NEWSLETTERS

A Gross Miscarriage of Justice!

Published: June 2017

Bulletin #67 June 2017

A Gross Miscarriage of Justice!

A number of years ago, an American-trained orthodontic colleague was sued by the parents of a patient for damage caused to their son, who had lost a lateral incisor and an impacted canine as the result of treatment. They asserted that these two anterior teeth had to be extracted “as the result of the orthodontist’s negligent orthodontic treatment”. They accused the orthodontist of gross incompetence and were seeking serious financial compensation. The case was being heard in the Court of Justice in a European capital city. The orthodontist contacted me and asked me to study the patient’s records and to give written evidence to the Court in his defence.

The child was seen initially in 1992, when he was in the mixed dentition period. At the time, the orthodontist commissioned complete records, which included full mouth periapical radiographs and a standardized lateral head film (cephalometric view), together with extra-oral and intra-oral clinical photographic material. He studied the case, declared that the child was too young for orthodontic treatment and that a phase I procedure was not appropriate. He advised that the child be re-examined by him periodically until the dentition was ripe for a full (phase II) treatment plan in the permanent dentition. For his discussion with the parents, he had made indelible markings directly on the film to show the axial orientations of the two unerupted maxillary canines, indicating that he was concerned that these teeth could become impacted. Although potentially helpful in his explanations to the parents, this defacing of radiographic material is strongly discouraged.

He subsequently saw the child again in February 1996, in the permanent dentition stage, with all adult teeth erupted except the right maxillary canine, the maxillary second and all third molars. At this time, an over-exposed panoramic view indicated that the right maxillary canine had become impacted in close association with the root apex of the lateral incisor. Because of the over-exposure, the film did not permit a definitive picture and, although root resorption was not observed, its presence could not be ruled out. This case was seen and treated in the pre-cone beam CT years. Both the surgeon and the orthodontist relied almost completely on 2-dimensional periapical and panoramic views for the 3-dimensional diagnosis of location of the canine.

By November 1996, fixed appliance therapy had created space in the dental arch for the unerupted right canine and the patient was referred to the oral surgeon for its surgical exposure and the bonding of an attachment. No information as to the exact location of the canine was given by the orthodontist to the surgeon, because a new film was not performed and neither did the surgeon request this information.

According to the surgeon, as reported in the court records, he did not perform any new pre-surgical radiographs and neither did he take a confirmatory post-surgical view for presentation to the orthodontist, to aid in traction and alignment of the canine. He reported that the surgery, which had been performed from the palatal side, had been very difficult and that access to the canine had been difficult to establish. However, he had managed to bond a button attachment to underside of the tooth.

The orthodontist took a follow-up progress film (another panoramic view) and periapical views only 6 months post-surgery and was surprised at what he saw. The button attachment could clearly be seen bonded to the underside of the canine, but there was also a severe shortening of the root of the lateral incisor. He showed this to the patient and referred him back to the surgeon.

The surgeon immediately informed the parents, quite categorically, that the shortening of the lateral incisor root had been due to resorption which had been generated by excessive forces from the orthodontic appliances, thus pointing an accusing finger at the orthodontist!

The surgeon then took a series of completely irrational steps.

1. He extracted the unerupted canine – presumably because this tooth had been the cause of the problem – the “aggressor” tooth.

2. He then performed root canal therapy on the lateral incisor – the unfortunate “victim” tooth. He used calcium hydroxide paste, in an unfounded and futile attempt to stop the progress of the supposed resorption – presumably because he had been taught that root resorption is treated in this way. He seems to have been unaware that this is only true when the resorption has been the sequel to an incident of trauma.

3. The periapical radiographs of the lateral incisor that he took subsequently showed severe bone loss in the immediate area and a radiolucent periapical area around the truncated incisor root. He therefore extracted the lateral incisor under the misconception that the root resorption would be progressive.

4. All this time, he claimed that the orthodontist was responsible for the entire complex series of events.

As the result of these highly dubious treatment decisions, yet armed with the surgeon’s “expert” opinion regarding his culpability, the parents sued the orthodontist.

My Analysis

The radiographic records from 1992 and 1996 were sent to me together with subsequent films taken by the orthodontist in which he first saw the shortened incisor root. These included periapical surveys, panoramic views and lateral skull films (cephalograms). Additionally and only when subjected to a Court Order, the surgeon finally produced a set of 3 occlusal radiographs. These had all apparently been taken on the same day, or within a short period of time of one another, before and after the extraction of the canine.

67_Fig._1

Fig. 1a-e. The maxillary anterior teeth seen on the 1992 full-mouth periapical survey, from which both permanent canines may be diagnosed as labial to the roots of the incisors.

If we study 5 films of the anterior teeth from the full-mouth periapical survey taken in 1992 (Fig. 1a-e), which was 4 years prior to the ill-fated treatment, there is much to be learned regarding the location of both unerupted maxillary canines. The canines can be seen to superimpose on the apices of the roots of the lateral incisors. With two periapical films that depict the same area at different angulations on each side, one may legitimately employ these to perform a tube-shift determination of the bucco-palatal relationship between the canines and the incisors. The 2 films taken from a more distal vantage point (Figs. 1a & 1e) show the canine to overlap the apices of the incisors more than can be seen on the adjacent more mesially-angulated films (Figs. 1b & 1d). This clearly indicates that the canines are labial to the incisor roots. This can be easily confirmed by studying the lateral skull radiograph (Fig. 2), in which the 2 canines are readily visible superimposed on each other and indisputably anterior to the roots of the incisors.

67_Fig._2

Fig. 2. The June 1992 lateral head film showing the labial location of the two superimposed maxillary canines (arrows).

We have reported that a panoramic film may also be used for confirming the location of palatal canines, based on the relative enlargement of the projected shadow of the canine on to the film, which occurs due to its greater distance from the film than all the other teeth. However, this method is only valid when any superimposition of the canine on the incisor roots is in the apical third of the lateral incisors.1, 2 This is not the case here, since the overlap is high on the apices of the lateral incisors (Fig. 3).

67_Fig._3

Fig. 3. The June 1992 panoramic radiograph showing the canines in close relation with the apical area of the lateral incisors on each side.

The 1992 panoramic view shows no evidence of root resorption of the right lateral incisor. Unfortunately, the 1996 film (Fig. 4) which was taken immediately prior to the commencement of orthodontic treatment, is of poor diagnostic quality, with an inability to distinguish the integrity of the roots of the teeth. Root resorption of the lateral incisor in question cannot be ruled out, although if it were present, then the contention that the cause was orthodontic treatment must be denied, since treatment had not started.

67_Fig._4

Fig. 4. The February 1996 panoramic radiographs illustrates the complete and spontaneous resolution of the left canine. By contrast, the right canine has hardly altered its location and its relation to the lateral incisor apex in the 3.8 years. The poor quality of the film makes a diagnosis of incisor root resorption impossible.

Turning our attention now to the post-surgical panoramic view of April 1997, we can easily identify the shortened incisor root. The canine can be seen superior to it, with a button bonded to its inferior surface.

67_Fig._5

Fig. 5. The April 1997 panoramic film taken 6 months post-surgery shows the truncated lateral incisor and a bonded button on the inferior aspect of the labial canine.

The orthodontist called the surgeon and requested details of the surgical exposure and was informed that the approach to the tooth had been very difficult. This was a surprising comment, since access to a labial canine at this height should have been extremely simple.

The surgeon then reported that he had opened a palatal flap and had approached the canine from the palatal side. He noted that, from that direction, the tooth had been hard to find because it was located high up and much bone had to be removed to gain access. The radiolucent area around the distal of the lateral incisor and inferior to the canine, seen on the film, bears witness to this.

My understanding of this scenario is that the palatal approach to a canine that was labial to the root of a lateral incisor was impossible without meeting the intervening incisor root. The fact of the reported difficulty in reaching the canine and the amount of bone removed would indicate that bone was not the only material removed, but that the dentine of the root of the incisor had also been removed. This was clearly compounded by the need to create a space inferior to the canine and distal to the incisor to accommodate the bonded button, together with satisfying the physical criteria necessary for bonding in a confined area.

67_Fig._6a 67_Fig._6b

Fig. 6a, b. Taken in July 1988, the panoramic view and the two periapical films show the severe loss of bone support following the extraction of the canine and in spite of subsequent partial bony repair.

At 21 months following the exposure, the panoramic and periapical views of July 1998 (Fig. 6a, b)show further loss of bone and lamina dura following the extraction of the canine. On the basis of these films, the lateral incisor was then extracted.

67_Fig.7

Fig. 7a, b. Two anterior oblique occlusal radiographs taken at different angles to establish a tube shift pair, which confirm the labial location of the maxillary canine.

Then we have the 3-film series of occlusal views, produced by the surgeon only after a court order was issued. Only the first two are shown here. These were taken at different angulations to the vertical, in order to establish a diagnostic pair of films in which the canine’s relation to the incisor roots could be seen, effectively setting up a vertical tube shift scenario. This is not the most enlightening of methods, because it does not show the relative height of the impacted tooth. However, it does confirm the labial position of the canine.

When a patient is referred to the surgeon for the exposure of an impacted canine, the surgeon will first determine its accurate location using whatever imaging is necessary. Since this patient was treated before spiral CT or CBCT were considered to be “the standard of care” for the more complex cases, the surgeon will have used one or more of the several methods of locating the tooth in the three planes of space before embarking on surgery. At the end of the procedure he will also have taken a single confirmatory repeat radiograph. These would normally be sent on to the referring orthodontist together with his surgical report and represents important information needed for the continuation of the treatment - not to mention that it would be accepted ethical behaviour expected from a colleague.

In the circumstances of this case, neither pre-surgical nor post-surgical films were sent to the orthodontist and the surgeon claimed that these had been “lost”.

To advise the judge in his deliberations in relation to this obviously highly technical and clinical subject, two expert witnesses were appointed by the Court, representing perhaps the specialties within dentistry furthest from the field. One was a specialist endodontist and the other a public health dentist, neither of whom had any knowledge or experience in the areas related to orthodontics and the treatment of impacted teeth. These honourable gentlemen, in their wisdom, recommended in favour of the surgeon and indicating the orthodontist’s liability for the damage caused to the patient! The judge accepted their advice and proceeded to commit a gross miscarriage of justice!

It is unfortunate that the presence and active involvement of the orthodontist in the surgeon’s operatory is not considered to be the standard of practice in these cases, since the treatment of the present case could have turned out very differently and no report would ever have been written. Given the crucial nature of the surgical episode to the success of the venture, it behoves the orthodontist to reconsider the practice of “sending” the patient to the surgeon, in favour of “taking” him there.3, 4

References

1. Chaushu S, Chaushu G, Becker A. The use of panoramic radiographs to localize maxillary palatal canines. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endododontics 1999; 88:511-516.

2. Chaushu S, Chaushu G, Becker A. Reliability of a method for the localization of displaced maxillary canines using a single panoramic radiograph. Clinical Orthodontics and Research 1999; 2:194-199

3. Becker A, Chaushu S. A chapter entitled: Surgical treatment of impacted canines: what the orthodontist would like the surgeon to know. Editor Michael Kleiman, in: Oral and Maxillofacial Surgery Clinics of North America. New York: Elsevier Inc. 2015;27:449-458.

4. Becker, A. Surgical exposure of impacted teeth. Chapter 3 in: Becker A. The orthodontic treatment of impacted teeth. 3rd edition, 2012. Oxford: Wiley-Blackwell Publishers. 2012. ISBN-13:978-1-4443-3675-7, ISBN-10:1-4443-3675-4