Why is knowledge of saliva important for
the dentist (and doctor)? Normal state – anatomy, control of secretory processes, biochemistry/
inorganic and organic components, maintenance of oral and dental health
Disease processes, impact of medicines, young and older people
Xerostomia – impact on soft and hard tissues
Quality of life impact
Dental team leader and team education leader
Patient education
Xerostomia in the older patient
Post radiotherapy, targeted at
mandible, but affecting
submandibular gland
Several other causes
Xerostomia – soft
tissues
• Reduced quality of life – a major impact for
most patients.
• Normal everyday functions severely disrupted
• Speech, chewing dry foods, swallowing, oral
clearance, taste perception
• Other mucosae may well be affected if
systemic aetiology
Xerostomia -
Significant additional risk of damaging mucosa
Need to discuss with patient/carer, especially in elderly patients need to maintain full hydration if salivary function adequate to avoid symptoms of dry mouth.
If wearing complete upper prosthesis significant difficulty in maintaining stability – loss of ‘peripheral seal’ by saliva.
Tooth Decay and Erosion
At 5 years: 52% had erosion affecting primary incisors
At 5 years 40% had decayed teeth
NHS Dentistry: ~4% of GDP in UK
Relative susceptibility of teeth to decay – link
to saliva distribution and flow
Courtesy of A Danchaivijitr Courtesy of A Danchaivijitr
Drugs that Produce Xerostomia
ANALGESICS
ANTIARRHYTHMICS
ANTICONVULSANTS
ANTIDEPRESSANTS
ANTIEMETICS
ANTIHISTIMINES
ANTIHYPERTENSIVES
ANTINAUSEANTS
ANTINEOPLASTICS
ANTIPARASITICS
ANTI-PARKINSON’S
ANTIPSYCHOTICS
ANTISPASMODICS
ANXIOLYTICS
APPETITE SUPPRESSANTS
DECONGESTANTS
DIURETICS
EXPECTORANTS
MOI’s
MUSCLE RELAXANTS
SEDATIVES
TRANQUILLISERS
Dietary causes of Enamel
Demineralisation:
Dental Caries and Erosion
Huge threat from acidic and
sugary drinks, sweets
and foods
2010
2.9 billion bags/packets/boxes of sweets sold in 2011 From Tesco, Asda, Morrisons and Sainsbury (1 pppw = 225g per week per person)
5 ltr per person per week
2010
Drinks Relative titratable
acidity pH
Erosive
potential
Grapefruit juice 9.3 3.2 High
Orange juice 4.8 3.8 High
Apple juice 4.5 3.3 High
Schweppes 2.6 2.6 Moderate
Sunpride 2.4 3.7 Moderate
Carbonated orange
drink 2.0 2.9 Moderate
Ribena ‘Toothkind’ 1.0 2.8 Moderate
Cola 0.7 2.5 Moderate
Diet Cola 0.5 2.9 Moderate
Sparking Water 0.1 5.3 Low
Na+
K+
Na+
K+
Na+
K+
Na+
K+ Cl-
Result: Saliva HCO3-, Cl-
Cl- K+
Na+
Connective
Tissue Lumen
Striated Duct Cell Activated
• Cl- / HCO3- Exchanger
HCO3-
Cl-
HCO3-
Modification of primary saliva in the
striated duct
Paradigm of dental enamel mineral preservation
demineralisation remineralisation
Continuous and dynamic processes
Balancing Act
driven by under/supersaturation wrt HAP
Salivary Calcium
Saliva is supersaturated with respect
to hydroxyapatite (enamel)
Ca
Ca
Ca
Ca
Ca
PO4
PO4
PO4
Ca Ca
Ca PO4
PO4
PO4
Ca
PO4 X
Ca10(PO4)6(OH)2
Tooth Solution adjacent to
tooth surface
Statherin: DpSpSEEKFLRRIGRFGYGYGPYQPVPEQPLYPQPYQPQY
QQYTF
N-terminus
Binds hydroxyapatite
Binds Ca 2+ (SXE motif)
Inhibits secondary precipitation
(crystal growth)
Inhibits primary precipitation
(crystal nucleation)
Salivary protein Statherin and the enamel pellicle
'statheropio' meaning 'to stabilise