**5. Collection of specimen from cervical lymph nodes**

The cervical and supraclavicular lymph nodes of the neck are in the drainage path of many infectious and malignant diseases; an examination should be made by FNAC. FNAC of cervical lymph nodes is a well-accepted diagnostic test of choice in both adult and pediatric patients for reliably distinguishing between benign/ reactive and malignant processes and guiding patient management with simple observation or antimicrobial therapy for infections, chemotherapy and radiation therapy or the need for more sample tissue like core biopsies or excisional biopsy of the lymph node itself [5].

Thus FNAC is recommended as a safe, quick and inexpensive tool in the diagnosis of head and neck lesions.

#### **5.1 Saliva**

Collection of human saliva offers a noninvasive method for monitoring the disposition of unbound (free) drugs and many endogenous biomarkers. Human genomic DNA extracted from buccal epithelial cells and white blood cells found in saliva can be used in various applications in diagnostics. The correlations between blood and saliva biomolecule/biomarker concentrations range from good to excellent. Methods of collecting saliva range from simply spitting into a collection cup or using absorbent pads or swabs or the trademarked collecting devices. Freeze-thaw techniques are often employed to help break up the mucin protein that is responsible for the sticky, foamy saliva. There are few inherent drawbacks for using saliva as an ideal biofluid. In some cases, the drug, metabolites or other compounds being assayed may bind to absorbent materials, thus reducing recovery or giving a misleading result [6].

*Saliva is useful for testing:*


#### **5.2 Collection of specimens**

Whole saliva is commonly collected by draining, spitting, suction, and swab or absorbent method. Common stimuli used are chewing on paraffin wax and chewing gum at a fixed rate. As described by Wong D, the proposal for standardized collection of whole and glandular saliva can be followed for saliva sample collection.


Collection of saliva into ice-cooled vials is recommended to slow down the activity of hydrolytic enzymes present in saliva in air-cooled preset environment. Proprietary collection vials contain a cocktail of protease inhibitors and

**53**

*Methods of Collection and Transport of Materials to Laboratory from Oral and Dental Tissue…*

bacteriostatic chemicals. Bacteria and cellular debris have to be removed directly after collection by centrifugating for 5 min at 10,000 g, or 20 min at 3000 g or by

After collection, salivary samples must be snapped frozen in liquid nitrogen. In the absence of liquid nitrogen, freezing in dry ice is a practical choice when samples are collected. For a prolonged storage, −80°C temperature is preferred over storage at−20°C. The salivary samples can be diluted with glycerol (1:1) before storage. For immunochemical analysis such as ELISA, the saliva can be stored frozen after dilution (e.g., 1:100) in the assay buffer, usually PBS—0.5% Tween-20. To maintain the integrity of the proteins, before testing, the deep-frozen samples must be thawed as

and HCO4

best analyzed in fresh saliva samples. Storage of salivary DNA and RNA is similar to

**Rationale:** The idea of culturing microorganisms is not new or foreign to the practice of dentistry. There are situations in dentistry where it is not only important to know whether microorganisms are present in a lesion but also the type of microorganism. It follows from this that to best treat these infections the dentist needs to know what antibiotic would be most effective against the particular organism. Thus the culture and sensitivity test for bacterial organism is indispensable [7]. The biggest challenge today will be the transition from culture-based microbiological

a.The success of oral bacteriologic/fungal identification procedures depends to a

b.Lack of care and faulty methods of collection and handling of the specimen

c.Because most of the microorganisms encountered in dental or head and neck infections are caused by facultative anaerobic or obligate anaerobic bacteria,

a.The biopsy for culture is similar to the surgical biopsy for tissue diagnosis. A 5 × 5 × 5-mm piece of tissue is excised from the lesion with aseptic technique (here, it is undesirable to biopsy the normal tissue border, as there will not be

b.The biopsy specimen is placed in a sterile test tube containing sterile physiologic saline as the transport media (formalin is not used). The cap is secured and the specimen sent to the laboratory, along with the completed history sheet

great extent on the manner in which the specimen is collected.

the laboratory may prefer the use of a reducing transport media.

make the laboratory procedures valueless.

any organisms in the normal tissues).

<sup>−</sup>) and viscoelastic properties is

non-cotton-based filtration or vortexing (2 min, maximal speed).

*DOI: http://dx.doi.org/10.5772/intechopen.92677*

quickly as possible. Analysis of pH (H+

that of a salivary protein sample [6].

**7. Culture and sensitivity tests**

testing to molecular-based testing.

**7.2 Tissue specimen for culture**

request form.

**7.1 Collection of specimen**

**6. Storage and transport**

*Methods of Collection and Transport of Materials to Laboratory from Oral and Dental Tissue… DOI: http://dx.doi.org/10.5772/intechopen.92677*

bacteriostatic chemicals. Bacteria and cellular debris have to be removed directly after collection by centrifugating for 5 min at 10,000 g, or 20 min at 3000 g or by non-cotton-based filtration or vortexing (2 min, maximal speed).
