LA overview Flashcards
what is an additional benefit of LA?
vasoconstrictos in LA aid for haemostatic control for both restorative and surgical procedures
what adverse events can happen when using LA?
systemic toxicity allergy trismus occular complications non-surgical parasthesia interactions methemoglobinemia
what is the definition of pain?
an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage
what can cause dental anxiety?
perception of pain/noxious stimulus
needles
wider societal, environmental and media related pressures
what are the 2 types of LA
ester
amide
which type is safer?
amide
- less reactions
- more predictable
is articain ester or amide?
ester ring
not true ester
what vasoconstrictors are used?
none
adrenaline
felypressin
which vasoconstrictor is most common?
adrenaline
which vasoconstrictor cannot be given to pregnant women?
felypressin
induces labour
which preservatives are used?
bisulphite
propylparaben
what is an infiltration technique?
solution deposited around terminal branches of nerves
used for soft tissues
used to produce pulpal anaesthesia where alveolar bone is thin
maxilla
lower anterior teeth
what is a block technique?
deposited beside nerve trunk abolishes sensation distal to site soft tissue anaesthesia where bone too thick to allow infiltration mandible
what tissues are anaesthetised when restoring?
pulp
soft tissue- matrix/dam
haemostatic management in fixed prosthodontic work -soft tissue
what is anaesthetised when doing extraction/surgical procedures?
pulp, gingiva, surrounding soft tissue
what is anaesthetised when scaling?
gingivae
or
pulp and gingivae
what types of anaesthesia are used in the maxilla?
pulp = buccal infiltration
buccal gingivae= buccal infiltration
palatal gingivae = palatal injection
how is pulp numbed in the mandible?
lower molars & 2nd premolar -ID block lower premolars & canine -mental (incisive) nerve block canines & incisors -buccal/labial infiltration
how is buccal gingivae numbed in the mandible?
molars & 2nd premolar -long buccal infiltration 1st premolar & canine -infiltration/ long buccal/mental block incisors & canines -buccal/labial infiltration
how is lingual gingivae numbed in the mandible?
lingual infiltration
2nd part of IDB
what is the most fragile part of a needle?
the hub
-never insert needle up to hub can cause fracture
what is a bevel?
point of needle
cutting surface to penetrate w/ as little resistance as possible
what is a guage?
diameter of lumen of needle < guage number = > diameter of lumen > guage is better -more accurate -less breakage -easier aspiration
what are the components of a cartridge?
glass tube stopper- punger bung cap diaphragm solution
what do you need for LA?
syringe handle and bung
syringe barrel
cartridge
expiry date & batch
which needle is used for infiltration and which for IDB?
infiltration- short 25mm
block - long 35mm
how should you prepare the equipment for LA?
collect syringe handle and needle collect selected LA cartridge unpack everything record details for decontamination make up syringe handle attach rubber bung -broader end toward handle load cartridge in needle barrel connect syringe handle and LA needle with cartridge -bung end into needle click in place, pull to check prepare needle for use -pull back safety sheath, point away, click sheath into place remove disposable cap by pulling away from needle make needle safe by re-sheathing -1 click re-use, 2 clicks lock
how do you prepare the patient for LA?
check medical history position in chair dry mucosa- guaze/cotton wool apply topical for 1-2 mins -pea size on cotton wool
what is relaxation breathing used for?
reduction of tension
how do you prevent needle anxiety in the px?
keep needle out of view
describe injection technique?
stretch mucosa puncture quickly position needle tip at target point bevel towards bone aspirate inject slowly >30s
what are myths about LA?
needle length influences discomfort
needle diameter influences discomfort
temperature influences discomfort
where is the injection site for buccal infiltration?
reflection of mucosa below apex of tooth
describe infiltration anaesthesia
pulpal anaesthesia limited to 1 or 2 teeth
soft tissue
supra-periosteal
what are limitations of infiltration anaesthesia?
infection may limit effect
dense bone may limit effect
what are positives of infiltration?
high success rate
technically easy
atraumatic
describe buccal infiltration technique?
stretch cheek puncture mucosa with correct bevel of needle - open towards bone advance needle until over apex of tooth if contact bone, withdraw slightly aspirate
what do you do once completed buccal infiltration?
remove syringe from mouth slide sheath down to 1st click replace cartridge if need further injections massage local into tissues wait 2 mins test by sticking probe down PDL
describe palatal infiltration
short needle
penetrate 5-10mm palatal to centre of crown
apply pressure behind injection site
insert needle at 45 angle to injection site w/ bevel angled toward soft tissue
advance needle, slowly deposit as soft tissue is penetrated
advance needle until contact bone
depth of penetration few mm
0.2-0.4ml needed
blanching tissue immediately
describe greater palatine block
posterior portion of hard palate and overlying soft tissues as far as 1st premolar and medially to midline
describe nasopalatine block
anterior portion of hard palate (soft & hard)
bilaterally from mesial of right 1st premolar to mesial of left 1st premolar
how should you dispose of sharps?
take handle off 2 clicks orange box cartridge blue lock bin after use handle sterilised bung clinical waste
what do you avoid in mental nerve block?
foramen
should be between apices of lower premolars
what are the important landmarks for IDB?
coronoid notch of mandibular ramus posterior border of mandible pterygomandibular raphe lower premolar teeth of opposite side site = region of mandibular formamen
where is the thumb placed in IDB?
coronoid notch
where are fingers placed in IDB?
posterior border of mandible
what are the limitations of inferior position?
increased onset time
increased lingual nerve injury
no change in intravascular injection
how many mm above occlusal plane should needle be in IDB?
6-10mm
where is the injection site in IDB?
halfway between coronoid notch and raphe
describe IDB technique
thumb placed at anterior notch
needle entry junction of buccal pad of fat/pterygomandibular raphe
syringe lies over contra lateral 5-6
advance to bony contact, withdraw 1mm
-1mm needle visible
if no bony contact reposition distally
if bony contact too soon, reposition mesially
when in correct position withdraw from bony contact
aspirate
inject slowly
-for lingual anaesthesia withdraw when last 1/3 solution
how do you confirm anaesthesia?
ask px how it feels -rubbery -numb -tingly -swollen/fat IDB tongue & lower lip to midline should feel different ability to sense pressure will remain test mucosa with probe
