Important classifications & tabular columns in Complete Denture

 

1. Classification of Soft palates:

Class 1	Horizontal & demonstrates little muscular movement. Most favourable condition, as it allows more tissue coverage for the palatal seal.
Class 2	Soft palate makes 45° angle to the hard palate. Tissue coverage for posterior palatal seal is less than that of class 1 condition.
Class 3	Soft palate makes 70° angle to hard palate. Tissue coverage for posterior palatal seal is minimum. A ‘V’ shaped palatal vault is usually associated with class III soft palate.

2. Classification of lateral throat form (retromylohyoid fossa):

Class 1 (deep)	It indicates that the anatomical structure will accommodate a fairly long and wind flange. Ideal throat form.
Class 2 (moderate)	It is about half as long and narrow as class 1 and twice as long as class 3.
Class 3 (shallow)	Class III has minimum length of thickness. The border usually ends 2-3 mm below the mylohyoid ridge.

3. House classification of tongue size:

Class 1	Normal size, development and function. Sufficient teeth are present to maintain this normal form.
Class 2	Teeth have been absent long enough to permit a change in the form and function of tongue.
Class 3	Excessively large tongue.

4. Wright's classification of tongue position:

Class 1	Tongue lies in the floor of the mouth with tip forward and slightly below the incisal edges of the mandibular anterior teeth. Ideal position of the tongue.
Class 2	The tongue is flattened and broadened but the tip is in a normal position.
Class 3	The tongue is retracted and depressed into floor of the mouth, with the tip curled upward or assimilated into the body of the tongue.

5. Stress bearing area of maxilla & mandible.

6. Mouth movements and their corresponding condylar movement.

Movement	Working condyle moves
Laterotrusion	Laterally and outwards
Laterosurtrusion	Laterally and upwards
Laterodetrusion	Laterally and downwards
Lateroprotrusion	Laterally and forwards
Lateroretrusion	Laterally and backwards

7. Difference between closest speaking space & freeway space.

Closest speaking space	Freeway space
Described by Silverman	Described by Thompson and niswonger
Closest speaking space measures the vertical dimension when the mandible and muscles involved are function of speech. It is the space between upper and lower teeth when sounds like eh, s, j are pronounced	It establishes vertical dimension when the muscles and mandible are in rest position.
It is dynamic position established when muscles are in state of function.	It is static position established when muscles are in state of rest.
It is about 1-2mm, when measured in the premolar area	It is about 2-4mm when measured in the premolar area
The speaking space increases when there is small vertical dimension	The freeway space increases when there is reduced vertical dimension.

8. Clinical features of increased & decreased vertical dimension.

Increased vertical dimension	Decreased vertical dimension
Decreased freeway space (Normal range= 2-4mm) Pain and clicking in the TMJ. Diffuse pain on ridge. Reversible soft tissue changes and irreversible ridge resorption. Increased lower facial height. Cheek biting Stretching of facial muscles.	Increased freeway space Sagging of the corners of the mouth Thinning of lips Obstruction of eustachian tube. Muscular imbalance Facial height decreases Angular cheilitis.

9. Classification of articulators:

Class I (Simple holding instruments capable of accepting a single static registration)	Eg: Slab articulators, Hinge joint, Barndor, Gysi simplex.
Class II (Instruments that permit horizontal as well as vertical motion but do not orient the motion of TMJ via face bow transfer)	Class IIa- Eccentric motion permitted based on average or arbitrary values. Eg: Mean value articulator. Class IIb- Limited eccentric motion is possible based on theories of arbitrary motion. Eg: Monson’s, Hall’s articulator. Class IIc- Limited eccentric motion is possible based on engraving records obtained from the patient. Eg: House’s articulator.
Class III (Permit horizontal, vertical positions and also accept face bow transfer.	IIIa- Accept a static protrusive registration and they use equivalents for other types of motion. Eg: Hanau H, Dentatus. IIIb- They accept static lateral registration and they use equivalents for other types of motion. Eg: Ney, Teledyne Haunau University series, Trubite, Panadent.
Class IV (They accept 3-dimensional dynamic registration)	IVa- The condylar path registered cannot be modified. Eg: TMJ articulator, stereograph. IVb- They allow customization of the condylar path. Eg: Stuart instrument gnathoscope, pantograph, Denar.

10. Treatment for deflective contacts in both anterior and posterior teeth.

Deflective contacts	Occlusal correction
Posterior teeth 1.Deflective contact is only in centric relation 2.Deflective contact is both in centric and eccentric positions	-Reduce fossa or marginal ridge -Reduce both fossa and cusp.
Anterior teeth When incisal edge of lower anterior touching the maxillary lingual fossa in centric relation only.	Reduce the lower incisal edges.
Incisal edge of lower anteriors touching the maxillary lingual fossa both in centric and eccentric relations.	Deepen the lingual fossa of upper teeth and reduce the incisal edges of lower teeth.
Deflective contacts occurring on working side	BULLS law- Upper buccal cusp & lower lingual cusp made shorter without deepening the central fossa.

For Atwood's classification of root resorption, click the link below...

https://www.blogger.com/blog/post/edit/4923003805564511941/6330678008591988062

If I missed any classification, let me know in the comment section.