November, 2011

A New protocol for Emergency Orthodontic Care

Avesh Sachan , BDS,MDS
Senior Resident
Department of Orthodontics
Faculty of dental sciences
IMS ,B.H.U.
Varanasi.

T.P.Chaturvedi, BDS, MDS
Professor
Department of Orthodontics
Faculty of dental sciences
IMS, B.H.U
Varanasi.

Corresponding   Author-

Dr.  Avesh Sachan
Senior Resident
Department of Orthodontics   
Faculty of dental sciences
Institute of Medical Sciences
Banaras Hindu University
Varanasi – 221005, U.P.(India)

E-mail- dr.aveshsachan@gmail.com

Abstract

Orthodontic appliances or parts of orthodonticappliances have caused problems for the patients and orthodontists. Some are less severe like Discomfort, Mouth Sores and Irritation of Lips or Cheeks to more severe problems like Swallowing or Aspiration of appliances or its parts. The type of appliances that have causedproblems and their clinical management are discussed. Suggestions are made to try and avoid theproblems that were encountered in the literature in patients undergoing orthodontic treatment.

 

Key words – Irritation of Lips or Cheeks, Loose Bands, Displaced or broken arch wires, fixed functional appliance, headgear injury, Quad Helix, Micro implants, Appliance  Swallowed/Aspirated.

 

Introduction

Orthodontic appliances, either Removable or Fixed are delicate and must be taken care of in order to prevent damage to them. Patients should be instructed to always be careful with what they  eat and their  activities to prevent  breaking any of appliances or its parts¹. Sometimes, however, things happen and something breaks. It is important to know what to do. Only the most severe emergencies may require immediate attention by the orthodontist². The following are some of the common problems that occur and what to do about them.

Discomfort and Mouth Sores

It’s normal to have discomfort for up to seven days after braces or retainers are placed or adjusted. Although temporary, it can make eating uncomfortable³ (fig-1).

     

 

Encourage soft foods.  Have the patient rinse the mouth with warm salt water⁴.  Over-the-counter pain relievers, acetaminophen or ibuprofen, may also be effective⁵. Patient who has mouth sores during orthodontic treatment may gain relief by applying a small amount of topical anesthetic gel directly to the sore area using a cotton swab.  Reapply as needed.

Irritation of Lips or Cheeks

Lips or cheeks may be irritated by loops or spurs on the archwire^6,7,8. The parotid papilla is particularly susceptible to appliance irritation and every attempt should be made to round all surfaces in contact with lips or cheeks. Steel ligature ties used for holding archwires to brackets are made in such a manner that the twisted pigtail is left to be tucked under the archwire. These pigtails may be dislodged by mastication that may not have been tucked in sufficiently¹. Emergency appointments involve nothing more than tucking the pigtail back to stop the irritation of gingival or mucosa of lips or cheeks⁹.

Sometimes new braces can be irritating to the mouth.  A small amount of orthodontic wax makes an excellent buffer between the braces and lips, cheeks or tongue^10,11,12(fig-2, fig-3).

              

                                               

Simply pinch off a small piece and roll it into a ball the size of a small pea.  Flatten the ball and  place   it completely over the area of the braces causing irritation¹³. If possible, dry off the area first so that the wax will stick better. The patient may then eat more comfortably. If the wax is accidentally swallowed it’s not a problem. The wax is harmless.
Loose Bands           

All loose bands should be carefully removed. The tooth should be pumiced and all debris removed. A band that has worked loose, often needs modification¹⁴. The band should be placed exactly where it should be on the tooth so that the bracket or buccal tube should be in optimal position for proper tooth control.  Sometimes a band that fits well and requires no modification becomes loose (fig-4,fig-5).

In this case, the band may be washed with soap and water, sterilized in alcohol and dried. Teeth are then isolated and the band recemented. A piece of tin or aluminum foil should be adapted to prevent contamination. Excess cement may be removed.

Some patients complain of soreness in a particular area not knowing the band is loose because the band is tied into the archwire. The loose band moves occluso-gingivally during mastication, lacerating periodontal tissues and causing considerable soft tissue irritation¹. In this case, after band removal, do not recement the band immediately .Saline rinses for a couple of days will permit recovery and healing of the gingival mucosa.

Displaced or Broken Archwires

This is very common, a hard or sticky food has dislodged the archwire from the buccal tube on the molar and the patient comes in with end of wire sticking into the cheek¹(fig-6,fig-7).

 

         

                                                   

 

Displaced or broken archwires may allow unaccounted forces to cause quite considerable improper tooth movement and tissue damage if the patient is not seen immediately to remove the active fragment.

An archwire that has been dislodged can usually be replaced into the buccal tube by temporarily deforming the wire and then straightening it with a plier after the ends has been reinserted back into the buccal tube. Occasionally, there is a cheek irritation at the distal end of the archwire. It is wise to see that the end of the archwire is turned in sharply towards the gingival or at least rounded off so that it poses no threat.

 

Breakages of Fixed Functional Appliances:

Fixed functional appliances are designed to provide a simple non-compliant solution to orthodontic Class II treatment. Molar correction can be achieved very quickly using these appliances^15,16, but the clinician should be wary of unexpected breakages¹⁷. These appliances remove the need for a patient to comply, but when faced with constant repair and monitoring of breakages, they may instead transfer the compliance to the practitioner¹⁸.

If the Herbst appliance comes apart when opening your mouth too wide, slip the rods back into the pistons. Patient should be advised to support his/her chin when yawning and to avoid any activity that would cause to open his/her mouth wide to prevent breakage of fixed functional appliance. If the appliance breaks, please call the orthodontist to schedule a repair appointment.

Injury from Orthodontic Headgear

The child should place and remove the headgear under supervision several times to be certain that he or she understands how to manipulate it and to ensure proper adjustment. Most headgear is worn after school, during relaxed evening hours and during sleep. It is definitely not indicated for vigorous activity, bicycle riding, or general roughhousing⁵. Children should be instructed that if anyone grabs the outer bow, they should also grab the bow with their hands. This will prevent breakage and injury. The headgear straps must be equipped with a safety-release mechanism to prevent the bow from springing back at the child and injuring him or her if it is grabbed and pulled by a playmate¹⁹.Disengagement of extraoral traction (headgear) may cause a variety of injuries to the eyes, eyelids, nose, and related areas. Total blindness is the most severe result reported so far^{20,21,22,23,24,25}.

It should be remembered that the infraorbital space infection may lead to a cavernous sinus thrombosis by penetration of the angular vein. Cavernous sinus thromboses are most often fatal but may resolve with severe morbidity, such as blindness or brain damage^26,27. Prompt and definitive treatment should be administrated to prevent these consequences.

Verbal and written instructions should be given routinely and safety devices should be considered. If any infraorbital injury occurs, the patient should be instructed to contact the orthodontist immediately and refer for a maxillofacial surgeon’s examination. These injuries may be asymptomatic initially but exacerbate later. Immediate antibiotic therapy active against oral aerobic and anaerobic flora after incision and drainage may prevent a fatal outcome^28,29,30.

Removable Appliances or Retainers

On removable appliances the attached wire are frequently bent out and loops or clasps will impinge on gingival tissue^31,32,33. Wire appurtenances should be checked carefully to make sure nothing is broken and adjusted so that they lie in close proximity to tissue. Frequently the labial bows of removable appliances are broken, most often at junction of acrylic and wire¹(fig-8).Temporary repair may be done fairly easily without burning the acrylic.

Breakages of Quad Helix/Lingual Arch/Nance or Transpalatal Arch

 

A lingual arch space maintainer is usually soldered to the molar bands but can be removable, depending on the number of adjustments anticipated and the care of the appliance expected from the patient. Removable lingual arches (e.g., that  fit in to attachments welded onto the bands) are more prone to breakage and loss. The most common problems with lingual arches are distortion, breakage and loss⁵. Careful instructions to parents and patients can reduce these problems.

 

W-arch and the quad helix leave an imprint on the tongue, about which the parents and child should be warned. This will disappear when the appliance is removed. The greatest problems are distortion and breakage from poor patient cooperation and poor oral hygiene, which can lead to decalcification and decay. Patients are advised to avoid sticky hard foods as these might break the quad helix. Thorough, but careful, brushing around the appliance is important to keep it and the teeth clean and free from cavities¹. Certain areas of the quad helix or bands to which it attaches might bother cheeks and tongue at first. This usually goes away after a few days, but the use of wax or wet cotton balls will help to minimize the discomfort while mouth is adjusting. Rinsing with warm salt water will help bothered areas feel better and return to normal. It is better to call the orthodontist immediately if anything feels loose or broken.

 

Failure of temporary anchorage devices

Mini-implants are effective as anchorage, and their success depends on proper initial mechanical stability and loading quality and quantity^34,35. To minimize the failure of screw implants, inflammation around the implant must be controlled (fig-9).

 

We suggest that this sufficient amount of cortical bone at the initial stage of healing enables the immediate loading in miniscrews to resist against orthodontic forces^36,37,38,39. Furthermore, less amount of cortical bone formed at the head of the miniscrew may be one reason for the higher failure rate in the mandible^40,41.

To minimize root contacts, micro implants need to be inclined distally about 10 to 20 degrees and placed 0.5 to 2.7mm distally to the contact point to minimize root contact according to sites and levels⁴², except into palatal interradicular bone between the maxillary first and second molars (fig-10).

 

 

Screws of 1.2-mm diameter and at least 8-mm length are preferable, because they are stable and minimize the risk of root damage. The maxilla was shown to be better suited for miniscrews⁴³.

Micro implant has a failure rate of 5~25% depending on the technique, patients’ type, insertion sites, and usually more failure occurs on mandible rather than maxilla. The patients should be fully informed with the possibility of failure before starting micro implants. Failures can be mainly immediate or delayed. Failures can be categories in to 3 types as shown in table-1.

 

 

Table-1: Factors responsible for failure of temporary anchorage devices.

 

Patient  related Factors	Operator related Factors	Implant related Factors
Systemic disorder in patient Smoking habit/ mouth breathing Poor quality of bone Excessive thickness of mucosa Quality of gingival/ perio tissue Poor oral hygiene maintenance Medications like anti epilepsy Radiotherapy Diabetes, Osteoporosis Site related, more failure in mandible	Faulty surgical procedure Self drilling technique is better Proper angulation of Implant Excessive heat generation Large hole during drill use Aseptic technique Damage to root or nerve tissue	Proper choice of implant length and diameter Smaller than 8 mm fail more Distortion during placement Placement in keratinized gingiva is better when possible Use miniplates when anchorage requirement is heavy Titanium screws are better, you can easily bond composite on them Excessive force application

 

 

 

Appliance or Piece of Appliance is Swallowed/Aspirated

Sometimes orthodontic appliances or parts of them can blockthe airway and gastrointestinal tract due to the close proximityof these appliances to the oro-pharynx. The presence of any foreign body in the airway needs to be treatedas a serious situation as it can be a cause of accidental death⁴⁴. Foreign bodies entering the alimentarycanal do not represent a serious medical problem unlessthey become impacted or cause perforation of the gut wall asthe majority pass through without incidence^45,46. The incidence of reported casesof aspiration or ingestion of orthodontic appliances include swallowing of a transpalatal arch during its removal⁴⁷, a lower spring retainer⁴⁸,an upper removable appliance⁴⁹ , a fragmentof an upper removable appliance⁵⁰, a piece ofarchwire⁵¹ , and expansion appliance keys⁵².

 If an object is dropped into the mouth in a supine patient, then eitherthe patient’s head should be turned to one side to encouragethe object to fall into the cheek and not the oropharynx⁵³  or the patient could be turned face down to allowthe object to fall out of the mouth^54,55. The patient should be askedto cough⁵⁶. The mouth and oropharynxshould be examined carefully, and if the object is visible it should beremoved either with forcepsor high speed suction^56,57.

Most foreign bodies entering the oropharynx willpass into the alimentary canal⁴⁵ and passwithout incidence, though there is a danger of perforation ofthe gut which can have very serious consequences including death⁴⁶. In the esophagus, only large objectsand those with sharp edges are liable to become impacted. Common Symptoms of esophageal obstructionare the inability to swallow, muscle incoordination, pain onswallowing, hematemesis, or vomiting. Once a foreign body hasreached the stomach it has an 80–90 per cent chance ofpassing along the gut without problems^45,46,48.

Treatment of aspirated foreign bodies is dependent on the severityof the signs and symptoms. If the foreign body is obstructive and thepatient is in respiratory distress, dislodgement of the foreignbody should be initially attempted with back blows and the Heimlichmaneuver^56,58,59. If these fail to dislodge the object, then positive airwaypressure needs to be maintained by artificial respiration andif this fails to maintain a patent airway, the object shouldbe bypassed and an emergency airway established⁶⁰.

If the object has passed the vocal cords and there is no obstructionof the airway, the patient should still be referred for immediatemedical attention^48,61. All foreignobjects in the respiratory track need removal and this shouldbe done as soon as possible as edema, excessive secretionsand formation of granulation tissue can make localization andremoval difficult^57,62.The mucosal appearance of the pink acrylic often used in orthodonticscan also make visualization during bronchoscopy of any fragmentof inhaled acrylic difficult and, hence, may complicate itsremoval^63.64 .

In some patients, placing molar bands can be difficult, especiallysecond molar bands. To help keep control of bands in these patientsand to aid quick retrieval, floss can be tied through the tube. Once the band is cementedon the tooth, the floss can be removed. Auxilliaries that are placed on archwires such as coilsprings can be temporarily stabilized on the wire during itsplacement with wax.

All the components of removable appliances should be smoothand rounded as far as possible. All cribs or springs shouldnot have any sharp ends, and finger springs and stops should berounded⁶⁵. Hooked or‘C’ clasps should be avoided if possible, or alternativeretentive components used. This will reduce the risk of puncturingor irritating the lining of the alimentary canal, and make retrievalwithout further damage. The use of different coloredacrylics, rather than pink, for the construction of removableappliances and retainers has been suggested to avoid problemsvisualizing the acrylic on bronchoscopy or endoscopy if fragmentsare inhaled or swallowed⁶⁶. Patients should always be advised at the time of appliance placement thatthey should not try to reinsert damaged, ill-fitting, or brokenfragments of any appliance. They should stop using them, andcontact the Orthodontist to have the appliancechecked⁶⁷.

Keys for turning fixed expansion appliances (R.M.E.) intra-orally shouldbe attached to floss and  any open contact on the handle of thekey should be soldered to prevent the floss from slipping throughthe handle⁵². An alternative key thatis attached to a plastic spatula is  now commercially availableand may be a preferable alternative (fig-11,fig-12,fig-13).

                                   

                     

 

  

When fitting or removing transpalatal arches and quadhelices,it may be advisable to have a long length of floss tied to theappliance attached via a closed loop on the appliance to avoidits inhalation or swallowing.  

When cutting the ends of archwires with safety distal end wirecutters, the pliers sometimes fail to hold the cut fragment.A cotton wool roll placed over the end of the archwire beforeit is cut will prevent the piece of archwire becoming displacedin the mouth, or embedded in the soft tissues of the patient^55,68. All orthodontic instruments shouldbe inspected for signs of failure, and replaced orreconditioned on a regular basis⁵⁵.

During the taking of impressions the impression material used should have a high viscosity and the tray should be the correctsize and fit⁵³. The clinician should be able to visualize the back of the uppertray as it is seated in the mouth so excess impression materialis not allowed to extrude into the back of the mouth. The patientshould then be advised to tilt the head forward, place theirchin down towards the chest, avoid trying to swallow, and ifnecessary dribble onto a bib placed on their chest. The patientmay find it more comfortable to breath through their mouth,rather than their nose while the impression is seated in themouth.

 If a piece of appliance is dropped in the mouth during treatment,the availability of high speed suction with a pharyngeal tipcan help with quick retrieval.The use of a radio-opaque acrylic has beenrecommended extensively in the literature over a considerableperiod of time for use in dental appliances to aid the detectionof acrylic fragments if aspiration or ingestion occurs⁶⁹ .Most acrylicsare radiolucent which makes it difficult to locate the acrylicif it is inhaled or ingested with plain radiography.

 

Conclusions

Patients may be able to temporarily solve many problems themselves until the patient’s regularly scheduled appointment. After alleviating discomfort, it is very important that the patient reports to the orthodontist as soon as possible to schedule a time to repair the problem. Allowing an appliance to remain damaged for an extended period of time may result in disruptions in the treatment plan. Some more severe emergencies like Swallowing or Aspiration of appliances or its parts may require immediate attention by the orthodontist.

 

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