This document discusses various methods of classifying partially edentulous arches. It describes Osborne and Lammie's classification system of tooth-borne, mucosa-borne, and combination support. It also details Kennedy's classification system of four classes based on the location of edentulous areas. Finally, it outlines Applegate's rules for standardizing the classification process based on factors like tooth extractions and replacements.

1. classification

2. Classifications of partially edentulous
arches are important for the following
reasons
1- To formulate a good treatment plan.
2- To anticipate the difficulties commonly to
occur for that particular design.
3- To communicate with a professional about a
case.
4-To improve communication between the
dentist and the laboratory technician

3. Osborne and Lammie's proposed simple
classification according to the type of support
into three classes:
I. Tooth-borne (Support)
II. Mucosa-borne (Support)
III. Combination of mucosa-borne and tooth
borne (Support)

4. A. Tooth support B .Mucosa
support
C. Mucosa-tooth support

5. Kennedy’s classification
ClassI : A Bilateral edentulous areas located
posterior to the remaining natural teeth.
Class II : A unilateral edentulous area located
posterior to the remaining natural teeth.
Class III : A unilateral edentulous area with
natural teeth remaining both anterior and posterior
to it .
Class IV : A single bilateral edentulous area
located anterior to the remaining natural teeth.

6. Class I Class II
Class III Class IV

7. O.C.Applegate's Rules
Rule I: Classification should follow rather than precede any extractions of
teeth that might alter the original classification.
Rule 2: If the third molar is missing and not to be replaced, it is not
considered in the classification.
Rule 3: If a third molar is present and is to be used as an abutment, it is
considered in the classification.
Rule 4: If a second molar is missing and is not to be replaced, it is not
considered in the classification (for example, if the opposing second molar is
likewise missing and is not to be replaced).
Rule 5: The most posterior edentulous area (or areas) always determines the
classification.
Rule 6: Edentulous areas other than those determining the classification are
referred to as modifications and are selected by their number.
Rule 7: The extent of the modification is not considered, only the number of
additional edentulous areas.
Rule 8: There NO modification areas in class IV arches. If there are posterior
edentulous areas beside the anterior area the former will determine the class
rather than the anterior one.

9. A- Class IV
B- Class II modification 2
C- Class I modification 1
D- Class III Modification 3
E- Class III Modification 1
F- Class I modification 2
G- Class IV
H- Class II
I- Class III modification 6