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CLINICALFEATURE
renal and arrhythmia risks. Future safety monitoring is
warranted and may benefit from an active and continuous
cumulative surveillance system. (Zhang et al 2006)
Opoids are agent that binds to opioid receptors, found
principally in the central nervous system and gastrointestinal
tract. There arefour broad classes of opioids:
1. endogenous opioid peptides, produced in the body; (eg
endorphins)
2. opium alkaloids, such as morphine (the prototypical opioid)
and codeine;
3. semi-synthetic opioids such as heroin and oxycodone
4. fully synthetic opioids such as pethidine and Fentanyl;
Tramadol that have structures unrelated to the opium
alkaloids (Fentanyl)
The non-clinical use and off-label clinical use were criminalized in
the USA by the Harrison Narcotics Tax Act of 1914, and by other
laws worldwide. In USA, the Controlled Substances Act of 1970
markedly relaxed the harshness of the Harrison Act. Opoids act
on the following opioid receptors in the nervous system:
Pharmaco Sci 1993) The common steroids used in dentistry
are Dexamethasone and Prednisolone.
Enzymes for anti inflammatory are a naturally occuring
protease enzyme that digests non-living tissue, blood clots,
cysts, and inflammation in all forms. The common ones are:
1. Serrapeptidase: It acts via the hydrolysis of peptides into
amino acids. It is a powerful proteolytic enzyme obtained
from silkworms
2. Papain: It is also known ascysteine protease (EC 3.4.22.2)
and ispresent in papaya (Carica papaya) which is useful in
tenderizing meat and other proteins.
The exact mode of Action is unknown. However, preliminary
studies show some potential in inflammation reduction. It is
concluded that Serratia peptidase has anti-inflammatory, antioedemic
and fibrinolytic activity and acts rapidly on localized
inflammation. (Mazzone A et al, 1990 J Int Med Res)
Finally, here is a diagram of the inflammatory process and the
action of drugs used in dentistry for pain management.
1. MU
2. Delta (still in discussion)
3. Kappa
4. Sigma-
5. Epsilon (still in discussion)
Common adverse reactions include: tolerance, dependence
and withdrawal issues, nausea and vomitting, drowsiness,
dizziness, headache, orthostatic hypotension, itch, dry mouth,
miosis, urinary retention, and constipation. (Rossi, 2005).
Tolerance can be detected within 12-24 hours of the
administration of morphine (Rang et al, 2003) and results in the
necessity for increasing the dose over time to achieve the
desired clinical effect. It appears to develop first to the
analgesic, sedative, emetic, euphoric and respiratory
depressive effects of opioids. The miotic and constipating
effects are more resistant to the development of tolerance.
(Rang et al, 2003)
For anti-inflammatory drugs, the following are used:
1. Steriods
2. Enzymes, eg Serro-peptidase
3. NSAIDs (as discussed earlier)
Steriods are terpenoid lipid characterized by a carbon skeleton
with four fused rings. All steroids, being terpenoids, are derived
from HMG-CoA which itself is derived from the acetyl CoA
biosynthetic pathway. For anti-inflammtory, these are usually
Glucocorticoids. The mode of action is (Anti-inflammatory
mechanism) by decreasing gene transcription of cytopkines,
chemokines, inflammtory enzymes, decreasing T/B cells,
macrophages,direct vasoconstriction. (Barnes PJ Trends
Legends
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Confirmed mode of action
Associated mode of action
Dr Bertrand Chew has a Masters in Oral and
Maxillofacial Surgery and is a Fellow of the Royal
Australian College of Dental Surgeons. Currently,
he is working with the Singapore Armed Forces as
an Oral Maxillofacial Surgeon. He also lectures on
the FDI Asia-Pacific circuit and is active with the
Singapore Dental Association.
42 Dental Asia • May / June 2008