Oral and maxillofacial injuries
This chapter concentrates on injuries to the face. It covers the primary survey procedure to identify and manage life-threatening injuries and the subsequent assessment and care of injuries that occur to teeth, soft tissues and bones of the face. The techniques available for fixing facial fractures are described.
Guidelines for the management of the injury trauma patient initially developed by the American College of Surgeons have been widely adopted and disseminated through Advanced Trauma Life Support (ATLS) courses. These describe treatment priorities to achieve two aims: to save life and to restore function. A ‘primary survey’ is carried out simultaneously to identify and to manage life-threatening conditions and consists of the following:
Fig. 8.1 Trauma management primary survey.
Airway management skills are necessary because the trauma patient will not be able to maintain his or her own airway if unconscious or if the airway is compromised by serious facial soft tissue injury or facial fractures. However, airway skills are also important in other situations, such as when consciousness is altered by alcohol or other drugs, or when patients are treated with sedation and general anaesthesia. It is important to understand:
Airway obstruction may be recognised by the ‘look, listen and feel’ observations for breathing. Common causes of upper airway obstruction are the tongue and other soft tissues, blood, vomit, foreign body or oedema. Obstruction may be partial or complete:
Correction of airway obstruction is as described in Chapter 3 with the basic manoeuvre of chin lift or jaw thrust, use of oropharyngeal or nasopharyngeal airways and suction. The jaw thrust is the method of choice for the trauma victim as this avoids extension of a potentially injured neck, and the nasopharyngeal airway should be avoided if a fracture of the maxilla is suspected as it may pass into the cranial fossa. Airway compromise resulting from facial injury will require the early involvement of the oral and maxillofacial surgeon. Advanced airway management by way of endotracheal intubation is the ‘gold standard’ of airway maintenance and protection but is only carried out in the trauma situation after cervical spine radiograph has excluded bony injury.
Surgical airway intervention may be indicated, as a life-saving procedure, if it is not possible to intubate the trachea. This may consist of a needle cricothyroidotomy, in which a large-calibre plastic cannula is inserted into the trachea through the cricothyroid membrane (Fig. 8.2). Alternatively, a surgical cricothyroidotomy may be undertaken with a transverse incision through the membrane to permit placement of a small endotracheal tube. These measures can provide up to 45 minutes of extra time in which to arrange undertaking an emergency tracheostomy in a theatre environment. A transverse skin incision is made midway between the cricoid cartilage and the suprasternal notch followed by midline dissection of the infrahyoid muscles and division of the thyroid isthmus. Haemostasis is achieved and then the trachea is opened by cutting away part of the second and third rings to create a circular opening so that a tracheostomy tube may be placed and secured (Fig. 8.3).
Fig. 8.2 Needle cricothyroidotomy.
Fig. 8.3 Insertion of tracheostomy tube.
Once an airway has been established, then the adequacy of ventilation must be assessed. Artificial ventilation must be commenced immediately when spontaneous ventilation is inadequate or absent using a self-inflating bag and mask with attached oxygen (see Chapter 3). Serious chest injuries such as tension pneumothorax and cardiac tamponade will compromise spontaneous ventilation. Early diagnosis of these potentially life-threatening conditions is essential so that they can be managed and permit adequate ventilation of the patient. An orogastric rather than nasogastric tube is placed when there is suspicion of base of skull fracture to decompress the stomach. A pulse oximeter monitors atrial oxygen saturation.
Haemorrhage should be controlled by pressure to bleeding wounds or by applying an artery forcep or ligature to a severed artery as appropriate. Bleeding from a fractured maxilla will not be controlled unless it is manually repositioned, although this emergency is rare. If all local measures fail to control haemorrhage from the maxillofacial region then it may be necessary to consider ligation of the external carotid artery.
Intravenous fluids should be infused via a large peripheral vein such as in the antecubital fossa. When there is a need to maintain blood pressure, plasma expanders such as Gelofusine or Haemaccel are better than crystalloids, such as sodium chloride, as they remain in the vascular compartment for longer. Urinary catheterisation is required and adequate fluid replacement is monitored by documenting urine output, peripheral perfusion and temperature. The prognosis is better when the patient is warm with full veins and a good urine output. Electorcardiographic (ECG) monitoring is undertaken.
A rapid initial assessment of conscious state can be made using the AVPU method: Alert, responds to Vocal stimuli, responds to Painful stimuli or Unresponsive to all stimuli. Alternatively the Glasgow Coma Scale, which records the patient’s motor, verbal and eye movements in response to stimulation, may be used.
All of the victim’s clothing is removed to permit full assessment and exclude other injuries, taking into account the environmental conditions and respecting the patient’s dignity. A warming blanket is placed and i.v. fluids are warm.
A secondary survey is carried out once the patient’s general condition has been stabilised. This consists of a top-to-toe detailed patient examination of all body systems and a more thorough neurological examination, including testing of the cranial nerves. The particular role of the oral and maxillofacial surgeon in the secondary survey is to carry out a detailed examination of the head, neck and orofacial region. Appropriate radiographs or other investigations such as computed tomography (CT) can then be arranged and definitive care planned.
The situation must be dealt with very delicately if there is the suspicion of NAI and it is better not to involve the parents in any discussion at this early stage. It may be useful to arrange admission of the child to hospital and discuss suspicions with a paediatrician. When presentation and management take place in an accident and emergency (A&E) department, the dentist may request a check of the local child protection register, best done via the nominated lead nurse or clinician for child protection procedures.
The face is a common target in assault and consequently the dentist and dental care professional have a part to play in identifying domestic violence. Domestic violence is a term which refers to a wide range of physical, sexual, emotional and financial abuse of people who are, or have been, intimate partners – whether or not they are married or cohabiting. Although domestic violence can take place in any intimate relationship, including gay and lesbian partnerships, and while abuse of men by female partners does occur, the great majority and the most severe incidents of domestic violence are perpetrated by men against women.
It is not the job of the dentist or dental care professional to give advice to someone experiencing domestic violence on what direct action they should take but rather to identify violence and provide information about where the individual can go for help.
Dental injures are more common in children than adults. In children, they are frequently the result of falls, and in adults, they are commonly the consequence of sport without mouthguard protection. Increased overjet and incompetent lips are predisposing factors.
Fig. 8.4 Examples of some dental injuries.
Table 8.1 gives the management for injuries to primary and permanent teeth. Reassurance and analgesia are especially important for children. Patients will require regular review to assess development of late sequelae.
Splints can be directly constructed in the mouth of the patient or indirectly constructed on a model in a laboratory. Direct splints may be made from foil adapted over the teeth and cemented with zinc oxide eugenol or better with composite that is attached to the teeth over a wire using an acid-etch technique.
Soft tissue injury may result from interpersonal violence, road traffic accidents, falls, sport and industrial accident. Weapons may or may not be involved. Facial injury may also result from burns either as an isolated injury or in association with burns of the trunk or other part of the body.
Lacerations and wounds may involve anatomical structures such as the facial nerve, resulting in facial paralysis, the parotid salivary gland duct, resulting in a salivary fistula, or arteries, resulting in significant blood loss. They may be ‘clean’ or obviously contaminated. Burns are described according to their depth and extent. They may be superficial (first-degree burn), partial thickness (second-degree burn) or full thickness (third-degree burn). The ‘rule of nines’ may be used to describe the total body surface area affected by burn: 9% for each arm and the head, 18% for each leg, front and back of trunk and 1% for the external genitalia. The rule is modified for children who have a relatively larger head and face. The estimation is important for calculating fluid replacement.
Radiographs of the soft tissues may be necessary to locate glass or other foreign body in a wound or to exclude an underlying bony injury. Soft tissue radiographs are taken with reduced exposure to avoid ‘burn-out’ of low-density debris, and using intraoral films wherever possible for greatest detail.
Small, straightforward lacerations may be managed by A&E physicians or senior nurses. Lacerations involving the vermilion border of the lip, intraoral lacerations, other more serious lacerations and gunshot wounds will be referred on to an oral and maxillofacial surgeon. General dentists may undertake management of intraoral lacerations in a primary care setting.
Small lacerations can usually be sutured under local anaesthesia unless the patient is a young child, in which case general anaesthesia is indicated. Thorough cleaning is necessary before wound closure. Skin lacerations are closed with absorbable material such as polyglactin (Vicryl) placed deep if necessary and then the overlying skin closed with fine non-absorbable material such as 6/0 Prolene or Ethilon. Intraoral wounds may be closed with Vicryl or silk. It is important when repairing a lip laceration which involves the vermilion border that it is accurately lined up to avoid an ugly step on healing.
Antibiotics are prescribed to reduce the risk of wound infection: flucloxacillin for skin lacerations and amoxicillin for intraoral wounds, unless contraindicated. Tetanus prophylaxis should be recommended if immunisation is not up to date.
Initial management according to ATLS. There could be late threat to airway due to scar contracture. During the initial 48 hours, the patient is hypovolaemic due to pericapillary tissue exhudation and tissue oedema. After 48 hours, the patient becomes diuretic and fluid replacement demands reduce.
Analgesia is required and prevention of wound infection with antibiotics and dressings. The area of burn may require excision. Partial-thickness burns may be best left exposed to the air when epithelialisation may start at 12 days. Reconstruction may be with skin grafts or microvascular free tissue transfer.
Facial fractures may result from interpersonal violence, road traffic accidents, falls, sport and industrial accident or from pathology resulting in weakness of a bony region. There is a decline in the number of injuries following road traffic accidents, mainly because of the wearing of seat belts, although this has not been as great as hoped because drivers choose to drive at greater speeds because they feel safer. There is a rise in the number of facial fractures following assault. Facial injuries incurred through domestic violence are being increasingly recognised. The commonest fracture is that of the mandible.
Examination consists of the palpation of bony margins of the facial skeleton starting with the supraorbital rims and progressing down to the lower border of the mandible, comparing right and left sides. The eyes are examined for double vision (diplopia), any restriction of movement and subconjunctival haemorrhage. The condyles of the mandible are palpated and movements of the mandible checked. Swelling, bruising and lacerations are noted together with any areas of altered sensation that may have resulted because of damage to branches of the trigeminal nerve. Any evidence of cerebrospinal fluid leaking from the nose or ears is noted, as this is an important feature of a fracture of the base of the skull. An intraoral examination is then carried out, looking particularly for alterations to the occlusion (Fig. 8.5), a step in the occlusion (Fig. 8.6), fractured or displaced teeth, lacerations and bruises. The stability of the maxilla is checked by bimanual palpation, one hand attempting to mobilise the maxilla by grasping it from an intraoral approach, and the other noting any movement at extraoral sites such as nasal, zygomatic-frontal and infraorbital. Features that suggest the fracture of a particular part of the facial skeleton are: