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The composition, function and role of saliva in maintaining oral health: A review


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Abstract Saliva is certainly one of the most important components in the oral environment and an integral component to oral health. The components of saliva, its functions in maintaining oral health and the main factors that cause alterations in salivary secretion will be reviewed, the importance of saliva in caries development and bacterial plaque formation will be discussed, and its role as an aid to diagnosing certain pathologies will also be discussed here. Saliva aids in maintaining mucosal integrity and in digestion through salivary enzymes. Saliva is essential information of the pellicle, which protects the tooth after eruption. Saliva has several oral benefits including buffering, remineralization, and lubrication. Consider the acid attack on the teeth after a cariogenic episode, saliva aids in mechanically removing food debris and bacteria from the oral cavity and teeth, reduced salivary flow causes ill effects to the oral tissues. Keywords: Caries, dental plaque, saliva, salivary flow rate, salivary proteins, xerostomia
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International Journal of Contemporary Dental and Medical Reviews (2017), Article ID 011217, 6 Pages
The composition, function and role of saliva in maintaining
oral health: A review
Brij Kumar1, Nilotpol Kashyap1, Alok Avinash1, Ramakrishna Chevvuri2, Mylavarapu Krishna Sagar3, Kumar Shrikant3
¹Department of Pedodontics and Preventive Dentistry, Rungta College of Dental Sciences and Research, Bhilai, Chhattisgarh, India, ²Department of Public
Health Dentistry, Rungta College of Dental Sciences and Research, Bhilai, Chhattisgarh, India, ³Department of Pedodontics and Preventive Dentistry, People’s
Dental Academy, Bhopal, Madhya Pradesh, India
Saliva is certainly one of the most important components in the oral environment and an
integral component to oral health. The components of saliva, its functions in maintaining
oral health and the main factors that cause alterations in salivary secretion will be
reviewed, the importance of saliva in caries development and bacterial plaque formation
will be discussed, and its role as an aid to diagnosing certain pathologies will also be
discussed here. Saliva aids in maintaining mucosal integrity and in digestion through
salivary enzymes. Saliva is essential information of the pellicle, which protects the tooth
after eruption. Saliva has several oral benets including buering, remineralization, and
lubrication. Consider the acid attack on the teeth after a cariogenic episode, saliva aids in
mechanically removing food debris and bacteria from the oral cavity and teeth, reduced
salivary ow causes ill eects to the oral tissues.
Keywords: Caries, dental plaque, saliva, salivary ow rate, salivary proteins, xerostomia
A critical component of the oral environment is saliva, a dilute
aqueous solution containing both inorganic and organic
constituents. Saliva plays an essential role during mastication,
in swallowing and in speech. The substances dissolved in saliva
during mastication are transported to stimulate taste receptors
for taste perception.
The salivary amylase is a digestive enzyme responsible for
the initial stage in starch and glycogen breakdown, and salivary
lipase secreted by lingual salivary glands (Von Ebner’s glands)
may play a signicant role in fat digestion. In many animals
evaporation of saliva spread on fur or while panting is important
in temperature regulation during heat stress.[1]
The functions of saliva are to protect the oral tissues by
keeping them moist and by providing a lubricating mucoid
secretion, by maintaining a uid environment with high calcium
and phosphate concentrations and the power of buering acids
and to initiate the digestion of starch. Impaired salivary secretion
(hyposalivation) increases the risk of oral diseases such as dental
caries and oral candidal infection.[2]
Recently, additional functions of salivary glands have been
uncovered. Salivary glands have been shown to contain, and possibly
secrete, a large number of physiologically active substances, such as
nerve growth factor, vasoactive peptides, and regulatory peptides.
Thus salivary glands may have a role in functions not normally
associated with that traditional alimentary function.[3,4]
Composition of Saliva [Table1][5]
Functions of saliva in humans
Digestive functions
Although amylase is a major component of the parotid secretion
and is present at an appreciable level in the submandibular uid
as well, its salivary role in the digestion of carbohydrates is really
minimal. The only eective conversion of starch to maltose that
occurs in the oral cavity is in food-retentive sites, and this benets
primarily the plaque bacteria. Most of the food is swallowed
rather quickly, and in the stomach salivary amylase would be
minimally eective, given the low pH and high proteolytic
activity of the gastric juice.[6]
Dr.Brij Kumar, Department of Pedodontics
and Preventive Dentistry, Rungta College
of Dental Sciences and Research, Bhilai,
Chhattisgarh, India. Phone: +91-8827800994.
Received: 30October 17
Accepted: 15 December 17
doi: 10.15713/ins.ijcdmr.121
How to cite this article:
Brij Kumar, Nilotpol Kashyap, Alok Avinash,
Ramakrishna Chevvuri, Mylavarapu Krishna
Sagar, Kumar Shrikant, “The composition,
function and role of saliva in maintaining oral
health: Areview, Int J Contemp Dent Med
Rev, vol.2017, Article ID: 011217, 2017.
doi: 10.15713/ins.ijcdmr.121
Kumar, et al. e composition, function, and role of saliva in maintaining oral health
The high water content of the parotid secretions
moistening the food and the mucins generated by the
submandibular, sublingual, and minor salivary glands coating
the food combine eectively to facilitate ingestion. Other
lubrication molecules, such as the parotid proline-rich
glycoprotein albumin complex, may also participate in the rate
of food passage by becoming incorporated into pellicle, thus
providing a lubricating interface between teeth and facilitating
Saliva also plays a gastronomic role by solubilizing many of
the food components and acting as a medium for interaction
with the receptors on the taste cell. It has been proposed that
a specic zinc-binding salivary protein, gustin, and mediates
taste sensation. Saliva also enhances taste perception by its
relatively low level of salts and its very low concentration of
sugar; thus, in a sense, it does not compete with exogenous
taste modalities.[7]
Protective Functions
Lubrication and demulcent properties
From an evolutionary point of view, the oldest function of
salivary glands is to supply lubrication molecules, to coat not
only the food but the oral soft tissue as well. The lubrication lm
allows for ready phonation as well as food passage and provides
for smooth tissue surfaces that exhibit minimal friction and are
comfortable as well as functional. The lubricating properties
of saliva have always been ascribed to the mucin glycoproteins
because they can provide uid layers with high lm strength,
and there are several experimental models to show that salivary
mucin and similar molecules do indeed have eective lubricating
properties. Very recently, Hatton et al. (1985) showed that the
proline-rich glycoprotein of parotid saliva, when complexed
with albumin, was also an extremely eective lubricant. The
distribution of this complex in the oral cavity remains to be
established, but it should be functional on teeth as part of
pellicle, and on mucous membranes as well. It could also be part
of the food coating but is probably overshadowed by the much
more adhesive mucin.
Maintenance of Mucous Membrane Integrity
The salivary mucins possess rheological properties which include
low solubility, high viscosity, elasticity, and adhesiveness, which
enable them to concentrate on the oral mucosal surface, where they
provide an eective barrier against desiccation and environmental
insults. The molecular structure of salivary mucins enables them
to bind water eectively, and hence their presence on the mucous
membrane surfaces serves as natural “waterproong” and helps to
maintain these tissues in a hydrated state.
Mucins have been shown to be important in the control of
permeability of mucosal surface, and the presence of a salivary
lm is important in limiting penetration of a variety of potential
irritants and toxins in foods and beverages as well as of potentially
hazardous agents from tobacco smoke and other sources.[8]
A variety of proteolytic enzymes is generated in the bacterial
plaque around the teeth and in the crevicular area, especially
in people with periodontitis. Proteases are also generated by
polymorphonuclear leukocytes, the numbers being related to the
level of inammatory disease. The bacterial and PMN proteases
(e.g., elastase, collagenase, and cathepsin) have the potential of
aecting the integrity of the mucous membranes and causing
ulceration. Mucins are protective in this regard since their
glycosylated regions are very resistant to proteolysis.
There is also a second line of defense against protease
activity, cysteine-containing phosphoproteins, in particularly
high concentration in submandibular saliva, which are identical
to Cystatin S. Cystatins S is an inhibitor of cysteine proteinases,
especially Cathepsin C. This antiprotease activity is augmented
by antileukoprotease, an eective inhibitor of granulocyte elastase
and Cathepsin G, present in both parotid and submandibular
glands, but to a much greater extent in the former.[9]
Table1: Composition of saliva:(mg/100 ml)
Whole(mixed) Resting Stimulated
Mean Range Mean Range
Total solids 500 300–800 530 400–900
Organic constituents
Proteins 220 140–640 280 170–420
Amino acids 4
Amylase 38
Lysozyme 22 11 0.4–62
IgA 19
IgG 1.4
Glucose 0.2
Citrate 1.0 1.0 0.5–3
Lactate Trace
Ammonia 3 1–12
Urea 20 12–70 13 0.6–30
Uric acid 1.5 0.5–3 3 1–21
Creatinine 0.1 0.05–0.2
Cholesterol 8 2.5–50
CAMP 7 50
Inorganic constituents
Sodium 15 0–20 60
Potassium 80 60–100 80
iocyanate‑smoker 9 6–12
Non‑smokers 2 1–3
Calcium 5.8 2.2–11.3 6
Phosphate(P) 16.8 6.1–71 12
Chloride 50 100
Fluoride(ppm) 0.028 0.015–0.045
e composition, function, and role of saliva in maintaining oral health Kumar, et al.
Soft Tissue Repair
Licking one’s wounds may be more than metaphor. The
presence of nerve growth factor and epidermal growth factor
in the submandibular saliva may accelerate wound-healing.
Epidermal growth factor is present in human saliva but at much
lower levels. The eect of saliva in oral wound-healing in humans
remains to be established.
An alternate role for saliva in wound-healing is suggested by
a paper of Volker (1942), in which he showed that saliva speeds
blood coagulation, both by aecting the anticoagulant valuable
property in an area where rough food or traumatic injury can
induce bleeding and bleed readily due to inammatory disease.[10]
Maintenance of Ecological Balance
Colonization of tissue surfaces, adherence is a critical event
for the survival of many bacteria, and interference with this
process, bacterial clearance, by mechanical, immunological, and
non-immunological means is one of the major functions of the
salivary defense mechanism. The ability of saliva to maintain an
appropriate ecological balance in the oral cavity is an important
evolutionary force in the long period of human existence before
plaque control.
Debridement and Lavage
The physical ow of saliva augmented by the muscular activity of
the lips and tongue eectively removes a large number of potentially
harmful bacteria from teeth and mucosal surfaces. This clearance
mechanism is similar to tearing and blinking in the eye, blowing the
nose, and coughing and expectorating to clear the lungs.[11]
In addition to physical eects, saliva can interfere with bacterial
adherence by more direct means that depend on molecular
interactions. The ability to inhibit bacterial attachment is a
major characteristic of the secretory IgA system and is the
rationale for the interest in an oral vaccine against caries. In
addition to these made to order antibodies, there is a variety of
ready-to- wear macromolecules, some very specic in action,
which mask bacterial adhesins or compete with them for
attachment sites on tissue. They may also function by clumping
or aggregating bacteria to the point where they can no longer
eectively adhere to hard or soft tissue and are expectorated
or swallowed. Most attention in experimental studies of
aggregation has been given to the high molecular weight
mucins. The presence of multiple complex oligosaccharide side
chains and a characteristic micro heterogeneity provide a wide
range of possibilities for interactions with many bacteria. The
amount of covalently bound lipid can also aect the properties
of mucins and can inuence their propensity for bacterial
Direct Antibacterial Properties
A group of salivary proteins lysozyme, lactoferrin, and
lactoperoxidase working in conjunction with other components
of saliva can have an immediate eect on oral bacteria, interfering
with their ability to multiply or killing them directly. Lysozyme
can cause lysis of bacterial cells, especially Streptococcus mutans
by interacting with anions of low charge density chaotropic ions
(thiocyanate, perchlorate, iodide, bromide, nitrate, chloride, and
uoride), and with bicarbonate. It has recently been shown that
another cationic peptide in saliva the histidine-rich peptide of
parotid saliva has growth-inhibitory and bactericidal eects on
oral bacteria. The histidine-rich peptides appear to be eective
antifungal agent as well, able to inhibit growth and kill Candida
albicans at very low concentration.[14]
Lactoferrin, the exocrine gland equivalent of transferrin, is
eective against bacteria that require iron for their metabolic
processes. It can compete with the bacterial iron-chelating
molecules, and deprive the bacteria of this essential element.
Lactoferrin is also capable of a bactericidal eect that is distinct
from simple iron deprivation.
Salivary peroxidase is part of an antibacterial system which
involves the oxidation of salivary thiocyanate by hydrogen
peroxide (generated by oral bacteria) to hypothiocyanite and
hypothiocyanous acid. These products, in turn, aect bacterial
metabolism (especially acid production) by oxidizing the
sulfhydryl groups of the enzymes involved in glycolysis and sugar
transport. The antimicrobial eect of salivary peroxidase against
S. mutans is signicantly enhanced by interaction with secretory
IgA. The protective potential of all the antibacterial proteins
can be extended by interaction with mucin which can serve to
concentrate this defense force at the interface of the mucosa and
the inhospitable external environment.
When teeth are present, especially if some gingivitis exists,
the oral uids will be augmented by a contribution from the
gingival crevice area, the gingival crevicular uid. This uid can
contribute to the oral defense system by providing: (a) Serum
antibodies against oral bacteria, especially IgG antibodies,
(b) phagocytic cells (PMN’s), and (c) antibacterial products
liberated from the phagocytic cells (e.g. lysozyme, lactoferrin,
and myeloperoxidase).[15]
Maintenance of pH
Saliva is eective in helping to maintain a relatively neutral pH
in the oral cavity, in the bacterial plaque, and on swallowing, in
the esophagus as well. In the oral cavity and the esophagus, the
major regulation of pH, especially during eating or drinking, is
the salivary bicarbonate, the level of which varies directly with
ow rate.
In the bacterial plaque, where acid production is the natural
sequela to bacterial metabolism of carbohydrates, saliva helps
regulate pH in several ways. Bicarbonate, phosphate, and
histidine-rich peptides act directly as buers once they have
Kumar, et al. e composition, function, and role of saliva in maintaining oral health
diused into the plaque. Urea from saliva is converted by bacterial
urease to ammonia, which can neutralize the acid. Amino acids
and peptides can be decarboxylated to form monoamines
and polyamines, a process which consumes hydrogen ions.
Arginine and arginine peptides can form ammonia as well as the
polyamine, putrescine, and thus can be particularly eective in
elevating plaque pH.
Maintenance of Tooth Integrity
In addition to helping to counter plaque acidity, saliva helps
protect the teeth in a number of other ways. This protective
function begins immediately after tooth eruption into the
oral cavity. Although the crown of the tooth is fully formed
morphologically when it erupts, it is crystallographically
incomplete. Interaction with saliva provides a post-eruptive
maturation through diusion of ions such as calcium, phosphorus,
magnesium, and uoride, as well as other trace components, into
the surface enamel. This maturation increases surface hardness,
decreases permeability, and has been experimentally shown to
increase resistance to caries.[16]
Once tooth begins to function in the mouth, its developmental
cuticle or pellicle is rapidly worn away and is replaced by a
constantly replenished salivary lm, the acquired pellicle. This
selectively adsorbed coating of proteins and lipids provides a
protective barrier and a lubricating lm against excessive wear,
a diusion barrier against acid penetration, and a limitation
against mineral egress.[17]
One of the major contributions of salivary research during
the past decade has been the characterization of the system
that regulate the ionic environment in the plaque and oral
cavity. A group of phosphoproteins acidic proline-rich proteins,
statherin, and cysteine-containing phosphoproteins provide
this protection by eectively binding calcium and helping to
maintain saliva in a state of supersaturation with respect to
calcium phosphate salts. They bind to the surfaces of early crystal
nuclei and retard crystal growth.[18]
Excretory Functions
Many drugs, as well as alcohol, are excreted into the saliva, which
could theoretically serve as a route of elimination. However,
since most of the saliva generated is swallowed rather than
expectorated, it is a very inecient disposal system, since the
substances would be absorbed and recycled. Clearly this is a
minor function.
Water Balance
Salivary glands are part of a control system for maintaining an
appropriate level of hydration. Thirst and need for uid intake
are usually signaled by dry mouth. This sensation results from
a diminution in resting secretion and activation of receptors
in the oral cavity. The signals to salivary glands result from
osmotic changes detected in hypothalamus or volemic changes
operating through the renin-angiotensin system of the kidney.
Thirst satiation and cessation of drinking are initiated by sensory
messages passing into the brain from taste receptors in the mouth.
Hormonal Function
Several studies have shown that the polypeptide hormone
known as an epidermal growth factor, is identical with human
urogastrone. Nerve growth factor and transforming growth
factor may be closely related as well. Human urogastrone, found
in very high concentrations in urine, is readily measurable in
the submandibular saliva. The major properties of urogastrone
include gastric cytoprotection and inhibition of gastric acid
Saliva and Periodontal Health
Role of saliva in oral diseases is most apparent when salivary ow
is markedly reduced. With respect to periodontal health, saliva
plays a role in two ways.
Pellicle and plaque formation
Saliva inuences supragingival plaque deposition and activity in
a variety of ways. It is predominantly involved in the rst step of
plaque formation, i.e., deposition of a pellicle (or cuticle) which
is a four stage process.
a. Bathing of the tooth surfaces by salivary uids which contain
abundant proteins.
b. Selective adsorption of certain negatively and positively
charged glycoproteins which act as an agglutinating base.
c. Loss of solubility of the adsorbed proteins by surface
denaturation and acid precipitation.
d. Alteration of the glycoproteins by enzymes from bacteria and
the oral secretions.
Now, this pellicle which is formed is actively involved
in the second stage of plaque formation which is “bacterial
1. The initial step in dental plaque formation involves the
adherence of bacteria to the salivary-coated tooth surface.
2. The bacteria that adhere to the pellicle initially are called the
“primary” colonizers which are usually Streptococcus sanguis
species followed by S. mutans.
3. Once an initial layer of bacteria attaches to the pellicle surface,
plaque can progress at a rapid pace, as many “secondary
colonizers” adhere to the primary bacteria and carve an
“ecological niche” for themselves. When we ask patients to
maintain a good oral hygiene, we are actually targeting to
counter this step.
4. In the third or maturation stage, saliva continues to
provide agglutinating substances and other proteins to
the intercellular matrix, and bacterial adhesion continues
e composition, function, and role of saliva in maintaining oral health Kumar, et al.
5. Salivary proteins and carbohydrates serve as a substrate
for metabolic activity of the bacteria. Salivary calcium,
phosphates, magnesium, sodium, and potassium become part
of the gel-like consistency of plaque and begin to inuence
its mineralization and demineralization. Mineral precipitate
results from a local rise in degree of saturation of calcium
and phosphates in saliva due to (a) increase of pH of saliva
(b) colloidal and particles in saliva which bind to calcium and
phosphates making super-saturated solution.[14,20-22]
Plaque mineralization and calculus formation
Salivary proteins such as esterase, pyrophosphates possibly
acid phosphatase and lysozyme play a role. Calcium crystals
are served by saliva. Persons who are heavy calculus formers are
known to have higher levels of salivary proteins (glycoproteins).
Therefore, oral hygiene instructions should be tailor-made to
suit each child’s need.
Recent concepts
The fact that α-amylase is found in acquired enamel pellicle
suggests that it has a role in bacterial adhesion. If it is so then
α-amylase is double danger, because it binds to bacteria in
the plaque, hold them together, and at the same time provide
additional glucose to those plaque microorganisms, and that too
include proximity to tooth surface. The resulting lactic acid is
added to the pool of acid that is already present.[23]
Saliva and Dental Caries
Evidence shows that saliva from caries-free individuals has higher
values of the following: (Compared to caries prone).
1. The increased rate of ow increased pH and increased
2. Higher calcium and phosphorous concentrations.
3. Higher ammonia concentration.
4. High concentrations of ATP and fructose diphosphate.
5. Increased aldolase activity and O2 uptake of bacteria.
6. Increased opsonin activity.
7. Increased general antibacterial activity.
8. Increased antibacterial activity specic to lactobacilli and
9. Higher number of intact leukocytes.
10. Dierence in proportion of epithelial cells to leukocytes.[23]
The saliva inuences on the caries process which is
fundamental, and the saliva also aects all the three components
of Keye’s classic Venn diagram of etiology of caries (tooth, plaque,
and substrate). The saliva also aects ow rates and clearance,
pH and buer capacity, calcium phosphate homeostasis and
eects on bacterial metabolism. The obvious manifestation
of the saliva/caries interactions includes adsorption to oral
tissues and elimination from the oral cavity. There are many
studies which had been done to relate certain aspects of salivary
output and composition to caries susceptibility. Most of those
studies were focused at either the physico-chemical properties
of saliva (ow rate, buer capacity) or denite components of
saliva with antimicrobial activity, such as salivary IgA, lactoferrin,
lysozyme and the salivary peroxidase-hypothiocyanite system.
The consensus relationship between caries experience and the
activity of any of the salivary antimicrobial proteins cannot be
validated, except hypothiocyanite system and IgA.[24]
The proline-rich proteins of the human parotid saliva
exhibits inherited polymorphisms [34] that have led to a number
of analysis done to correlate the genetic phenotype with caries
severity. Results have commonly been inconsistent in terms of
determining a relationship between prevalence of dental caries
(DMFS) and genetic phenotype of saliva.[13]
There are number of cross-sectional studies had been done to
correlate the compositions and ow of saliva with dental caries.
However, a basic aw of any such study is that the use of the DMF
index for evaluation of caries activity. The DMF index may be
a lifetime collective index of dental disease and treatment and
should have very little bearing activity at the precise purpose in
time. Similarly, a one-time determination of whole stimulated
salivary ow rate does not pass muster as a comprehensive
analysis of salivary function. Other more sensitive, indicator
of salivary activity have to be compelled to be used, probably
combining in vivo demineralization/remineralization models with
dierent indicators of dental caries activity along with recurrent,
standardized and comprehensive secretion collections.[25]
The use of saliva as a diagnostic uid
There has been a continuing hope over many years that saliva
could provide an alternative to blood for tests which might help
in the diagnosis of disease. This could occur only if a blood
component was transferable across the salivary gland epithelium
in proportion to its concentration in blood. This is true for
urea, glucose and the unbound steroid hormones. Only for the
some of these has saliva proved a useful medium for monitoring
concentrations. Glucose is used by the gland cells and appears in
saliva at around one-hundredth of its plasma concentration - too
low for easy measurement.[26]
Change in salivary composition in salivary gland disease
Sodium and chloride concentrations in the aected gland
secretions are raised in sialadenitis, suggesting that inammation
particularly aects the ductal system. This possibility is
reinforced by the observation that phosphate concentrations are
usually lowered.
Sjogren’s syndrome is a connective tissue disorder which
usually involves reduced secretion from the lacrimal and
salivary glands. Reduced salivary secretion causes a dry mouth
and is termed xerostomia. Again the principal changes in ionic
composition of saliva are increased concentration of sodium and
chloride and decreased concentration of phosphate. In addition,
there are changes in the relative concentrations of some minor
salivary proteins. These may have some diagnostic value. Salivary
gland neoplasms are uncommon, and there are few data available
on their eects on salivary compositions.[26]
Kumar, et al. e composition, function, and role of saliva in maintaining oral health
Radiation used in the treatment of neoplasm in the head and
neck region often results in radiation-induced damage to salivary
gland. This is seen as a marked reduction in ow rate, leading
to xerostomia. The small amount of saliva secreted has high
concentrations of sodium, chloride, calcium, and magnesium but
low concentrations of hydrogen carbonate. The low volume of
saliva and its poor buering power are associated with rampant
dental caries in these patients.
The best treatment for xerostomia patients seems
to be frequent use of mouthwashes with a high uoride
Clearly, saliva has profound eects on the mouth, however, as
Sreebny has noted, few dental practitioners hassle to raise the
required queries or build the required observations and/or
measurements to work out whether or not there’s any level of
exocrine gland hypofunction in their patients. Unfortunately, a
minimum of a part of the matter is that, for many half, there’s
not an easy x to a broken salivary ow. We will solely hope that
future trends in biological science analysis might permit the
xerostomic patient to regain perform. Until then, dentists ought
to be additional alert to their patient’s salivary function embrace
additional disciplined preventive practices to discourage the
negative eects of reduced salivary ow.
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... [12][13][14][15] Several studies have linked caries prevalence in DS with saliva composition. 11,16 Many components of saliva have direct and indirect roles in the caries process, one of which is Nitric Oxide (NO). NO plays an important role in the immune response, neuro transmission, and vasodilation in various body tissues. ...
... 12 A study of a high prevalence of caries in DS children mention several factors that caused it including lack of parental attention about the child's dental and oral health, a high-sugar diet, and irregular visits to the dentist. 16 Other studies also mention DS have higher number of cariogenic biofilms than normal children, which can be associated with the caries incidence in DS children. 17 DS children also show difficulty eating, chewing and swallowing food boluses, and inadequate nutrition. ...
... NO in the human body can be obtained from breathing, body metabolic products, and diet. 16 Human body metabolism can produce NO from endothelial cells and neural cells, but macrophages and other inflammatory cells can also induce NO synthesis and release. Most of the NO synthesis is produced from bacterial products. ...
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Down Syndrome (DS) is a genetic congenital disorder caused by additional third chromosome 21 (Trisomy 21). Dental manifestation includes malocclusion, delayed eruption, and open mouth posture. Combined with muscular hypotony and decrease of visual and audio vestibular capability, these factors make DS children struggle to maintain oral hygiene. Systemic factor such as hematological abnormalities, heart and immune defect also makes dental treatment plan more complex. Research of caries prevalence (as an infectious disease) in DS compared to healthy children have varied result. The purpose of this literature review is to describe the role of salivary Nitric Oxide (NO) and its effect on the caries status of children with Down syndrome (DS). Several studies have linked caries prevalence in DS children with saliva composition. Dental and systemic manifestation of DS cause changes in the oral ecosystem of DS, result in physiological changes in salivary flow rate and composition such as Nitric Oxide (NO). NO can be obtained from breathing, diet, and body metabolism. DS children prefer to consume foods rich in carbohydrates and refuse to consume vegetables and fruit. Since salivary NO can inhibit the growth of cariogenic bacteria such as Streptococcus mutants by forming reactive radical hydroxyl, inhibit respiration and DNA synthesis to damage the bacterial cell, this lack of fiber intake habit causes nutritional deficiencies from which NO obtained and may increase caries risk. This literature review concludes factors influencing the level of salivary Nitric Oxide and their effects on caries status of children with Down syndrome.
... Studies have found that the pH of saliva in the oral cavity under normal conditions is in the range of 6.2e7.6, with an average value of 6.7 [26]. The concentration of Н þ ions in the oral cavity affects the activity of saliva enzymes, the processes of enamel mineralization and remineralization, microcirculation, microflora activity, specific and nonspecific resistance of oral tissues [27]. The pH of the oral fluid (saliva) is constantly changing [28], e.g., at intervals after meal consumption, the value is close to neutral (6.5e6.8). ...
... Polyherbal toothpaste uses these agents and Himalayan rock salt, which has a certain percentage of fluoride to strengthen teeth [25,71,27]. Products of herbal origin such as chamomile, eucalyptus, fennel, echinacea, ginger, tincture of myrrh, tea tree oil, and clove oil are applied in oral hygiene maintenance [72]. ...
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Background: Discoloration of teeth occurs for various reasons. Common ingredients like substances from tea and coffee, as well as antibiotics like tetracycline, or food dyes, can percolate into the teeth, and, as such, these stains may persist in the porous structure of the enamel. Smoking is also contributory to dental discoloration, with toxins of tobacco smoke accumulating in a similar way. With aging, teeth tend to be discolored with accumulation of various stains in addition to the enamel gradually eroding to expose the yellow dentin. Highlight: This review focused on the effect of several natural ingredients with teeth-whitening properties and their daily clinical application. Metabolic dental bleaching mechanisms, as well as tooth discoloration and decay, were also reviewed. The current scientific literature (mostly from 2000 to 2020) was consolidated from manuscripts retrieved from Scopus, PubMed, ResearchGate, and Google Scholar. Conclusion: Natural teeth whitening effectively lightens the natural color of teeth without eroding dental surfaces. On the other hand, commercially available whiteners containing hydrogen peroxide and carbamide peroxide, in high concentrations, can lead to deproteinization and demineralization of teeth through oxidation processes. If used extensively, these compounds may cause a number of adverse effects. Alternative natural teeth-whiteners include ingredients like lemons, strawberries, oranges, papaya, and other fruits. Such natural ingredients offer a milder and safer way of whitening teeth than whiteners containing hydrogen peroxide or carbamide peroxide.
... Inside the oral cavity cells of the epithelium and salivary glands continuously produce and secrete antimicrobial proteins and AMPs into saliva and GCF (Figure 1) [18][19][20][21][22]. Predominant oral antimicrobial proteins include lysozyme, lactoferrin, and lactoperoxidase and reduce microbial growth by breaking down peptidoglycan residues, sequestering iron, and oxidating various microbial substrates, respectively. ...
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Candida albicans and Staphylococcus aureus account for most invasive fungal and bacterial bloodstream infections (BSIs), respectively. However, the initial point of invasion responsible for S. aureus BSIs is often unclear. Recently, C. albicans has been proposed to mediate S. aureus invasion of immunocompromised hosts during co-colonization of oral mucosal surfaces. The status of the oral immune system crucially contributes to this process in two distinct ways: firstly, by allowing invasive C. albicans growth during dysfunction of extra-epithelial immunity, and secondly following invasion by some remaining function of intra-epithelial immunity. Immunocompromised individuals at risk of developing invasive oral C. albicans infections could, therefore, also be at risk of contracting concordant S. aureus BSIs. Considering the crucial contribution of both oral immune function and dysfunction, the aim of this review is to provide an overview of relevant aspects of intra and extra-epithelial oral immunity and discuss predominant immune deficiencies expected to facilitate C. albicans induced S. aureus BSIs.
... Soft tissues protection is supplied towards desiccation, penetration, ulceration, and potential cancer-causing agents by using mucin and anti-proteases. A principal protective feature results from the salivary position in stabilizing the ecological balance within the oral cavity thru clearance, aggregation and decreased adherence by way of both immunological and non-immunological means in addition to direct antimicrobial activity [26]. ...
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This review paper elucidates the chemical composition of saliva and it roles in the oral cavity as lubrication and flushing action of the dentition to reduce the dental erosion. Update, Saliva also used as a diagnostic tools of different diseases. Additionally, this review deals with the pH of the saliva and its function to control the pH of the mouth during the day through the buffering system. Also it highlight the main manipulation methods used for saliva collection during research purposes.
... Kondisi rongga mulut yang selalu dibasahi oleh aliran saliva dan cairan rongga mulut lainnya membuat efektivitas obat-obat topikal menjadi menurun. 28 Mukobioadhesif digunakan untuk menghindari efek obat oleh aliran normal saliva dan cairan rongga mulut. Tujuan dari pemberian mukobiodhesif ini diharapkan agar efek terapeutik dari senyawa aktif dapat optimal mengenai area lesi ulser yang akan diobati. ...
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Lesi ulserasi merupakan penyakit jaringan lunak mulut yang banyak dijumpai. Pendekatan perawatan terhadap lesi ulserasi dengan menggunakan bioadhesif bertujuan untuk mendapatkan efek terapi maksimal dari suatu zat aktif. Tanaman gambir (Uncaria gambir) adalah suatu jenis tumbuhan yang banyak dikembangkan sebagai obat herbal karena memiliki senyawa aktif seperti katekin. Penelitian ini bertujuan untuk mengevaluasi efek mukobioadhesif ekstrak gambir terhadap penurunan rasa nyeri dan durasi penyembuhan pada lesi ulserasi rongga mulut. Desain penelitian ini adalah pretest-posttest control group. 24 sampel dibagi menjadi dua kelompok, kelompok yang diberi mukobioadhesif ekstrak gambir dan kelompok yang diberi mukobioadhesif plasebo selama 7 hari dengan aturan pakai 3 kali sehari. Tingkat keparahan rasa sakit yang diukur dengan skala VAS, luas lesi ulserasi, dan durasi penyembuhan dievaluasi dan dianalisis dengan SPSS ver. 22. Hasil penelitian menunjukkan bahwa penggunaan mukobiadhesif ekstrak gambir mampu mengurangi rasa sakit yang ditandai dengan penurunan skor VAS secara signifikan (p0,05) dan luas lesi yang ditandai dengan menurunnya rata-rata diameter lesi, serta mampu menurunkan durasi penyembuhan secara signifikan dibandingkan dengan plasebo. Dapat disimpulkan bahwa penatalaksanaan mukobioadhesif ekstrak gambir berpotensi dalam mengurangi rasa sakit dan mempercepat penyembuhan lesi ulserasi rongga mulut.
... Many plaque bacteria possess urease enzyme, which catalyzes the hydrolysis of urea to ammonia and carbon dioxide. The ammonia, being highly alkaline, neutralizes acids and causes pH rise, which may be a major impediment to the development of dental caries [40]. Moreover, since a high level of nitrogen compounds in saliva reflects their high concentration in blood plasma, it can be used to control the general condition of patients. ...
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There is growing interest for bioanalytical tools that might be designed for a specific user, primarily for research purposes. In this perspective, a new, highly stable potentiometric sensor based on glassy carbon/polyazulene/NH4+-selective membrane was developed and utilized for urease activity determination. Urease–urea interaction studies were carried out and the Michaelis–Menten constant was established for this enzymatic reaction. Biofunctionalization of the ammonium ion-selective sensor with urease lead to urea biosensor with remarkably good potential stability (drift coefficient ~0.9 mV/h) and short response time (t95% = 36 s). The prepared biosensor showed the Nernstian response (S = 52.4 ± 0.7 mV/dec) in the urea concentration range from 0.01 to 20 mM, stable for the experimental time of 60 days. In addition, some insights into electrical properties of the ion-to-electron transducing layer resulting from impedance spectroscopy measurements are presented. Based on the RCQ equivalent circuits comparison, it can be drawn that the polyazulene (PAz) layer shows the least capacitive behavior, which might result in good time stability of the sensor in respect to response as well as potential E0. Both the polyazulene-based solid-contact ion selective electrodes and urea biosensors were successfully used in trial studies for determination of ammonium ion and urea in human saliva samples. The accuracy of ammonium ion and urea levels determination by potentiometric method was confirmed by two reference spectrophotometric methods.
Objective: This study aimed to evaluate the effect of methanol (70% v/v), ethanol (80% v/v), dimethyl sulfoxide (DMSO; 100% v/v) extracts of ginger rhizome (GR), and 6-shogaol on the pilocarpine-stimulated salivary flow rate in C57BL/6 mice. Methods: Three extracts of ginger (Zingiber officinale) rhizome prepared by maceration using the respective solvents and 6-shogoal were reconstituted in normal saline with 0.2% DMSO. Thirty C57BL/6 15-week-old mice were divided into 5 groups: Group 1, saline; Group 2, 70% methanol extract; Group 3, 80% ethanol extract; Group 4, 100% DMSO extract; and Group 5, 6-shogaol. The baseline pilocarpine-stimulated salivary flow rate was measured at the age of 15 weeks (15th week), and treatment solutions were administered by intraperitoneal injection from the 16th to 18th week. The stimulated salivary flow rate during treatment weeks was recorded for each group, and its difference with baseline was analysed using paired-sample t test. The change in salivary flow rate between the treatment groups and the control group was analysed using one-way analysis of variance. Results: Groups 2, 3, 4, and 5 showed a significant increase in salivary flow rate when compared to baseline (P < .05). The increase in salivary flow rate in all 4 treatment groups was significant when compared to the control group (P < .05). Group 4 produced the highest increase in salivary flow rate; however, the differences amongst the treatment groups did not reach statistical significance (P > .05). Conclusions: All GR extracts (70% methanol, 80% ethanol, 100% DMSO) and 6-shogaol were equally effective in increasing the pilocarpine-stimulated salivary flow rate in C57BL/6 mice when administered systemically as a sustained dose for 3 weeks.
The ingestion of certain trace metals has been a major concern of the world and there have been links to cancer, renal failure, anemia, cardiovascular and reproductive complications. Pacifiers are amongst the childcare objects that may expose children to potentially toxic metals through mouthing behaviors. Despite high levels of hazardous chemicals reported in some childcare products including pacifiers; there has been limited information on the chemical species formed in saliva and as a result their bioavailability levels. Using the Joint Expert Speciation System, this study determined chemical speciation and predicted bioavailability at a range of 18-92% for cadmium and 1-23% for lead of the total metal concentrations through the creation of simulated saliva models at low and high pH. The degree of predicted uptake using a net-neutral species approach was dependent on the total concentrations of lead and cadmium within a standard range of low molecular mass ligands and the pH of the saliva. These saliva models predicted cadmium to be more bioavailable than lead, indicating there may be an elevated risk from the mouthing action of pacifiers or similar items containing cadmium compared to lead. This study, therefore, offers regulatory bodies opportunities to strengthen safety compliance monitoring for materials used in pacifiers.
Introduction The submandibular gland is commonly removed during neck dissection in patients with head and neck cancer. The patient experiences various complications due to the removal of the submandibular gland. Therefore, the necessity of submandibular gland removal should be evaluated. This study aimed to was to determine the frequency of submandibular gland (SMG) involvement in patients with oral cavity squamous cell carcinoma (SCC). Methods In this retrospective study, medical records of patients with oral cavity cancer who were referred to Amir Alam Hospital between 2015 and 2020 were reviewed. Patient data includes surgical report, histopathology report (tumor size, number of lymph nodes involved, and SMG tumor involvement), Tumor Location, History of Smoking, History of Opium, and Alcohol consumption was extracted from patients' medical records and statistically analyzed using SPSS software version 20. Results Of the total 60 patients, 24 (40%) were female and 36 (60%) were male. Smoking was reported in 55% of patients with a mean of 4.11 pack-year. Alcohol and opium use was observed in 18.3% and 26% of patients. The majority of patients (78.3%) had tongue cancer. More than half of the patients (53.3%) reported tumors of 2 cm or smaller, and 16.7% of patients had tumors larger than 4 cm. The majority of patients (80.3%) did not have cervical lymph node metastasis, 13.1% had 1–2 involved lymph nodes and 4.9% had 3 to 6 involved lymph nodes and there were no cases of metastasis to more than 6 lymph nodes. Finally, no individual had submandibular gland involvement, ie 100% of patients had no submandibular gland metastasis. Conclusion The results confirmed that SMG involvement is very rare in patients with oral SCC and therefore it is not necessary to remove the gland as part of treatment. Preservation of the submandibular gland prevents complications related to the removal of this gland and reduces morbidity and increases the quality of life of patients after surgery.
Nature's demands on salivary glands are extensive and diverse and range from the reptilian need for a venomous drop to incapacitate its prey to the 100 quarts that ruminants require to digest a day's grazing. Other species depend on saliva not for survival, but for improving the quality of life, using the fluid for functions varying from grooming and cleansing to nest-building. Humans can manage without saliva; its loss is not life-threatening in any immediate sense, but it results in a variety of difficulties and miseries. Oral digestion per se is only of marginal importance in humans, but saliva is important in preparing food for mastication, for swallowing, and far normal taste perception. Without saliva, mealtimes are difficult, uncomfortable, and embarrassing. The complex mix of salivary constituents provides an effective set of systems for lubricating and protecting the soft and hard tissues. Protection of soft tissues is afforded against desiccation, penetration, ulceration, and potential carcinogens by mucin and anti-proteases. Saliva can encourage soft tissue repair by reducing clotting time and accelerating wound contraction. A major protective function results from the salivary role in maintenance of the ecological balance in the oral cavity via: (1) debridement/lavage; (2) aggregation and reduced adherence by both immunological and non-immunological means; and (3) direct antibacterial activity. Saliva also possesses antifungal and anti-viral systems. Saliva is effective in maintaining pH in the oral cavity, contributes to the regulation of plaque pH, and helps neutralize reflux acids in the esophagus. Salivary maintenance of tooth integrity is dependent on: (I) mechanical cleansing and carbohydrate clearance; (2) post-eruptive maturation of enamel; (3) regulation of the ionic environment to provide a remineralizing potential without spontaneous precipitation; and (4) pellicle deposition and limitation of acid diffusion. Saliva also plays a role in water balance, can serve in a limited way in excretion, and has possible hormonal function in the gastro-intestinal tract.
The local, saliva-associated defense mechanisms of 28 juvenile periodontitis (JP) patients and their age- and sex-matched controls were studied. Lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, and thiocyanate concentrations were determined from both whole saliva and parotid saliva. The total concentrations of salivary IgA, IgG, and IgM were assayed. The periodontal condition and the salivary flow rates were registered. Among the JP patients, a significantly elevated concentration of IgG was found in parotid saliva but not in whole saliva. Salivary peroxidase activities were significantly low both in the whole and in the parotid saliva samples of the JP patients, and leukocyte-derived myeloperoxidase was present in significantly low amounts in whole saliva of these patients. Because both glandular (salivary peroxidase) and polymorphonuclear-cell-derived (myeloperoxidase) enzyme activities were low among the JP patients, suppressed peroxidase-mediated host defense mechanisms could be characteristic of JP.
The serums of 269 children, ranging in age from early infancy to 16 years, were examined by the cell wall agglutination test for antibodies against four strains of oral streptococci shown to induce caries in experimental animals. Results indicated that antibody to cariogenic streptococci was present in the serum of the children, and that the antibody titers increased with the age of the child and with the development of the dentition. No correlation was found in this study between caries activity and the levels of serum antibody.
Human salivary PRPs are determined by six closely linked genes on chromosome 12p13.2. The many PRPs show complex electrophoretic patterns that differ between individuals and reflect numerous genetic polymorphisms. Frequent length and null polymorphisms are common among PRPs. Common themes emerge as a background for these PRP polymorphisms. First, posttranslational proteolysis occurs with double-banded patterns among acidic PRPs and the generation of numerous basic PRPs derived from precursor proteins. Specific mutations may interfere with proteolysis, preventing generation of double-banded acidic PRPs (as with the Pa protein) or of small basic PRPs from precursor proteins (as with Pm proteins). Second, single cysteine substitutions in PRPs (Pa from PRH1 and G1 8 from PRB3) may lead to disulfide bonded homodimers as well as heterodimers with salivary peroxidase. Third, frequent homologous and unequal crossing-over within the PRP gene cluster leads to frequent protein size-variants (intragenic events as with the G1 protein variants) and the generation of the PRB2/1 fusion gene (intergenic event) with deletion of the PRB1 coding region and absence of multiple PRB1 coded proteins (Ps, Pm, Pe) in PRB2/1 homozygotes. Fourth, null mutations may also be produced (as with PsO and G1 0) by single nucleotide changes.
Both intra- and inter-individual variation in salivary flow rate, buffer effect, and the levels of salivary mutans streptococci and lactobacilli were analyzed in 128 11-year-old children. The follow-up period was 9 months, with six saliva samplings done at regular intervals. Inter-individual variation was relatively large in paraffin-stimulated salivary flow rate: low (< 1.0 ml/min) and high (> or = 2.0 ml/min) flow rates were measured in 18% and 13% of the children, respectively. Intraindividual variation during the follow-up period was found in 63% of the boys and in 73% of the girls. The buffer effect stayed stable in all samplings in 59% of the boys and in 42% of the girls. Buffer effect was significantly (p < 0.001) lower in girls than in boys. Mutans streptococci were analyzed by a chair-side method (Strip mutans test) and by cultivation on mitis-salivarius-bacitracin (MSB) agar plates. The results of the two methods correlated highly significantly (r = 0.79, p < 0.001). With the Strip mutans test no variation in test scores occurred in 49% of all subjects in all six samplings, whereas the respective percentage for MSB scores was only 19%. No variation in salivary lactobacilli occurred in only 18% of the subjects, and in 13% the intraindividual variation was as high as > or = 3 logs. These results show that in young teenagers with a developing dentition, simultaneous changes in behavioral, hormonal, and dietary factors make single-point measurements of salivary factors too unreliable for caries-diagnostic or predictive purposes.
For practical reasons the numbers of mutans streptococci (MS) and lactobacilli (LB) in plaque are commonly estimated from saliva samples. The saliva counts are considered to be a reasonable indicator of the entire dentition's total microbial load. However, the value of salivary counts for explaining and predicting caries have been found to be low. There was therefore reason to compare the relationships between caries on the one hand and, on the other, the number of MS or LB in plaque and in saliva, respectively, in order to assess their relative merits for explaining the variation in caries, both in a total material and in subgroups with less favourable oral hygiene. Sixty children aged 14-15 years participated in the study. Caries and plaque were registered and the number of MS and LB was estimated in total plaque and in stimulated saliva samples. The results showed that the number of MS or LB in plaque did not explain the variation in caries to a greater degree than did the salivary counts. For both bacteria the explanatory values increased, as expected, in subgroups with less favourable oral hygiene, but not even at this higher level of explanation was there any difference between plaque and saliva. The LB count was a stronger explanatory variable than the MS count. It was concluded that the number of MS and LB, estimated in total plaque as well as in saliva samples, is not a useful tool in prediction.
Seven cases of absence of two or more salivary glands in children are presented. In six of the cases the condition was congenital and in one it was the result of surgery to the submandibular ducts. The patients had been referred for treatment of rampant dental caries and were reviewed for periods ranging from 6 months to 15 years 9 months. The diagnosis of absence of salivary glands was based on careful inspection and palpation of the duct and duct orifice of each gland. One patient had dry lips and three had dry mouths, but none complained of excessive thirst or difficulty with mastication or swallowing. All the patients had very poor oral hygiene and rampant dental caries. The presence of carious lesions in mandibular incisors, particularly when their severity exceeds those present elsewhere in the mouth, should alert the clinician to the possibility that salivary glands may be absent.