Module 2_Basic Lab Techniques_Suturing

Question 1

What instruments are used for suturing?

Answer 1

Scalpel with size 15 blade
Tooth tissue holding forceps (shape is similar to tweezers)
Artery forceps
Scissors
Periosteal elevator
Malleable Retractor
Suture (has needle curved need at the end which are round or triangular in cross section

Question 2

What types of sutures are there?

Answer 2

• Non-resorbable commonly used (silk or nylon)

- However resorbable often used when buried in tissue or removal difficult (gut or polyglycolic)

Question 3

How do you do a suture?

Answer 3

1. Make cut in the cheek (stretch it and cut towards yourself)–>only done so you have a wound to suture for practice, not actually done in clinic
2. Grasp the tissue with tooth tissue holders
3. Grasping the needle with the artery forceps pass it through one side of the wound until there is 3-5cm remaining on that side
4. Grab the other side of the wound with the artery forceps and pass the needle through it
5. Tie the suture off
6. Cut off the suture above the knot

Question 4

What dimensions should you achieve with the suture once it has been placed?
(Distance from wound to side of suture (lateral dimension) vs distance from wound to bottom of suture (vertical dimension))

Answer 4

• Distance of wound to bottom of suture should be longer
• Allows the ends of the suture to be pulled together to form a raised area which will flatten out once it contracts (think tectonic plates pushing together to form a mountain)

Question 5

What happens if vertical dimension of suture shorter than lateral dimension?

Answer 5

Once wound contracts will cause a pit

Question 6

What happens if you put the suture through both sides at the same time?

Answer 6

-It will be asymetrical and cause one side to be higher than the other creating a step

Question 7

How do you create a long wound? (Taller mountain) What is the technique called? When would you use it?

Answer 7

Pass the suture once
Don’t tie it off
Pass it through underneath again but ensure it is below the first crossing and tie off

*This technique is called a vertical mattress suture

Use it when want good contact over broad area of tissue (e.g. oral antral fistula where you do not want food to get in there)

Question 8

Where should a suture knot be tied and why?

Answer 8

• On the side (as if in the middle then food trapped in the knot can irritate the wound)
• As far from the tongue as possible (tongue can undo the knot)

Question 9

What kind of knots are possible with sutures and how do you do them?

Answer 9

Surgeon’s knot

1. Grab the side of the suture from the first end of the wound with the artery forceps (the side where you left 3-5cm)
2. Wrap the other end of the suture twice around the artery forceps
3. Slide the suture off the forceps (effectively tying a regular knot)
4. Grab the first end again, wrap the second end around the artery forceps once but in the opposite direction and slide off again
5. Repeat step 4. again but in the opposite direction (so same direction as when you started)
6. Cut off the suture just above the knot

Sliding knot

1. Grab the first end of the suture with the artery forceps
2. Wrap the second end of the suture around the artery forceps once around and slide down loosely
3. Wrap the second end of the suture around the artery forceps again in the same direction and slide it down loosely (so you end up with a double knot i.e. a clave hitch)
4. Slide the knot down to final position
5. Do a final knot by wrapping the suture around the artery forceps once in the reverse direction and slide off so suture won’t come undone
6. Cut off the suture just above the knot

*Cut off sutures about 3-4mm from the knot

Question 10

What happens if you cut off a knot too high?

Answer 10

-More likely to get undone

Question 11

What happens if you cut off a knot too low?

Answer 11

-More likely to irritate the wound