3.9 Methods for examination of chewing and speech function

What is Gnathodynamometry?

Method that investigates chewing function by measuring biting and pressing forces

what does Gnathodynamometry help determine?

The moment when the patient experiences pain in the periodontium

how many models of gnathodynamometers are available? give examples

• over 30

• example - Black, Eckermann, Kleitmamann and Haber

what did Habers research conlude?

1. Men’s periodontal endurance is greater than womens

2. In each tooth, pain results in different values of masticatory forces

What are the two types of chewing methods that are used to assess tooth function?

Static and dynamic chewing methods

what other methods are used to asses tooth function other than static and dynamic chewing methods?

• Agapovs

• Boyanov

• Kurlyandski

Static method

conditional number that defines the comparative functional value of every tooth according to the other teeth and the whole dentition

simpler - each tooth has a numerical value that helps compare its function to other teeth in the mouth.

• The number represents how much a tooth contributes to chewing efficiency compared to the rest.

• It is a static method, meaning the evaluation is done without movement, based on a fixed analysis.

Dynamic method

Assessing the functional value of teeth during actual chewing or stimulated chewing activities, considering movement and interaction of teeth and jaws

Agapovs chewing coefficient

Boyanov’s chewing coefficient

Kurlyanaski’s chewing coefficient

• Static - functional method

• Coefficient of every tooth

• Total 160 coefficients

• Additional columns are the values in cases with damages periodontium; 25%, 50%, 75% and more than 75%

How many groups makes up the dynamic method?

• group I - chewing tests

• group II - Graphic methods

• group III - Combined methods

What does the Group 1 - chewing test of the dynamic method consist of?

• Chewing effectiveness (Christensen 1923) - 5g coconut to be chewed by 50 chewing movements

• Chewing capacity (Gelman, 1932) - 5g almond to be chewed for 50 seconds

• Chewing ability (Rubinov, 1956) - 0.8g hazelnut to be chewed till initiation of swallowing reflex

What does group II - Graphic method of the dynamic method entail?

• Masticatiography - record of the mandible movements

• Miography - method for registration of the volumetric changes in the muscles during functional movements

• Miotonoethry - Method for registration of the changes in the muscle tonus

• Masticatiodynamometry - method for registration of chewing forces, generated by the chewing muscles

• Electromiography - oscilographic registration of the bio potentials of teh functional muscles

What does group III - Combined methods of the dynamic method entail?

Electromiomasticatiography (Rubinov) - Combination between masticatiography and electromyography: registration of the mandible movements and the bio potentials of the functional muscles

What are the two types of methods for examining speech function?

• Acoustic methods

• Somatic methods (sound articulation)

What are the types of ways to examine speech function Acoustically?

1. Auditory method - Subjective method that relies on personal impressions to assess speech

2. Phonography - Graphic method used to register speech problems after prosthetic treatment

3. Sonography (acoustic spectrography) - method involves spectral analysis of speech

What are the types of ways to examine speech function Somatically (sound articulation)?

1. Palatography - technique that identifies which parts of the palate are engaged when pronouncing different sounds.

   • Record made through this method is called palatogram

   • Static palatography, observes tongue print using black paste, can be done directly onto the palate (direct palatography) or onto pseudo palate (indirect palatography)

What is the phonetically neutral zone?

Specific area within oral cavity where tongue can rest comfortably without affecting the pronunciation of speech sounds. The position will allow for ease of articulation and helps maintain clarity in speech production

What is Anthropometry and what are the references?

Anthropometry is the scientific study of human body measurements and proportions

In dentistry the references are:

• Trichion (hairline) to glabella upper third (smooth area between eyebrow, above nose)

• Glabella to subnasale middle third (where nasal septum meets upper lip)

• Subnasale to menton lower third (lowest point of the chin)

What is the frankfurt horizontal line?

• anatomical reference line used in craniofacial measurements

Where does the frankfurt horizontal line connect?

Connects the point on the lower margin of the eye socket (porion) and the highest point on the external auditory meatus (tragion)

what is the frankfurt horizontal line used for?

• used to assess the position and orientation of the skull and facial structures

where is frankfurt horizontal line commonly used?

in orthodontics, maxillofacial surgery and other related fields

what is ala tragus line?

• imaginary line used as reference in facial analysis and plastic surgery

• Connects ala of nose (wing like structure) to the tragus of ear (small cartilahe in front of ear canal)

• Used to asses facial symmetry and proportions, particularly in relation to nose and ear

where does ala tragus line connect?

connect ala of nose (wing like structure) to the tragus of the ear (small cartilage in front of ear canal)

what is ala tragus line used for?

to assess facial symmetry and proportions, particularly in relation to the nose and ear

what are the aesthetic criteria for teeth?

• face

• lips

• gingiva

• alignment

• proportions

• shape and form

• colour

What other aspects should be looked at when investigating chewing efficiency and force distribution?

• sagittal curve (speed line)

• Transversal curve (Wilson curve)

• Villains curve

What is the geometrical method (1910)?

• It is a visually descriptive method

• It basically talks about how the form of the ehad will determine the shape of the teeth

What is harmony in geometrical method?

Harmony means there is correlation between the shape of the teeth (incisors) and the form of the head

What is Nelsons triad in geometrical method?

Concept in dentistry that involves the interrelationship between the shape of the teeth, the form of the face and form of the dental arch

It suggests the three factors are interconnected and influence eachother:

• Shape of teeth

• form of the face

• form of the dental arch

WHEN AND WHO WAS THE CONCEPT OF ESTHETIC SEGMENTS (ES) introduced?

Ralev in 1993

What is the concept of esthetic segments on about?

The segments categorize the visible upper teeth based on their esthetic importance when smiling

Describe ES1, ES2, ES3, ES4

1. ES1 - includes both upper central incisors, which are considered most prominent and important teeth for aesthetic smile

2. ES2 - comprises all upper central and lateral incisors

3. ES3 - all upper incisors and canines

4. ES4 - encompasses all visible upper teeth when smiling. It considered the aesthetic impact of the entire upper dental arch during a smile

what is the golden ration?

0.618 : 1 : 1.618

Smile is considered aesthetically pleasing if each tooth in that smile (starting from midline) is approximately 60% of size of tooth immediately mesial to it

What are some design software’s for face/smile?

• smylist

• visagismile

• carasmilestudio

• cerec software

• planmeca romexis smile design

• DaVincis software