Scope of LA and Supplemental Techniques Flashcards
What is anaesthesia?
Analgesia?
Local anaesthesia?
Anaesthesia: loss of all sensation
Analgesia: loss of pain sensation
Local anaesthesia: a method of anaesthesia that acts in a local (i.e. specific) area of the body and does not result in a loss of consciousness
When was lidocaine synthesised?
When was articaine available in the UK?
What was used prior to lidocaine and articaine?
Lidocaine synthesised in 1943
Articaine available in the UK in 1998
Cocaine was used in the past
What can dental LA be used for?
- pain control: during a procedure and post-operatively
- diagnosis
- haemostasis (due to vasoconstrictor)
What are the main techniques are used for dental LA?
- topical (surface)
- infiltration anaesthesia
- regional anaesthesia
- supplementary techniques
What is topical aneasthesia and list some of its uses?
Anaesthesia of surface tissues
Uses:
- aid to pain free injections
- very minor oral surgery
- abscess incision
- palate for impressions
What is infiltration anaesthesia?
What determines its effectiveness?
Anaesthesia achieved by diffusion of the anaesthestic solution to the site of action and site of operation e.g. the root apex
- effectiveness determined by the permeability of the tissues (especially bone) through which the solution has to pass
What is regional (block) anaesthesia?
What nerves are commonly blocked?
Anaesthesia achieved by blocking a nerve trunk, often at some distance from the site of operation
Nerves commonly blocked:
- Inferior alveolar
- mental and incisive
- lingual
- long buccal
- greater palatine
- naso-palatine
What are the two types of supplemental intra-ossseous anaesthesia?
Intra-osseous - into bone
- intraligamentary/periodontal ligament injection
- direct injection into bone e.g. stabident
Explain the technique of intraligamentary anaesthesia:
What is its likely mode of action?
- high pressure
- low volume
- short needle
Needle between tooth and crestal bone: back pressure, ~0.2ml/root over 20 seconds
- needs a vasoconstrictor, can spread to adjacent teeth –> not a perfect diagnostic tool
Mode of action: spread of solution out of PDL to cancellous bone
What are the advantages of intraligamentary anaesthesia?
Disadvantages?
- low dose (0.2ml per root)
- rapid onset
- little soft tissue anaesthesia
Disadvantages:
- could damage PDL
- post-injection pain
- not always effective
- short/variable duration
- tooth extrusion
- significant bacteraemina - not suitable if endocarditis risk
- technique sensitive
What are the steps of a direct intraosseous anaesthesia?
- Infiltration
- Perforation
- Intraosseous
What is intra-papillary anaesthesia?
- comfortable palatal anaesthesia
- useful for children
- buccal/labial infiltration first
Intrapapillary injection:
- papilla
- slowly advance from buccal to palatal
- inject as needle advances
- palatal blanching
What is an Akinosi injection?
What is an intra-periodontal pocket technique?
High block:
- closed mouth
- needle entry above 7s
- pass back ~2.5 cm
Oraqix
- mixture of 2.5% lidocaine and 2.5% prilocaine
- no needles, do not inject
- thermosets - viscous liquid to a gel in pocket
- useful for RSD
