1. Advanced Diagnostic Aids
in Dentistry

2. Contents Introduction
Limitations of conventional periodontal diagnosis
Advances In Clinical Diagnosis
Advances In Radiographic Assessment
Advances Microbiologic Analysis
Advances In Characterizing The Host Response

3. Introduction
Definition : Diagnosis is defined as identifying the disease from an evaluation of history, signs and symptoms, laboratory tests and procedures.
Importance :
It identifies and indicates the nature of etiological factors
Indicates the nature of pathological processes
It is essential for treatment planning

4. types of diagnosis Provisional differential comprehensive therapeutic
emergency
Diagnostic aids in periodontics conventional
advanced

5. Periodontal disease Gingival Inflammation
Periodontal Destruction
Diagnosis :- clinical evaluation ( Gingivitis)
clinical evaluation
(periodontitis)
tissue destruction

6. Tissue destruction ( Periodontitis)
Loss of connective tissue
clinical radiographic
attatchment loss bone loss
Gives historical evidence of damage
Identify and quantify current clinical signs of inflammation

7. Limitations Does not provide cause of condition
Susceptibility of patient
Cannot reliably identify sites with ongoing periodontal destruction
Cannot differentiate whether response to therapy is positive or negative

8. Periodontal disease is localised and multifactorial.

9. Consideration should be given microbiologic
immunologic
systemic
genetic
behavioural factors
in addition to clinical and radiographic parameters.

10. The focus is now disease prevention, early discovery, and intervention to minimize treatment, thus enabling the most desirable outcomes.
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 diagnostic process.

11. Classification Aids used in clinical diagnosis
Conventional probes – regular examination
Millimeter probes – for gingival bleeding
Pressure sensitive probes
Other clinical diagnostic aids
Filter papers- for measuring GCF
Periotron for measuring GCF
Olfactometer- for mouth odors
Mobilometer- for tooth mobility
PSR- for faster screening and recording of PD

12. Aids used in radiographic diagnosis
IOPA radiographs
Ortho-pantomograph
Xero-radiography
Aids used in microbial diagnosis
Direct examination
Light microscopy
Dark field microscopy
Culture tests
Aerobic culture
Anaerobic culture

13. Aids used in immunological diagnosis
Immunofluorescense- direct and indirect
Polymerase chain reaction
Latex agglutination
Flow cytometry
ELISA
Biochemical diagnosis
Studies for prostaglandins
Studies for collagenase
Other diagnostic aids
i. study casts
ii. FSEIA
iii. N-benzoyl-DL- arginine 2- naphthylamide (BANA)

14. Advanced diagnostic aids
Advanced periodontal probes
Automated controlled force probes
Thermal periodontal probes
Advanced diagnostic aids in periodontal radiography
Digital radiography
Substraction radiography
Digital substraction radiography
Transmission radiography
Magnetic resonance imaging
Computerized tomography
Nuclear medicine bone scan

15. Advanced diagnostic aids in microbiologic analysis
Advances in culturing technique
Advances in immunodiagnostic methods
Advances in enzymatic methods
Advances in nuclear biology- PCR and DNA probes
Advanced diagnostic aids in charting the host response
Assessment of inflammatory mediators and products
Assessment of tissue breakdown products
Assessment of host derived enzymes

16. Advanced diagnostic aids to determine periodontal disease activity
Crevicular contents
Products of bacteria
Products of host cells and host immunity
Markers in peripheral blood
Neutrophil functional profile
Monocyte responsiveness to LPS
Circulating antibodies to plaque bacteria
Detection of specific periodontal pocket bacteria
a. DNA probes
b. BANA hydrolysis
c. Antibody techniques

17. Advances in clinical diagnosis
Degree of gingival inflammation
a. redness and swelling
b. gingival bleeding
Gingival bleeding ∞ plaque accumulation
gingival inflammation
(Greenstein G et al 1981)
size of inflammatory infiltrate
probability of losing attatchments
(Lang et al.1991)

18. Gingival temperature
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

19. Elevated subgingival temperature ∞ attatchment loss
& elevated propertions of
periodontopathic bacteria
( Haffajee et al.)

20. Periodontal probes Most widely used
Clinical assessment of connective tissue destruction in periodontitis
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

21. CAL is a more objective measure of loss of Existing periodontal support.
CAL also does not give any indication of current disease activity.
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 tissues.

22. Classification of periodontal probes depending on generation.
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
collection.
eg: Williams periodontal probe
CPITN probe
UNC-15 probe
University of Michigan’O’ probe
Goldman Fox probe
Glickman probe
Merritt A and B probe

23. 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
Florida probe
Interprobe, Foster Miller probe.

24. 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 probes.
If the fourth generation can be made, it will aim in
addition to identify the attachment level without
penetrating it.
e.g.: Ultra sonographic probe.

25. Florida probe:
Tip is 0.4mm
Sleeve- edge provides reference
to make measurements
Coil Spring; provides constant probing force
Computer for data storage.

27. Disadvantages of Florida probe.
Lack of tactile sensitivity
Fixed probing force
Underestimation of deep periodontal pockets.
Other electronic probes:
Improvised Florida PASHA probe
Interprobe
Perioprobe
Foster Miller probe
Toronto Automated ( difficult to reproduce patient head position and in 2nd and 3rd Molar area.)

28. PSR system
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.

29. 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 and charting

30. 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.

31. Digital Radiography Computerized images.
Image property almost equal to conventional radiographs
1/3rd to half reductions in radiation dose.

32. Substraction Radiography
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)

33. Perfect accuracy at a lesion depth of 0.49 mm
( Grondhal et al 1988)
Limitations: needs paralleling technique and accurate superimposition.

34. 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

35. Computer Assisted Densitometric Image Analysis (CADIA)
Video cameras measures light transmitted through Radiographs signals from camera converted into gray scale images camera interfaced with image processor + computer

36. Offers objective method for following alveolar bone density changes quantitatively over time.
Higher sensitivity
High degree of reproducibility
accuracy

37. COMPUTED TOMOGRAPHY
Computed Tomography scanning is widely used in the evaluation of the implant patient

38. A thin fan beam of X-Rays rotates around the patient to generate in one resolution a thin axial slice of the area of interest.
Multiple overlapping axial slices are obtained by several revolution of the X-ray beam until the whole area of interest is covered.
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 patient.

39. 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 INCLUDE:-
1. AXIAL
2. PANORAMIC
3. CROSS-SECTIONAL. Views of the Jaws.

41. ADVANTAGES of Computed Tomography
1. True cross sections offer a precise and detailed evaluation of the height and width of the ALVEOLAR RIDGE.
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.
1. Superioinferior
2. Anteroposterior
3. Buccolingual

42. 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.

43. 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 planning.
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.

44. CONE-BEAM COMPUTED TOMOGRAPHY
Cone-Beam Computed Tomography (CBCT) is a new imaging modality that offers significant advantages for the evaluation of implant patients.

45. 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 structures.
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.

46. Advances in Microbiologic Analysis
Strong evidence for actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Tannerella forsythia (Tf).
Other organisms that are thought to have etiologic role are Camphylobacter rectus, Eubaterium nodatum, Fusobacterium nucleatum, Peptostreptococcus micros, Prevetolla intermedia and Prevetolla nigrescens, Trepenoma Denticola

47. Microbiologic tests( that can identify)
Can support diagnosis of various Periodontal disease.
Can tell about initiation & progression
Active & Inactive
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

48. Bacterial culturing
Direct microscopy
Immunodiagnostic methods
Enzymatic methods
Diagnostic assays based on molecular biologic techniques

49. Bacterial culturing
Historically, widely used in characterizing composition of subgingival microflora.
Plaque sample anaerobic culture
selective non-selective
Advantage: clinician can obtain absolute or relative count
2. invitro method for antibiotic susceptibility

50. Limitations :
Culture can grow only live bacteria.
Sensitivity is low
Requires sophisticated equipment and experienced personnel.
Time consuming
expensive

51. Direct microscopy 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.

52. Immunodiagnostic methods
It employs Antibody
that recognize
specific bacterial antigen
Various procedures:
Direct & indirect immunofluorescence assays
Flow cytometry
ELISA
Membrane assay
Latex agglutination

53. Immunofluorescence assay
Direct IFA: AB conjugated with Fluorescein marker + Bacteria ( Antigen) = Immuno complex
Indirect IFA: Primary AB + Bacteria= Immune Complex+ Secondary Fl conjugated AB

54. Indirect IFA
Direct IFA

55. 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

56. merits : rapid identification
labels bacterial cells species specific antibody
fluorescin conjugated secondary
antibody
Demerits:
sophistication
expensive

57. 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.

59. Specific antigen bind to the antibody + Secondary antibody added.
 Well with precoated antibody + Sample to be tested= immune complex
Specific antigen bind to the antibody + Secondary antibody added.
Immunofloresence dye bound to secondary antibody
 Substrate added which changes the color of the solution
Amount of florescence checked by photometer (450nm)

60. 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 positive.
Advantages:
Simple and Rapid testing
Higher sensitivity and specificity.

61. Enzymatic methods
Bacteria release specific enzymes. Certain group of species share common enzymatic profile.
e.g. Tf, PG, Td, and Capnocytophaga species release trypsin like enzyme.
Enyme hydrolyses specific substrate (BANA) release cromophore ( B-naphtalamide) Cromophore changes color on addition of a substance( fast garnet)

62. Perioscan is a popular diagnostic kit uses BANA reaction.
Disadvantage:
May be positive in clinically healthy site
Cannot detect disease activity
Limited organisms detected
Other pathogens may be present if it’s negative.

63. 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

64. 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.

65. DNA Probe
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.

66. Oligonucleotide probes: target variable region of 16sRNA or a specific sequence in the DNA strand.
Higher sensitivity and specificity.

67. 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.

68. Advantages of DNA probes as compared to bacterial culturing.
More sensitive and specific
Requires as less as 104 cells of each species to be detected.
Multiple species detected with a single test
Does not require viable bacteria
Large number of samples can be assessed.
Disadvantage:
Expensive
Expert personnel to carry out the test
Not easily available

69. 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.

70. Advantages:
High detection limit. As less as cells can be amplified and detected.
Less cross reactivity under optimal conditions
Many species can be detected simultaneously
Disadvantage:
Small quantity needed for reaction may not contain the necessary target DNA
Plaque may contain enzymes which may inhibit these reactions.

71. 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

72. 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 researched.
Assessment of Host response
Inflammatory mediators and products
Host derived enzymes
Tissue breakdown products

73. Inflammatory mediators & products:
Cytokines- potent local mediators of inflammation
produced by variety of cells
GCF TNF α
IL-1
IL-6
IL-8
Good correlation with disease status and severity but not disease progression

74. In untreated periodontitis- concentration of PGE2 increased during active phase of periodontal destruction.
Cytokines ∞ disease severity & status
PGE ∞ active phase of periodontal disease

75. Host derived enzymes: Matrix components are dissolved by either
ECM metalloproteinase dependent
Plasmin dependent cleavage reactions
Proteases and enzymes involved in these processes may be used as diagnostic aids.

76. Aspartate aminotransferases
Collagenase
β-glucuronidase
Lactate dehydrogenase
Arylsulfatase
Elastase
Alkaline phosphatase

77. Tissue Breakdown Products
Hydroxyproline
Glycosaminoglycans

78. For periodontal diagnosis, the ideal diagnostic test should be
Quantitative.
Highly sensitive method capable of analyzing a single periodontal site in health as well as disease.
Reproducible.
Highly specific.
Simple to perform.
A rapid, one or two stage procedure.
Non-invasive.
Versatile in terms of sample handling, storage and transport.
Amendable to chairside use.
Economical ( Chapple 1997)

79. 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 periodontopathogenic  microorganisms

80. Omnigene DNA probe systems
available for the detection of A. actinomycetemcomitans, P. gingivalis, P. intermedia, F. nucleatum, C. rectus, T. denticola and E. corrodens.

81. Evalusite
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 causing disease;
(2) it is a multistage test;
(3) it has a subjective calorimetric end point and (4) there is no permanent record of the results.

82. PerioScan®
Perioscan is a diagnostic test kit that utilizes the BANA (N-benzoyl-DL-arginine-2-naphthylamide)-hydrolysis reaction,
developed to detect bacterial trypsin-like proteases in the dental plaque

83. 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

84. 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 disease

85. Salivary diagnostics
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.

86. Conclusion
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. 

87. References 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

88. Thank you