Alloplastic or Homograft Implantation for Nasal Reconstruction

Matthew D. Mingrone, David B. Lovice, and Dean M. Toriumi

CHAPTER 31

Functional and cosmetic rhinoplasty often mandates the need for implantable materials to change nasal contour or provide improved support for the nasal framework and overlying soft tissues. There are many implant materials, which can be divided into three main categories: autografts, homografts, and allo-plasts. Autografts are those harvested from the patient and include, among others, cartilage, bone, dermis, fat, and fascia. Homografts, such as cartilage, bone, and dermis, are materials procured from donors of the same species. Alloplasts encompass a large group of synthetic and semisynthetic materials used as implants. A fourth group of materials, xenografts, are those implant materials harvested from other species, such as bovine collagen. The latter group is relatively small and therefore is not discussed further. Each category of graft maintains notable advantages and disadvantages, as outlined in Table 31-1. The controversy as to which material is superior is not a new one, and will continue to be debated until a group of alloplastic materials are developed that satisfy the basic needs of the ideal implant. A suitable implant must be biocompatible, strong, and elastic. The material should be completely inert, incapable of inducing inflammation or allergy, noncarcinogenic, resistant to mechanical strain, easily modified for shaping, and sterilizable.

Surgical needs, patient selection, and the surgeon's preference and experience are all factors that influence the choice of material for a given circumstance. Most would agree that auto-grafts should remain the primary choice for nasal reconstruction and rejuvenation. Situations do arise, however, in which harvesting a graft is impractical or increases the morbidity of a procedure in a patient with borderline medical status. Additionally, sufficient autogenous material may not exist to satisfy the surgical needs of the patient. For these situations, homo-graft materials are an adequate substitute to autografts. Graft

TABLE 31-1

Implants in Rhinoplasty: Advantages and Disadvantages

TABLE 31-1

Implants in Rhinoplasty: Advantages and Disadvantages

Autografts

Alloplasts

Homografts

Advantages

1.

Biocompatibility

1.

Strength

1.

Biocompatibility

2.

Strength (bone)

2.

Elasticity

2.

Strength (bone)

3.

Ability to contour (cartilage)

3.

Durability

3.

Ability to contour (cartilage)

4.

Ability to camouflage (fascia)

4.

No donor site morbidity

4.

Ability to camouflage (fascia,

5.

Unlimited supply

AlloDerm)

6.

Decreased surgical time

5.

No donor site morbidity

6.

Unlimited supply

7.

Decreased surgical time

Disadvantages

1.

Donor site morbidity

1.

Higher extrusion rate than

1.

Resorption

2.

Memory (cartilage)

autografts

2.

Warping (cartilage)

Rare resorption

2.

Higher infection rate

Extrusion

3.

3.

4.

Limited material

3.

Higher cost

4.

Higher infection rate

5.

Increased surgical time

5.

Higher cost

6.

Patient confidence with

implant safety

SOURCE: Lovice DB, Mingrone MD, Toriumi DM. Grafts and implants in rhinoplasty and nasal reconstruction. Otolaryngol Clin North Am 1999; 32:113-41

SOURCE: Lovice DB, Mingrone MD, Toriumi DM. Grafts and implants in rhinoplasty and nasal reconstruction. Otolaryngol Clin North Am 1999; 32:113-41

TABLE 31-2 Implant Materials

Alloplastic Materials

Autologous Materials

Homologous Materials

Metals Titanium Vitalium Stainless steel

Ceramics

Polymers Silicone Polyethylene

Polytetrafluoroethylene (PTFE)

Polyesters

Polyamides

Resorbable materials Suture

Septal cartilage grafts Rib grafts

Auricular cartilage grafts

Calvarial bone grafts

Other bone grafts

Tissue flaps

Cutaneous flaps Mucosal flaps

Irradiated and nonirradiated costal cartilage Acellular dermis (AlloDerm)

location must also be considered when choosing an implant. Grafts for the relatively immobile dorsum may undergo less resorption than those placed in the nasal tip (Table 31-2).

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