Overview :

The Navy Periodontal Disease Index Index (NPDI) was developed as part of the Navy Periodontal Screening Examination, along with the Navy Plaque Index. It is composed of a gingival and a pocket scores. The NPDI score can be used to determine the level of treatment required by the individual patient.

Teeth examined (US designation):

(1) 3

(2) 9

(3) 12

(4) 19

(5) 25

(6) 28

Substitutions:

• If 3, 12, 19 or 28 is missing, then substitute the next most posterior tooth.

• If 9 or 25 is missing, then substitute the nearest incisor in the arch. If all of the incisors are missing from the arch. If all incisors are missing from the arch, then substitute a cuspid.

Gingival Score

Each tooth is examined for evidence of inflammatory change, which constitutes one or more of the following findings:

• any change from normal gingival color

• loss of normal density and consistency

• slight enlargement or blunting of the papilla or gingiva

• tendency to bleed upon palpation or probing

Pocket Score

With a calibrated periodontal take 6 measurements of each designated tooth:

(1) mesial facial surface

(2) middle facial surface

(3) distal facial surface

(4) mesial lingual surface

(5) middle lingual surface

(6) distal lingual surface

pocket score =

= MAX(score taken at the 6 probing sites)

Generating the NPDI

tooth score =

= (gingival score) + (pocket score)

NPDI score =

= MAX(all 6 tooth scores)

NPDI total =

= SUM(all 6 tooth scores)

Interpretation:

• minimum tooth score: 0

• maximum tooth score: 10

• minimum NPDI score: 0

• maximum NPDI score: 10

• minimum NPDI total: 0

• maximum NPDI total: 60

Grossman FD, Fedi PF Jr. Navy Periodontal Screening Examination. J Am Soc Prevent Dentistry. 1973; 3: 41-45.

Hancock EB, Wirthlin MR Jr. An evaluation of the Navy periodontal screening examination. J Periodontol. 1977; 48: 63-66.