AbstractThe objective was to assess the timing of referrals ofectopic maxillary canines, to determine at what age these patients were beingreferred and to determine if these referrals comply with theguidelines by the Royal College of Surgeons of England.
The design was a retrospectiveclinical audit. Data was collected from clinical notes of patients on thejoint-clinic waiting list in the University Dental Hospital in Cardiff. Datawas collected for 52 patients with canine ectopia on the waiting list duringJune 2017. The ‘gold’ standard as stated by Royal College of Surgeons ofEngland titled Management of the Palatally Ectopic Maxillary Canine publishedin 2016 states that all patients with an ectopic canine should be referred bythe age of 12 years.
Patients’ data was compared to this standard. Of the 52patients, 17.3% were referred by the age of 12, meaning 82.7% were referredlate (>12 years). The mean age of referral was 14.9 years of age.
It wasconcluded that patients are referred late when compared with the guidelinespublished by the Royal College of Surgeons.IntroductionTooth eruption usually occurs by a process in which a formingtooth migrates from its intraosseous position to a position that allowsfunction within the oral cavity. (Yaseen, Naik and Uloopi, 2011) An ectopictooth can be defined as a tooth that follows an abnormal eruption path whilstimpaction is when a tooth is unable to erupt without interception. This iscommonly associated with an ectopic path of eruption.
(Michael, 2011) Thepermanent maxillary canine is the most frequent tooth to be impacted with theexception of the mandibular third molar. The frequency of maxillary canineimpaction varies from 0.8 to 2.8 percent and is more than twice as common infemales. 85 percent of these teeth are found palatally and the remaining 15percent are found bucally. (McSherry, 1998) 8 percent of canine impactions arebilateral. The incidence of impaction of the canine is twice as common in themaxilla as the mandible. (Litsas, 2011)Generally, causes of delayed eruption can be categorised into generalised and localised factors.
Generalised causes include irradiation, deficiencyof nutrients, genetic disorders and endocrine diseases. Localised factors arecommonly due to physical obstructions. These obstructions can be supernumeraryteeth or a tumour for example.
Mucosal barriers may be an important factor.Failure of fusion between a developing follicle and the mucosa results infailure of mucosal breakdown and can prevent eruption. Supernumerary teeth cancause delayed eruption, displacement and crowding. (Peedikayil, 2011) Toothsize-arch length discrepancies, early loss or prolonged retention of thedeciduous canine, ankyloses, dilacerations of the root, abnormal tooth-budposition and idiopathic conditions can lead to ectopic position of the canine,however, the aetiology is likely to be multifactorial (Bishara and Ortho.,1992). The maxillary canine has the longest eruption path of all teeth in thepermanent dentition and this may contribute to the aetiology. (McSherry, 1998)Two theories are commonly used to attempt to explain theoccurrence of palatally ectopic canines. These are the ‘guidance theory’ andthe ‘genetic theory’.
Guidance theory proposes that the canine, when erupting,does not have the guide usually formed by the distal surface of theneighbouring lateral incisor during the eruption pathway. The lack of guide iseither due to a hypoplastic or missing lateral incisor. This theory issupported by the fact that in the presence of peg-shaped and missing laterals,palatally positioned canines are frequently found. (Litsas, 2011) It has beenstated by Brin, Becker and Zilberman, 1993, that there is a direct cause andeffect relationship between missing or peg-shaped lateral incisors andpalatally placed maxillary canines. The alternative theory, genetic theory,states that the abnormality in eruption of the maxillary canine is as a resultof developmental disturbances of the dental lamina. The variation in frequency betweensexes, bilateral occurrences and familial occurrences may support the idea thatgenetics have an important role in canine eruption. Other significant dentalfindings such as agenesis of molars and premolars are more commonly found inthose individuals with ectopic canines, also supporting the theory. (Peck, Peckand Kataja, 1996) Discrepancies in tooth-arch length are usually responsiblefor buccally impacted canines.
It was shown in a study that in only 17 percentof bucally impacted canines there was sufficient space, compared to palatallyimpacted canines, where 85 percent of cases had sufficient space for eruption.(Jacoby, 1983)There are a number of risks associated with ectopic canines. Themain risk from ectopic canines appears to be root resorption of adjacent teeth,most commonly the neighbouring lateral incisor. In one study (Walker, Encisoand Mah, 2005) with use of cone-beam computed tomography, it was found that 66.7percent of lateral incisors neighbouring an impacted maxillary canines and 11.1percent of central incisors had some resorption. Other sequelae includemigration of neighbouring teeth, loss of arch length, dentigerous cystformation, internal resorption, referred pain, infection especially in thosepartially erupted, and a combination of those listed. (Bishara and Ortho.
,1992) On top of these, aesthetics can be a concern for many patients., however,the presence of an impacted canine may cause no concern or pathology during awhole lifetime but due to the range of potential risks it is important that thecanines of the developing child should be monitored carefully to detect any abnormalitiesand if required, interception of the ectopic canine can then be carried out asearly as possible. Patients will very often not be aware that there are anyissues associated with their canines and so therefore general dentalpractitioners (GDPs) are in an ideal position to detect an ectopic canine earlyand refer appropriately.
The Royal College of Surgeons guidelines ‘Managementof the Palatally Ectopic Maxillary Canine’ state that all patients with animpacted canine should be referred by the age of 12 years. (Husain, Burden andMcSherry, 2016)All GDPs should, as part of a general examination, palpatefor a canine bulge in patients from the age of 10 years. The BritishOrthodontic Society states that a favourable canine is usually palpable by theage of 10-11. (Managing the developing dentition, 2010) If not palpable, anectopic canine should be suspected and a thorough assessment of the malocclusionshould be undertaken, including canine localisation.
Radiographic examinationcan aid localisation of the canine and the parallax technique can beparticularly useful in assisting in locating the tooth. The retained deciduouscanines should always be assessed for mobility. A firm canine indicates thatthe permanent successor has delayed development or there is a failure ofresorption of the deciduous canine by this successor. Mobility, discolorationor loss of vitality of neighbouring incisors may be due to pressure from anectopic canine. The presence of lateral incisor tipping may be due to pressureplaced on the root by an ectopic canine. (Mittal, Murray and Sandler, 2012)Treatment of an ectopic canine depends on a number of factorsincluding age and position of the tooth.
These treatments range from surgicalexposure and orthodontic alignment to surgical removal of the ectopic canine.In some cases, the canine can be left and carefully observed. If detected earlyenough, in selected cases interceptive extraction of the deciduous canine canresult in an improvement in the position of the ectopic permanent canine. Thepatient should be aged between 10 and 13 years. This is a relatively simple,cost effective method of correcting the malocclusion. (Husain, Burden andMcSherry, 2016) A study by Sune Ericson and Juri Kurol (Ericson and Kurol,1988) analysed the effect of extraction of the primary canine on palatallyerupting maxillary canines. In this study it was found that 78 percent of thepalatally erupting teeth changed to a normal eruption path after 18 monthsalthough success reduced as the degree of malposition increased. The authorssuggested that in children aged 10-13, extraction of the primary canine is thetreatment of choice to correct palatally ectopic canines provided that there issufficient space and no pathology found.
They recommended that in laterdiagnosis or those with associated pathology, alternative treatment should beconsidered. Another study by Power and Short seemed to confirm these findingsbut they found a lower success rate of 62 percent. (Power and Short, 1993)However, two systematic reviews failed to find sufficient evidence to supportthis treatment. (Naoumova, Kurol and Kjellberg, 2010;Parkin et al. 2012) In a Cochrane review, (Parkin, Furness and Shah,2012) only two studies from an original 324 met the inclusion criteria. Theauthors concluded that there are inconsistencies in the data.
They state theirconcerns about the design and report that neither trial provides evidence thatextraction of the primary canine as an interceptive technique is effective. The authors of theRoyal College of Surgeons guidelines suggest that further randomised controlledtrials are recommended to fully assess the effectiveness, although they dosuggest that consideration of this treatment seems reasonable in carefullyselected cases, provided patients/parents are warned that evidence is not conclusiveand further treatment may be required. (Husain, Burden and McSherry, 2016)Delaying treatment leads to longer, more costly options. Aroutinely used technique is surgically exposing the ectopic canine andattaching a gold change. The gold chain allows the tooth to be brought into thedental arch and is followed by alignment with the use of fixed orthodontics.
Two techniques are commonly used to expose the ectopic canine. The closedtechnique involves exposing the crown of the tooth, etching and bonding theenamel and attaching a gold chain. The flap is replaced and the gold chain thenhangs from the gingiva. This, after days of healing, has orthodontic tractionapplied to it to allow the tooth to gradually move into its correct positionbeneath the soft tissues. An alternative technique, the open technique, againinvolves exposing the displaced canine, however instead, a window is made inthe tissue covering the tooth, through which the canine is visible. The area isdressed and this dressing is removed after a few days.
The canine can then beallowed to erupt itself or a gold chain can be attached and orthodontictraction placed on the tooth. General anaesthetic is commonly used in the UKfor both techniques. The use of local anaesthetic on top of this is stillencouraged to reduce post-operative pain. (Mittal, Murray and Sandler, 2012)Surgical removal of an ectopic canine may sometimes be indicated if the patientdoes not want active treatment or are happy with the appearance of their teeth.
The best results are achieved if the patient is happy to have orthodontictreatment to reduce the space or if a good contact is present between thelateral incisor and pre-molar prior to treatment. Transplantation of the tooth is not commonly carried out. Ifthe patient is not happy to wear an orthodontic appliance or there is a largedegree of malposition, transplantation can be considered. Sufficient space mustbe available and enough alveolar bone must be present to accept thetransplanted canine. The transplanted tooth will often require root canaltreatment depending on the stage of root formation.If the patient does not want treatment and is happy withtheir appearance, the tooth can be left and observed.
In order to be left, noevidence of root resorption or cystic change must be present. If the tooth isto be left, it must be carefully clinically monitored on a regular basis toensure no pathological changes occur. (Husain,Burden and McSherry, 2016)A number of audits looking at the timing of referrals ofectopic canines have been published from around the United Kingdom. (Hyde,Barber and Spencer, 2015; Patel and Taylor, 2016) Given the impact of latereferrals on treatment, a referral appropriately timed can reduce the cost andimprove the effectiveness of treatment. It has been found that delays inreferral can remove the chance of straight-forward interceptive extractions andlead to more complicated, costly treatment. In 2016 an audit was published inBritish Dental Journal.
This found that 76 percent of patients were referredlate when compared to the Royal College of Surgeons guidelines. (Patel andTaylor, 2016) A re-audit published in 2015 in the British Orthodontic SocietyClinical Effectiveness Bulletin found that following some interventions such asdelivery of local lectures, alongside an electronic learning package for localdentists, the percentage of patients referred appropriately regarding anectopic canine increased 20 percent from 40 percent to 60 percent. (Hyde,Barber and Spencer, 2015) RationaleAround the United Kingdom, audits have been carried outdetermining whether or not ectopic canines are referred appropriately. However,no audits looking into the timing of ectopic canine referrals to the UniversityDental Hospital in Cardiff have been carried out. By carrying out this audit,it can be determined whether timing is appropriate when compared with the RoyalCollege of Surgeons guidelines. Asdiscussed previously, late referral reduced the chance of the option of earlyinterceptive treatment being appropriate, leading to costlier and lengthiertreatment.
If it is found that patients are being referred late, interventionsthat have previously been successful, such as lectures and electronic learningpackages can be put in place. (Hyde, Barber and Spencer, 2015) A re-audit couldthen be carried out at a later date to compare referral times to those found inthis audit and determine whether referral times have improved.Aims and ObjectivesThe main aim of the audit was to determine whether current referralsof patients with ectopic maxillary canines to the University Dental Hospital inCardiff are appropriately timed.
Genderof the referred patients, the position of the canine and associated pathologywere also investigated.MethodologyThe standard set for the audit was based on the Royal Collegeof Surgeons of England guidelines on Management of the Palatally EctopicMaxillary Canine. All patients with an ectopic maxillary canine should bereferred by the age of 12 years. Data was collected retrospectively. Data wascollected from patients who were on the joint-clinic waiting list June 2017 whowere referred regarding an ectopic maxillary canine.
Data was obtained over sixmonths from their medical records using a standardised collection proformawhich can be found in appendix A. Each set of medical records contained a standardreferral form filled in by the referrer. This included date of referral andsome information about why the patient is being referred. In some cases, areferral letter was included that explained the findings further.
The datacollected included patient age at referral, gender, source of referral,left/right or bilateral canine, and palatal or buccal position. Once collected,data was analysed using Microsoft Excel