Kocadereli I Early treatment of posterior and anterior crossbite in a child with bilaterally constricted maxilla: report of case. J Dent Child. 1998; 65:41-46
Jirgensone I, Liepa A, Abeltins A Anterior crossbite correction in primary and mixed dentition with removable inclined plane (Bruckl appliance). Stomatologija, Baltic Dent Maxillofac J. 2008; 10:140-144
Jacobs SG Teeth in crossbite: the role of removable appliances. Aust Dent J. 1989; 34:20-28
Anterior crossbite or reverse overjet is the term used to describe an abnormal labiolingual relationship between one or more maxillary and mandibular incisor teeth. This may involve just a single tooth or up to all the upper incisors. Interceptive treatment is usually carried out in order to reduce the severity of this developing malocclusion in the mixed dentition. Different techniques have been used to correct anterior crossbite with variable effectiveness. This case report demonstrates a simple and cost-effective method for the correction of severe segmental anterior crossbite with a removable, lower Catalan's appliance initially and upper posterior biteplane with a z-spring later.
Clinical Relevance: Anterior crossbite correction in the early mixed dentition is highly recommended as this kind of malocclusion does not diminish with age and could lead to further complications. Removable appliances are safe, cost-effective, rapid and an easy alternative for the treatment of crossbite cases requiring simple tipping, in contrast to a fixed appliance, which can be use in more complex conditions, is expensive, unaesthetic, difficult to maintain and needs a posterior bite platform incorporated.
Article
Gaurav Khurana
One of the chief objectives of any orthodontic treatment is to guide the developing dentition to a state of normality in line with the stage of oral-facial growth and development. The period of mixed dentition offers the greatest opportunity for occlusal guidance and interception of malocclusion1 which, if delayed to a later stage of maturity, may mean that treatment becomes more complicated.2 Anterior dental crossbite is one such type of malocclusion which requires early and immediate treatment to prevent abnormal enamel abrasion, anterior teeth mobility and fracture, periodontal pathosis and the possibility of temporomandibular joint disturbance.3,4,5 The main goal of treatment is to tip the affected maxillary tooth or teeth labially to the point where a stable overbite relationship exists.5 Relapse is usually prevented by achieving the normal overjet/overbite relationship.
A variety of factors6,7,8 have been reported to cause anterior dental crossbite:
Trauma to the primary incisor resulting in the lingual displacement of the permanent tooth germ that may cause eruption of permanent teeth rotated or in a crossbite relationship;
Supernumerary anterior teeth;
An over-retained necrotic or pulpless deciduous tooth or root that may cause deflection of permanent teeth in the area;
Various methods have been proposed for correction of anterior dental crossbite with variable effectiveness. In cases of a single tooth crossbite, appliances like tongue blades9,10 reverse stainless steel crowns,11 or removable acrylic appliances with z-springs12 are usually effective, whereas segmental crossbites can be efficiently treated with removable/fixed acrylic inclined biteplanes13 or a fixed multi-bracket appliance system. Fixed appliance treatment is an easy and efficient treatment modality for the treatment of segmental crossbite. However, placing a fixed multi-bracket appliance in the mixed dentition stage together with a removable posterior biteplane (to provide the necessary anterior clearance) and then later replacing it with a retainer for maintenance of the bite is cumbersome. A fixed acrylic anterior inclined biteplane is a simple and cost-effective alternative to a multi-bracket technique; it has some disadvantages also. Apart from the problems of speech, mastication and aesthetics, the main limitation is that it needs to be removed frequently to check whether the correction has been achieved and then recemented if the crossbite still persists, which is somewhat traumatic. If the patient is co-operative, a removable inclined plane can be used to overcome these limitations.
This case report demonstrates sequential correction of a severe anterior segmental crossbite by conventional removable appliance therapy using a removable lower anterior inclined biteplane in the initial phase and an upper posterior biteplane with z-springs in the later stage to bring about necessary final correction.
Case report
Clinical examination and diagnosis
A nine-year-old male patient presented complaining that his lower teeth were in front of his upper teeth. No relevant medical problems were elicited. Intra-oral examination revealed a mixed dentition phase with primary molars in mesio-occlusion. All permanent first molars and incisors, except for the upper right lateral incisor, had erupted, whereas permanent canines and premolars were in differing stages of eruption. The upper incisors, along with the deciduous canines, were in a crossbite relation with the lower anteriors, with a negative overjet of 2 mm and a deep overbite (Figure 1). Cephalometric examination revealed a mild mandibular prognathism, retroclined upper and lower anteriors and a slight concave profile. The panoramic radiograph showed a vertically impacted upper right lateral incisor (Figure 2).
Figure 1.
(a–e) Pre-treatment intra-oral photographs.Figure 2.
(a, b) Pre-treatment panoramic radiograph and lateral cephalogram.
Treatment objectives
To correct anterior segmental crossbite;
To establish a positive overjet and unlock the maxilla and to allow it to grow;
To procline the upper anteriors and create space for the right lateral incisor.
Treatment planning
Considering that the skeletal base discrepancy was mild and there was good soft tissue compensation, the need for any separate phase of growth modulation was not warranted and it was decided to treat the case using dento-alveolar camouflage (Catalan's appliance). As the patient was highly motivated and co-operative, a removable Catalan's appliance, extending from canine-to-canine, was placed (Figure 3). The patient was advised to wear the appliance on a full-time basis and to remove it only whilst eating. In the meantime, the thick fibrous gingiva hindering the eruption of the upper right lateral incisor was reflected, following which the tooth erupted normally. After six weeks of appliance wear, the central incisors came to an edge-to-edge bite and the right lateral had erupted half of its crown length (Figure 4). In order to achieve a positive overjet, further proclination of the central incisors was desired, but using the Catalan's appliance for the same purpose beyond a period of six weeks is not indicated as it can cause the posterior teeth to supra-erupt. Hence a posterior biteplane along with a double cantilever spring was used to procline the central incisors and thereby gain space for the alignment of lateral incisors (Figure 5). After four months, the central incisors proclined adequately and an overjet of 2 mm was attained (Figure 6). The final step was to correct the crossbite in relation to the upper lateral incisors and create space for the alignment of the upper right lateral incisor. For this purpose, an appliance consisting of a posterior biteplane with double cantilever springs on the lateral incisors and a helical canine retractor on the upper right deciduous canine was used (Figure 7). Within a period of 5 months, the lateral incisors were well aligned in the arch with a positive overjet of 2 mm and an overbite of 2 mm (Figure 8).
Figure 3.
(a–c) Removable Catalan's appliance in place.Figure 4.
(a–c) After Catalan's appliance removal.Figure 5.
(a–c) Posterior biteplane with z-spring for labial movement of upper central incisors.Figure 6.
(a–c) After labial movement of upper centrals.Figure 7.
(a, b) Posterior biteplane with z-spring for labial movement of upper lateral incisors.Figure 8.
(a–c) Complete correction of crossbite and establishment of positive overjet.
Discussion
Anterior crossbite correction in the early mixed dentition is highly recommended as this kind of malocclusion does not diminish with age and could lead to further complications. Correcting a single/segmental crossbite using a tongue blade,10 or a reverse stainless steel crown,14,15 or inclined plane16 has been frequently reported but using sequential removable appliances in the treatment of anterior segmental crossbite has been rarely documented. This case report demonstrates the successful early intervention of a severe anterior segmental crossbite by means of removable appliances used in a sequential manner, as the individual corrections were achieved.
Selection of the appliance is critical as it forms the basis for the long-term success of crossbite correction. In the present case, a removable appliance was preferred over a fixed appliance as the inclination of the upper incisors was such that the crowns were palatally inclined whilst the roots were slightly labial. In such conditions, removable appliances are amenable in generating tipping forces which tip the crown of the palatally inclined upper incisors in a labial direction. In other cases, where the incisor roots are also palatally displaced, a removable appliance will not produce full correction and a fixed multi-bracket appliance would be necessary to produce efficient torquing of incisor roots, along with the crossbite correction.
Though the use of a 2 x 4 fixed appliance comfortably serves its purpose, with no treatment demands on the part of the patient or the parents, its use in the correction of crossbite is limited to more complex conditions as it is expensive, unaesthetic, difficult to maintain and needs a posterior bite platform incorporated. On the other hand, removable appliances are safe, cost-effective, rapid and an easy alternative for the treatment of crossbite cases requiring simple tipping.17
With increasing demand for orthodontics, the use and practice of removable orthodontic appliances in the early interception of such malocclusions by a general dental practitioner, with adequate training in diagnosis and treatment planning, is quite beneficial as it allows the specialist to concentrate on more difficult cases.
The use of removable appliances still varies widely between clinicians, but it is possible to achieve adequate occlusal improvement with these appliances, providing that suitable cases are chosen.9 It is vital to emphasize that cases suitable for removable appliance treatment are those that require simple tipping movements only, and surprisingly few malocclusions will fall into this category. Poor diagnosis can often lead to maltreatment of the malocclusion and the patient being worse off than before treatment.
Removable appliances should not be seen as an appliance for those patients whose oral health or motivation does not reach the standards required by fixed appliances. In addition, removable appliances should not be seen as an alternative method of treating complex malocclusions when the clinician has not acquired the necessary skills in fixed appliance therapy. However, although removable appliances can be used by the general dentist, they still need to be used with considerable skill and careful monitoring to produce good results.7
One of the shortcomings of early crossbite correction is the possibility of a two-phase orthodontic therapy as it is often difficult to estimate the further growth of the mandible.5 A major factor in determining the success of early crossbite correction is whether or not a positive overbite could be achieved. In this case report, a positive overbite was established and therefore the prognosis for maintaining the corrected bite was good. Although the use of these appliances produces good results, success relies totally upon the patient wearing them.
Conclusion
The abovementioned case report describes that removable appliances are an acceptable alternative for correction of anterior dental crossbite rather than complicated fixed orthodontic therapy, with no damage to teeth or marginal periodontal tissue. Each case must be assessed on its merits and due consideration must be given to the diagnosis and evaluation of the malocclusion and facial profile.
