The chance comes only once, and if it is missed the results can be difficult to cor-rect. As already stressed, it may be apparent that Z-plasties will be required later, but these should not be used at the primary operation. When tissue has been lost the governing prin-ciple is that surviving tissues should be replaced in their correct position so that the defect can be properly displayed and assessed in terms of the tissues lost.
The experienced plastic surgeon might then consider the possibility of a definitive primary reconstruction, though probably only to discard the thought. The less experienced sur-geon should certainly have a more modest target and, if the defect cannot be closed directly with-out creating distortion, he should apply a split skin graft in most instances.
Such an approach has the merit of allowing healing to occur quick-ly with minimal scarring and leaves conditions suitable for a definitive repair or reconstruction subsequently. Ideally, wound edges being sutured together should be vertical if the best scar result is to be achieved, and accurate suturing is also very much easier when the faces of tissue brought together are of the same thickness.
In the case of facial injuries, particularly those resulting from windscreen trauma, neither may be present, shelv-ing lacerations being the norm. A compromise from the ideal situation is then unavoidable. Excision to create vertical wound margins would involve unacceptable sacrifice of viable tissue in many instances, and then only sufficient of the wound edges is excised to remove clearly devi-talised tissue.
The residual shelving makes suturing more difficult, but it has to be accepted as the lesser of two evils. In practice the best result is achieved by using a large number of very fine sutures, and even then the need for possible revision or dermabrasion of the result-ing scar subsequently has to be accepted.