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[1]
In the International Classification of Diseases [9th revision- aspiration. Pindborg et al. found an incidence of 38% tongue
World Health Organization (WHO)], oral cancer is classified involvement in OSMF, which precludes its use. Bilateral free
under the rubrics 140 (lip), 141 (tongue), 143 (gingiva), 144 radial artery forearm free flaps require micro vascular expertise,
(floor of the mouth), and 145 (other parts of the mouth). Oral the flaps are hairy and 40% of patients require secondary de-
precancer is distinguished by WHO into “precancerous lesions” bulking procedures. Extraction of third molar tooth is required
(e.g. leukoplakia, erythroplakia) and “precancerous conditions” to avoid flap inclination between teeth.
[31]
(e.g. oral sub mucous fibrosis, lichen planus). The treatment
of these suspicious precancerous lesions involve wide excision Chemically, bovine collagen is very similar to the human form.
followed by grafting of the surgical sites. Depending on the This is crucial, as the human immune system will reject everything
status of metastasis of established malignancies, resection of that deviates too much from its own proteins. For these reasons,
affected area and radical neck dissection followed by adjuvant collagen sheets are well qualified for use as an effective wound
[7]
radiotherapy with or without chemotherapy may be required. In cover. Bovine collagen contain mostly type I and III collagen,
the surgery of oral submucous fibrosis (OSMF), bilateral fibrotic packed in a neutral glass vial of sterile preservative mixture of
bands are excised with or without bilateral coronoidectomy or isopropyl alcohol and water sterilized with ethylene oxide and
temporalis myotomy. are available in different sizes for clinical application. The freeze-
dried form of collagen is also available so that there is no need to
In all such cases, wounds left uncovered are prone to infection, treat the membrane in normal saline before application. Meshed
contraction, and scarring with other clinical complications. collagen membrane in wet form, porous collagen dressing
Raw wounds of the oral cavity, like any other wounds, heal by and collagen film dressings are also available. Wet collagen
[6]
epithelialization and granulation. However, in the oral cavity the membrane comes in varying in dimensions of 10 cm × 10 cm,
healing of raw wounds presents some special problems. The 10 cm × 25 cm and 25 cm × 25 cm with thickness of 0.6 mm. [35]
environment is always moist with contamination from salivary
secretion and food ingestion. This, compounded by poor oral Collagen covers sensitive nerve endings, thereby diminishing
hygiene and constant movements of the cheek and tongue degree of pain in raw wounds. Initially collagen adheres due to
and masticatory forces, may interfere with graft adherence and fibrin collagen interaction and later by fibrovascular ingrowth
acceptance. The risk of infection in the oral cavity is also quite into the collagen. All collagen membranes, with time, slowly
high, which may result in scarring and contraction. The oral cavity undergo collagenolysis and get eventually sloughed off. [1]
is highly sensitive to any residual scarring, which may undergo
ulceration and could be a constant source of irritation to patients The advantages of collagen sheet as a wound dressing material
wearing dentures. Hence, a need arises to use a biologic cover to in surgery precancerous and cancerous lesions of oral soft tissues
prevent these complications. [32] include the easy availability of collagen sheet, convenience of
application, good tolerance of oral tissue, no adverse effects
Free split-skin graft and free mucosal graft have been used to of the use of this membrane, obviation of second surgery to
cover raw wounds in the oral cavity. The use of these grafts obtain graft or detachment of the pedicle, there is no morbidity
required a separate surgical procedure with associated technical associated with the use of grafts, and there are no problems
difficulties. The color and texture of skin do not conform totally associated with donor site healing. [34,36] No threat of human
to the oral cavity. Also seen is the growth of adnexal structures immunodeficiency virus or hepatitis infections is associated with
such as hair and sweat glands. In elderly persons the skin is collagen, as the bovine material is obtained from countries free
atrophic and inelastic, making it unsuitable. Mucosal grafts offer of bovine spongiform encephalopathy and has a long shelf-life
the best solution because they come nearest to fulfilling the under normal storage conditions. [7]
requirements of an ideal graft material, which include the ability
to replace lost structures and the ability to induce the formation OSMF is an insidious chronic disabling disease involving
of such tissues. Donor sites for mucous graft are limited, and oral mucosa, oropharynx and rarely larynx characterized by
there is always morbidity associated with donor-site healing. The juxtaepithelial inflammatory reaction followed by progressive
oral environment and its constant movements are impediments fibrosis of the lamina propria and deeper connective tissues
to graft acceptance. Other reconstructive options which have with concomitant muscle degeneration. Although vesicle
[32]
been used in the past include nasolabial flaps, transposition of formation is an early sign, patient’s usual complaint will
the buccal pad of fat, dorsal tongue flap, radial forearm flaps, barely be burning sensation and inability to have hot and spicy
flaps of the temporalis fascia/muscle or both, palatal island flaps food. In the later stages, it shows a tendency for progressive
to cover surgical defects, each having their own advantages and fibrosis, leading to gradual reduction in mouth opening which
shortcomings. [33,34] Use of island palatal flap has limitation such as hinders the function. [37,38] Management of trismus in OSMF is
its involvement with fibrosis and second molar tooth extraction extremely challenging because of the nature of the disease,
is required for flap cover without tension. Bilateral palatal flaps making the oral mucosa prone to contraction causing a
leave a large raw area on palatal bones. Sometimes the defect significant reduction in the interincisal opening that was
[1]
created may be large and local flaps may not be able to cover the achieved with surgery. Nataraj et al. performed a study in
entire defect. A nasolabial flap is too short to cover the defect which collagen was used to cover surgical defects of OSMF
and causes visible scaring on the face and requires division at in 15 cases and in other 15 cases, buccal pad of fat was used
second stage. Tongue flaps have been used to cover the buccal for the same. They found that the use of collagen membrane
defects but were found to be bulky and needed additional following excision of fibrotic bands in the management of oral
surgery for detachment. Bilateral tongue flaps can cause severe submucous fibrosis, though statistically not significant gave
dysphagia and disarticulation and carry the risk of postoperative better results with respect to post operative mouth opening
102 Plast Aesthet Res || Vol 3 || Mar 23, 2016