Serge Mordon
INSERM & Lille University Hospital, Lille, France
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19.1 |
Introduction |
369 |
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19.2 |
Low-Level Laser Therapy (LLLT) |
370 |
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19.2.1 Photomodulation |
371 |
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19.2.2 Experimental Studies |
373 |
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19.2.3 Clinical Studies |
374 |
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19.3 |
Light Emitting Diodes |
374 |
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19.3.1 Experimental Studies |
375 |
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19.3.2 Clinical Studies |
375 |
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19.4 |
Lasers |
375 |
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19.5 |
Conclusions |
378 |
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References |
379 |
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19.1 |
1 ntroduction |
Wound healing is a complex and dynamic process of restoring cellular structures and tissue layers. The human adult wound-healing process can be divided into 3 distinct phases: the inflammatory phase, the proliferative phase, and the remodeling phase. Within these three broad phases is a complex and coordinated series of events that includes chemotaxis, phagocytosis, neocollagenesis, collagen degradation, and collagen remodeling. In addition, angiogenesis, epithelization, and the production of new glycosaminoglycans (GAGs) and proteoglycans are vital to the wound-healing milieu (Fig. 19.1). The culmination of these
Gurpreet S. Ahluwalia (ed.), Cosmetic Applications of Laser and Light-Based Systems, 369-380,
© 2009 William Andrew Inc.
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Figure 19.1 The three phases of wound healing from [36]. |
biological processes results in the replacement of normal skin structures with fibroblastic mediated scar tissue [1].
This process can go awry: (i) it can produce an exuberance of fibroblastic proliferation with a resultant hypertrophic scar, which by definition is confined to the wound site; (ii) further exuberance can result in keloid formation where scar production extends beyond the area of the original insult; (iii) conversely, insufficient healing can result in atrophic scar formation; and (iv) the normal reparative process can be interrupted, leading to a nonhealing chronic wound.
If the treatment of acute wounds is well-defined (but it could be still improved), there is still much debate over which treatment modality to use for the treatment of nonhealing chronic wounds. Finally, the wound-healing process has been used for skin rejuvenation. However, this specific application will not be covered in this chapter.
Since the complex wound-healing process is influenced by so many factors, we always must recall the words of Ambroise Pare (1510-1590): “I dressed the wound; GOD healed it.”
As we enter the twentieth century, light systems are now proposed to promote wound healing. This chapter summarizes several studies performed to date with different light systems in order to demonstrate if light-based systems could (or could not) play a role to promote wound healing.