Ann Otol Rhinol LaryngollOl:1992
NEW DEVICE FOR INTERDENTAL IMMOBILIZATION BORIS O. DIVIS, MD, FRCSC CAMPBELL RIvER, CANADA
The immobilization ofa simple fractured jaw with arch bars isa time-consuming, laborious procedure. The alternative method of immobilization described here uses aprecisely threaded, 22-gauge, malleable stainless steel wire and athreaded nylon nut. Itaffords the surgeon relative safety from accidental puncture trauma and makes the interdental immobilization a precise and speedy procedure. KEY WORDS - alternative, arch bar, interdental immobilization, jawfracture. tient, retightening carries a constant danger of wire breakage and possibly a need for further anesthesia and surgery to replace the wires. Dimac wires are a simple and speedy alternative, providing greater safety to both the patient and the surgeon. Each wire is made of 22-gauge malleable stainless steel that is threaded at one end and fitted with a threaded nylon nut that has a concave upper surface (Fig 2). There are 167 precision-cut threads per inch on the wire, and each full tum of the threaded nylon nut represents 0.152 mm (0.006 in) of movement along the wire. It is the precise cutting of the thread on the wire and the nut that is the heart of the system. It allows the surgeon to feel the tightness of the wire around the tooth and eliminates the chance of avulsion. The pressure of the nylon nut against the hooked wire sustains this tightness and provides stability. Only one tooth is required to create a wiring post, but there must be opposing dentition.
The Dimac wire (US Food and Drug Administration No. K910090; Dimac Medical Inc, Blaine, Wash) was developed as a simple and precise method of jaw immobilization that would afford greater safety to both the patient and the surgeon. It satisfies the surgical demands for simplicity of design and simplicity of application, while allowing direct observation of the dental occlusion (Fig 1). Today, the common method of immobilizing a simple fracture with good dentition is by the application of Ivy loops or arch bars wired to individual teeth. Unfortunately, these are tedious and timeconsuming methods, with the constant danger of trauma to the surgeon's fingers through the twisted wire ends, which need to be tucked away after they are trimmed. Twisting a wire around a tooth conveys very little information as to its tightness, and so there is a danger of avulsion if the pressure is too great. To quote Wilson and Hohmann 1(p430-1) from a paper on dental anatomy and occlusion, The structures responsible for maintaining the stability of the tooth are the gingiva, periodontal membrane, cementum and alveolar bone. which collectively are called the periodontium. It is obvious that during surgical procedures every effort must bemade topreserve these supporting tissues. Damage tothese structures may later result in tooth loss. For these reasons special precautions must be taken inthe application ofarch bars. All too frequently a large (number 24 or 26) wire is forced through the soft tissues ofthe interdental space. The tightening ofthis wire around atooth may cause ischemic necrosis ofthe mucosa. periodontal membrane, and transverse fibers. Ifdamage is extensive, tooth loss may result. It ismuch less traumatic to employ a loop of number 28 wire. which is passed around the tooth ona loop ofdental floss•... This gauge (28) calls for the application of a greater number of wires (16 or more), with increased likelihood of breakage, a longer operating time, and a greater chance of puncture trauma to the surgeon. If the wires are not sufficiently tight around the tooth at the time of operation, they will loosen and require retightening. Besides being unpleasant for the paREPRINTS -
A further safety feature of the apparatus lies in the design, which uses nylon for the nut, causing it to strip if the pressure is too great. If this should happen, the wire remains in place and only the nut has to be replaced.
Fig I. Dimac wires and interdental wiring inplace.
Boris O. Divis, MD, FRCSC, Suite 414, 1180 Ironwood St, Campbell River, British Columbia V9W SP7, Canada.
776
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on August 5, 2015
Divis, Interdental Immobilization
777
and personnel. Besides being used to provide intermaxillary fixation for simple jaw fractures with good dentition, Dimac wires may be used intraoperatively or postoperatively in orthognathic surgery, temporomandibular joint surgery, jaw resection, and plating procedures. They also allow horizontal stabilization ofjaw fractures by the application of interdental wires across adjoining teeth.
Fig 2. Close-up view of Dimac wire and nut showing precisely cut thread on wire and concavity of nut.
The wire is applied by being passed between adjoining teeth from buccal to lingual and back to the buccal surface through the next interdental space, encircling the tooth (Fig 3A). After the nylon nut is snugged against the teeth, it is unwound approximately 10 turns, and the distal end of the wire is brought medially and clockwise around the proximal end. It is then turned sharply on itself to create a tight hook, and the excess wire is snipped off(Fig 3B). The nut is then tightened down, and any excess wire protruding through the center of the nut is trimmed off in the concavity so that it does not irritate the mucosa. Because it is applied at right angles to the tooth, the wire remains firmly applied and does not loosen. Up to eight wires may be used to immobilize ajaw, with a greatly reduced application time. Specifically, the 1 to 2 hours required for arch bar application is reduced to 20 to 40 minutes for Dimac wires providing economy in the use of operating room time
Postoperative adjustment is minimal and, if needed, requires only a fractional tum of the nut. There is no wire breakage or discomfort to the patient, as can happen with the postoperative adjustment of arch bars. Removal of the wires is possible without anesthesia and consists of unscrewing the nylon nut and unhooking the loop of wire, which is then clipped off close to the tooth. The remaining wire is pushed backward and removed from the lingual aspect of the tooth (Fig 3C). In 30 cases of simple jaw fractures with good dentition that were treated with this method of fixation, one patient required a wire to be tightened by a quarter tum of the nut. Two patients complained of irritation of the mucosa, and this was cured by the application of dental wax. In all cases there was minimal damage to the gingiva at the time of removal of the wires, with return to normal appearance within a week. None of the patients suffered damage to their teeth. Dimac wires are manufactured in the United States and are sold in sets of 10 wires, including a nut driver, for $79.
SNIP
A
c
B
Fig 3. Procedure. A) Pass wire between adjoining teeth from buccal to lingual and back to buccal surface through next interdental space to encircle tooth. B) Snug nut against teeth and unwind it approximately 10 turns. Bring distal end of wire medially and clockwise around proximal end. Tum it sharply on itself. tighten down nut, and snip off any excess wire in concavity. C) To remove wire, unscrew nut and unhook loop of wire. Snip off close to teeth. Push remaining wire backward and remove from lingual aspect.
REFERENCE 1. Wilson KS, Hohmann A. Dental anatomy and occlusion. Otolaryngol Clin North Am 1976;9:425-38.
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on August 5, 2015
NEW DEVICE FOR INTERDENTAL IMMOBILIZATION BORIS O. DIVIS, MD, FRCSC CAMPBELL RIvER, CANADA
The immobilization ofa simple fractured jaw with arch bars isa time-consuming, laborious procedure. The alternative method of immobilization described here uses aprecisely threaded, 22-gauge, malleable stainless steel wire and athreaded nylon nut. Itaffords the surgeon relative safety from accidental puncture trauma and makes the interdental immobilization a precise and speedy procedure. KEY WORDS - alternative, arch bar, interdental immobilization, jawfracture. tient, retightening carries a constant danger of wire breakage and possibly a need for further anesthesia and surgery to replace the wires. Dimac wires are a simple and speedy alternative, providing greater safety to both the patient and the surgeon. Each wire is made of 22-gauge malleable stainless steel that is threaded at one end and fitted with a threaded nylon nut that has a concave upper surface (Fig 2). There are 167 precision-cut threads per inch on the wire, and each full tum of the threaded nylon nut represents 0.152 mm (0.006 in) of movement along the wire. It is the precise cutting of the thread on the wire and the nut that is the heart of the system. It allows the surgeon to feel the tightness of the wire around the tooth and eliminates the chance of avulsion. The pressure of the nylon nut against the hooked wire sustains this tightness and provides stability. Only one tooth is required to create a wiring post, but there must be opposing dentition.
The Dimac wire (US Food and Drug Administration No. K910090; Dimac Medical Inc, Blaine, Wash) was developed as a simple and precise method of jaw immobilization that would afford greater safety to both the patient and the surgeon. It satisfies the surgical demands for simplicity of design and simplicity of application, while allowing direct observation of the dental occlusion (Fig 1). Today, the common method of immobilizing a simple fracture with good dentition is by the application of Ivy loops or arch bars wired to individual teeth. Unfortunately, these are tedious and timeconsuming methods, with the constant danger of trauma to the surgeon's fingers through the twisted wire ends, which need to be tucked away after they are trimmed. Twisting a wire around a tooth conveys very little information as to its tightness, and so there is a danger of avulsion if the pressure is too great. To quote Wilson and Hohmann 1(p430-1) from a paper on dental anatomy and occlusion, The structures responsible for maintaining the stability of the tooth are the gingiva, periodontal membrane, cementum and alveolar bone. which collectively are called the periodontium. It is obvious that during surgical procedures every effort must bemade topreserve these supporting tissues. Damage tothese structures may later result in tooth loss. For these reasons special precautions must be taken inthe application ofarch bars. All too frequently a large (number 24 or 26) wire is forced through the soft tissues ofthe interdental space. The tightening ofthis wire around atooth may cause ischemic necrosis ofthe mucosa. periodontal membrane, and transverse fibers. Ifdamage is extensive, tooth loss may result. It ismuch less traumatic to employ a loop of number 28 wire. which is passed around the tooth ona loop ofdental floss•... This gauge (28) calls for the application of a greater number of wires (16 or more), with increased likelihood of breakage, a longer operating time, and a greater chance of puncture trauma to the surgeon. If the wires are not sufficiently tight around the tooth at the time of operation, they will loosen and require retightening. Besides being unpleasant for the paREPRINTS -
A further safety feature of the apparatus lies in the design, which uses nylon for the nut, causing it to strip if the pressure is too great. If this should happen, the wire remains in place and only the nut has to be replaced.
Fig I. Dimac wires and interdental wiring inplace.
Boris O. Divis, MD, FRCSC, Suite 414, 1180 Ironwood St, Campbell River, British Columbia V9W SP7, Canada.
776
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on August 5, 2015
Divis, Interdental Immobilization
777
and personnel. Besides being used to provide intermaxillary fixation for simple jaw fractures with good dentition, Dimac wires may be used intraoperatively or postoperatively in orthognathic surgery, temporomandibular joint surgery, jaw resection, and plating procedures. They also allow horizontal stabilization ofjaw fractures by the application of interdental wires across adjoining teeth.
Fig 2. Close-up view of Dimac wire and nut showing precisely cut thread on wire and concavity of nut.
The wire is applied by being passed between adjoining teeth from buccal to lingual and back to the buccal surface through the next interdental space, encircling the tooth (Fig 3A). After the nylon nut is snugged against the teeth, it is unwound approximately 10 turns, and the distal end of the wire is brought medially and clockwise around the proximal end. It is then turned sharply on itself to create a tight hook, and the excess wire is snipped off(Fig 3B). The nut is then tightened down, and any excess wire protruding through the center of the nut is trimmed off in the concavity so that it does not irritate the mucosa. Because it is applied at right angles to the tooth, the wire remains firmly applied and does not loosen. Up to eight wires may be used to immobilize ajaw, with a greatly reduced application time. Specifically, the 1 to 2 hours required for arch bar application is reduced to 20 to 40 minutes for Dimac wires providing economy in the use of operating room time
Postoperative adjustment is minimal and, if needed, requires only a fractional tum of the nut. There is no wire breakage or discomfort to the patient, as can happen with the postoperative adjustment of arch bars. Removal of the wires is possible without anesthesia and consists of unscrewing the nylon nut and unhooking the loop of wire, which is then clipped off close to the tooth. The remaining wire is pushed backward and removed from the lingual aspect of the tooth (Fig 3C). In 30 cases of simple jaw fractures with good dentition that were treated with this method of fixation, one patient required a wire to be tightened by a quarter tum of the nut. Two patients complained of irritation of the mucosa, and this was cured by the application of dental wax. In all cases there was minimal damage to the gingiva at the time of removal of the wires, with return to normal appearance within a week. None of the patients suffered damage to their teeth. Dimac wires are manufactured in the United States and are sold in sets of 10 wires, including a nut driver, for $79.
SNIP
A
c
B
Fig 3. Procedure. A) Pass wire between adjoining teeth from buccal to lingual and back to buccal surface through next interdental space to encircle tooth. B) Snug nut against teeth and unwind it approximately 10 turns. Bring distal end of wire medially and clockwise around proximal end. Tum it sharply on itself. tighten down nut, and snip off any excess wire in concavity. C) To remove wire, unscrew nut and unhook loop of wire. Snip off close to teeth. Push remaining wire backward and remove from lingual aspect.
REFERENCE 1. Wilson KS, Hohmann A. Dental anatomy and occlusion. Otolaryngol Clin North Am 1976;9:425-38.
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on August 5, 2015
