Methods of sampling

Methods of sampling
As mentioned earlier, the correlation between salivary MS counts and the number of MS-colonized tooth surfaces is relatively good (Lindquist et al, 1989), and simple salivary sampling methods are a more convenient and realistic means of assessing the severity of MS infection than sampling from individual tooth surfaces.
Laboratory methods. Saliva is collected, mixed with a proper transport medium, and forwarded to a microbiologic laboratory. After incubation using a selective medium, mutans colonies are counted and the results are expressed as the number of colonyforming units per milliliter of saliva.
Several selective media are available, and their properties are not identical: This fact must be taken into consideration in assessing the results. A common type of selective medium for plating mutans streptococci is the mitis-salivarius-bacitracin agar (Gold et al, 1973). With the exception of the rare serotype a, all types of mutans streptococci grow on this medium. Bacitracin is the main selective ingredient. Because the plates have a shelf life of only about 1 week, they are not convenient for chairside tests. 
For screening surveys using agar plates, the following simplified method has been described, eliminating the need for transportation, dilution, and plating of saliva (Kohler and Bratthall, 1979; Newbrun et al, 1984): Wooden spatulas are contaminated with saliva and immediately pressed against selective agar plates. After incubation, the number of colonies on a predetermined area of the plate is calculated. 
Chairside method. The so-called Strip Mutans test, described by Jensen and Bratthall (1989), is based on the ability of mutans streptococci to grow on hard surfaces and the use of a selective broth (high sucrose concentration in combination with bacitracin). Because the bacitracin can be added to the broth just before use, the shelf life of the test can be prolonged considerably compared to that of agar plates. 
The test set is used as follows: A bacitracin disc is taken from the vial with forceps or a needle. The cap is reclosed tightly. The bacitracin disc is put in the culture broth vial and allowed to stand for at least 15 minutes. The vial is shaken gently after 15 minutes. When more than one Strip Mutans test is to be run, the bacitracin discs can be added to the vials beforehand. However, only one Strip Mutans test can be performed in each vial, and vials to which bacitracin has been added must be used on the same day.
The patient is given a Dentocult paraffin pellet and instructed to chew it for 1 minute. 
The stimulated saliva should be swallowed or spat out.
A test strip is removed from the Strip Mutans container, so that only the square end is touched. About two-thirds of the strip is placed in the patient’s mouth and rotated on the surface of the tongue about 10 times. The strip is removed from the mouth, pulled between the patient’s closed lips to remove any excess saliva. The strip is placed in the culture vial containing the well-mixed bacitracin-broth solution. The cap is reclosed tightly (Fig 35). The patient data is written on the label, and the label is attached to the vial. The strip is incubated for 2 days at 35°C to 37°C (95°F to 99°F). The strip is removed from the culture vial and allowed to air dry. The treated side, which is marked with a line, can be examined immediately or later (Fig 36). After it is dried, the test strip can be stored for future reference in a plastic bag, plastic wrap,
autoclave plastic, or other similar material.
The bacitracin and the higher sugar content inhibit the growth of practically all microorganisms, other than S mutans, that grow in mitis-salivarius medium. In proportion to their actual amount in saliva, S mutans in the specimen will adhere to the treated side of the strip, and grow as small, dark or light blue colonies, 1 mm in diameter, or considerably less, when growth is very dense. The amount of S mutans per milliliter of saliva is estimated by comparing the colony density on the strip with the standard charts included in the instructions.
If the number of S mutans is very high, the treated side of the test strip will turn blue, and separate colonies will be indistinguishable. A test strip without S mutans may have a blue shade as a result of precipitation of the color indicator present in the culture medium. A magnifying glass or a microscope should be used to verify questionable cases.
The Strip Mutans method should not be used within 12 hours of an antibacterial mouthwash (eg, chlorhexidine) or 2 weeks of a course of antibiotics to avoid falsenegative results.
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Nancy, that’s a good article. I’ve been a big proennpot of xylitol for a couple of years. It’s been used since the 1960’s and now is being used in nursing homes as a mint or a dissolvable patch that can help seniors who suffer from dry mouth due to ailments, meds etc it’s been a blessing for those with this problem. Dry mouth (xerostomia) is a horrible condition as it causes many problems in the mouth, from severe decay to advanced periodontal disease. Thanks for bringing this up .by the way, gum sweetened just with xylitol is available on the internet as many commercial gum has other sweeteners added.

Mohan: Thank you! Finger brushing iiitnally seems so old fashioned. Especially after being constantly conditioned to switch to a better and more modern method ! After being plagued with the many dental problems I discussed in the article, I am mercifully dentist and ache free these days.Of course, as a bonus, you could give yourself an extra pat on the back for being environmentally friendly everytime you use your finger to brush, given that toothbrushes are an environmental nightmare.Interesting point you bring up with Vicco when Srini and I turned vegan we too switched to Vicco toothpaste. I was sad to find SLS in their toothpaste, which is incidentally not there in their export version. According to me SLS is both toxic and not vegan as every single chemical ingredient used in cosmetics have been at some point tested on animals. I did not try their toothpowder, though. I switched directly out of a brush+Vicco toothpaste to my own toothpowder. I have tried Kottakal Arya Vaidya sala’s toothpowder and Namboodri’s toothpowder, but as I had mentioned in the comments, I found my own toothpowder far superior to both of these.

You’re on top of the game. Thanks for shaginr.

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Hello! Am i glad that i came across this altcire. Thank you so much. Had a couple of questions1. Your opinion on himalaya dental cream and their non-alcoholic mouthwash?2. I use an extra soft toothbrush. That is not good as well?3. I do have fillings as a part of horrible diet during my very short stay abroad. Came back, got roundly scolded by dentist who asked me if i could read/write. Changed my oral regime -never ever touched crapacola/soda and touch wood ever since i haven’t even had cleaning to be done. That’s what a different dentist told when i had visited him, after 4 yrs, for cleaning. My question is does oil pulling affect/ worst case pull out’ the fillings? Really, wouldn’t want to make a trip to the chair.4. Is the massage of the gums also to be done w/ the powder?5. What is soap nut? Any idea where we get it in bangalore/bombay?6. Do you sell’ this powder so that lazy oafs, like mme, can just buy it ?Thanks

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Articles for theme “caries”:
Cariogenicity of mutans streptococciMutans streptococci are acidogenic as well as aciduric and can adhere to tooth surfaces (Gibbons et al, 1986). Mutans streptococci can produce extracellular and intracellular polysaccharides from sucrose. Intracellular polysaccharides in particular can be degraded during periods of low nutrient supply, indicating that these polysaccharides increase the virulence of some MS species (S mutans and S sobrinus).  Because the microbial ecology of the mouth is highly complex, strains of the same species could vary considerably in virulence (Bowden and Edwardsson, 1994).
Role of Specific Cariogenic MicrofloraIntroductionMicroorganisms implicated in the etiology of dental caries must be acidogenic as well as aciduric. To initiate carious lesions in enamel, the microorganisms must also be able to colonize the tooth surface and survive in competition with less harmful species, forming biofilms¾the so-called dental plaque. As early as 1960, Fitzgerald and Keyes showed that certain microorganisms isolated from human dental plaque, when inoculated in germ-free rodents on a high-sucrose diet, resulted in the spread of rampant caries.
Strategies for prevention and control of caries based on plaque ecology hypothesis According to the plaque ecology hypothesis, low pH (less than 5) will promote overgrowth of aciduric microorganisms, such as the cariogenic mutans streptococci and lactobacilli, at the expense of less acid-tolerant plaque microorganisms, such as S oralis, which are associated with healthy tooth surfaces.  Therefore the treatment strategy would be to increase plaque pH and thereby promote reestablishment of the harmless normal microflora of the tooth surfaces.
Effect of plaque ecologyOwing to differences in local environmental conditions, the microflora of mucosal surfaces differs in composition from that of dental plaque. Similarly, the plaque microflora varies in composition at distinct anatomic sites on the tooth ¾ for example, in fissures, on approximal surfaces, and in the gingival crevice. The resident microflora of a site acts as part of the host defenses by preventing colonization by exogenous (and often pathogenic) microorganisms.
Colonization of microenvironmentsThe oral cavity consists of several major and minor compartments, each constituting a separate microenvironment not easily affected by major events in the oral cavity. Examples of major compartments are the tongue, the oral mucosa, and the tonsils. The different approximal tooth surfaces, occlusal fissures, and gingival sulci are regarded as minor compartments. A specific area that supports a bacterial flora is termed a habitat. The flora of a habitat develops through a series of stages, collectively called colonization.