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A modified arch bar for use in patients with anterior crowns or bridgework
TECHNICAL
NOTE
A modified arch bar for use in patients with anterior crowns or bridgework Ii.
1’. Kees, .I. E. Rowson
Department
oJ’ Oral and Maxillojhcial Surgery,
SUMMARY. bridgework.
A moditication
West Norwich Hospitd,
to the wrought arch har is described
INTRODUCTION Intermaxillary fixation still occupies a place in the management of fractures of the facial skeleton and in orthognathic surgery. A variety of methods have been evolved to achieve this and wrought arch bars provide a reliable and adaptable technique. An increasing number of patients have anterior porcelain crowns or bridgework and this poses certain problems. Placing wires around individual teeth to hold the bar in place may damage the porcelain or dislodge the crown or bridge. Other wiring tcchniqucs have the same disadvantages and cast cap splints also pose a risk. Extraoral pin fixation techniques overcome the problem of damage to crowns and bridges but arc conspicuous and very inconvenient to patients. Internal suspension tcchniques have been used successfully but it is more difficult to maintain a forward pull on the mandible and their placement is a more demanding technique. With thcsc disadvantages in mind a modification of the arch bar has been devised which does not require attachment directly to the anterior teeth. This method also allows the use of elastics for intermaxillary fixation.
TECHNIQUE Impressions of the teeth are taken and models made. Archbars with cleats arc constructed using oval German silver wire in the usual manner. For the upper arch. two vertical prongs. 4 cm long. are soldered to the bar approximately 7 mm on either side of the midline, projecting superiorly. The distance between them is estimated using the postcro-anterior ccphalogram (Fig. I ). The vertical prongs are bent in the sagittal plant to conform to the concave surface of the premaxilla (Fig. 2). At operation an incision is made high in the buccal sulcus anteriorly, approximately 2 cm long and the
Norwich
for use in patients with anterior crowns or
piriform fossae are exposed. ‘I’hc mucoperiostcum of the floor of the nose is elevated on cithcr side for approximately 2 cm. The archbar is now taken and the prongs are bent at right angles so that they lie along the floor of the nose. The point at which the bend is made may be determined directly at opcration, or pre-operatively by measurement of the lateral cephalogram. The archbar is next offered up to the teeth and the prongs inserted to lie along the floor of the nose subpcriostially (Figs 2 & 3). Finally the archbar is wired to one or mot-c posterior teeth on each side in the usual way and the mucosa sutured (Fig. 4). In the lower arch the vertical prongs arc soldered about 15 mm apart. They should be bent to conform
196
British
Journal
of Oral
and hlaxillofacial
Surgerv
to the contour of the anterior surface of the mandible. hooking around the lower border. Care should be taken not to place the prongs too far apart since this causes difficulty in placing them around the lower border. At operation a long incision is made in the buccal sulcus anteriorly avoiding the
Fig. 4-Intraoral
view of archbars in situ
mental nerves. The mucoperiosteum is elevated to the lingual aspect of the lower border. The archbar is offered up and the prongs placed around the lower border. The bar is then wired to the posterior teeth as usual and the mucosa sutured. Following healing, an upper bar may be easily removed using local anaesthcsia to the buccal sulcus and floor of nose. A lower bar is more difficult to remove and may require general anacsthesia. The original incision is opened and it may be necessary to cut the prongs off the bar to facilitate its removal. Although there is a potential route for infection vicethe mucosal entry site of the prongs. in practice this has not been a problem. However, antibiotic prophylaxis is recommended for the first few days.
I)ISCUSSION The method described provides a simple way of achieving jawimmobilisation in patients with anterior crowns or bridgework. Since the bar is not fixed to the teeth in any way it does not damage them. The placement of the upper bar is quick and simple as is its removal. The lower bar is less easy to USC but does provide excellent fixation.
Acknowledgements The
authors wish IO thank Mr K. Hewitt. ‘I echnician for constructing the archhars models and the Department of hGAical Norwich Hospitals for the photographs.
Chief
Maxillofacial
:md demonstration Illustration. llnited
The Authors R. T. Rees MB RS, FDSRCS Consultant J. E:. Ruwson BMcdSci, FDSRCS, FRCS Kcgistrar Dcpartmcnt of Oral and Maxillofaci:d Hoxpital. Norwich. NIV 3’IIl (‘orrcxpondcncc Fig.3-Modclshowin~archh;lrs;Id;lplcd jaws.
touppcrand
Iowcr
Surgery,
b’cxt
and rcqucsts for offprints to II. ‘I‘. Rccs
Paper rcccivcd 29 Scptcmhcr Acccptcd I I Novcmbcr I991
IWI
Norwich
NOTE
A modified arch bar for use in patients with anterior crowns or bridgework Ii.
1’. Kees, .I. E. Rowson
Department
oJ’ Oral and Maxillojhcial Surgery,
SUMMARY. bridgework.
A moditication
West Norwich Hospitd,
to the wrought arch har is described
INTRODUCTION Intermaxillary fixation still occupies a place in the management of fractures of the facial skeleton and in orthognathic surgery. A variety of methods have been evolved to achieve this and wrought arch bars provide a reliable and adaptable technique. An increasing number of patients have anterior porcelain crowns or bridgework and this poses certain problems. Placing wires around individual teeth to hold the bar in place may damage the porcelain or dislodge the crown or bridge. Other wiring tcchniqucs have the same disadvantages and cast cap splints also pose a risk. Extraoral pin fixation techniques overcome the problem of damage to crowns and bridges but arc conspicuous and very inconvenient to patients. Internal suspension tcchniques have been used successfully but it is more difficult to maintain a forward pull on the mandible and their placement is a more demanding technique. With thcsc disadvantages in mind a modification of the arch bar has been devised which does not require attachment directly to the anterior teeth. This method also allows the use of elastics for intermaxillary fixation.
TECHNIQUE Impressions of the teeth are taken and models made. Archbars with cleats arc constructed using oval German silver wire in the usual manner. For the upper arch. two vertical prongs. 4 cm long. are soldered to the bar approximately 7 mm on either side of the midline, projecting superiorly. The distance between them is estimated using the postcro-anterior ccphalogram (Fig. I ). The vertical prongs are bent in the sagittal plant to conform to the concave surface of the premaxilla (Fig. 2). At operation an incision is made high in the buccal sulcus anteriorly, approximately 2 cm long and the
Norwich
for use in patients with anterior crowns or
piriform fossae are exposed. ‘I’hc mucoperiostcum of the floor of the nose is elevated on cithcr side for approximately 2 cm. The archbar is now taken and the prongs are bent at right angles so that they lie along the floor of the nose. The point at which the bend is made may be determined directly at opcration, or pre-operatively by measurement of the lateral cephalogram. The archbar is next offered up to the teeth and the prongs inserted to lie along the floor of the nose subpcriostially (Figs 2 & 3). Finally the archbar is wired to one or mot-c posterior teeth on each side in the usual way and the mucosa sutured (Fig. 4). In the lower arch the vertical prongs arc soldered about 15 mm apart. They should be bent to conform
196
British
Journal
of Oral
and hlaxillofacial
Surgerv
to the contour of the anterior surface of the mandible. hooking around the lower border. Care should be taken not to place the prongs too far apart since this causes difficulty in placing them around the lower border. At operation a long incision is made in the buccal sulcus anteriorly avoiding the
Fig. 4-Intraoral
view of archbars in situ
mental nerves. The mucoperiosteum is elevated to the lingual aspect of the lower border. The archbar is offered up and the prongs placed around the lower border. The bar is then wired to the posterior teeth as usual and the mucosa sutured. Following healing, an upper bar may be easily removed using local anaesthcsia to the buccal sulcus and floor of nose. A lower bar is more difficult to remove and may require general anacsthesia. The original incision is opened and it may be necessary to cut the prongs off the bar to facilitate its removal. Although there is a potential route for infection vicethe mucosal entry site of the prongs. in practice this has not been a problem. However, antibiotic prophylaxis is recommended for the first few days.
I)ISCUSSION The method described provides a simple way of achieving jawimmobilisation in patients with anterior crowns or bridgework. Since the bar is not fixed to the teeth in any way it does not damage them. The placement of the upper bar is quick and simple as is its removal. The lower bar is less easy to USC but does provide excellent fixation.
Acknowledgements The
authors wish IO thank Mr K. Hewitt. ‘I echnician for constructing the archhars models and the Department of hGAical Norwich Hospitals for the photographs.
Chief
Maxillofacial
:md demonstration Illustration. llnited
The Authors R. T. Rees MB RS, FDSRCS Consultant J. E:. Ruwson BMcdSci, FDSRCS, FRCS Kcgistrar Dcpartmcnt of Oral and Maxillofaci:d Hoxpital. Norwich. NIV 3’IIl (‘orrcxpondcncc Fig.3-Modclshowin~archh;lrs;Id;lplcd jaws.
touppcrand
Iowcr
Surgery,
b’cxt
and rcqucsts for offprints to II. ‘I‘. Rccs
Paper rcccivcd 29 Scptcmhcr Acccptcd I I Novcmbcr I991
IWI
Norwich