Dr V.RAMKUMAR

CONSULTANT DENTAL &FACIOMAXILLARY SURGEON

REG NO:4118 –TAMILNADU -INDIA(ASIA)

INTRODUCTION

The primary purpose for suturing -to hold tissue

layers and wound edges in close approximation

until the healing process provides the wound with

sufficient strength to withstand stress without the

need for mechanical support.

Sutures may be used to either assist healing by

first intention or to minimize wound

contamination or to control haemorrhage.

SUTURE MATERIALS

Ideal suture materials have following

properties:

Adequate strength

Good handling and knot tying

characteristics

Sterilizable

Evoke little tissue reaction

Types of suture materials

Absorbable Plain surgical gut (catgut)Chromic catgut Collagen Polyglycolic acid (Dexon)Polyglactin 910 (Vicryl)

Non-absorbable

Silk

Cotton

Nylon

Dacron (Mersilene)

Polypropylene (Prolene)

Stainless steel

Tantalum

Titanium

Natural / Biological

Catgut

Collagen

Silk

Cotton

Linen

Synthetic / Artificial

Polyglycolic acid (Dexon)

Polyglactin 910 (Vicryl)

Nylon

Dacron (Mersilene)

Polypropylene (Prolene)

Stainless steel

Tantalum

Titanium

Monofilament

Catgut

Polypropylene (Prolene)

Polyethylene

Multifilament

Silk

Cotton

Linen

Polyglycolide

Polyester

Polylactide

Braided

Silk

Polyglycolide

Polylactide

Polyester

Polyamide

Twisted

Cotton

Linen

Coated

Polyester

Polyglycolide

Polylactide

Cotton

Linen

Uncoated

Polyamide

Polypropylene

Polyethylene

Catgut

Collagen

ABSORBABLE SUTURE MATERIALS

    degraded in vivo by enzymatic and phagocytic mechanisms and / or hydrolysis and thus over time diminish in strength and disappear from the tissue.

    The speed of absorption of a suture is roughly proportional to the vascularity of the surrounding tissues.

    In general, absorbable sutures are made to be buried in deep subsurface layers of tissues where they will be slowly absorbed over several days while holding the sutured tissues together.

    Examples: •   Plain surgical gut (catgut)

Biologically derived

     Chromic catgut (tanned gut)

Polyglycolic acid (Dexon)

Synthetic

Polyglactin 910 (Vicryl)

• Gut

– Derived from sheep intestinal submucosa or bovine

intestinal serosa

– Smallest tensile strength

– Packaged in isopropyl alcohol as a preservative

(since highly susceptible to enzymatic degradation).

– Absorbed by proteolytic degradation and

phagocytosis. This is accompanied by

considerable inflammation and tissue reaction.

– Plain gut – more difficult to use than other suture

materials as it is stiff and has insecure knot

holding characteristics when wet.

• Chromic gut – is plain gut that has been tanned with a solution of

chromium salts prior to being spun, ground and polished.

Chromium salts act as a cross-linking agent and increase the tensile

strength of the material and its resistance to absorption by the body.

• Advantages of chromic gut over plain gut:

• Slightly increased strength

• Prolonged rate of absorption

• Lesser stimulation of tissue reaction

• Polyglycolic acid and polyglactin 910

– Resorbed by hydrolysis

– Since they are synthetic polymer, they

produce very little tissue reactions.

NON-ABSORBABLE SUTURE MATERIAL

• Primarily used on surface layers .

• Require surgical removal after fulfilling their mission.

• Can be natural or synthetic

• Example – Natural – silk, cotton, linen

Synthetic – Dacron, nylon, polyester

polypropylene

• Silk

Most popular suture material for intraoral use

braided which gives it excellent handling

characteristics

produces a moderate tissue response

does not irritate adjacent mucous membrane

Inexpensive

• Nylon

Braided or monofilament forms

Because of its stiffness, the large knot required

and a tendency to tear through non-keratinized

tissue, nylon is not frequently used intraorally.

NATURAL / SYNTHETIC SUTURE MATERIALS

Natural

• Biologically derived

• Example:

Catgut (plain gut, chromic gut)

Silk (black braided silk)

Cotton

Nylon

Synthetic

– superior tensile strength

– minimal capillary action within the wound

– induces less inflammatory reaction.

– Example: polyglycolic acid sutures, Dacron, nylon,

polyester, polypropylene.

MONOFILAMENT / POLYFILAMENT SUTURE

MATERIALS

Monofilament: contains single strand

– Example : Polyamide, polypropylene, catgut.

Polyfilament: made up of multiple fibres – either braided or

twisted

– Example: polyglycolide, silk, cotton, linen, steel.

• The size of suture material is with reference to its diameter.

• The smallest size that will provide the desired wound tension must be chosen.

• The higher the number, the smaller the suture.

• Sutures are sized such that No3 is the largest and 7-0 is the smallest in general use.

• The more zeroes in the number the smaller the diameter of the strand.

• Sutures of 5-0 or 6-0 are generally used for skin closure in the head and neck, while 3-0 and 4-0 are used intraorally.

INSTRUMENTATION

• Instruments and materials needed during suturing techniques are

as follows:

– A needle holder

– A pair of tissue forceps

– Suturing needles

– Suture material

– A pair of scissors

NEEDLE HOLDERS

– Resemble artery forceps, but it is characterized by the presence of short

and stout beaks with serrated surfaces to prevent the needle from

slipping during the usage. However handles are sufficiently long.

– Ideally the needle is held clamped by the beaks of the needle holder of a

position, nearly two-thirds of the distance from the tip of the needle.

• While the needle is passed through the tissues, the flap is gripped with a

pair of tissue forceps, with the free margin of flap held everted.

SUTURING NEEDLE

• The needle for suturing vary in size, Curvature, profile of

their cutting point.

• Needles are made of either stainless steel or carbon steel.

• Two basic shapes :

Straight

Curved

• Straight needle

tapered configuration (circular / oblong in cross section)

cutting configuration (triangular in cross section)

• Straight cutting needle

• -used for skin closure in places with adequate access, such as

abdominal, thoracic or iliac regions. -In oral and maxillofacial surgery

-used for the passage of circumzygomatic or circummandibular wires.

Curved Needles• used for both skin and mucous membrane surgery • Manufactured with varying curvatures such as 1/4 , 3/8, ½, 5/8 circle.Needles: A - ¼ circle, B - 3/8 circle, C – ½ circle D – ¾ circle, E – straight with curved end F – straight

Needles in cross section

A – Tapered, B – Cutting, C – Reverse cutting

• Tapered or cutting types:

• Cutting needles are further categorized as :

– Conventional – has one of its three cutting edges along the internal

curvature of the needle.

– Reverse cutting – has a flat internal surface.

• Tapered needle is generally used for closing mesenchymal layer

such as muscle /fascia that are soft & easily penetrable.

• Cutting needle – is used for keratinized

mucosa, skin or subcuticular layers

where the tissue is difficult to penetrate.

• The cutting edge needle make a lateral

cut as it is perforating. It makes suturing

easier through ligamentous tissue.

Needles also vary in their attachment for the suture material

In swaged needle the suture material is inserted into the hollow

end during manufacture and metal is compressed around it. The

needle is not reusable. It is atraumatic.

Eyed needle is designed to be reused and suture material is tied to

the needle. These produce slightly larger holes in the tissue.

PRINCIPLES OF SUTURING TECHNIQUES

• The needle holder should grasp the needle at approximately ¾ of

the distance from the needle tip.

• The needle should enter the tissue perpendicular to the surface.

• The needle should be passed through the tissue following the curve

of the needle.

• The suture should be placed at an equal distance (2 to 3 mm)

from the incision on both sides and at an equal depth.

• It one tissue side is free (as with a flap) and the other fixed the

needle should be passed from the free to the fixed side.

• If one tissue side is thinner than the other then the needle should

be passed from the thinner to the thicker side.

• The distance that the needle is passed into the tissue should be

greater than the distance from the tissue edge. This will ensure

a degree of tissue eversion. Some degree of tissue eversion is

desirable in anticipation of scar contracture.

• The tissues should not be closed under tension, since they will

either tear or necrose around the suture. If tension is present

the tissue layer should be undermined to relieve it.

• The suture should be tied so that tissue is merely approximated not

blanched.

• The knot should not be placed over the incision line.

• Sutures should be placed approximately 3 to 4 mm apart. The

closeness of the sutures depends on the anticipated tension across the

suture line. Closer spaced sutures are indicated in areas of

underlying muscular activity such as the tongue or in other areas of

increased tension.

SUTURING TECHNIQUES Interrupted sutures

Continuous sutures

Mattress sutures

Horizontal

Vertical

Locking continuous suture

Figure of 8

Factors that determine the type of suture are:

• type of the tissue

• condition of the wound

• healing process

• anticipated post operative course.

INTERRUPTED SUTURES

• Most commonly used

• Each suture is independent of the next

offering strength and flexibility in placement.

Simple interrupted suture

• Advantage:

• It is strong

• Successive sutures can be placed in a manner to fit the

individual requirements of the situation.

• The integrity of the suture remains intact even if one suture

is disturbed or lost.

• Only Disadvantage – is the time required when compared to

other techniques.

• Needle enters the mucous membrane from the external to the

tissue surface of the mobile flap.

• Then needle passes from the tissue surface through the fixed

flap and comes out on the surface. Hence both the points of

entry and exit are on the outer surface of the flaps respectively.

• Both these points should be equidistant from free margins of

the flaps.

• Both the ends of the suture materials are tied either by hand or

with instruments.

• At the time of tightening the knot wound margins must be everted.

• Tension must be distributed equally.

• The suture material is adjusted in such as way that the knot lie

over the needle puncture point in any one side of the wound and

not on the suture line.

• The suturing is done at regular intervals.

CONTINUOUS SUTURE

• Used to suture a wide area

• It should not be used in areas of existing tension

• Advantage:

– Ease and conserving the time of suturing

– Even distribution of tension over the entire suture line

– Provides a water tight closure of the wound.

Continuous Technique

• Disadvantage :

– If the wound gives way in any one place it disrupts the

entire wound.

• This is very similar to interrupted sutures. But instead of

tying the knot, the needle is passed again through the

mobile flap and the process continued till the entire wound

is sutured. The knot is placed at the end only.

LOCKING CONTINUOUS SUTURE

• 2 Advantages over simple continuous technique :

suture will align itself perpendicularly to the incision

locking feature prevents continuous tightening of the

suture as wound closure progresses.

Continuous locking technique

• Suture is passed perpendicular to incision line and degree of locking

is provided by withdrawing suture through its own loop. This suture

technique is begun and ended identically to continuous technique.

• Care must be exercised not to tighten the individual lock excessively

since this can produce tissue necrosis.

• Locking feature may prevent adjustment of tension over the suture

line as tissue swelling occurs

MATTRESS SUTURE

• Main purpose of mattress suture is to provide

more tissue eversion than occurs with simple

interrupted suture.

• Mattress suture can be horizontal and vertical

type.

• Point of entry and exit are located in the same flap.

• Point of entry is similar to the interrupted suture.

• The needle passes through the mobile flap and then

through the fixed flap. Instead of placing a knot the

needle is passed in the reverse direction from the fixed

flap through the mobile flap so that ultimately needle

returns back near the point of first entry.

• In horizontal mattress type, point of entry

and point of exit are situated equidistant

from the free margins of the mobile flap.

That means wider areas of the flap are

sutured.

Horizontal mattress technique

• In vertical mattress type, point of entry is situated

away from the wound margin deep into the tissues

while the point of exit is near the wound margin.

Both these points are one above the other.

• Horizontal mattress suture if improperly used

compromise blood supply to the flap edge on both

sides of incision causing necrosis and dehiscence.

Vertical mattress technique

FIGURE OF 8 SUTURE

• Used over extraction sites where it provides some

protection to the surgical area as well as adaptation

of the gingival papillae around the adjacent teeth.

TYPES OF KNOTS

SQUARE KNOT

• Formed by wrapping suture around needle holder once in

opposite directions between ties.

• It is prudent to provide at least 3 ties for surface knots.

• Certain types of suture material such as nylon,

polypropylene, polyglycolic acid, and gut may require more

ties

Square Knot

SURGEON’S KNOT

• Formed by two throws of suture around needle holder on first tie and

then one throw in opposite direction on second tie.

• Because of the double throw, the surgeon’s knot offer the advantage of

reducing slippage of the first tie, while second tie is put in place.

• useful in confined or difficult to reach places where the first tie would

ordinarily be loosened in the process of producing the second tie.

• A third tie squared on the surgeon’s knot is usually made for security.

Surgeon’s knot

GRANNY KNOT

• This knot involves a tie in one direction followed by a single tie

in the same direction as the first.

• This will allow the knot to be slipped to place and provide

initial holding similar to the surgeon’s knot.

• Moreover a 3rd tie squared on the second must be made to hold

the knot permanently.

SUTURE REMOVAL

• Usually the wound margins are cleaned with antiseptics. The

sutures are removed between 5th and 7th post-operative day.

• When sutures are removed, the suture (the knot) should be

grasped with an instrument (forceps) and elevated above the

epithelial surface. A scissors should be used to transect or cut

off one side of the loop as close to the epithelial surface as

possible.

• The portion of suture which is exposed to the outside

environment becomes laden with debris and bacteria.

• So that the minimal portion of this exposed suture to be

dragged through the tissue the loop is cut as close to the

epithelial surface as possible.

• If the suture is cut midway the contaminated external loop is

pulled through the wound that predisposes to wound infection.

A. An intra-oral suture is loose and impregnated with food detritus after being in situ for 1 week.

B. If suture is cut just below the knot as in B the wound is contaminated as infected silk is pulled through the tissues.

C. if the suture is cut just as it enters the tissues the above complication is avoided.