.
CLASSIFICATION OF CONSONANTS BASED
ON THE PLACE OF THEIR PRODUCTION

7.  PALATOLINGUAL SOUNDS FORMED
1. Tongue and hard palate
2. Tongue and rugae
3. Tongue and soft palate

8. TONGUE AND HARD PALATE
Word like S,T, D, N and L belong
to this category
S- the sound ‘s’ as in sixty six- is
formed by a hiss of air as it escapes
form the median groove of the
tongue when the tongue is behind
the upper incisor- Sears
If groove is decreased s is softened towards sh
(Lisping)
If groove is deep a whistling will be
heard when s is pronounced

9. CLINICAL SIGNIFICANCE
1. Thus we can say that the sound S can be used to
check the proper placement of the anterior teeth
2. Also the thickness of the
denture base can be adjusted in
case the sound S is not
produced correctly
3. Silverman’s closest speaking space also used
this word t o establish and check a proper
vertical dimension of occlusion

10. Rugae and tongue
T, D, N and L word
Rugae area is very important for the
production of these sounds.
Tongue must be placed firmly against the
anterior part of the hard palate for the
production of these words.
CLINICAL SIGNIFICANCE
 If teeth too lingual – T will sound like D
 If teeth too forward - D will sound like T

11. TONGUE AND SOFT PALATE
Consonant k, ng and g are representative of the
palatolingual group of sounds.
Sound is formed by raising the back
of the tongue to occlude with the soft
palate and then suddenly depressing
the middle portion of the back of the
tongue realising the air in a puff
CLINICAL SIGNIFICANCE
 If the posterior borders are over extended or if there is no tissue
contact k becomes ch sound.

12. LINGUODENTAL SOUNDS
Consonant Th is representative of the linguodental
group of sounds
Dental sounds are made with the tip of the tongue
extending slightly between the upper and lower
anterior teeth.
 Sound is actually made closer to the alveolus (the ridge) than to the tip of
the 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. CLINICAL SIGNIFICANCE
 If about 3mm of the tip of the tongue is not visible,
the anterior teeth are probably too far forward,
 If more than 6mm of the tongue extends out between
the teeth when such sounds are made, the teeth are
probably too lingual

14. LABIODENTAL SOUNDS
 F and V are representatives of
the labiodental group of sounds.
 Formed by raising the lower lip
into contact with the incisal
edge of the maxilliary anterior
teeth.
CLINICAL SIGNIFICANCE
Upper anterior teeth are too short (set too high up), V sound will be more
like an F.
If they are too long (set too far down), F will sound more like a V.

15. BILABIAL SOUNDS
 B,p and m are representatives of the bilabial
group of sounds.
 Formed by the stream of air coming from the
lungs which meets with no resistance along its
entire path until it reaches the lip.
CLINICAL SIGNIFICANCE
 Used to asses the correct interarch space
 Correct labiolingual positioning of the
anterior teeth
 Labial fullness of the rims can also be
checked

16.  Also called as the speaking method
determining sliverman closest
speaking space
 Sibiliant sounds like S and M is
used.
 S sound gives the approximate
closest speaking space
 M sound gives us the freeway space
 Approximately 2mm of space must
be there between the two occlusal
rims
PHONETICS IN RECORDING JAW RELATION

17. 1. Thickness of denture
2. Antero-posterior position of teeth
3. Vertical dimension of occlusion
4. Width of dental arch:
5. Relationship of upper teeth to the lower anterior
teeth by “S-POSITION
CLINICAL SIGNIFICANCE OF ‘S’ SOUND

18. 1. Denture thickness and peripheral outline
2. Vertical dimension
3. Occlusal plane
6. Anteroposterior positioning of teeth
5. Post dam area
7. Width of dental arch
4. Relationship of the upper and lower teeth
PROSTHODONTIC IMPLICATION IN DENTURE DESIGN
AFFECTING SPEECH

19. DENTURE THICKNESS AND PERIPHERAL
OUTLINE
 If the denture bases are too
thick.
 Lisping will occur with the
word like S,C and Z
 Palatolingual sounds most
affected. (T,D).
VERTICAL DIMENSION
•Bilabials are mostly affected P,B and M
•If both rims touch prematurely it indicated excessive vertical dimension.
•In try in stage teeth clicking will be heard.

20. OCCLUSAL PLANE
 Labioldental sounds F and V are affected.
 If occlusal plane is too high the correct
positing of the lower lip is difficult
 If the occlusal plane is too low there is
overlap of the lower lip on the labial surface
of upper teeth
ANTERIORPOSTERIOR POSITIONING OF TEETH
 F and V sounds are hampered.
 labiopalatal positions of the teeth is very important
 Teeth if placed to palatally the lower lip will not meet the insical edge of
the upper teeth.

21. POST DAM AREA
 Palatolingual consonants are affected (K, NG
and G)
 Thick post dam areas will irritate the dorsum of
the tongue
 Patient feels nausea like effect while speaking
 If inadequate the plosive sound of the word is
hampered
 This area is very important for singers who
wear complete denture
WITDH OF DENTAL ARCH
 If teeth are set into an arch that is too narrow the tongue will be cramped
 Consonants like T, D, N K and S are affected

22. RELATIONSHIP OF THE UPPER AND LOWER INCISORS
 The chief concern is the S
CH, J and Z sound.
 These sounds need a near
contact of the upper and
lower teeth so that the air
stream is allowed to pass.

23. TERMINLOGIES RELATED TO
SOME SPEECH DISTURBANCES
1. APHASIA (DYSPHASIA): Means defective speech due
to damage of cortical area required for speech making.
(Broca’s area, Wernicke’s area).
2. DYSARTHRIA: Motor speech problems caused, not due
to sensory loss or mental retardation.
3. SPEECH AND LANGUAGE RETARDATION: Delay
in acquistion of communicating skills

24. REFERENCES
1. John. Sharry. Complete denture Prosthodontics 3rd
edition; Phonetics.
2. Zarb- Bolender:Speech consideration with complete
dentures ;Prosthodontic treatment For Edentulous
Patients.
3. Fenn, Clinical Dental Prosthetics, 3rd edition pg 138.
4. Chierici, Lawson; Clinical speech consideration in
prosthodontics. J Prosthet dent;1973;29;1:29-39.
5. Robert Rothman; Phonetic consideration in denture
prosthesis, J Prosthet Dent;1961;11:214-223).
6. Meyer M Silverman :The speaking method in measuring
vertical dimension; J prosthet dent 1953;3:193-199.