ARTÍCULO CLÍNICO

 

Complications of self-tapping bone screws for maxillomandibular fixation in the treatment of jaw fracture

Complicaciones de los tornillos de bloqueo intermaxilar en el tratamiento de las fracturas mandibulares

 

 

J. Molina Montes¹, J. González-Lagunas², J. Mareque Bueno¹, J.A. Hueto Madrid², G. Raspall Martí³

¹ Médico Residente
² Médico Especialista
³ Jefe de Servicio
Servicio Cirugía Oral y Maxilofacial. Hospital Universitario Vall d’Hebrón, Barcelona. España

Correspondence

 

 

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ABSTRACT

In the last decade, self-tapping bone screws have been used widely as a temporary maxillomandibular fixation method in the treatment of jaw fractures. The purpose of the present study was to evaluate the complications of the technique and potential dental iatrogenesis over a period of 4 years. We reviewed a total of 62 patients and 272 screws. Although complications appeared, the complication rate was low.

Key words: Maxillomandibular fixation; Jaw fracture; Complications; surgery.

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RESUMEN

Durante la última década se ha introducido el tornillo de bloqueo intermaxilar como método de fijación maxilomandibular en el tratamiento de las fracturas de mandíbula. El propósito del estudio es evaluar las complicaciones de la técnica y la yatrogenia dental que derivan de su aplicación durante un periodo de 4 años. Se han revisado un total de 62 pacientes y 272 tornillos y, aunque han aparecido complicaciones, su incidencia es baja.

Palabras clave: Fijación intermaxilar; Fractura mandibular; Complicaciones; Fractura mandibular; Cirugía.

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Introduction

Jaw fractures usually require temporary maxillomandibular fixation in correctly aligned occlusion for fracture reduction before fixation. The standard method for many years has been maxillomandibular fixation with arches and wires, which is uncomfortable and poorly tolerated by the patient. It also causes periodontal damage and makes oral hygiene difficult. The insertion of self-tapping bone screws for maxillomandibular fixation have replaced wiring the mouth shut as a quicker and easier method that is better tolerated by patients and is less likely to produce prick wounds in the surgeon than wires.

The aim of this study was to review the incidence of dental iatrogenesis produced by bone screws for maxillomandibular fixation.

 

Material and method

We reviewed the patients treated for jaw fracture in our maxillofacial surgery department between January 2002 and June 2006. In 62 patients, bone screws for maxillomandibular fixation were used to provide stable jaw fixation with the aid of wires or elastic bands.

Of the 62 patients enrolled in the study, 52 were men (62%) and 10 women (16%). Patient age range was 17 to 57 years.

The bone screws were of 316L steel, 8 to 12 mm long, with a diameter of 2.0 mm. The most important feature was that the bone screws were self-tapping did not require drilling before inserting them transmucosally.

The most frequent type of jaw fracture was condylar/subcondylar (30.6%) (Table 1).

 

A total of 272 bone screws were placed and remained positioned for a mean of 6 weeks. At least one screw was positioned in each quadrant (Fig.1). Three screws were placed in one patient due to technical complications during the surgical procedure.

Bone screws were placed by different staff members and medical residents who used preoperative panoramic radiography as a guide for locating dental roots.

All patients were given postoperative antibiotic therapy for 7 days. Patients were followed up clinically for a mean of 6 months with postoperative panoramic radiography and once more after screws were removed. Tooth viability was tested in two situations: (a) in teeth in which the screws appeared to have damaged the root on radiography and (b) when neighboring teeth presented clinical sensitivity to cold/heat.

 

Results

The most frequent complication observed was mucosal overgrowth of the screw, which occurred in 13 of the 272 screws inserted (4.7%). Screws were removed without anesthesia except for these 13 patients, who required infiltration of local anesthesia. None of the screws was lost but 5 screws were loose when removed (1.8%).

When the self-tapping bone screws were inserted, 5 (1.8%) screws fractured at the point of union between the head and shaft (Figs. 1 and 2). The screws were inserted by different members of the department, had different lengths, and were placed in both the mandible and maxilla.

Root injury (defined as radiographic evidence of contact between a screw and a dental root) occurred in 4.4% of cases (Figs. 3 and 4). In 10 patients, the screw scratched the root but did not originate clinical symptoms. Vitality tests yielded normal results and the affected tooth showed no loosening.

In 2 patients (0.8%), pulp vitality tests were positive and dental sensitivity was affected. Only one of these teeth required root canal during the postoperative follow-up, which was the most important complication of the study (Figs. 5-6-7/9).

The discomfort that occurred in 4.4% of patients was related to the dwell time of the screw in the mouth. The most frequent complication was ulceration of the labial mucosa and residual pain after the screw was removed.

 

Discussion

Different methods of external stabilization have been used to produce maxillomandibular fixation in the treatment of jaw fractures. Up until a few years ago, the most common method of immobilization was using splints and wire ties around the teeth. However, bone screws for maxillomandibular fixation have displaced splints described since Arthur and Berardo described the technique in 1989. Many advantages over the classic method have been described, including easy placement, shortened surgical time, better oral hygiene, ease of removal without anesthesia, and reduction of the risk of prick wounds and the attendant transmission of contagious disease to surgeons.^1-5 Another important advantage is that screws make smaller wounds in the dental papilla and oral mucosa than splints.^4,6

The main disadvantage of this fixation method is that dental roots may be damaged during screw insertion. In contrast with other published studies, drilling was not used in our series because bone screws were self-tapping. If a selftapping screw is not positioned between two roots, the surgeon immediately notices resistance and can change direction. Root position was visualized before screw insertion by examining the panoramic radiograph. Crowding and impacted or supernumerary teeth were carefully avoided. Although there are many radiographs in which a screw seems to be in contact with the dental root, there are few instances of complications⁷ or of clinically relevant complications.

Screw loss before extraction,^2,4 loss of teeth adjacent to screws, and screw fracture⁸ are complications that have been reported in the literature.

Inserting the screw between adhered gum and movable gum is the best way to prevent encroachment of the oral mucosa on the screw head.^4,6 Unencumbered screws can be removed without using anesthesia.

Maxillomandibular fixation with bone screws is not indicated when elastic band traction is needed to correct malocclusion, ^4,8 in comminute fractures, or in children with deciduous or intermediate tooth eruption.^4,7

 

Conclusions

Bone screws for maxillomandibular fixation are a valid alternative to the classic fixation technique with splints and wires. This technique reduces operating time, improves patient tolerance, facilitates oral hygiene, is less traumatic to the dental papilla and oral mucosa, and diminishes the risk of accidental pricks and contagious disease transmission to surgeons. Most importantly, the rate of dental injury is low (0.8%). The surgeon’s skill is the best guarantee for avoiding complications like root injury or bone screw fracture.

At the end of this retrospective study, we observed that the number of patients who required elastic traction to correct postoperative malocclusion was minimal. One option for reducing complications derived from the presence of intraoral screws (overgrowth of the screw head by oral mucosa, patient discomfort, and other) is to remove screws when the jaw fracture does not require postoperative fixation or when the postoperative reduction and stabilization of the fracture focus is good.

 

 

Correspondence:
Dr. Javier Gonzalez Lagunas
Hospital Universitario Vall d’Hebrón
08035 Barcelona, España
Email glagunas@terra.es

Recibido: 18.12.06
Aceptado: 16.06.08

 

 

References

1. Arthur G, Berardo N. A simplified technique of maxillomandibular fixation. J Oral Maxillofac Surg 1989;47:1234.        [ Links ]

2. Karlis V, Glickman R. An alternative to arch-bar maxillomandibular fixation. Plast Reconstr Surg 1997;99:1758-9.        [ Links ]

3. Maurer P, Syska E, Eckert AW, Berginski M, Schubert J. The FAMI screw for temporary intermaxillary fixation. Mund Kiefer Gesichtschir 2002;6:360-2.        [ Links ]

4. Roccia F, Tavolaccini A, Dell’acqua A, Fasolis M. An audit of mandibular fractures treated by intermaxillary fixation using intraoral cortical bone screws. J of Cranio-Maxillofac Surg 2005;33:251-4.        [ Links ]

5. Imazawa T, Komuro Y, Inoue M, Yanai A. Mandibular fractures treated with maxillomandibular fixation screws. J Craniofac Surg 2006;17:544-9.        [ Links ]

6. Gordon KF, Read JM, Anand VK: Results of intraoral cortical bone screw fixation technique for mandibular fractures. Otolaryngol Head Neck Surg 1995;113:248-52.        [ Links ]

7. Fabbroni G, Aabed S, Mizen K, Starr DG: Transalveolar screws and the incidence of dental damage: a prospective study. Int J Oral Maxillofac Surg 2004;33:442-6.        [ Links ]

8. Coburn DG, Kennedy DWG, Hodder SC. Complications with intermaxillary fixation screws in the management of fractured mandibles. Br J Oral Maxillofac Surg 2002;40:241-3.        [ Links ]