By: Granch Berhe2015

MEDICAL TEXTILES Medtech/Medtex

The Medtech application area “embraces all those technical textiles used in health and hygiene applications”

The medical application of textile fibres can be categorized into:– Extracorporeal devices

• Artificial kidney, liver, lung, heart pacer – Non-implantable textile materials

• Absorbent pad, bandages, compression bandages, plasters, absorbent gauges, lint and wadding

– Implantable textile materials• Tendons, ligaments, cartilage, skin, contact lenses, cornea,

joints, vascular grafts, heart valves– Healthcare and hygiene products

• Surgical gowns, caps, gloves , masks; surgical covers drapes, aprons; beddings (blankets, sheets, pillow covers); clothing (uniform); incontinence/baby/adult diapers; cloth wiper, surgical hosiery, sanitary napkins, medical mattress, sterilization wraps, head and shoe covers, panty shield, wadding; wipes

1. Non-implantable materials-

These materials used for external applications on the

body and may or may not make contact with skin.

Examples are: wound dressings, bandages, plasters,

Absorbent pad, compression bandages etc

SURGICAL DRESSING

These are employed as coverings, adsorbent, protective and supports for injured or diseased part. They are different types•Primary wound dressing•Absorbent•Bandages•Protective•Adhesive tapes

(i) PRIMARY WOUND DRESSING•Placed next to the wound surface•Nonwovens with a binder content of 60% are made of cellulose fabrics are being used.

A DRESSING SHOULD POSSESS THE FOLLOWING PROPERTIES:-•Healing properties, regulated mainly with the substances which are applied to or added to the dressing.•Decreased adherence surface.•Eliminating a possibility of loose fibers getting caught in the wound.•Easy penetration of wound secretion to the absorbing dressing.•Not- interrupted process of wound healing - as only the outer gauze compress is changed.•Painless changing of the dressing.

(ii) ABSORBENT •Similar to wound pads used in surgery. •Manufactured from well bleached, carded and cleaned cotton fabrics. •Absorbent lint is cotton of plain weave, warp nap raised on one side, used as an external absorbent and protective dressing and for the applications of ointments and lotions, as antiseptic adsorbent and protective dressing in first aid treatment.

BANDAGES 

These are narrow cotton or linen, plain weave cloth of low texture, either woven or knitted. There are different types:-• Cotton and rubber elastic net bandages- for sprains and strains.• Cotton rubber elastic net bandages- net fabric of lace construction.• Plaster of Paris bandages- cotton cloth is impregnated with a mixture of calcium sulphate.• Orthopedic cushion bandages.• Crepe bandage- elastic in nature due to special weave allows it to stretch twice its Length.

PROTECTIVE EYE PAD:-•Scientifically shaped to lit over the eye used in outpatient clinic and industrial department. ADHESIVE TAPES:-•It is narrow, plain weave fabric having a coating of adhesive paste. It is used with other pads to conform them on the injury.

TYPES AND USES OF SURGICAL DRESSING

STRIP BANDAGE IS THE MOST COMMON

FINGER TIP BANDAGE

KNUCKLE BANDAGE BUTTERFLY CLOSURE

DONUT BANDAGE PRESSURE BANDAGES

GAUZE ROLLS

TRIANGULAR BANDAGE

TENSOR BANDAGES

EYE PATCH ADHESIVE COTTON TAPE

Orthopaedic supports and medical compression stockings Here, special accessories developed by Stoll guarantee tension-controlled yarn feed and reliable weft thread insertion.

Wound dressingChronic wounds: 6.5 million

people - $25 billionImpaired healing – Inflammation

stage is prolongedResistance to

antibiotics

Silver impregnated dressings

Alternative metals, e.g. zinc as well as non-metal bactericides

Naturally derived compounds?

2. Extracorporeal devices- artificial kidney, liver, heart pacer and lung

3.Implantable materials- sutures, vascular grafts, artificial ligaments, cartilages, artificial joints, heart valves etc

4. Healthcare/hygiene products- bedding, clothing, surgical

gowns, cloths, wipes, Surgical gowns, caps, gloves , masks; surgical

covers drapes, aprons; beddings (blankets, sheets, pillow covers);

clothing (uniform); incontinence/baby/adult diapers; cloth wiper,

surgical hosiery, sanitary napkins, medical mattress, sterilization

wraps, head and shoe covers, panty shield, wadding; wipes

Requirements of textile material for medical applications

•Biocompatible and sterile•Anti Allergenic and anti Bacterial•Good resistance to alkalis, acids and micro-organisms•Good dimensional stability and elasticity •Free from contamination or impurities•Absorption / Repellency and air permeability•White staple fiber (no bleaching necessary).• Pure (without any dyes or other additives) •Manufactured under strict procedures and clean environment•Biodegradable and Environment friendly

• Polymer Processing– Drug-incorporated matrices can be formulated

either compression or injection molding– Polymer & drug can be ground in a Micro Mill,

sieve into particle size of 90-120 µm, then press into circular disc

– Alternatively drug can be mixed into molten polymer to form small chips, then it is fed into injection molder to mold into desired shape

Biodegradable Polymers as Drug Carrier Systems

• Polyesters– Lactide/Glycolide Copolymers

• Have been used for the delivery of steriods, anticancer agent, antibiotics, etc.

• PLGA is most widely investigated biodegradable polymers for drug delivery.

• Lactide/glycolide copolymers have been subjected to extensive animal and human trials without any significant harmful side effects

• Poly(amides)– Natural Polymers

• Remain attractive because they are natural products of living organism, readily available, relatively inexpensive, etc.

• Mostly focused on the use of proteins such as gelatin, collagen, and albumin

• Nanoparticles can be used to increase drug solubility, have lower toxicity & target drug delivery

• In order to use nanoparticle as drug delivery, they must satisfy number of criteria;– Biocompatible– Good drug payload– Manufacturing cost must be reasonable

Why nanoparticles are desired for drug delivery system?

Polymer for Dental Application

• Four main groups of materials used in dentistry;– Metal and alloys– Ceramics– Synthetic organic polymers & biopolymers

(derived from natural tissues)– Composites (an organic matrix polymers filled with

inorganic fine particles)

• Bases, liners and varnishes for cavities– There is a large diversity or organic and inorganic

materials for this purposes

– Zinc polycarboxylate (or polyacrylate) cement is prepared by mixing zinc oxide and the polymer solution, and water solution of polyacrylic acid

Polymer for Dental Application

• Filling & Restorative Materials– Made up of organic matrix and inorganic

particulate or fibrous filling. Held together by coupling agent

– PMMA resins have been used as filling materials, but they have several disadvantages

• Nonadhesion to dental structures• Low colour stability• Low molecular weight of monomer• High polymerization shrinkage

Polymer for Dental Application

• Suture- is a strand of textile materials (natural or synthetic), used to ligate blood vessel and draw tissue together

• Ideal suture should– Physical and mechanical properties (adequate tensile

strength, etc)– Handling properties (easy to handle)– Biological properties (unfavourable for bacterial growth)– Biodegradation properties (absorbable; its tensile strength

loss must match the healing rate of the tissue to be closed)

Textile based Biomaterials for Surgical Application

Resorb

Detail classifications of Medtex based on its scope

Recent Advances* Development of Polylactic acid polyglycolic

acid fibers as structures for cell growth.

* Development of smart fibers (Polymers/ Proteins) – for treatment of wounds & Ulcers

* Temporary bio-resource-able textile supports for growing human organic tissue