Radiographs and clinical examinations are important for assessing periodontal disease. Radiographs identify bone loss and other factors. Clinical exams measure probing depth, recession, mobility and inflammation. Microbiological tests identify pathogens while immunological tests detect bacterial antigens. Investigations of oral lesions associated with HIV include ELISA, Western Blot and PCR tests. Radiographs and percussion help evaluate endodontic-periodontal lesions. Tests for halitosis include organoleptic assessment and measuring volatile sulfur compounds.

1. INVESTIGATIONS IN PERIODONTAL DISEASE

2. CONTENTS
 Assessment of periodontal disease
 Clinical investigations
 Radiographic investigations
 Microbiological investigations
 Immunological and biochemical investigations
 Other investigations for periodontal assessment
 Lab investigations
 Investigations of oral lesion associated with HIV
 Investigations of endodontic periodontal lesions
 Investigations for halitosis

3. ASSESSMENT OF PERIODONTAL DISEASE
 Radiographs play a important role in the investigation of periodontal disease
 Radiographic images aid the clinician in identifying the extent of destruction of
alveolar bone , local contributing factors , and features of periodontium that
influence the prognosis
 The clinical investigation may include periodontal probing , gingival index , mobility
charting , and also may be used to evaluate the amount of attached gingiva
 The clinical examination and the diagnostic image may give a complete diagnosis of
periodontal disease

4. CLINICAL INVESTIGATIONS
 Gingival bleeding-gingival bleeding is done using a periodontal probe BOP
indicates periodontal stability . Color and texture are the visible signs of
inflammation
 Gingival temperature-the periotemp probe used to detect pocket temperature
difference of 0.1c. Healthy sites have low temperature as compared to the
periodontal diseased sites
 Periodontal probing-used to assess the pocket depth, attachment levels
gingival recession , width of attached gingiva , nature of soft tissues , BOP, and
presence of plaque and calculus
 Tooth mobility assessment- millers(1985) evaluation of tooth mobility
NO movement is seen 0
First distinguishable signs of movement 1
Crown deviates within 1mm of normal position 2
Mobility is seen and tooth moves 1mm in any
direction or rotated in socket
3

5. PRICHARD (1972)
1. Slight mobility
2. Moderate mobility
3. Extensive movement in lateral or mesiodistal direction combined with vertical
displacement in the alveolus
WASERMAN et al ( 1973)
1. Normal
2. Slight mobility : less than 2mm of bucco lingual movement
3. Moderate mobility : upto 2mm movement buccolingually
4. Severe mobility : more than 2mm of buccolingual movement
NYMAN et al ( 1975)
Degree 0 = horizontal mobility or mesidistal of less than 0.2mm
Degree 1 = horizontal or mesiodistal mobility of 0.2-1mm
Degree 2 = horizontal or mesiodistal mobility of 1-2mm
Degree 3 = horizontal or mesodistal mobility exceeds 2mm or vertical mobility is seen

6. Radiographs are helpful in the evaluation of following features
 Amount of bone present
 Condition of the alveolar crests
 Bone loss in the furcation areas
 Width of the periodontal ligament space
 Local irritating factors that increase the width of periodontal disease
calculus
poorly contoured or overextended restorations
 Root length and morphology and crown-to-root ratio
 Open interproximal contacts( food impaction)
 Anatomic considerations
position of the maxillary sinus in relation to the periodontal deformity
missing , supernumerary , impacted or tipped teeth
 Pathological considerations like caries , periapical lesion , root resorption

7.  Endo perio lesions
 Integrity of lamina dura for placement of bone grafts
 Interdental bone(pattern of bone loss)
 Evaluation of cemental tears
 Systemic conditions causing bone destruction
 Assessment of bone quality for implant placement
 Surgical planning for placement of bone grafts

8. DIFFERENT RADIOGRAPHIC INVESTIGATIONS FOR PERIODONTAL DISEASE
Conventional radiography
1. Intraoral periapical radiographs
2. Bitewing radiographs
3. Occlusal radiographs
4. Orthopantomograms
Newer imaging techniques
1. Cone beam computed tomography

9. INTRAORAL PERIAPICAL RADOGRAPHS
 Detection of apical infection / inflammation
 Assessment of periodontal status
 After trauma to the teeth and associated alveolar bone
 Evaluation of apical cysts and other lesions within the alveolar bone
 Evaluation of implants postoperatively
 Vertical bony defects , periodontal ligament space and periodontal status can be assessed

10. BITEWING RADIOGRAPHS
 Alveolar crestal height is accurately determined
 The relation of the CEJ to the alveolar crest can be accurately determined
 Early crestal bone loss in the posterior region Is found

11. OCCLUSAL RADIOGRAPH
to determine the medial and lateral extent of the disease eg: cysts ,
malignancy
periapical assessment of upper and lower anterior teeth
assessment of the condition of the antral floor
detecting the presence of unerupted canines

12. ORTHOPANTOMOGRAMS
to get the status of entire supporting bone an extraoral radiograph such as panoramic
radiograph is taken
Periodontal bone loss and periapical involvement
Assessment for the placement of dental implants

13. CONE BEAM COMPUTED TOMOGRAPHIC IMAGING
 The three dimentional imaging of the CBCT gives better visualization of the some bony
defects which are not well demarcated on the conventional images like periapical or
interproximal radiographs
 CBCT gives a complete assessment of a complex vertical defects , craters , furcations ,
buccal and lingual plate loss
Panoramic axial
Parasagittal coronal

14. IMAGING FEATURES OF A PERIODONTAL DISEASE
1:
2:
Interproximal alveolar bone crest with slight
loss of alveolar bone height
Horizontal bone loss and the crest of buccal
, lingual cortical plates resorbes

15. Severe vertical bony defect seen in molars
and canine region
Severe loss of bone at the furcation area
with widening of pdl

16. LIMITATIONS OF INTRAORAL IMAGE
Periapical and bitewing radiographs may give an incomplete details about the
periodontal status
They have the following limitations
 They give a two dimentional view of the three dimentional
structure
 These images typically show less severe bone destruction than is actually
present
 Does not demonstrate soft tissue to hard tissue relationship and thus
provide no information about the depth of the pocket

17. MICROBIOLOGICAL INVESTIGATIONS
These test are used to identify pathogens
 Serve as a indicator of disease initiation and progression
 Determine which periodontal sites are at high risk for destruction
 Helps us to know the healing response
1. Bacterial culturing
2. Direct microscopy

18. IMMUNOLOGICAL AND BIOCHEMICAL INVESTIGATIONS
Utilize antibodies that recognize specific bacterial antigens to detect target
microrganisms .
the diagnostic procedure include
1. Direct immunofluorescent microscopy assay
2. Indirect immunofluorescent assay
3. Flow cytometry
4. ELISA
5. Membrane assay
6. Latex agglutination
Other investigations
1. Genetic susceptibility test
2. Detection of elastase-to detect the amount of enzyme in GCF sample under UV light
3. Nucleic acid probes
4. DNA DNA hybridization Molecular biology
technique

19. OTHER INVESTIGATIONS THAT FORMS PART OF PERIODONTAL
ASSESSMENT
 Recession
 Attachment loss
 Tooth mobility
 Furcation involvement
 Plaque levels (gingival index)
 Sensibility test
 Trauma from occlusion
 Probing depth can be used to assess the periodontal tissue breakdown

20. LAB INVESTIGATIONS
Based on the systemic status various tests may be indicated
 Bleeding time determination
 Clotting time determination
 Prothrombin time investigation
 Biopsis
 Nutritional status evaluation
 Hemogram
 Blood sugar investigation
 Thyroid function tests

21. INVESTIGATION OF ORAL LESION ASSOCIATED WITH HIV
INFECTION
A screening test
 Non quantative detection
 ELISA test
A confimatory test
 Western blot assay
 DNA polymerase chain reaction
 Viral culturing
 HIV DNA PCR
Rapid HIV antibody test
 The single use diagnostic system(suds)
Viral load
 Reverse transcriptase PCR

22. INVESTIGATIONS OF ENDODONTIC – PERIODONTAL LESIONS
TESTS
1. Percussion - tenderness to percussion is an indicator of periradicular inflammation .
Abnormal reaction to percussion is indicative of inflammation of the periodontal
ligament
2. Palpations - digital palpations in the mucosal tissues is helpful in detecting
periradicular abnormalities and localized swelling can also be detected throught this
test
3. Pulp testing - used to check the vitality of the pulp common pulp vitality tests are heat
, cold , electric and cavity test
4. Radiographs - radiographic interpretations of periapical and periodontal lesions is of
clinical importance in suggesting the cause of a lesions

23. INVESTIGATIONS FOR HALITOSIS
Volatile sulfur compounds are the main cause of halitosis which include
hydrogen sulfide , methyl mercaptan , dimethyl sulfide
 Organoleptic method
oral cavity odor
breath odor
tongue coating
nasal breath odor
 Gas chromatography
 Portable volatile sulfide monitor
 Saliva incubation test
 Electronic nose