fractures it is important to prevent posterior collapse of the symphysis, and more than two pairs of pins may be required. Great care must be taken to avoid the inferior dental bundle, especially in the atrophic edentulous case, and to prevent the drill from slipping under the lower border of the mandible. Very occasionally, screwing pins too tightly into an atrophic mandible will result in a split in the bone which joins the two holes. It is easy to displace or traumatize the skin when inserting pins. This will result in skin necrosis, which continues if pressure of the skin against the pin is allowed to persist and results in unsightly scarring,. Care is, therefore, required to prevent skin distortion by inserting the pin to compensate for the final position of the underlying bony fragments after reduction of the fractures. Should some slight heaping up of the skin against the shaft persist after insertion, a minimal stab incision should be made to relieve the tension and allow the skin to adapt itself around the pin. THE PIN SITES : The entry sites may be covered by a dressing such as tulle
or,
preferably, by 1.25 cm wide ribbon gauze soaked in Whitehead’s varnish (Pigmentum Iodoform Compound) and then squeeze-dried and wrapped in a figure-of-eight pattern around the base of the shaft. These dressings require renewal or repositioning when the entry wound becomes exposed as the o edema subsides. Although hey may be disturbed by the patient, the enry