SUTURING MATERIALS

AND TECHNIQUES

MADE BY:

Akshat SachdevaBDS Final YearManav Rachna Dental College

INTRODUCTION

The purpose of a suture is to hold tissues in apposition until the wound has healed sufficiently to be self – supportive.

Sutures function primarily to maintain wound closure and to promote wound healing during the time when the wound is most vulnerable.

Wound healing process can be affected by the amount of suture material used, suture type, suturing technique and the amount of tension in the suture.

SUTURE MATERIAL

Features of an ideal suture material include:

• Should have high tensile strength to hold the wound margins appropriately till healing is complete.

• Should not be allergic or cause any tissue inflammation.• Should have least capillarity so that the material does not soak up

much of the inflamed tissue fluid surrounding the wound and further exaggerate infection.

• Should have good knotting properties.• Should be easily sterilized.• Should be visible in the surgical field.• Should be inexpensive.

CLASSIFICATION

Sutures are classified into two groups:1. Absorbable: These materials lose their tensile strength within 60 days.

They are digested by the enzymes inside the body.• Natural.• Synthetic.2. Non – Absorbable: Cannot be digested by the body and should be removed by the surgeon at the end of healing.• Natural.• Synthetic.• Metallic.

Sutures can also be classified into monofilament and multifilament.I. Monofilament: Consists of single strand of suture material.II. Multifilament: Consists of several filaments twisted or braided

together.

Suture material Absorbable Non – Absorbable

Monofilament Surgical gut plain chromic Polyamide Collagen plain chromic Polypropylene Monocryl Stainless steel PDS II Polyester

Polyglactin 910

Multifilament Polyglycolic Acid Surgical silk Polyglactin 910 Surgical lenin Polyglactin 910 – rapid Cotton

Polyamide braided Polyester braided

Polyester braided coated Stainless steel

ABSORBABLE SUTURE MATERIALS

Natural Absorbable Materials:

1. Catgut:• Also called surgical gut, derived from cattle intima.• Poor tensile strength and high tissue reactivity.• Gut soaked in chromic acid salts will have reduction in tissue

reactivity as compared to untreated catgut.

2. Collagen:• Made by extruding homogenized tendon Achillies of beef cattle and

are almost 100% pure collagen.• Made in plain and chromic form.• Stiffer than surgical gut.• Not in common use.

3. Cartilage Membrane:• Thin sheet of tissue obtained from submucous layer of caecum of ox.• Used to prevent adhesions in abdominal surgery, for isolating ligations

and for covering for packing material in submucous resections.• Permits easy withdrawal of packing after the danger of hemorrhage is

passed.

Synthetic Absorbable Materials:

1. Polyglycolic Acid (Dexon):• First synthetic absorbable suture to become available.• Renowned for its superb tensile and knot strengths in addition to having delayed

absorption and diminished tissue reactivity.• Less of inflammatory response due to absorption of polyglycolic acid by hydrolysis.

2. Polyglactic Acid (Vicryl):• Copolymer of lactide and glycolide, manufactured with a coating of polyglactin 370

and calcium stearate.• Lubricant coating provides Vicryl with its superb handling and smooth tie down

properties.• Degraded by hydrolysis like all synthetic polyesters and thus causes minimal tissue

reaction.

3. Polydioxanone (PDS):• Polymer made from paradioxanone, has prolonged tensile strength.• Hydrolyzed more slowly than other synthetic absorbables; complete

absorption occurs abou 180 days after implantation.• Foreign body reactions found to be minimal.

4. Polytrimethylene Carbonate (Maxon):• Newest absorbable material.• Developed to combine excellent tensile strength retention qualities of

PDS with improved handling properties.• Provides wound support over extended period of time.

Natural Non – Absorbable Suture Materials:

1. Silk:• Created from natural protein filaments spun by the silkworm larva.• Silk is braided, soft and easiest suture material to handle and tie.• Lowest tensile strength.• Elicits more inflammatory reaction, should be avoided in areas prone

to infection.• In cutaneous surgery can be used around eyelids and lips where it lies

flat, causes minimal irritation and has low potential for infection.

2. Linen:• Made from flax and is cellulous material.• Twisted to form a fiber to make a suture.• Material handles the knot well.• Extensively used for tying pedicles and as ligatures.

3. Cotton:• Derived from hairs of seed of cotton plants.• Twisted to form a suture.• Tissue reaction similar to silk and tends to be a polymorphonuclear

cellular type.• Handling good but not so good as silk.• Weaker as compared to linen.

Synthetic Non – Absorbable Suture Material:

1. Nylon:• Most widely used non – absorbable suture in cutaneous surgery as

monofilament.• High tensile strength, excellent elastic properties, minimal tissue

reactivity and low cost.• Main disadvantage is its prominent memory which leads to an

increased number of know throws to hold a given stitch in place.• Multifilamentous braided nylon suture are seldom used because of

higher infection rate and increased cost.• Encounters partial degradation through hydrolysis at very slow rate.

2. Polypropylene (Prolene, Surgilene):

• It is a plastic suture formed from the polymerization of propylene by means of a catalyst.

• Prolene is an extremely inert suture because its tissue reactivity and tensile strength.

• It has a very slippery surface with low adherence to tissue. • Can extend upto 30% before breaking and hence is useful in

situations, when swelling occurs, this suture stretches to compensate for the wound and thus results in less trauma to the sutured tissue.

• When wound swelling recedes, the suture remains loose.

3. Braided Polyesters (Ethibond, Dacron, Ethiflex):

• These are polymers formed by condensation polymerization.

• Manufactured to provide as high tensile strength and low tissue reactivity as the monofilaments along with improved handling and knot security.

• Polyester sutures are either coated or uncoated. • They are not commonly used owing to relatively higher cost.

• Ethibond is an excellent skin suture because of its high knot security in mobile facial areas,

4. Polybutester (Novafil):

• This is the newest of the non absorbable sutures and is a thermoplastic copolymer.

• Monofilamentous suture designed to be stronger and less stiff.

• Its unique feature is its elasticity, as this suture has the capacity to stretch 50% of its length at loads of only 25% of its knot-breaking level.

• This elasticity at low loads has the clinical advantages of elongation of

suture when wound edema occurs and maintenance of tension when the edema recedes. This characteristic reduces the incidence of suture marks and suture cut-throughs.

SUTURING NEEDLES

Needles are made of either stainless steel or carbon steel. Two shapes of needles available:i. Straight.ii. Curved.

Straight Needle:

Types:• Round bodied: circular or oblong in cross – section and gradually

tapers to a point.• Cutting: triangular in cross – section and are sharp enough to finely

pass through keratinized mucosa.

Uses:• For closure of thoracic, iliac or abdominal region.• In maxillofacial surgery, needle is used for the passage of

circummandibular or circumzygomatic wires.

Curved Needles:

Usually used for skin and mucous membrane surgery. Curvatures come in various type such as ¼, 3/8, ½ and 5/8.

Types:1. Round bodied.2. Cutting.

PRINCIPLES OF SUTURING

Needle should be grasped with help of needle holders at approximately 3/4th of its distance from the tip of the needle.

Needle should never be held at the suture end as it’s the weakest point of the needle and grasping at this point results in either bending or breakage of the needle.

Needle should pierce the tissue perpendicular to its surface.

Curved needles should be passed through the tissues following the curvature of the needle to prevent tearing of tissues.

Suture should be placed equidistant (2 – 3 mm) from incision line.

When one side of incision line is fixed and other end free, needle should be passed from free to fixed end.

When one side of tissue is thinner than other side, needle should be passed through thinner to thicker side.

When one side is deeper and other side superficial, needle should pass through deeper to superficial side.

Distance from the incision point to the needle penetration should be less than the depth to which the needle penetrates into the tissues.

Suture should not be tied so tightly that it results in blanching of tissues.

Each suture should be placed 3 – 4 mm apart.

The knot should not be placed over the wound margins.

SUTURING METHODS

1. Simple Interrupted Suture:• Most commonly used.• Sutures are placed independently.• Provides great strength.

Advantages:• Selective adjustments of wound edges can be made.• Failure of one stitch does nor prejudice the others.

Disadvantages:• Can lead to suture marks after postoperative edema has occurred.• Strength of thread reduced by upto 50% due to increased no. of knots.

2. Simple Continuous Suture:• Provides rapid secure closure with even distribution of tension along length of

wound preventing excess tightness.• Provides more water tight closure as required by intraoral bone grafting.• Should not be used in areas of already existing tension.

Indications:• Well approximated wounds with minimal tension that have been initially created by

well placed buried sutures.

Advantages:• Quick and has fewer knots.

Disadvantages:• Not possible to free a few sutures at a time. Even when one breaks, entire closure is

affected.

3. Locking Continuous:

• A degree of locking is provided by withdrawing the sutures through its own loop.

• Tissues align themselves perpendicular to the incision.• Prevents continuous tightening of suture as the wound closure

progresses.

4. Mattress Suture:

• Commonly used in region of abdomen or hip.• Useful in closing the wound of iliac and rib bone graft.• Provides more tissue eversion.• Two types: horizontal and vertical mattress.

i. Vertical Mattress Suture:• Placed by first taking a large bite of the tissue from the wound edge and crossing

through the tissue to an equal distance on opposite side of the wound.• Needle is then reversed and returned with a very small bite at the epidermal/dermal

edge in order to closely approximate wound edge.

Advantages:• Decreases dead space and providing increased strength.• Does not interfere with healing as suture runs parallel to blood supply.

Disadvantages:• Fine wound edge approximation is difficult.

ii. Horizontal Mattress Suture:• Used for intraoral bone grafting.• Needle is passed from one edge of incision to other and again from

latter to the first edge.• Procedure is continued till entire length of incision and a knot is then

tied.

Disadvantages:• Blood supply to the flap edge maybe diminished and can cause

necrosis if not used properly.Horizontal Mattress:

5. Figure of Eight Suture:

• Used for closure of extraction sites.• Provides good adaptation of the gingival papilla along the adjacent

teeth.

SUTURE REMOVAL

• Suture is grasped with an instrument and lifted above the epithelial surface.

• Scissors are then passed through one loop and transected close to the surface.

• Suture is then pulled out.

• Skin sutures are usually removed after a period of 7 – 10 days.

• Mucosal sutures are removed between 5 and 7 days.

REFERENCES

1. Textbook of Oral and Maxillofacial Surgery by Dr. Neelima Anil Malik (3rd edition).

2. Textbook of Oral and Maxillofacial Surgery by Dr. S.M. Balaji (2nd edition).

3. Textbook of Surgery for Dental Students by Dr. Sanjay Marwah (1st edition).

THANK YOU!