ArticlePDF AvailableLiterature Review

Abstract and Figures

The aim of this study was to perform a literature review about the composition and functions of saliva as well as describe the factors that influence salivary flow (SF) and its biochemical composition. Saliva represents an increasingly useful auxiliary means of diagnosis. Sialometry and sialochemistry are used to diagnose systemic illnesses, monitoring general health, and as an indicator of risk for diseases creating a close relation between oral and systemic health. This review provides fundamental information about the salivary system in terms of normal values for SF and composition and a comprehensive review of the factors that affect this important system. Since several factors can influence salivary secretion and composition, a strictly standardized collection must be made so the above-mentioned exams are able to reflect the real functioning of the salivary glands and serve as efficient means for monitoring health. Since many oral and systemic conditions manifest themselves as changes in the flow and composition of saliva the dental practitioner is advised to remain up-to-date with the current literature on the subject.
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1
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
Saliva Composition and Functions:
A Comprehensive Review
Aim:
The aim o
f
this stud
y
was to per
f
orm a literature review about the composition and
f
unctions o
f
saliva as
w
ell as describe the factors that influence salivar
y
flow (
S
F) and its biochemical composition
.
B
ack
g
round
:
S
aliva represents an increasin
g
ly useful auxiliary means of dia
g
nosis.
S
ialometry and
sialochemistry are used to diagnose systemic illnesses, monitoring general health, and as an indicator o
f
risk
f
or
iseases creatin
a close relation
etween oral an
systemic
ealt
R
ev
i
ew
:
This review provides
f
undamental in
f
ormation about the salivar
y
s
y
stem in terms o
f
normal values
f
or
S
F and composition and a comprehensive review of the factors that affect this important s
y
stem
.
C
onclusion
:
S
ince several factors can influence salivar
y
secretion and composition, a strictl
y
standardized
c
ollection must be made so the above-mentioned exams are able to re
f
lect the real
f
unctionin
g
o
f
the salivary
g
lands and serve as e
ff
icient means
f
or monitorin
g
health
.
C
linical Si
g
nificance:
S
ince many oral and systemic conditions manifest themselves as chan
g
es in the flow
a
nd composition o
f
saliva the dental practitioner is advised to remain up-to-date with the current literature on
t
h
e su
b
ject
.
K
e
y
words
:
S
aliva, salivary
g
lands, salivary proteins, lysozyme, lactoferri
n
C
itation: de Almeida PDV, Gré
g
io AMT, Machado M
Â
N, de Lima AAS, Azevedo LR. Saliva Composition and
Functions: A Comprehensive Review. J Contemp Dent Pract 2008 March; (9)3:072-080
.
Abstract
2
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
Introduction
S
alivar
y
fluid is an exocrine secretio
n
1,2
cons
i
st
i
n
g
o
f
approximately 99% water, containin
g
a variety o
f
electrol
y
tes (sodium, potassium, calcium, chloride,
ma
g
nesium, bicarbonate, phosphate) and proteins,
r
epresente
d
b
y enzymes, immuno
g
lo
b
ulins an
d
other antimicrobial
f
actors, mucosal glycoproteins,
traces o
f
albumin and some pol
y
peptides and
oli
g
opeptides o
f
importance to oral health. There
a
re also glucose an
d
nitrogenous pro
d
ucts, suc
h
a
s urea an
d
ammonia
.
3,4
T
h
e components interact
a
nd are responsible
f
or the various
f
unctions
a
ttri
b
ute
d
to
s
aliva
.
2
Total or whole saliva re
f
ers to the complex mixture
o
f
f
luids
f
rom the salivary glands, the gingival
f
old,
oral mucosa transudate
,
in addition to mucous o
f
t
h
e nasal cavit
y
an
d
p
h
ar
y
nx, non-a
dh
erent oral
bacterial,
f
ood remainders, desquamated epithelial
a
nd blood cells
,
as well as traces o
f
medications or
c
h
emical pro
d
ucts
.
3
-9
A
t rest, wit
h
out exo
g
enous or p
h
armacolo
g
ical
s
timulation, t
h
ere is a small, continuous salivar
y
f
low (
S
F), denominated basal unstimulated
s
ecretion, present in the
f
orm o
f
a
f
ilm that covers,
moisturizes
,
an
d
lu
b
ricates t
h
e oral tissues.
Wh
ereas, stimulate
d
saliva is pro
d
uce
d
in t
h
e
f
ace o
f
some mechanical,
g
ustatory, ol
f
actory, or
p
h
armacolo
g
ical stimulus, contri
b
utin
g
to aroun
d
8
0% to 90% o
f
dail
y
salivar
y
production
.
2
-4,9-1
2
A
h
ealt
hy
person’s mean
d
ail
y
saliva pro
d
uction
r
anges
f
rom 1 to 1.5L
.
4
The
S
F index is a
parameter allowin
g
stimulate
d
an
d
unstimulate
d
s
aliva
f
low to be classi
f
ied as normal
,
low
,
or
ver
y
low (h
y
posalivation)
.
8
In a
d
ults
,
normal
total stimulated
S
F ran
g
es from 1 to 3 mL/
min, low ran
g
es
f
rom 0.7 to 1.0 mL/min, while
h
y
posalivation is characterized b
y
a
S
F of less
than 0.7 mL/min. The normal unstimulated
S
F
r
an
g
es
f
rom 0.25 to 0.35 mL/min, low ran
g
es
f
rom 0.1 to 0.25 mL/min, while h
y
posalivation
is characterized b
y
a
S
F of less than 0.1 mL/
m
i
n
.
8,
1
1
However
,
the values denominated “normal”
f
or stimulated and unstimulated
S
F exhibit a
l
ar
g
e biolo
g
ical variation. Thus, individual
S
F
must
b
e monitore
d
re
g
ularly an
d
not
d
etermine
d
a
s
normal” or
abnormal”, based onl
y
on one
measuremen
t.
9,
11
S
aliva is critical for preserving and maintaining
the health o
f
oral tissues and has been used as a
s
ource o
f
non-invasive investi
g
ation o
f
metabolism
a
nd the elimination o
f
many drugs. However, it
r
eceives little attention until its quantit
y
d
iminis
h
es
or its qualit
y
b
ecomes altere
d.
4,
7
,
11
,
13
A
t present, saliva represents an increasin
g
ly
u
se
f
ul auxiliary means o
f
dia
g
nosis
.
14
Man
y
r
esearchers have made use o
f
sialometr
y
and
s
ialoc
h
emistry to
d
ia
g
nose systemic illnesses,
monitorin
g
g
eneral health, and as an indicator o
f
r
isk
f
or diseases creating a close relation between
oral an
d
s
y
stemic
h
ealt
h.
15
However
,
since several
f
actors can in
f
luence salivar
y
secretion and
composition a strictl
y
stan
d
ar
d
ize
d
collection must
b
e ma
d
e so t
h
e a
b
ove-mentione
d
exams are a
b
le
to re
f
lect the real
f
unctionin
g
o
f
the salivary
g
lands
a
nd serve as an e
ff
icient means
f
or monitoring
health. There
f
ore
,
the aim o
f
this literature review
w
as to investi
g
ate the composition and
f
unctions
o
f
s
aliva a
s
well a
s
de
s
cribe the
f
actor
s
that
influence
S
F and its biochemical composition
.
Saliva Functions and Composition
Taste
The
S
F initiall
y
formed inside the acini is
isotonic wit
h
respect to plasma. However, as it
r
uns throu
g
h the network o
f
ducts, it becomes
hy
potonic
.
6,9,16,17
The h
y
potonicit
y
of saliva (low
l
evels of
g
lucose, sodium, chloride, and urea)
a
nd its capacit
y
to provide the dissolution o
f
s
u
b
stances allows t
h
e gustatory
b
u
d
s to perceive
different flavors. Gustin, a salivar
y
protein,
a
ppears to be necessary
f
or the
g
rowth and
maturation o
f
the
s
e bud
s.
1
,
4
,13,1
8
3
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
Buffer Capacity
S
aliva behaves as a buffer s
y
stem to protect the
m
o
ut
h
8,
19
as
f
ollows:
1. It prevents colonization
by
potentiall
y
pat
h
o
g
enic microor
g
anisms
b
y
d
enyin
g
t
h
em
o
ptimization o
f
environmental conditions
.
2.
S
aliva buffers (neutralizes) and cleans
t
h
e aci
d
s pro
d
uce
d
b
y aci
d
o
g
enic
microor
g
anisms, t
h
us, preventin
g
enamel
de
min
e
ralizati
o
n
.
13
It is important to emphasize bio
f
ilm thickness,
a
nd the number o
f
bacteria present determines
the e
ff
icac
y
o
f
salivar
y
bu
ff
ers
.
4
N
egatively loa
d
e
d
resi
d
ues on t
h
e salivary
proteins work as buffers.
S
ialin, a salivar
y
pepti
d
e, plays an important role in increasin
g
the bio
f
ilm pH a
f
ter exposure to
f
ermentable
car
b
o
hyd
rates
.
8,
1
3
U
rea is another bu
ff
er present in total salivar
y
f
luid which is a product o
f
aminoacid and
protein cata
b
olism t
h
at causes a rapi
d
increase
in bio
f
ilm pH by releasing ammonia and
car
b
on
d
ioxi
d
e w
h
en
hyd
rol
y
ze
d
by
b
acterial
u
reases
.
3,
5
,
8
,
9
,
24
,
2
5
C
hildren with chronic renal
insu
ff
icienc
y
present with less caries than
health
y
children, due to the increased levels o
f
s
a
li
var
y
urea
.
2
6
A
mmonia, a product o
f
urea and aminoacid
meta
b
olism, is potentially cytotoxic to
g
in
g
ival
tissues. It is an important
f
actor in the initiation
o
f
g
in
g
ivitis because it may increase the
permeabilit
y
o
f
the sulcular epithelium to other
toxic or antigenic su
b
stances in a
dd
ition to t
h
e
f
ormation o
f
dental calculus
.
2
7
T
h
e car
b
onic aci
d
-
b
icar
b
onate s
y
stem is t
h
e
most important bu
ff
er in stimulated saliva, while
in unstimulate
d
saliva it serves as t
h
e p
h
osp
h
ate
bu
ff
er s
y
stem
.
8
Integrity of Tooth Enamel
S
aliva plays a fundamental role in maintaining
the physical-chemical inte
g
rity o
f
tooth
enamel
b
y mo
d
ulatin
g
remineralization an
d
demineralization. The main
f
actors controlling
the stabilit
y
o
f
enamel h
y
drox
y
apatite are the
a
ctive concentrations
f
ree o
f
calcium, phosphate,
a
nd
f
luoride in solution and the salivar
y
pH
.
1
1,28
Protection and Lubrication
S
aliva forms a seromucosal covering that
l
u
b
ricates an
d
protects t
h
e oral tissues a
g
ainst
i
rr
i
tat
i
n
g
a
g
ents
.
18,
19
T
h
is occurs
d
ue to mucins
(proteins with high carbohydrate content)
r
esponsible
f
or lubrication, protection a
g
ainst
deh
y
dration, and maintenance o
f
salivar
y
visco
-
elasticit
y
. T
h
e
y
also selectivel
y
mo
d
ulate t
h
e
a
dhesion o
f
microor
g
anisms to the oral tissue
s
ur
f
aces
,
which contributes to the control o
f
bacterial and
f
ungal colonization. In addition, they
protect t
h
ese tissues a
g
ainst proteolytic attacks
b
y microor
g
anisms. Mastication, speec
h
, an
d
deglutition are aided by the lubricant e
ff
ects o
f
t
h
ese proteins
.
1,
4
,
8
,
19-
22
Dilution and Cleaning
S
u
g
ars in their free form are present in total
s
timulate
d
an
d
unstimulate
d
saliva at a mean
concentration o
f
0.5 to 1 mg/100mL
.
3
,
5
Hig
h
concentrations o
f
su
g
ar in saliva mainly occur a
f
ter
th
e
intak
e
of
food
an
d
d
rink
.
3,
5
It is known t
h
ere is
a
correlation
b
etween t
h
e glucose concentration in
the blood and salivar
y
f
luid, particularl
y
in diabetics,
but because this is not always si
g
ni
f
icant, saliva is
not used as a means o
f
monitoring blood sugar
.
23
In addition to dilutin
g
substances, its
f
luid
consistency provides mechanical cleansing o
f
t
h
e resi
d
ues present in t
h
e mout
h
suc
h
as non
-
a
dherent bacteria and cellular and
f
ood debris.
S
F tends to eliminate excess carboh
y
drates, thus,
l
imitin
g
the availability o
f
su
g
ars to the bio
f
ilm
microor
g
anisms. The
g
reater the
S
F, the
g
reater
the cleaning and diluting capacity; there
f
ore, i
f
chan
g
es in health status cause a reduction in
S
F,
there would be a drastic alteration in the level o
f
oral cleaning
.
8,12,13,18,19
4
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
N
ormal salivar
y
pH is
f
rom 6 to 7 and varies
in accordance with the
S
F, from 5.3
(
low flow
)
to 7.8 (peak flow). There are various sources
o
f
hydrogen ions in oral
f
luids: secretion by
the salivary
g
lands in the
f
orm o
f
or
g
anic and
inor
g
anic aci
d
s, pro
d
uction
b
y t
h
e oral micro
b
iota,
or acquisition through
f
ood. These ions in
f
luence
the equilibrium o
f
calcium phosphates in the
enamel. The hi
g
her the concentration o
f
hydro
g
en
ions, t
h
e lower t
h
e pH an
d
vice versa
.
4
,
8
A
t
hi
g
her
f
lows o
f
stimulated salivary secretion, the
concentration o
f
bicarbonate ions is hi
g
her, the pH
a
lso rises, and the bu
ff
ering power o
f
the saliva
increases
d
ramaticall
y.
11
Digestion
S
aliva is responsible for the initial di
g
estion of
s
tarch,
f
avorin
g
the
f
ormation o
f
the
f
ood bolus
.
1
3
,
1
7
This action occurs mainl
y
b
y
the presence o
f
t
h
e
d
i
g
estive enzyme
α
-am
y
lase (pt
y
alin) in the
composition o
f
the saliva. Its biolo
g
ical
f
unction is
to
d
ivi
d
e t
h
e starc
h
into maltose
,
maltotriose
,
an
d
d
extrins. T
h
is enzyme is consi
d
ere
d
to
b
e a
g
oo
d
indicator o
f
properly
f
unctionin
g
salivary
g
lands
,
29
contributing 40% to 50% o
f
the total salivary
protein pro
d
uce
d
b
y t
h
e
g
lan
d
s. T
h
e
g
reater
part of this enz
y
me (80%) is s
y
nthesized in the
paroti
d
s an
d
t
h
e remain
d
er in t
h
e su
b
man
d
i
b
ular
g
lan
d
s. Its action is inactivate
d
in t
h
e aci
d
portions
o
f
the
g
astrointestinal tract and is consequently
l
imit
ed
t
o
t
he
m
o
ut
h.
3
,4,8,12,21
Tissue Repair
A
tissue repair
f
unction is attributed to saliva since
clinically the bleedin
g
time o
f
oral tissues appears
to
b
e s
h
orter t
h
an ot
h
er tissues. W
h
en saliva is
experimentally mixe
d
wit
h
b
loo
d
, t
h
e coagulation
time can be
g
reatly accelerated (althou
g
h
the resultin
g
clot is less solid than normal).
Experimental stu
d
ies in mice
h
ave s
h
own woun
d
contraction is si
g
ni
f
icantly increased in the
presence o
f
saliva due to the epidermal
g
rowth
f
actor it contains which is produced b
y
the
s
u
b
man
d
i
b
ular
g
lan
d
s
.
1
3
Antibacterial Properties and Participation in
Film and Calculus Formation
S
aliva contains a spectrum of immunolo
g
ic and
non-immunologic proteins wit
h
anti
b
acterial
properties. In a
dd
ition, some proteins are
necessary
f
or inhibitin
g
the spontaneous
precipitation o
f
calcium and phosphate ions in
The high concentrations o
f
calcium and phosphate
in saliva
g
uarantee ionic exc
h
an
g
es
d
irecte
d
towards the tooth sur
f
aces that be
g
in with tooth
eruption resulting in post-eruptive maturation.
R
emineralization o
f
a carious tooth be
f
ore
cavitation occurs is possi
b
le, mainl
y
d
ue to t
h
e
a
vailabilit
y
o
f
calcium and phosphate ions in
s
a
li
va
.
8,
1
3,
1
8
The concentration o
f
salivar
y
calcium varies
w
ith the
S
F
8,
11
and is not a
ff
ected b
y
diet.
H
owever, diseases such as c
y
stic
f
ibrosis and
s
ome me
d
ications suc
h
as pilocarpine cause
a
n increase in calcium levels. Depen
d
in
g
on t
h
e
pH, salivar
y
calcium can
b
e ionize
d
or linke
d
.
Ionized calcium is important
f
or establishing
equili
b
rium
b
etween t
h
e calcium p
h
osp
h
ates
o
f
enamel and its ad
j
acent liquid. Non-ionized
calcium can be linked to inorganic ions (inorganic
phosphate, bicarbonate, fluoride), to small or
g
anic
ions
(
citrate
)
, and to macromolecules
(
statherin,
histidine-rich peptides, and proline-rich proteins).
A
special case o
f
the combination o
f
calcium is
its stron
g
link wit
h
α
-amilase
,
w
h
ere it acts as a
co-
f
actor necessar
y
f
or the enz
y
me
f
unction
.
8
,1
1
Inor
g
anic orthophosphate
f
ound in saliva consists
of phosphoric acid (
H
3
P
O
4
) and primar
y
(
H
2
P
O
4
-
),
s
econdar
y
(HPO
4
2-
), and tertiar
y
(PO
4
3-
) inor
g
anic
phosphate ions. The concentrations o
f
these ions
d
epen
d
on salivar
y
pH an
d
var
y
in accor
d
ance
w
ith the
S
F. As the flow increases
,
the total
concentration o
f
inor
g
anic phosphate diminishes
.
8,
11
The most important biological
f
unction o
f
this ion is
to maintain the dental structure. Another
f
unction
,
discussed previousl
y
, is its bu
ff
er capacit
y
, relevant
onl
y
in unstimulated
S
F
.
8
,1
1
The presence o
f
f
luoride in saliva, even at
physiologically low levels, is decisive
f
or the
s
tabilit
y
o
f
dental minerals. Its concentration in
total saliva is relate
d
to its consumption. It is
dependent on the
f
luoride in the environment,
especially in drinkin
g
water. Other sources are
a
lso important, such as denti
f
rices and other
pro
d
ucts use
d
in caries prevention. T
h
e presence
o
f
f
luoride ions in the liquid phase reduces mineral
l
oss durin
g
a drop in bio
f
ilm pH, as these ions
diminish the solubilit
y
o
f
dental h
y
drox
y
apatite,
makin
g
it more resistant to
d
emineralization. It
has also been demonstrated
f
luoride reduces the
production o
f
acids in bio
f
ilm
.
4
,8,11,28
5
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
s
tructure lu
b
rication, an
d
it is pro
b
a
b
le
b
ot
h
a
re important in the
f
ormation o
f
acquired
f
ilm.
A
nother
f
unction proposed
f
or the proline-rich
proteins is t
h
e capacit
y
to selectivel
y
me
d
iate
bacterial adhesion to tooth sur
f
aces
.
3
,
4
,
8
,22
T
h
e c
y
statins are also relate
d
to acquire
d
f
ilm
f
ormation and to h
y
drox
y
apatite cr
y
stal
equili
b
rium. Due to its proteinase in
h
i
b
itin
g
properties, it is surmise
d
t
h
ey act in controlling
proteo
ly
t
i
c act
i
v
i
t
y.
3,
4
,
8
,22,
3
1
The histatins, a
f
amil
y
o
f
histidine-rich
pepti
d
es
,
22
h
ave antimicro
b
ial activity a
g
ainst
s
ome strains o
f
Streptococcus mutans
32
s
s
an
d
inhibit hemoagglutination o
f
the periopathogen
P
orp
h
yromonas g
i
ng
i
va
lli
s
.
33
T
h
e
y
neutralize t
h
e
l
ipopol
y
saccharides o
f
the external membranes o
f
Gram-negative bacteria
34
an
d
are potent in
h
i
b
itors
of
Candida albicans
growth and development.
s
35
The bactericidal and
f
un
g
icidal e
ff
ects occur
through the union o
f
positively loaded histatins
w
it
h
t
h
e
b
iolo
g
ical mem
b
ranes resultin
g
in t
h
e
destruction o
f
their architecture and alterin
g
their permeabilit
y
. Other functions attributed to
these peptides are: participation in acquired
f
ilm
f
ormation and inhibition o
f
histamine release
b
y t
h
e mastocytes, suggesting a role in oral
in
f
lammati
o
n
.
21
S
alivary agglutinin, a highly glycosylated protein
f
requentl
y
associated with other salivar
y
proteins
a
nd with secretory I
g
A, is one o
f
the main
s
alivar
y
components responsible
f
or bacteria
aggl
ut
i
nat
i
on
.
22
Factors Influencing Salivary Flow and
Composition
S
everal factors ma
y
influence
S
F and its
composition. As a result, t
h
ese vary greatly
a
mon
g
in
d
ivi
d
uals an
d
in t
h
e same in
d
ivi
d
ual
u
nder di
ff
erent circumstances
.
3,
5
,
9
,
10
,
36
Individual Hydration
The de
g
ree o
f
individual
hyd
ration is t
h
e most
important
f
actor that
inter
f
eres in salivar
y
s
ecretion
.
10
W
h
en t
h
e
b
o
dy
w
ater content is re
d
uce
d
by
8
%,
S
F virtuall
y
diminishes to
zero, w
h
ereas
hy
per
hyd
ration
causes an increase in
S
F
.
9
Durin
g
d
e
h
y
d
ration,
t
h
e salivary glan
d
s an
d
in t
h
eir secretions. Bot
h
the acquired
f
ilm and the bio
f
ilm have proteins
derived
f
rom saliva
.
3
,
1
1
S
ecretory immuno
g
lobulin A (I
g
A) is the lar
g
est
immunolo
g
ic component o
f
saliva. It can
neutralize viruses,
b
acterial, an
d
enz
y
me toxins.
It serves as an antibody
f
or bacterial anti
g
ens
a
n
d
is a
b
le to a
gg
re
g
ate
b
acteria, in
h
i
b
itin
g
t
h
eir a
dh
erence to oral ti
ss
ue
s.
4,11,13,21
O
ther
immunolo
g
ic components, such as I
g
G and I
g
M,
occur in less quantity and probably ori
g
inate
f
rom
gingival
f
luid
.
3
,
4
A
mon
g
t
h
e non-immunolo
g
ic salivary protein
components, there are enz
y
mes (l
y
soz
y
me,
l
actoferrin, and peroxidase), mucin
g
lycoproteins,
agg
lutinins,
h
istatins, proline-ric
h
proteins,
s
tat
h
erins, an
d
c
y
statins
.
11,21
Ly
soz
y
me can h
y
drol
y
ze the cellular wall o
f
some
b
acteria, an
d
b
ecause it is strongly cationic, it
can activate the bacterial
autolisines” which are
ab
le to
d
estro
y
b
acterial cell wall components.
Gram-negative bacteria are more resistant to
this enz
y
me due to the protective
f
unction o
f
their external lipopol
y
saccharide la
y
er.
O
ther
a
ntibacterial mechanisms have been proposed
f
or
t
h
is enzyme, suc
h
as a
gg
re
g
ation an
d
in
h
i
b
ition
of
bact
e
rial a
d
h
e
r
e
nc
e.
3,
4
,
8
,
21
,
2
2
L
acto
f
errin links to
f
ree iron in the saliva causin
g
bactericidal or bacteriostatic e
ff
ects on various
microorganisms requiring iron
f
or their survival
s
uc
h
as t
h
e
Streptococcus mutans
group.
s
L
acto
f
errin also provides
f
un
g
icidal, antiviral,
a
nti-in
f
lammator
y
, and immunomodulator
y
f
unctions
.
3
,
4
,
8
,22,
3
0
Peroxidase or sialoperoxidase o
ff
ers antimicrobial
a
ctivit
y
because it serves as a catal
y
st
f
or the
oxidation o
f
the salivar
y
thioc
y
anate ion b
y
h
y
d
rogen peroxi
d
e into
h
ypot
h
iocyanate, a
potent antibacterial substance. As a result o
f
its
consumption, proteins an
d
cells are protecte
d
f
rom the toxic and oxidant e
ff
ects o
f
hydrogen
peroxi
d
e
.
3
,
4
,
8
,22
T
h
e proline-ric
h
proteins an
d
stat
h
erins in
h
i
b
it t
h
e
s
pontaneous precipitation o
f
calcium phosphate
s
alts and the
g
rowth o
f
hydroxyapatite crystals
on the tooth sur
f
ace, preventing the
f
ormation
o
f
salivar
y
and dental calculus. The
y
f
avor oral
6
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
s
aliva in the
f
loor o
f
the mouth between
s
wallow
s
.
S
ome researchers observed a small increase
in
S
F in the face of visual stimuli
,
while others
ob
s
erved no e
ff
ect whatever
.
9
Regular Stimulation of Salivary Flow
A
lt
h
oug
h
t
h
ere is evi
d
ence regular stimulation
of
S
F with the use of chewin
g
g
um leads to
a
n increase in stimulated
S
F
,
further studies
a
re require
d
to explain w
h
et
h
er t
h
is stimulation
increases unstimulated
S
F
.
9
Size of Salivary Glands and Body Weight
S
timulated
S
F is directl
y
related to the size of the
s
alivary
g
land, contrary to unstimulated
S
F which
d
oes not
d
epen
d
on its size
.
9
U
nstimulated
S
F appears to be independent of
b
o
d
y weig
h
t;
10
on t
h
e ot
h
er
h
an
d
, o
b
ese
b
o
y
s
present si
g
ni
f
icantly lower salivary amylase
concentration in comparison wit
h
controls
.
44
Salivary Flow Index
The main
f
actor a
ff
ectin
g
salivary composition
i
s
the
f
low inde
x
8
,
9
w
h
ic
h
varie
s
in accor
d
ance
w
ith the t
y
pe, intensit
y
, and duration o
f
t
h
e stimulus
.
5,
12
,
1
7
As the
S
F increases
,
the
concentrations o
f
total protein, sodium, calcium,
c
h
lori
d
e, an
d
b
icar
b
onate as well as t
h
e pH
increases to various levels
,
w
h
ereas t
h
e
concentrations o
f
inorganic phosphate and
ma
g
nesium
d
iminis
h.
3,8
Mec
h
anical or c
h
emical
s
timulu
s
i
s
a
ss
ociate
d
w
ith increased salivar
y
secretion. The action o
f
chewin
g
somethin
g
tasteless itsel
f
stimulates
s
alivation
b
ut to a lesser
d
egree t
h
an t
h
e tasty
s
timulation cause
d
by
citric aci
d.
9
Aci
d
su
b
stances
a
re consi
d
ere
d
potent
g
ustatory stimuli
.
10
Contributions of Different Salivary Glands
O
ther factors that influence total salivar
y
composition are the relative contribution o
f
the di
ff
erent salivary
g
lands and the type o
f
s
ecret
i
on
.
5
,
9
The percenta
g
e o
f
contribution by the
glands during unstimulated
S
F is as follows:
20%
b
y t
h
e paroti
d
g
lan
d
s
65%-70% su
b
man
d
i
b
ular
g
lan
d
s
7% to 8% su
b
lingual glan
d
s
<10%
b
y t
h
e minor salivary
g
lan
d
s
W
hen
S
F is stimulated
,
there is an alteration in
the percenta
g
e o
f
contribution o
f
each
g
land with
t
h
e salivary glan
d
s cease secretion to conserve
w
a
te
r
.
3
7
Body Posture, Lighting, and Smoking
S
F varies in accordance with body posture, li
g
htin
g
con
d
itions, an
d
smokin
g
. Patients kept stan
d
in
g
u
p or lying down present higher and lower
S
F,
r
espectivel
y
, t
h
an seate
d
patients. T
h
ere is a
decrease of 30% to 40% in
S
F of people that are
blind
f
olded or in the dark. However
,
the
f
low is not
l
ess in
b
lin
d
people, w
h
en compare
d
wit
h
people
w
it
h
normal vision. T
h
is su
gg
ests t
h
at
b
lin
d
people
a
dapt to the lack o
f
light that enters through the
eyes. Olfactive stimulation and smokin
g
cause
a
temporar
y
increase in unstimulated
S
F
.
9
M
e
n
that smoke present signi
f
icantly higher stimulated
S
F than non-smokin
g
men
.
38
The irritatin
g
e
ff
ect
o
f
tobacco increases
g
landular excretion
,
3
9
an
d
nicotine causes severe morphologic and
f
unctional
a
lterations in t
h
e salivary
g
lan
d
s
.
4
0
The Circadian and Circannual Cycle
S
F attains its peak at the end of the afternoon
b
ut
g
oes
d
own to almost zero
d
urin
g
sleep.
S
alivar
y
composition is not constant and is related
to the Circadian c
y
cle
.
4,
41
Th
e
c
o
nc
e
ntrati
o
n
of
total proteins attains its peak at the end o
f
the
af
ternoon, while the peak production levels o
f
s
odium and chloride occur at the be
g
innin
g
o
f
the
morn
i
n
g.
9
A
ccor
d
in
g
to E
dg
ar
,
9
t
h
e circannual r
hy
t
h
m also
in
f
luences salivar
y
secretion. In the summer lower
volumes o
f
salivary
f
lows
f
rom the parotid gland,
w
hile in the winter there are peak volumes o
f
s
ecretion. However
,
t
h
ese
d
ata were o
b
taine
d
in
the state of Texas in the southern United
S
tates
a
nd the reduction in
S
F ma
y
be associated
w
ith deh
y
dration that occurs because o
f
the hot
we
at
he
r
.
Medications
Many classes o
f
drugs, particularly those that
have anticholiner
g
ic action (antidepressants,
a
nxiol
y
tics, antips
y
c
h
otics, anti
h
istaminics, an
d
a
ntih
y
pertensives), ma
y
cause reduction in
S
F
a
n
d
alter its composition
.
9,
18
,
4
2,
43
Thinking of Food and Visual Stimulation
Thinkin
g
o
f
f
ood or lookin
g
at
f
ood are weak
s
alivation stimuli in
h
umans. It ma
y
seem t
h
at
people salivate simply because o
f
thinking o
f
f
ood,
but in realit
y
the
y
become more conscious o
f
the
7
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
is
h
ig
h.
2
Alterations in t
h
e ps
y
c
h
o-emotional
s
tate ma
y
alter the biochemical composition o
f
s
aliva. Depression is accompanie
d
by
d
iminis
h
e
d
s
alivar
y
proteins
.
48
Nutritional de
f
iciencie
s
ma
y
also in
f
luence salivar
y
f
unction and
compos
i
t
i
on
.
4,
11
Fasting and Nausea
A
lthou
g
h short-term fastin
g
reduces
S
F it does
not lead to h
y
posalivation, and the
f
low is
r
estored to normal values immediatel
y
a
f
ter the
f
astin
g
period ends
.
11
S
timulated
S
F increases
wh
en prece
d
e
d
b
y gustatory stimulation in less
than one hour be
f
ore saliva collection
.
4
9
S
aliva
s
ecretion increases be
f
ore and durin
g
vomitin
g.
9
Age
D
espite numerous stu
d
ies on salivar
y
secretion
the effect of aging on
S
F remains obscure due to
con
f
lictin
g
observations in the literature leavin
g
l
ittle information available re
g
ardin
g
S
F in healthy
el
d
erl
y
persons
.
5
0
H
istolo
g
ic analyses
h
ave
d
emonstrate
d
wit
h
a
dvancing age the parenchyma o
f
the salivary
g
lan
d
s is
g
ra
d
ually replace
d
b
y a
d
ipose an
d
f
ibrovascular tissue
,
and the volume o
f
the acini
i
s
re
d
uce
d.
51,5
2
However,
f
unctional studies among
healthy individuals indicate a
g
in
g
itsel
f
does not
necessarily lea
d
to
d
iminis
h
e
d
g
lan
d
ular capacity
to pro
d
uce saliva
.
19
N
avazes
h
et al
.
5
3
found the total unstimulated
S
F
is signi
f
icantly lower in healthy patients between
the a
g
es o
f
65 and 83 years, in comparison with
patients between the a
g
es o
f
18 and 35 years.
H
owever, total stimulated
S
F was significantly
h
i
gh
er in t
h
e el
d
erly in comparison wit
h
t
h
e
yo
un
g
er pers
o
ns
.
P
e
rcival
e
t al
.
5
0
also
f
ound the total unstimulated
S
F is related to a
g
e, bein
g
si
g
nificantly reduced
in
h
ealt
h
y non-me
d
icate
d
el
d
erly persons age
d
8
0 years or ol
d
er. However, no a
g
e-relate
d
r
eductions in stimulated
S
F from the parotid
w
ere
d
etecte
d
. It is suggeste
d
t
h
e el
d
erly
do not present d
y
s
f
unctions in the abilit
y
to
r
espon
d
to sialo
g
o
g
ues,
h
owever, t
h
e re
d
uction
in unstimulated
S
F could contribute to the
a
ppearance o
f
diseases in the oral mucosa
.
L
ima
e
t al
.
54
d
emonstrate
d
el
d
erl
y
persons
presente
d
a ver
y
low
d
ail
y
saliva pro
d
uction,
the parotids contributin
g
over 50% o
f
the total
s
alivar
y
secretion
.
3,4,11,12,4
5
T
h
e salivar
y
secretions ma
y
b
e serous,
mucous, or mixed.
S
erous secretions, produced
mainl
y
by
t
h
e paroti
d
s, are ric
h
in ions an
d
enz
y
mes. Mucous secretions are ric
h
in mucins
(glycoproteins) and present little or no enzymatic
a
ctivit
y
. T
h
e
y
are pro
d
uce
d
mainl
y
by
t
h
e
s
maller
g
lan
d
s. In t
h
e mixe
d
g
lan
d
s, suc
h
as t
h
e
s
u
b
man
d
i
b
ular an
d
su
b
lingual glan
d
s, t
h
e salivary
content
d
epen
d
s on t
h
e proportion
b
etween t
h
e
s
erous an
d
mucous cells
.
2,
8
,
13
,
1
7
Physical Exercise
P
hy
sical exercise can alter secretion an
d
in
d
uces
c
h
anges in various salivary components, suc
h
a
s: immuno
g
lo
b
ulins,
h
ormones, lactate, proteins,
a
n
d
electrol
y
tes
.
4
6
,
47
In a
dd
iti
o
n t
o
t
he
de
t
e
rmin
ed
intensit
y
o
f
the exercise, there is a clear rise
in salivar
y
levels o
f
α
-amilase an
d
electrol
y
tes
(especiall
y
Na
+
).
46
Durin
g
p
h
ysical activities
s
ympat
h
etic stimulation appears to
b
e strong
enou
gh
to
d
iminis
h
or in
h
i
b
it salivary secretion
.
47
Alcohol
The intake o
f
a sin
g
le hi
g
h dose o
f
ethanol
causes a si
g
ni
f
icant reduction o
f
stimulated
S
F. This diminishment results from the altered
r
elease o
f
total proteins and am
y
lase as well
a
s in diminished release o
f
electrol
y
tes
.
29
Rats
exposed to ethanol
f
or a prolonged period showed
s
i
g
ni
f
icant reduction in salivary secretion and
diminished release o
f
proteins
.
40
Systemic Diseases and Nutrition
In some c
h
ronic
d
iseases suc
h
as: pancreatitis,
diabetes mellitus, renal insu
ff
icienc
y
, anorexia,
b
ulimia, an
d
celiac
d
isease, t
h
e am
y
lase level
8
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
paroti
d
w
h
en compare
d
wit
h
men. W
h
ereas,
S
hern et al
.
57
reported the total unstimulated
S
F
w
as not in
f
luenced by
g
ender
.
Conclusion
S
ince several factors can influence salivar
y
s
ecretion an
d
composition a precise stan
d
ar
d
f
or saliva collection must be established.
S
uch
a
stan
d
ar
d
woul
d
make t
h
e test results o
b
taine
d
t
h
roug
h
sialometry an
d
/or sialoc
h
emistry more
help
f
ul in characterizin
g
the true
f
unctional state
o
f
the salivary
g
lands which in turn would serve
a
s indicators
f
or a diagnosis when oral and/or
sy
stemic alterations are suspecte
d.
Clinical Significance
S
ince man
y
oral and s
y
stemic conditions
mani
f
est themselves as chan
g
es in the
f
low and
composition o
f
saliva the dental practitioner is
ad
vise
d
to remain up-to-
d
ate wit
h
t
h
e current
l
iterature on t
h
e su
bj
ect
.
a
n
d
t
h
is appears to
b
e more relate
d
to s
y
stemic
diseases and the continuous use o
f
medications
t
h
an to a
g
in
g.
Gender
The di
ff
erences in salivar
y
secretion between
m
e
n an
d
w
o
m
e
n
h
av
e
bee
n attri
b
ut
ed
t
o
tw
o
t
h
eories: women present smaller salivar
y
g
lands in comparison with men and the
f
emale
h
ormonal pattern ma
y
contri
b
ute to
d
iminis
h
e
d
s
a
li
var
y
secret
i
on
.
5
0
However, menopause an
d
h
ormone replacement t
h
erap
y
are not associate
d
w
ith salivar
y
d
y
s
f
unction o
f
the parotid
.
55
T
he
r
e
w
ere no si
g
ni
f
icant di
ff
erences with re
g
ard to
S
F between health
y
pre- and post-menopausal
w
omen an
d
b
etween post-menopausal women
u
n
de
r
ho
rm
o
nal tr
e
atm
e
nt an
d
w
o
m
e
n t
h
at
d
i
d
n
o
t r
e
c
ei
v
e
tr
e
atm
e
nt
.
5
6
P
e
rcival
e
t al
.
5
0
f
ound health
y
, non-medicated
w
omen presented a lower mean
f
or total
u
nstimulated
S
F and for stimulated
S
F of the
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About the Authors
11
The Journal of
C
ontemporar
y
Dental Practice, Volume 9, No. 3, March 1, 2008
... A critical step toward generating comparable salivary AD biomarker data across laboratories and studies is establishing guidelines and a standardized protocol for pre-analytical variables, mirroring the fruitful initiatives already established for CSF and blood AD biomarkers. [19][20][21][22] Standardization efforts with respect to salivary biomarkers in other fields are ongoing and comparatively well established, 23,24 and although salivary biomarkers have only recently garnered interest in the AD research communities, 25 a standardized protocol for pre-analytical variables for salivary AD biomarker research is important. For example, inconsistent outcomes in the measurements of Aβ42 and Aβ40 have been obtained depending on the sampling methodologies. ...
... Conversely, "resting" whole saliva is mainly produced by the submandibular gland (approximately 72%), while the parotid and sublingual glands produce only 20% and 8% of whole saliva, respectively. 22,23 Regardless of the stimulation method applied, stimulated saliva is mainly derived from the parotid gland 22,24 and results in saliva composed mainly of water. This causes unwanted dilution of analytes, as confirmed by Mohamed et al., who showed that levels of smaller proteins were significantly lower in stimulated saliva samples. ...
Article
Full-text available
There is a pressing need for accessible biomarkers with high diagnostic accuracy for Alzheimer's disease (AD) diagnosis to facilitate widespread screening, particularly in underserved groups. Saliva is an emerging specimen for measuring AD biomarkers, with distinct contexts of use that could complement blood and cerebrospinal fluid and detect various analytes. An interdisciplinary, international group of AD and related dementias (ADRD) researchers convened and performed a narrative review of published studies on salivary AD biomarkers. We critically appraised the current state of the literature, examining both consistencies and discrepancies in existing pre‐analytical variables and methodologies. We discussed how various pre‐analytical variables could influence the detection and quantification of salivary biomarkers, showed technologies available to standardize collection procedures, and proposed a standardized pre‐analytical protocol to guide future studies on salivary AD biomarker examinations. We identified potential contexts of use, gaps, and priorities and proposed future research directions. Highlights Given its non‐invasive nature, wider accessibility, and cultural acceptability, particularly in low‐resourced settings, saliva is a biofluid complementary to blood and CSF. Current salivary AD biomarker studies do not control for many confounding pre‐analytical variables during the sampling process, potentially leading to inaccurate salivary biomarker readings and conclusions, contributing to conflicting findings. Reviewing the current literature, including the consistencies and non‐consistencies observed in the existing parameters and methodologies, discussing how they can affect salivary AD biomarker detection and quantification. Proposing a standardized salivary pre‐analytical protocol, identifying the gaps and prioritizations needed to move this area forward, proposing future directions and potential contexts of use.
... Reduction of Dental Hypersensitivity: Saliva coats the tooth surface, helping reduce dental hypersensitivity. When dentin is exposed, saliva forms a protective barrier around sensitive areas, reducing the pain caused by thermal or tactile stimuli [22,43]. ...
... dental hypersensitivity. When dentin is exposed, saliva forms a protective barrier around sensitive areas, reducing the pain caused by thermal or tactile stimuli [22,43]. ...
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Full-text available
Saliva plays a multifaceted role in oral health and systemic well-being. It supports digestion, protects oral tissues, maintains a healthy oral microbiome, and facilitates wound healing. Additionally, saliva serves as a diagnostic tool that reflects systemic health and disease/therapeutic states. Furthermore, although saliva shows a protective effect against oral cancer development, once tumor formation occurs, it may be involved in tumor progression and metastasis via exosomes and microRNAs. This review discusses the essential role of saliva; its relationship with the development, progression, and metastasis of head and neck squamous cell carcinoma (HNSCC); liquid biopsy tools for early diagnosis and monitoring of HNSCC; and the potential of exosomes as therapeutic agents.
... For instance, stimulated saliva often has higher concentrations of bicarbonate, enhancing its buffering capacity to neutralize acids during food intake. Additionally, the protein concentration and enzymatic activity can vary between stimulated and unstimulated saliva, influencing its protective functions [27]. In pediatric populations, these differences are pertinent when assessing salivary function and its role in oral health. ...
Article
Full-text available
Dental caries is one of the most prevalent chronic conditions among children globally. Salivary pH monitoring, an essential diagnostic parameter, plays a critical role in understanding caries risk and oral health. This scoping review aims to evaluate the application of digital salivary pH meters in pediatric dentistry, particularly in caries diagnosis and prevention, while exploring the potential integration of artificial intelligence (AI) in this domain. Methods: A literature search was conducted across the PubMed, Web of Science, and Scopus databases for studies published between 2014 and 2024. The inclusion criteria focused on clinical studies involving children aged 1 to 18 years and the use of digital salivary pH meters. Studies that utilized AI in conjunction with salivary pH monitoring were also reviewed. Data were extracted and analyzed to assess the effectiveness of pH meters in caries detection and their role in broader oral health applications. Results: Out of 549 articles screened, 11 met the inclusion criteria. The review highlighted the utility of digital pH meters for assessing caries risk, monitoring dietary impacts, and evaluating the effectiveness of preventive treatments. However, none of the studies combined salivary pH monitoring with AI. Emerging technologies, such as smartphone-based pH sensors, have demonstrated promising applications for real-time, non-invasive diagnostics. Conclusions: Digital salivary pH meters provide precise and reproducible measurements, significantly enhancing caries risk assessment and preventive strategies in pediatric dentistry. While AI integration remains unexplored in this context, its potential to refine risk prediction models and personalize treatments underscores the need for future research in this area. These advancements could improve caries prevention and management, enhancing pediatric oral health outcomes.
... In this study, we found that pSjD patients with higher C3, CFB, and CALR showed significantly impaired uSFR and sSFR, but all five salivary biomarkers were not correlated with ESSDAI scores. As submandibular glands contribute mainly to unstimulated salivary secretions while parotid glands dominate the flow of stimulated secretions [38,39] salivary C3, CFB, and CALR may reflect secretory hypofunction of submandibular glands and parotid glands, indicating that they may hold promise for assessing disease activity and treatment efficacy. Interestingly, C3 and CFB were both involved in complement systems, suggesting complement activation might play pathogenetic roles in salivary gland injury. ...
Article
Full-text available
Background Minor salivary gland (MSG) biopsy is a critical but invasive method for the classification of primary Sjögren’s disease (pSjD). Here we aimed to identify salivary proteins as potential biomarkers and to establish a non-invasive prediction model for pSjD. Methods Liquid chromatography-tandem mass spectrometry was conducted on whole saliva samples from patients with pSjD and non-Sjögren control subjects (non-pSjD). Proteins involved in immune processes were upregulated in the pSjD group, such as complement C3 (C3), complement factor B (CFB), clusterin (CLU), calreticulin (CALR), and neutrophil elastase (NE), which were further confirmed by ELISA. Multivariate logistic regression analyses were performed to identify markers that differentiated pSjD from non-pSjD; receiver operating characteristic (ROC) curves were constructed. A diagnostic model based on the combination of salivary biomarkers (CFB, CLU, and NE), serum autoantibodies (anti-SSA /Ro60 and anti-SSA/Ro52), and Schirmer’s test was evaluated in 186 patients (derivation cohort) with replication in 72 patients (validation cohort). Results In multivariate analyses, CFB, CLU, and NE were independent predictors of pSS. A model based on the combination of salivary biomarkers (CFB, CLU, and NE), serum autoantibodies (anti-SSA and anti-Ro52), and Schirmer’s test achieved significant discrimination of pSS. In the derivation cohort, the area under curve (AUC) of the ROC was 0.930 (95% CI 0.877–0.965, P < 0.001), with a sensitivity and specificity of 84.85% and 92.45%, respectively. Notably, similar results were obtained in a validation cohort. Conclusion The 6-biomarker panel could provide a novel non-invasive tool for the classification of pSjD.
... Saliva comprises proteins that are synthesized in the salivary glands or derived from gingival crevicular fluid, serum transudate, epithelial cells, leukocytes, and microorganisms. 30 As part of the endocrine system, many constituents enter saliva from blood via passive diffusion or active transport. 31 Comprehensive analysis of the salivary contents is essential for understanding disease states and identifying potential biomarkers. ...
Article
Full-text available
Early childhood caries (ECC) significantly impacts the physical and mental health of children. Saliva stands as a critical model for investigating the pathogenesis of caries disease since it reflects both host and microbial dynamics. However, the specific contributions of salivary host factors to ECC have not been fully understood. In this study, we monitored a prospective cohort of 3–4 year-old healthy children for 12 months, who either stayed caries-free or developed caries. Deep quantitative proteomics analysis of saliva was conducted at both recruitment and end point of the cohort to investigate the molecular mechanisms underlying ECC etiology and identify potential biomarkers for caries prediction. Proteomics analysis identified a total of 2873 proteins and revealed involvement of immune response, dental structure repair, and regeneration, as well as interactions with microorganisms during caries pathogenesis. Characteristic salivary proteins were identified in caries-susceptible children prior to caries development. An ECC prediction panel of proteins keratin 3 (KRT3) and mucin 21 (MUC21) was established and further validated through another independent cohort. This study illuminated the role of the complex salivary microenvironment in caries etiology and offered a prognostic tool for early ECC prediction, thus facilitating the precise prevention and control of ECC to ultimately reduce its incidence.
... In this sense, substrates synthesized on the basis of colloidal silver or gold nanoparticles are a highly used class in biofluid analysis. The spectra recorded with these plasmon substrates can be used to develop new diagnostic strategies for various diseases belonging to the broader class of liquid biopsy methods [10][11][12]. ...
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Full-text available
The use of Raman spectroscopy, particularly surface-enhanced Raman spectroscopy (SERS), offers a powerful tool for analyzing biochemical changes in biofluids. This study aims to assess the modifications occurring in saliva collected from patients before and after exposure to cone beam computed tomography (CBCT) and computed tomography (CT) imaging. SERS analysis revealed significantly amplified spectra in post-imaging samples compared to pre-imaging samples, with pronounced intensification of thiocyanate and opiorphin bands, which, together with proteins, dominated the spectra. The changes were more pronounced in the case of CT as compared to CBCT, probably due to the use of a high radiation dose in the case of the first-mentioned technique. These findings underscore the impact of CBCT and CT on salivary composition, highlighting the relevance of SERS as a sensitive method for detecting subtle molecular changes in biofluids post-radiation exposure. This study’s results emphasize the importance of monitoring biochemical markers in patients undergoing diagnostic imaging to better understand the systemic effects of ionizing radiation.
Article
Full-text available
Objectives: The aim of this study was to examine the association between medication exposure and (1) unstimulated whole-salivary flow rate and (2) the severity of xerostomia among older people while adjusting for multiple medication use. Methods: Data were obtained from participants remaining at the five-year follow-up phase of a cohort study of community-dwelling older South Australians. Medication exposure information was available at baseline and at five years, enabling examination of the effects on dry mouth of long-term exposure to medications. At the five-year follow-up, unstimulated salivary flow was estimated using the spit method, and xerostomia severity was estimated using the 11-item Xerostomia Inventory. Because of the potential difficulties posed by polypharmacy, a two-stage analytical approach was employed: (1) Classification and Regression Tree (CART) analysis was used as an exploratory device to elucidate the relationships among the dependent and independent variables, and (2) linear regression analysis was used as a complementary procedure. Results: Unstimulated flow rate was lower among individuals who were female or taking antidepressants at both baseline and five years, and higher among smokers or people who were taking hypolipidemic drugs. Xerostomia severity was higher among females, or individuals taking: (1) an anginal at baseline and five years, (2) an anginal without a concomitant betablocker at five years, (3) thyroxine and a diuretic at five years, or (4) antidepressants or antiasthma drugs at both baseline and at five years. Conclusions: These results suggest that polypharmacy can be accounted for to a certain extent by using CART analysis in conjunction with more conventional approaches; and that the relationship between medications and dry mouth is a complex one, and differs according to which aspect of dry mouth is being examined.
Article
Full-text available
Article
Xerostomia, or dry mouth, is a serious oral health problem that, when left untreated, leads to deterioration and disease in the oral cavity. Patients with dry mouth include those on xerogenic medications (including many elderly patients), those undergoing chemotherapy and radiation, and individuals with Sjögren syndrome, an autoimmune disease. Common complaints with dry mouth include difficulty in speaking, chewing, and tasting and swallowing foods. Patients with dry mouth will also complain of food sticking to the teeth, taste alterations, foods burning the oral tissues, and a burning tongue. The lack of saliva may lead to such complications as fungal infections (eg, candidiasis), atrophy of the filiform papillae of the tongue, mucosal ulcerations, salivary gland enlargement, an increase in the number of cariogenic, aerobic organisms Streptococcus and Lactobacillus, and rapidly progressing caries. Recommended therapy for patients with xerostomia includes regular dental visits, fluoride therapy, nutritional counseling, and patient education regarding oral home care to manage the high risk for dental decay. Some patients may also benefit from the use of artificial salivas or Pilocarpine, which is effective in increasing salivary flow in patients with functional salivary glands. Salivary stimulants and increased water intake are also recommended.