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Cleidocranial dysplasia – the Jerusalem Approach: part 2

Published: October 2013

Bulletin #26 October 2013

Cleidocranial dysplasia – the Jerusalem Approach: part 2


Part 1 of this short series of articles on the treatment of Cleidocranial dysplasia can be found in the September 2013 bulletin #25 on this website. It was pointed out there that, for a good proportion of Cleidocranial dysplasia patients, the jaws are normally related to one another in the sagittal plane. Nevertheless, the prevalence of a skeletal class 3 discrepancy is unusually high in these patients and its early orthopedic treatment was discussed in part 1.

It was emphasized that treatment aimed at erupting the multiple impacted teeth should be delayed until the patient’s dental age reaches 7 years. This is the age in the normal child at which the permanent incisors erupt and it coincides with development of approximately ½ – ¾ the final length of the completed root.1-3 Since tooth development in CCD is usually about 3 years delayed 4-6 in relation to the unaffected child, this means that treatment for the resolution of the multiple impactions is not advised until the CCD patient reaches 10 years of age. Thus a window of opportunity presents to initiate maxillary protraction in the very young patient, aimed at treating the developing skeletal class 3 problem which, in CCD, is mainly due to maxillary hypoplasia.

In some, the attempt to treat the Class III dysgnathic relation may have failed due to poor cooperation of the patient with wearing the face mask. In these circumstances it is frequently more advantageous, in the long run, to foreclose on the protraction attempt. It is probably more beneficial to renew the momentum of treatment on another facet of CCD and to try to achieve some recognizable progress by redirecting to the eruption of teeth, in order to revamp the patient’s motivation for treatment, rather than to fight the uphill orthopedic battle with poor compliance and no improvement in sight. In others, the patient may arrive at a dentist’s doorstep to seek treatment for the first time only at around the age of 10 years, when erupting the individual teeth will need to take precedence over attempting skeletal orthopedic correction.

Q_Fig.1aQ_Fig.1b

Fig. 1. Intra-oral views of the dentition of a 13 year old CCD male patient, showing a complete deciduous dentition and only the erupted first molars of the permanent dentition. The clinical condition indicates a mild skeletal Class III inter-arch relation.

CCD patients attend their first consultation with a variety of over-retained deciduous teeth in the mouth. By and large, the first permanent molars erupt in all four quadrants4, 5 and, in addition, there may be one or more of the permanent incisors in a state of partial eruption, although an intact and complete deciduous dentition is not unusual (Fig. 1). With an older patient, there may be more erupted or partially erupted incisors and the posterior deciduous teeth are frequently affected by caries. A panoramic radiograph will reveal the presence of all the unerupted permanent teeth, while a careful examination will usually permit the identification of several supernumerary teeth, particularly in the maxillary midline area, but often elsewhere, too (Fig. 2). In some cases, the crowding that is produced by the multitude of unerupted teeth causes the tooth germs of many of them to be displaced deep into basal bone, including those of the normal series. Without intervention, the close proximity of the developing roots to the lower border of the mandible or to the floor of the nose may result in stunted or distorted root configurations.

In line with normal dental development in an unaffected child, it is desirable that the teeth in the CCD patient erupt into the mouth at the time when there is an open apex and one-half to three-quarters of the eventual expected root length. At the age of 10 years, the only teeth answering to these criteria are the incisors in both jaws. The premolar teeth are not expected to reach this level of development for a further 3 or 4 years. Thus any attempt to surgically expose and orthodontically erupt all incisors, canines and premolars in a single surgical episode, would be strongly contraindicated. On the other hand, to delay the treatment for 3 or 4 years, to the same end, would mean leaving the incisors and their associated supernumerary teeth to develop their roots in extremely cramped circumstances. With their root apices becoming fully closed, they would lose any of the already reduced eruptive potential that they may have initially possessed.

A more serious result of complete elimination of all the deciduous teeth and all the buried supernumerary teeth is the fact that the patient would be almost totally edentulous for a lengthy period of time, with only the permanent molars available to support an orthodontic appliance. This would severely tax the resources available to devise a biomechanical system needed to vertically erupt the permanent teeth - not to mention the debilitating, functional and social aspects of such a drastic line of treatment.

In the Jerusalem method of treatment4, 5, 7, surgery is performed in two distinct stages. The timing of these surgical episodes is directly related to the dental age at which the different groups of teeth reach the point in time at which they should be normally erupting, i.e. ½ – ¾ of their eventual root development. Thus, the first surgical episode is planned for dental age 7 years, which translates into the patient’s chronologic age of 10 years, in most cases and involves the incisor teeth of both jaws only.

In this way, the first permanent molars and the deciduous canines and molars remain in place to provide the patient with the means to function and also to provide the orthodontist with several available teeth to use as support and anchorage for the orthodontic appliances. Mechanically efficient application of vertically directed force may then be brought to bear on the unerupted incisors.

The second surgical episode will be planned when the canines and premolars realize the same root development requirement, i.e. 3-4 years later. By that time, the incisor teeth will have been fully erupted and aligned, to provide the patient with adequate function and appearance, but also to permit the inclusion of these teeth into the support and anchor unit of the orthodontic appliance for the efficient eruption and alignment of the posterior teeth.

This month’s bulletin deals with the incisor phase of tooth eruption, the orthodontic appliances needed for its effective execution, the requirements of the surgical procedure and the tasks that must be fulfilled before the patient is wheeled out of the operating theatre. It also proceeds to discuss ways in which to successfully erupt the teeth and then to align them in the dental arch and into a suitable archform.

Preparing the patient

Q_Fig.2a

Fig. 2a. poor quality cephalogram at 12 years of age shows a steep mandibular plane and vertical growth direction. The mass of superimposed, unerupted teeth can be clearly seen to be at considerable distances from the occlusal plane. The top part of the film has been deliberately “photoshopped” to illustrate the open anterior fontanelle and coronal suture.

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Fig. 2b The initial panoramic view

Q_Fig.2c

Fig. 2c. A tracing of the panoramic view in Fig. 2b with the deciduous teeth labeled A-E, the permanent teeth labeled 1-8 and the supernumerary teeth asterisked.

For the purposes of illustrating the method, we will describe a dentition exhibiting the “worst case scenario”, meaning that, aside from erupted first permanent molars, the only other erupted teeth are the deciduous teeth incisors, canines and molars – 20 in all (Fig. 1). An initial examination with the pediatric dentist needs to be arranged at which the permanent molars, deciduous molars and deciduous canines are examined for caries and treated restoratively in the normal way, while oral hygiene is reinforced and any other necessary preventive measures are instituted. It should be remembered that these deciduous teeth will need to be maintained in a healthy state for a further 3-4 years. The orthodontist will require a panoramic view and a cephalometric radiograph, but it is more than likely that these will be available from visits to other medical and dental practitioners (Fig. 2a, b). It should be borne in mind that the CCD patient will be required to have many radiographs and CBCT’s both for diagnosis and for follow-up of the treatment during the years ahead. Monitoring of the number and type of films that are needed should be carried out and care exercised in commissioning new films in order to reduce the considerable dosage of ionizing radiation to which the patient will inevitably be subjected.

The initial films need to be carefully studied to identify the teeth of the normal series and the supernumerary teeth. The individual teeth on the film should be traced, labeled accordingly and the case discussed with the surgeon in regard to the upcoming first surgical phase (Fig. 2c). A decision needs to be made regarding which teeth will be extracted, which surgically exposed and which exposed-and-attachment-bonded. A cone beam CT will often be an essential diagnostic aid at this stage and, for the most part should be considered mandatory.

Appliance construction

It is essential that the patient should go into the operating theatre set up with the adequate initial construction in place, from which to apply extrusive forces to the impacted teeth. This is best initiated during the actual surgical procedure itself and before the patient is aroused from the anesthetic. If this is attempted later, there is a very strong chance of failure due to the fact that the patient is fully conscious, soft tissues tend to close over any partially erupted teeth and there is considerable tenderness of the recently surgically traumatized oral soft tissues – even several weeks later.

Q_Fig.3aQ_Fig.3b_1

Q_Fig.3c Q_Fig.3d

Fig. 3. The basic appliance

a. Maxillary and mandibular appliances consist of palatal and lingual arches soldered to bands fitted on the first permanent molars. Round buccal tubes of internal diameter 0.036” (0.9mm) are soldered to the buccal sides of the bands. Removable, heavy (0.036”), self-supporting archwires are fashioned with a bayonet bend stop at the molar tubes.

b, c detail of the individual archwires, showing the bayonet bends on each side, a mesially and distally facing hook in each of the canine areas and an anterior soldered wire frame.

d. Eyelets prepared with soft 0.012” ligature wire tightly twisted but freely swinging, ready for bonding

Separating elastics are inserted interproximally in the molar areas and, a few days later, plain bands are adapted to the four molar teeth. An alginate or compound impression is made of each arch with the bands in place and the bands are then removed and relocated in the impression before the model is poured. On the cast models, a lower lingual and upper palatal arch of 0.036” heavy steel wire are constructed and soldered to the lingual side of the bands. Round 0.036” tubes are then soldered to the buccal side of the bands in each jaw. A heavy labial archwire is then fashioned in 0.036” round cross-section steel wire and slotted into the buccal tubes on each side. The wire is prevented from sliding too far into the tube by a U-loop on each side of the archwire, which is designed to hold the anterior portion of the heavy archwire 2 or 3 millimeters labial to the deciduous incisors. A distally-facing hook is soldered in the canine area on each side of the archwire and a small wire frame is soldered in the midline area. This represents the basic appliance (Fig. 3) and, when placed in the mouth, is entirely passive. The molar bands and lingual arches should be cemented into place a week or so before the proposed surgery, to be sure that all is well. The removable labial archwires are not inserted at this stage but will be taken to the operating theatre separately.

A good alternative to this system requires the placement of orthodontic brackets on the deciduous molars and canines at a uniform height, so that a plain archwire may be introduced immediately. No brackets are placed on the deciduous incisors.

Surgery and interdisciplinary cooperation

As noted above, many impacted teeth in CCD patients are to be found very deep into the basal bone. To follow an open exposure policy would entail removing the supernumerary teeth and all the bone around the impacted teeth of the normal series down to the CEJ. It also means maintaining the patency of the exposure by reducing the soft tissue and placing surgical packs, together with the need to suture the surgical flaps to prevent the gingival tissues from re-covering the exposed teeth. To do this for a series of deeply impacted teeth would mean paring the height of the alveolar bone down to the level of the necks of these teeth. This would result in a very radical removal of bone and a potentially dangerous weakening of the body of the mandible, in particular

Q_Fig.4a_cQ_Fig.4d_e_final

Fig. 4. Surgery was performed in both jaws together, in July 2006, by Prof. J. Lustmann and Dr. E Regev. Surgery in the mandible:

a. A full labial flap is reflected from the gingival margins of the deciduous teeth

b. The crowns of the four incisors are exposed. Because supernumerary teeth were extracted, the degree of crown exposure on one or two of the normal teeth was relatively large. In this case, the patient’s age was more advanced and the canines more developed, corresponding with 2-3 years beyond the ideal time. Accordingly, the canines were also exposed in this first surgical stage. Note the extreme height difference between the deciduous and the permanent anterior teeth.

c. Eyelet attachments were bonded by the orthodontist and oriented in line with the long axis of the teeth.

d. The removable labial arch is re-inserted and lies in its passive state.

e. With light finger pressure, the anterior portion of the heavy labial arch is gently flexed inferiorly and the twisted ligature wires engage it by bending them over the archwire, thereby holding it down under light force. An extrusive force is now being applied to the impacted anterior teeth. The soldered lingual arch can be clearly seen, superior to the activated labial arch.

A closed surgical exposure policy is strongly recommended for these teeth (Fig.4, 5). This means opening an attached gingiva flap from the gingival crevice of the deciduous teeth, following their extraction, identifying the crypts of the teeth deep in the sulcus and removing only the thin shell of bone on the buccal aspect of the teeth. The follicle is opened only on this aspect and only enough to provide enamel surface large enough to accept a small bonded attachment. Bone is not removed occlusally nor interproximally and bone channeling in the intended direction of tooth movement is avoided. Every effort is made to conserve as much bone as possible, in the interests of maintaining and, eventually, enhancing alveolar bone height.Q_Fig.5a_d

Q_Fig.5e__f

Fig. 5. Surgery in the maxilla:

a-f. Parallel stages as per the mandibular surgery.

g. The extracted deciduous and supernumerary teeth from the surgery.

h. The immediate post-surgery panoramic view

Long term experience has shown and it is emphasized that overlying bone is not an impediment to the movement of the impacted teeth. It resorbs in response to the vertical extrusive forces in the same way as forces acting on erupted teeth in routine orthodontic practice.8, 9

The orthodontist should be on hand to bond simple eyelets to the exposed and bonded incisor teeth, with the eyelets oriented parallel to the long axes of the teeth concerned (Fig.4c, 5c,d). The pigtail ligatures that are twisted into the eyelets are drawn vertically, while the removable archwires are reinserted into the horizontal buccal tubes (Fig. 4d, 5e). The pigtail ligatures are then bent over to ensnare the heavy labial archwire under some pressure, which deflects the archwire towards the impacted teeth (Fig. 4e, 5f). The archwire is now loaded with an extrusive force. The surgeon then closes and sutures back the full flap to cover the entire exposed surgical field.

Q_Fig.5gQ_Fig.5h

Fig. 5g. The extracted deciduous and supernumerary teeth.

Fig. 5h. The immediate post-surgery panoramic view

With the alternative method, in which brackets had been placed on the deciduous molars and canines, a fairly substantial (0.016” or 0.018” stainless steel) archwire is ligated into to all the brackets, with the twisted ligatures hooked over the free anterior portion.

Back in the Orthodontic Clinic

The patient will be seen by the surgeon in a post-surgical visit, prior to releasing him/her home. A further visit will generally be scheduled for follow-up of healing and removal of sutures a week or so later and then the patient will be referred back to the orthodontist for the continuation of the treatment.

The anchorage employed in the initial activation of the heavy archwire is from the molar teeth and from the lingual and palatal arches. If this is not reinforced with effective supplemental resistance, the molars will tip mesially and, in the maxilla in particular, the palatal arch will impinge on the palatal tissue and may sometimes become buried in it. The alternative method of placing orthodontic brackets on the deciduous molars and canines will reduce, but not eliminate, the likelihood of this complication.

On the first post-surgical visit to the orthodontist, usually 3-4 weeks later, the tissues will be tender and the patient very apprehensive. For these reasons, it is wise to limit the treatment provided at this appointment to cleaning the general surgical area with atomized water from the triple syringe. If one or more of the pigtail ligatures are causing ulceration of the lips or tongue, they should be carefully rolled up with a plier or ligature director. However, it is often wise to use surface anesthetic spray to limit the discomfort engendered by the manipulation.

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Fig. 6. The upper and lower anterior teeth seen here to be erupting, in February 2007. Note the use of a single anterior up-and-down elastic, placed on the distal-facing hooks on each side of both jaws and being held away from the tissues in the midline by the soldered wire frame. Intermaxillary vertical elastics represent the most important and most efficacious means of applying vertical extrusive force to the anterior teeth in both jaws.

The best way to guarantee the effectiveness of the anchor unit is to apply vertical “up-and-down” elastics to the labial arches, whether heavy archwires or the partially bracketed appliance system (Fig. 6). Aside from anchorage considerations, intermaxillary vertical elastics also have a very positive effect on the extrusive forces that have been applied to the teeth. For this reason, the first post-surgical visit is also the first real opportunity to teach the child to place up-and-down elastics. The distal-facing hooks on the heavy archwires were designed with this in mind. A single 3/8” or 5/16” medium elastic is stretched from the right to left hooks in the maxilla and then vertically down to engage the parallel hooks on the mandibular archwire. To keep the middle part of the elastic clear of the healing gingiva, it is stretched labially over the small soldered wire frame in the midline.

In the bracketed system, right and left small up-and-down elastics (3/16” heavy) must be placed on prepared hooks on the deciduous canine and first deciduous molar brackets.

Further activation should be made every 3-4 weeks, in line with the progress towards the eruption of the teeth. As the pigtail ligatures become longer and as the initial activation becomes exhausted, they require to be rolled up to maintain the momentum of the extrusive force. The teeth will come through fairly quickly, depending upon their initial degree of displacement and ectopy, the range and magnitude of the force and the frequency with which adjustments are made. They erupt in a markedly lingual position and with a lingual inclination, because the point of application of the extrusive force is to a labial attachment.

The vertically-oriented eyelets, that had been bonded to the teeth at the surgical procedure, become fully visible supra-gingivally when the incisor teeth are fairly well erupted. At this point the heavy archwire should be discarded and regular brackets placed on the deciduous molars and canines at a uniform height, as with the alternative bracketed system. The two systems are now identical.Q_Fig.7

Fig. 7. In November 2007 and once the eyelet attachments had become fully exposed supragingivally, standard Tip-Edge orthodontic brackets (TP Orthodontics) were placed and routine leveling and alignment commenced, using a two-by-four Johnson-type appliance. The new permanent teeth typically erupt with a strong lingual inclination and expanded coil springs were placed on the buccal arms to procline them and to achieve good archform. This also provides space for eruption of the canines (arrows). At the same time, vertical up-and-down elastics were re-instituted to close down the wide open bite.

A flexible superelastic nickel-titanium wire of 0.012” or 0.014” gauge should now be threaded through each of the eyelets of all four erupted incisors and tied into the remaining brackets in the normal way. This step requires just one visit for it to be immensely effective at leveling the teeth and eliminating even gross rotations where there is no room for the placement of a bracket in an ideal position. At the next visit, the eyelets should be debonded and regular orthodontic brackets substituted (Fig. 7). Simple labial tipping of the anterior teeth in both arches will correct their post-eruptive lingual inclination. It will have the effect of establishing, for the first time, a normal archform and a normal incisor height. Space in the posterior region will be increased to provide place for the eventual eruption of the permanent canines and premolars.

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Fig. 8. Panoramic view of August 2008 of August 2008 shows the premolar teeth with largely completed root apices and, therefore, late for the second orthodontic/surgical phase. Note also that the right mandibular second molar has fully erupted and that the other second molars appear to have a good prognosis for spontaneous eruption, which is frequent in CCD patients. Note also the development of a 4th maxillary molar on each side, apart from the 3 supernumerary teeth in the premolar areas.

The treatment time for this first stage of treatment ranges between 1.5 – 2.5 years, depending on the severity of the condition at the outset and the efficiency of the mechanotherapy. The patient may now be ready, in terms of the maturation of the premolar and canine teeth, to continue on to the second stage of treatment. However, for the most part, there will be a further 2 years or more before the treatment may be renewed.

In many cases, alignment, leveling and uprighting of the teeth will have been achieved while realizing the above goals. However, once these main goals have been attained, all treatment should stop and any uncompleted root movements, particularly bucco-lingual root torque, should be relegated to the second stage of treatment, when all necessary root movements will be tackled simultaneously for all the erupted teeth (Figs. 8, 9).

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Fig. 9. Completion of the first orthodontic/surgical phase of treatment, with good alignment and archform and adequate bite closing achieved. Note the worsening skeletal Class III relation.

If the oral hygiene has been good, the caries rate low and the estimated time span between stages will not be too long, the appliances may be left in place and remain as retainers. Otherwise, they should be removed and simple removable retainers placed until the second stage may begin.

References

1. Nolla CM. The development of permanent teeth. J Dent Child 1960; 27: 254–266.

2. Koyoumdjisky-Kaye E, Baras M, Grover NB. Stages in the emergence of the dentition: an improved classification and its application to Israeli children. Growth 1977; 41: 285–296.

3. Grøn A-M. Prediction of tooth emergence. J Dent Res 1962; 41: 573–585.

4. Becker A, Lustmann J, Shteyer A. Cleidocranial dysplasia: part 1 – general principles of the orthodontic and surgical treatment modality. Am J Orthod Dentofacial Orthop 1997; 111: 28–33.

5. Becker A, Shteyer A, Bimstein E, Lustmann J. Cleidocranial dysplasia: part 2 – a treatment protocol for the orthodontic and surgical modal- ity. Am J Orthod Dentofacial Orthop 1997; 111: 173–183.

6. Seow WK, Hertzberg J. Dental development and molar root length in children with cleidocranial dysplasia. Pediatr Dent 1995; 17: 101–105.

7. Becker A. The orthodontic treatment of impacted teeth. 3rd edition. Oxford: Wiley-Blackwell Publishers, 2012.

8. Becker A. Extreme tooth impaction and its resolution. Seminars in Orthodontics, 2010, 16:222-233.

9. Becker A, Chaushu S. Palatally impacted canines: The case for closed surgical exposure and immediate orthodontic traction. American Journal of Orthodontics and Dentofacial Orthopedics 2013;143:451-459.