Advanced Diagnostic Aids
Dr. Khushbu mishra
HKE’s S.N Dental college,
Limitations of conventional periodontal diagnosis
Advances In Clinical Diagnosis
Advances In Radiographic Assessment
Advances Microbiologic Analysis
Advances In Characterizing The Host Response
• Definition : Diagnosis is defined as identifying the disease
from an evaluation of history, signs and symptoms, laboratory
tests and procedures.
• Importance :
a. It identifies and indicates the nature of etiological factors
b. Indicates the nature of pathological processes
c. It is essential for treatment planning
types of diagnosis
Provisional differential comprehensive
Diagnostic aids in periodontics conventional
• Tissue destruction ( Periodontitis)
Loss of connective tissue
attatchment loss bone loss
Gives historical evidence of damage
Identify and quantify current clinical signs of inflammation
• Does not provide cause of condition
• Susceptibility of patient
• Cannot reliably identify sites with ongoing periodontal
• Cannot differentiate whether response to therapy is positive or
• Periodontal disease is localised and multifactorial.
• Consideration should be given microbiologic
in addition to clinical and radiographic parameters.
• The focus is now disease prevention, early discovery, and
intervention to minimize treatment, thus enabling the most
• Diagnostic modalities available to clinicians today expand
greatly on the foundation of a comprehensive visual
assessment, which has been and will be the cornerstone of the
• Aids used in clinical diagnosis
i. Conventional probes – regular examination
ii. Millimeter probes – for gingival bleeding
iii. Pressure sensitive probes
Other clinical diagnostic aids
i. Filter papers- for measuring GCF
ii. Periotron 6000- for measuring GCF
iii. Olfactometer- for mouth odors
iv. Mobilometer- for tooth mobility
v. PSR- for faster screening and recording of PD
• Aids used in radiographic diagnosis
i. IOPA radiographs
• Aids used in microbial diagnosis
i. Direct examination
a. Light microscopy
b. Dark field microscopy
ii. Culture tests
a. Aerobic culture
b. Anaerobic culture
• Aids used in immunological diagnosis
i. Immunofluorescense- direct and indirect
ii. Polymerase chain reaction
iii. Latex agglutination
iv. Flow cytometry
• Biochemical diagnosis
i. Studies for prostaglandins
ii. Studies for collagenase
• Other diagnostic aids
i. study casts
iii. N-benzoyl-DL- arginine 2- naphthylamide (BANA)
Advanced diagnostic aids
• Advanced periodontal probes
i. Automated controlled force probes
ii. Thermal periodontal probes
• Advanced diagnostic aids in periodontal radiography
i. Digital radiography
ii. Substraction radiography
iii. Digital substraction radiography
iv. Transmission radiography
v. Magnetic resonance imaging
vi. Computerized tomography
vii. Nuclear medicine bone scan
• Advanced diagnostic aids in microbiologic analysis
i. Advances in culturing technique
ii. Advances in immunodiagnostic methods
iii. Advances in enzymatic methods
iv. Advances in nuclear biology- PCR and DNA probes
• Advanced diagnostic aids in charting the host response
i. Assessment of inflammatory mediators and products
ii. Assessment of tissue breakdown products
iii. Assessment of host derived enzymes
• Advanced diagnostic aids to determine periodontal disease
i. Crevicular contents
• Products of bacteria
• Products of host cells and host immunity
ii. Markers in peripheral blood
• Neutrophil functional profile
• Monocyte responsiveness to LPS
• Circulating antibodies to plaque bacteria
iii. Detection of specific periodontal pocket bacteria
a. DNA probes
b. BANA hydrolysis
c. Antibody techniques
Advances in clinical diagnosis
• Degree of gingival inflammation
a. redness and swelling
b. gingival bleeding
• Gingival bleeding ∞ plaque accumulation
(Greenstein G et al 1981)
size of inflammatory infiltrate
probability of losing attatchments
(Lang et al.1991)
• Thermal probes are sensitive diagnostic devices for measuring
early inflammatory changes in gingival tissue.
(Kung et al 1990)
• Commercially available system periotemp probe
• Individual temperature differences are compared with those
expected for each tooth and higher temperature pockets are
signaled with a red emitting diode.
• Subgingival temperature at diseased sites is increased as
compared to normal healthy sites
• Elevated subgingival temperature ∞ attatchment loss
& elevated propertions of
( Haffajee et al.)
• Most widely used
• Clinical assessment of connective tissue destruction in
• Gold standard – recording changes in periodontal status
• Probing depth is measured from the free gingival margin
(FGM) to the depth of the probable crevice.
• not the most objective measure of loss of periodontal tissues
• CAL is a more objective measure of loss of Existing
• CAL also does not give any indication of current disease
• When interpreting the PD and CAL measurements made with
conventional periodontal probes, it is important to consider
that these values depend on the inflammatory state of the
Classification of periodontal probes depending
1.First generation probes:(conventional probes)
Conventional manual probes that do not
control probing force or pressure and
that are not suited for automatic data
eg: Williams periodontal probe
University of Michigan’O’ probe
Goldman Fox probe
Merritt A and B probe
2.Second generation probe:
(Constant force probe)
Introduction of constant force or pressure sensitive probes
allowed for improved standardization of probing.
e.g.: Pressure sensitive probe
Constant pressure probe
3.Third generation probe:(Automated probes)
Computer assisted direct data capture was an important step in
reducing examiner bias and
also allowed for generation probe precision.
e.g.: Toronto probe
Interprobe, Foster Miller probe.
4.Fourth generation probes:(Three dimensional probes)
Currently under development, these are aimed at recording
sequential probe positions along a gingival sulcus.
An attempt to extend linear probing in a serial manner to take
account of the continuous and three dimensional pocket that
is being examined.
5.Fifth generation probe:(Noninvasive)
Three dimensional probe.
Basically these will add an ultrasound to a fourth generation
If the fourth generation can be made, it will aim in
addition to identify the attachment level without
e.g.: Ultra sonographic probe.
Tip is 0.4mm
Sleeve- edge provides reference
to make measurements
Coil Spring; provides constant probing force
Computer for data storage.
• Disadvantages of Florida probe.
Lack of tactile sensitivity
Fixed probing force
Underestimation of deep periodontal pockets.
Other electronic probes:
Improvised Florida PASHA probe
Foster Miller probe
Toronto Automated ( difficult to reproduce patient head
position and in 2nd and 3rd Molar area.)
• To screen dental patients to facilitate the detection of mild
forms of periodontal diseases and to identify individuals who
have previously undetected periodontitis.
• It is designed for general dental practitioner to identify the
patient’s requiring periodontal care and to determine the type
of care required.
• Based on the worst site per sextant.
• If one or more sextants show significant signs of disease,
clinician is advised to do a complete periodontal examination
Advances in Radiographic Assessment
• Dental Radiography are traditional method to assess
destruction of alveolar bone.
• Problems with conventional Radiography:
Variation in projection geometry
Variation in contrast and density
Masking by other anatomic structures.
They are very specific but lack sensitivity.
• Computerized images.
• Image property almost equal to conventional radiographs
• 1/3rd to half reductions in radiation dose.
• Well established in medicine
• Introduced in Periodontal diagnosis
• Principle: Serial radiographs converted to digital images
superimposed composite image– Quantitative changes
• Changes in density and volume of bone
a. can be detected as lighter areas (bone gain)
b. Dark areas (bone loss)
• Perfect accuracy at a lesion depth of 0.49 mm
( Grondhal et al 1988)
• Limitations: needs paralleling technique and accurate
Diagnostic Subtraction Radiography
• Positioning device during film exposure
specialized software designed for digital image subtraction
using conventional personal computers
• Applies an algorithm that corrects for the effects of angular
alignment discrepencies and provides some degree of
flexibility in imaging procedure
Computer Assisted Densitometric Image Analysis
light transmitted through Radiographs
signals from camera
gray scale images
camera interfaced with image processor
• Offers objective method for following alveolar bone density
changes quantitatively over time.
• Higher sensitivity
• High degree of reproducibility
• Computed Tomography scanning is widely used in the
evaluation of the implant patient
• A thin fan beam of X-Rays rotates around the patient to
generate in one resolution a thin axial slice of the area of
• Multiple overlapping axial slices are obtained by several
revolution of the X-ray beam until the whole area of interest is
• With the help of a computer and sophisticated Algorithms
these slices are then used to generate a three dimensional
digital map of the jaw which help in evaluation of the implant
• Specialized software can be used to generate appropriate views
that best depict the dimensions of the jaws and the location of
important anatomic structures.
• DENTAL VIEWS OBTAINED FROM A CT SCAN
» 1. AXIAL
» 2. PANORAMIC
» 3. CROSS-SECTIONAL. Views of the Jaws.
ADVANTAGES of Computed Tomography
1. True cross sections offer a precise and detailed
evaluation of the height and width of the ALVEOLAR
2. The images can be adjusted and printed without
magnification, facilitating measurements directly on the
prints or films with standard rulers.
3. Various anatomic structures can be visualized and
analyzed at all the Coordinate axis.
– Images of the entire arch several edentulous areas can be
visualized with single examination.
– The Bone and soft tissue contrast and resolution are
excellent for the diagnostic task.
DISADVANTAGES of Computed Tomography
specialized equipment and setting.
Radiologists and Technicians need to be knowledgeable
of the anatomy, anatomic variants and pathology of the
jaws as well as considerations pertinent implant treatment
higher radiation dose to the patient as compared to other
modalities used during implant treatment planning.
it delivers radiation to whole arch.
Metallic Restorations can cause ring artifacts that impair
the diagnostic quality of the image, it is challenging to the
patients having heavy metallic restored dentition.
CONE-BEAM COMPUTED TOMOGRAPHY
• Cone-Beam Computed Tomography (CBCT) is a new
imaging modality that offers significant advantages for the
evaluation of implant patients.
• The 3- D CBCT images canbe combined with high precision
3D visible light (photographic) surface images to create a
virtual patient that accurately displays both hard and soft tissue
• This multi- modal image image visualization enables a
treatment platform that allows assessment of the patient’s
present condition, planning and stimulation of treatment
options, progress monitoring and evaluation of outcomes.
Advances in Microbiologic Analysis
• Strong evidence for actinomycetemcomitans (Aa),
Porphyromonas gingivalis (Pg), and Tannerella forsythia
• Other organisms that are thought to have etiologic role are
Camphylobacter rectus, Eubaterium nodatum,
Fusobacterium nucleatum, Peptostreptococcus micros,
Prevetolla intermedia and Prevetolla nigrescens,
• Microbiologic tests( that can identify)
a. Can support diagnosis of various Periodontal disease.
b. Can tell about initiation & progression
c. Active & Inactive
d. Can also be used to monitor Periodontal therapy
whether it is suppressed/ eradicated.
• Several studies
(-)nce of Pathogens better periodontal health
(+)nce of pathogens periodontal disease
• Bacterial culturing
• Direct microscopy
• Immunodiagnostic methods
• Enzymatic methods
• Diagnostic assays based on molecular biologic techniques
• Historically, widely used in characterizing composition of
• Plaque sample anaerobic culture
Advantage: 1. clinician can obtain absolute or relative count
2. invitro method for antibiotic susceptibility
• Limitations :
i. Culture can grow only live bacteria.
ii. Sensitivity is low
iii. Requires sophisticated equipment and experienced personnel.
iv. Time consuming
• Dark field
Direct microscopy alternative to culture methods
• Ability to assess morphology
& motility in plaque.
• Dark field microscopy seems an unlikely candidate as a
diagnostic test of destructive periodontal diseases.
• It employs Antibody
specific bacterial antigen
• Various procedures:
a. Direct & indirect immunofluorescence assays
b. Flow cytometry
d. Membrane assay
e. Latex agglutination
• Direct IFA: AB conjugated with Fluorescein marker +
Bacteria ( Antigen) = Immuno complex
• Indirect IFA: Primary AB + Bacteria= Immune Complex+
Secondary Fl conjugated AB
Cytofluorography/ Flow cytometry
Bacterial cells+ species specific AB
+ Secondary FL Conjugated AB
Introduced in flowcytometer
Bacterial cells is separated into
single cell suspension-
passes through the tube
Cells identified by lasers
• merits :
labels bacterial cells species specific antibody
fluorescin conjugated secondary
ELISA= Enzyme Linked Immunosorbent Assay
Similar AB and Antigen reaction, but the fluorescence is read
using a photometer.
Evalusite: commercially available kit to detect Aa,Pg and Pi.
Well with precoated antibody + Sample
to be tested= immune complex
Specific antigen bind to the antibody +
Secondary antibody added.
Immunofloresence dye bound to
Substrate added which changes the
color of the solution
Amount of florescence checked by
• Latex Agglutination Test
Latex beads coated with species specific AB when beads come
in contact with specific species in sample they bind and
agglutination occurs clumping of beads is visible test
Simple and Rapid testing
Higher sensitivity and specificity.
• Bacteria release specific enzymes. Certain group of species
share common enzymatic profile.
e.g. Tf, PG, Td, and Capnocytophaga species release trypsin
• Enyme hydrolyses specific substrate (BANA) release
cromophore ( B-naphtalamide) Cromophore changes color
on addition of a substance( fast garnet)
Perioscan is a popular diagnostic kit uses BANA reaction.
May be positive in clinically healthy site
Cannot detect disease activity
Limited organisms detected
Other pathogens may be present if it’s negative.
Molecular Biology Techniques
• Basic Principle: Analysis of DNA, RNA and protein structure.
Hybridization: Pairing of complimentary strands of DNA to
produce a double stranded DNA
Nucleic acid probe: is a known DNA/RNA which is synthesized
artificially and labeled with a enzyme or a radioisotope for
detection when placed in a plaque sample
DNA Probe: uses a segment of a
single stranded DNA, labeled
with a enzyme of a radio
isotope, that is able to hybridize
to a complimentary nuclei
strand, and thus detect presence
of target microorganism.
Whole genomic: Targets the whole DNA strand rather then a
specific sequence or gene.
High chances to cross react with non target microorganism
Lower sensitivity and specificity.
Oligonucleotide probes: target
variable region of 16sRNA
or a specific sequence in the
Higher sensitivity and
• Checkerboard DNA-DNA Hybridization Technology:
Developed by Socransky et.al.
40 bacterial species can be detected using whole genomic
digoxigenin-labeled DNA probes.
Large number of samples can be tested and upto 40 oral species
detected with a single test.
Advantages of DNA probes as compared to bacterial
1. More sensitive and specific
2. Requires as less as 104 cells of each species to be
3. Multiple species detected with a single test
4. Does not require viable bacteria
5. Large number of samples can be assessed.
2. Expert personnel to carry out the test
3. Not easily available
• Polymerase Chain Reaction (PCR):
Involves amplification of a region of DNA by a primer specific to
the target species.
If there is amplification then it indicates the presence of the target
species in the sample.
1. High detection limit. As less as 5- 10 cells can be
amplified and detected.
2. Less cross reactivity under optimal conditions
3. Many species can be detected simultaneously
1. Small quantity needed for reaction may not contain the
necessary target DNA
2. Plaque may contain enzymes which may inhibit these
Advances in characterizing the host response
• Diagnostic tests have been developed that add measures of the
inflammatory process to conventional clinical measures.
• These diagnostic tests gives information about
pattern of destruction
current activity of disease
rate of disease progression
extent & severity of further breakdown
response to therapy
• So, knowing about disease destructive process-
clinician can individualise their therapeutic approach,
and customize the treatment.
• Source of samples may be; GCF, Saliva, or Blood.
• GCF is most commonly used, where as saliva is recently been
• Assessment of Host response
i. Inflammatory mediators and products
ii. Host derived enzymes
iii. Tissue breakdown products
Inflammatory mediators & products:
• Cytokines- potent local mediators of inflammation
produced by variety of cells
• GCF- TNF α
• Good correlation with disease status and severity but not
• In untreated periodontitis- concentration of PGE2 increased
during active phase of periodontal destruction.
• Cytokines ∞ disease severity & status
• PGE2 ∞ active phase of periodontal disease
Host derived enzymes:
• Matrix components are dissolved by either
a. ECM metalloproteinase dependent
b. Plasmin dependent cleavage reactions
• Proteases and enzymes involved in these processes may be
used as diagnostic aids.
For periodontal diagnosis, the ideal diagnostic test should be
• Highly sensitive method capable of analyzing a single
periodontal site in health as well as disease.
• Highly specific.
• Simple to perform.
• A rapid, one or two stage procedure.
• Versatile in terms of sample handling, storage and transport.
• Amendable to chairside use.
• Economical. ( Chapple 1997)
Chairside periodontal test kits can be categorized as
• Microbiologic tests
• Biochemical test kits
• Genetic kits
Microbiological test kits
The bacteriological tests
(Microscopy, Culture, Omnigene, Affirm DP and Evalusite) are
mainly aimed at spirochetes, Aa, Pg and Pi.
Microbial tests can also be used to monitor periodontal therapy
directed towards the suppression or eradication of
• DNA probe systems
• available for the detection of A. actinomycetemcomitans, P.
gingivalis, P. intermedia, F. nucleatum, C. rectus, T. denticola
and E. corrodens.
• Evalusite is a kit that employs a novel membrane-based
enzyme immunoassay for the detection of three putative
periodontopathogens: Aa, Pg and Pi.
• a pink spot is displayed if the test organism is present.
• The main weaknesses of this test kit reside in
• 1) the assumption that the three detected organisms are
• (2) it is a multistage test;
• (3) it has a subjective calorimetric end point and (4) there is no
permanent record of the results.
• Perioscan is a diagnostic test kit that utilizes the BANA (N-
• developed to detect bacterial trypsin-like proteases in the
Biochemical test kits
• Perio 2000- to evaluate VSCs
• Prognos- Stik- to detect elevated levels of MMPs
• Perio- Check- to measure neutral protease activity
• PerioGard- to detect AST
• Pocket Watch- simple method for AST
Genetic test kits
• Various gene polymorphisms are considered to be risk factors
for the initiation or progression of periodontal disease.
• In 1997, Kornman et al. found an association between the
polymorphism in the genes encoding for interleukin-1α and
interleukin-1β and increased severity of periodontitis.
• PST® genetic susceptibility test - the first and only genetic
test that analyzes two interleukins (IL-1α and IL-1β) genes for
variations. IL-1 genetic susceptibility may not initiate or cause
the disease but rather may lead to earlier or more severe
• OralDNA® Labs has developed a salivary test, the
MyPerioID® PST®, that identifies a patient’s genetic
susceptibility and inherent risk to periodontal disease by
evaluating their interleukin-1 (IL-1) gene cluster,
• MyPerioPath®, that identifies the type and concentration of
13 pathogenic bacteria known to cause periodontal disease.
• In periodontology, the success of any treatment is dependent
upon the accuracy of the initial diagnosis.
• At present, the majority of chronic periodontitis cases can be
adequately managed using existing diagnostic methodology,
although it is clearly more desirable to be able to diagnose
“active disease” as it occurs, rather than months later.
• However, the clinician must ensure that the use of such tests
will benefit the patients in terms of both the value of
diagnostic data obtained and the cost in time and money.
• Carranza’s Clinical Periodontology 10th and 11th edition.
• Armitage GC, Jeffcoat MK, Chadwick DE: longitudinal
evaluation of elastase as a marker for the progression of
Periodontitis, J Periodontol 1994; 65:120.
• Beck JD: Issues in assessment of diagnostic tests and risk for
Periodontal diseases, Periodontol 2000;7:100