Basic Surgical Technique

Question 1

basic principles

Answer 1

risk assessment - good planning & medical history
aseptic technique
minimal trauma to hard & soft tissues

Question 2

stages of surgery

Answer 2

anaesthesia -> access -> bone removal as necessary -> tooth division as necessary -> debridement -> suture -> achieve haemostasis -> post op instruction + medication

Question 3

surgical access

Answer 3

wide based incision - circulation
use scalpel in 1 firm continuous stroke
no sharp angles
adequate sized flap
flap reflection should be down to bone + done clearly
minimise trauma to dental papilla
no crushing
keep tissue moist
ensure flap margins & sutures will lie on sound bone
make sure wounds are not closed under tension
aim for healing by primary intention to minimise scarring

Question 4

soft tissue retraction

Answer 4

access to operative field
protection of soft tissue
flap design to facilitate retraction
howarth’s periostea elevator used

Question 5

bone removal and tooth division

Answer 5

electrical straight handpiece (no air) with saline cooled bur
air driven hand pieces can lead to surgical emphysema
round / fissure tungsten carbide burs
protection of soft tissues

Question 6

principles of use of elevators

Answer 6

mechanical advantage
avoid excessive force
support instrument to avoid injury to ptx should it slip
ensure applied force is directed away from major structures i.e. antrum, ID canal, mental nerve
always use elevators under direct vision
never use adjacent tooth as a fulcrum unless it too is to be XLA
discard if blunt or bent
establish effective point of application
careful debridement after use to remove bone fragments

Question 7

uses of elevators

Answer 7

provide point of application for forceps
loosen teeth prior to using forceps
xla of tooth without using forceps
removal of multiple root stumps
removal of retained roots
removal of root apices

Question 8

3 basic actions

Answer 8

wheel & axle
wedge
lever

Question 9

debridement

Answer 9

physical - bone file / handpiece to remove sharp bony edges, mitchell’s trimmer to remove soft tissue debris
irrigation - sterile saline into socket & under flap
suction - aspirate under flap to remove debris, check socket for retained apices etc

Question 10

aims of suturing

Answer 10

reposition tissues
cover bone
prevent wound breakdown
achieve haemostasis
encourage healing by primary intention

Question 11

non absorbable sutures

Answer 11

if extended retention periods are required
must be removed postoperatively
closure of OAF or exposure of canine tooth

Question 12

polyfilament sutures

Answer 12

several filaments twisted together
easier to handle
prone to wicking - oral fluids / bacteria move along length of suture and can result in infection

Question 13

absorbable sutures

Answer 13

holds tissue edges together temporarily
vicryl breakdown via absorption of water into filaments causing polymer to degrade
may mean review but not removal

Question 14

monofilament sutures

Answer 14

single strand
pass easily through tissue
resistant to bacterial colonisation

Question 15

2 types of suture needles

Answer 15

1. curved
2. cross section

Question 16

peri operative haemostasis

Answer 16

LA with vasoconstrictor
artery forceps
diathermy
bone wax

Question 17

post operative haemostasis

Answer 17

pressure
LA infiltration
diathermy
WHVP
surgicel
sutures

Question 18

when is lingual nerve at risk

Answer 18

nerve is above lingual plate in 15-18% of cases
at risk:
incision of flap
raising of buccal and lingual flaps
retraction of flap
bone removal
extraction with forceps

Question 19

when removing 3rd molars what can nerves can be damaged

Answer 19

lingual
inferior alveolar
mylohyoid
buccal

Question 20

aims of periradicular surgery

Answer 20

establish a root seal at apex of tooth or at point of perforation of a lateral perforation
to remove existing infection e.g. curettage, enucleation of cyst, removal of apical part of root which may have infected lateral canals

Question 21

options for flap design

Answer 21

semi-lunar -> reduced access, only good for apical lesions, scarring, dysesthesia, less gingival recession
triangular
rectangular

Question 22

what is used for a retrograde seal in bone and why

Answer 22

zinc oxide-eugenol
- cheap & easy to use
- radiopaque
- bacteriostatic
- sensitive to moisture
- may resorb
- doesn’t promote cementogenesis

Question 23

removal of apex

Answer 23

remove 3mm
minimal angle to allow visualisation
try to keep cut at right angles to root to minimise surface area
allow curettage

Question 24

what is used for retrograde seal in apex and why

Answer 24

mineral trioxide aggregate
- moisture resistant
- promotes cementogenesis
- very good seal
however it is expensive, has long setting time & difficult to use

Question 25

2 options for root end preparation

Answer 25

ultrasonic - cleans canal, creates 3mm prep within canal, removes contaminated root filling
bur - prep usually outwith confines of canal

Question 26

wound closure after periradicular surgery

Answer 26

resorbable or non resorbable sutures 4.0
replace papillae first
then relieving incision

Question 27

post periradicular op

Answer 27

standard post op instruction
review & ROS at 1week
post op radiograph between 1-6wks
further review 3-6mths

Question 28

reasons why periradicular surgery fails

Answer 28

• inadequate seal; extra/bifid root, too little apex removed, seal of incorrect shape, lateral perforation problem, displacement of seal, lateral canals
• inadequate support; periodontal pockets, occlusal overload, excessive root resection
• split roots
• soft tissue defect over apex post op