Early treatment of Class III incisor relationship using the chincap appliance.
Optimal treatment of a Class III malocclusion with skeletal disharmony requires . as a unit from molar to canine, resulting in a Class I dental relationship. . own personal expectations, combined with the orthodontist's professional advice and . Eur J Orthod. Oct;15(5) Early treatment of Class III incisor relationship using the chincap appliance. Allen RA(1), Connolly IH, Richardson A . Class III malocclusion is a less frequently observed clinical problem than Class II or . of the molars, sagittal skeletal support by the Hybrid Hyrax is very useful. a class III molar and premolar relation and class I canine relation with normal.
To achieve good alignment and leveling, a fixed appliance must be used [ 25 ]. Using a facial mask was not considered because of the age of the patient and the fact that the harmonic basal bone relationship was within normal limits.
Treatment Progress The patient was first submitted to a rapid maxillary expansion, once finished this first phase we bonded a preadjusted Edgewise 0. After correcting the anterior crossbite, the use of the bite plane was suspended, and maxillary sequential bonding was performed visualizing a corrective orthodontic treatment in the second phase.
The treatment of the mandibular arch began two months after inserting the maxillary 0. Both arches finished with a 0. At the end of the treatment the pseudo-Class III relationship was compensated during the second phase.
The space gained with the maxillary expansion and maxillary incisors protrusion helped in the eruption of the maxillary canines and the correction of the anterior crossbite.
In the mandibular arch, the position of the transalveolar right second premolar self-corrected and erupted after extraction of the mandibular deciduous right second molar, avoiding the need for the surgical exposure planned at the beginning of treatment.
Facially the treatment did not change her growth pattern, and the Class III characteristics were maintained Figure 4. Posttreatment photographs and radiographs. Discussion Treatment of a pseudo-Class III malocclusion must be performed as soon as it is detected and should be considered as a Class III malocclusion [ 4 ]; however, the clinician is unfortunately not always able to evaluate the patient during the developmental stage of this type of malocclusion. Anterior crossbite has been associated with a variety of complications, such as gingival recession of the lower incisors, incisal wear, and worsening of the growth pattern; correcting an anterior crossbite consequently increases the maxillary arch perimeter, offering more space for the canines and premolars to erupt and therefore a more stable orthopedic result [ 4 — 8 ].
The functional appliances used to treat Class III malocclusion work by permitting the eruption of the maxillary molars and maintaining the mandibular ones in position, leading to an occlusal plane rotation that helps shift the molar relationship from Class III to Class I [ 9 ].
When treating young patients with anterior crossbite in mixed dentition, better results can be achieved through the association of maxillary expansion due to orthopedic stability and the movement of the maxilla down and forward [ 10 ]. The association of maxillary expansion with fixed appliances improves the arch perimeter, reducing the number of extractions in patients with slight to mild crowding. Superimposition of pre- and post-treatment cephalometric tracings. The vertical dimension also increased.
The upper molars were mesialized and extruded, and the upper incisors moderately protruded. The lower molars were intruded; each posterior segment was distalized as a unit from molar to canine, resulting in a Class I dental relationship.
In addition, the lower incisors were retruded as the overjet and overbite were corrected. Facially, the soft-tissue profile and smile line improved due to retrusion of the lower lip, better balance of the lower facial third, and protrusion of the upper lip to a more harmonious position. Retrusion of menton occurred as a consequence of the reposturing of the mandible and opening of the maxillomandibular angle.
Records taken 19 months after completion of active treatment confirmed the stability of the results Fig. Patient 19 months after completion of active treatment. Case 2 A year-old female presented with the desire to correct her reverse overjet and the esthetics of her smile Fig.
Her chief complaint was the functional incongruence between her dental arches, especially when chewing. The patient displayed a full-step Class III relationship of the molars and canines, anterior and posterior crossbites on the right side, a 2. Her skeletal anomalies included a divergent facial type and a skeletal Class III with bilateral maxillary constriction. The prominence of the patient's lower lip in relation to the upper lip increased the prognathic aspect of her face in profile.
Although she was conscious of her facial appearance, she was not concerned about the mandibular prognathism, which was an accepted trait in her family.
She did, however, want to diminish the concavity of her midface. Functionally, she exhibited macroglossia, with the tongue interposed between the dental arches at rest; perioral hypertonicity, with a thin, slightly short upper lip; and an obtuse nasolabial angle. Her periodontal condition was healthy, but she showed severe gingival recession and a thin periodontium due to vigorous, improper tooth-brushing.
The brackets were copolymer prototypes selected by the patient. Ten weeks later, an upper.
After four months of treatment, upper. After five months of anteroposterior correction, a Class I platform was achieved in the posterior segment, completing stage one Fig. Class I platform achieved after five months of Motion treatment. Brackets and molar tubes were then bonded in the mandibular arch, and a round.
Six weeks later, a lower.
incisor relationship - oi
After 10 months of treatment, an upper. After 10 months of treatment, upper. After 12 and a half months of treatment, an upper. After a total 18 months of treatment, the fixed appliances were removed, and a upper lingual retainer was bonded Fig. For a final esthetic touch, minor labial recontouring was performed in the upper arch by injecting a hyaluronic acid dermal filler at the lip border. Cephalometric superimpositions indicated a slight distal reposturing of the mandible at the level of the temporomandibular space, as shown by a slight reduction in ANB Fig.
The upper molars were extruded and also migrated mesially, resulting in a Class I dental occlusion. The upper incisors were protruded, and the open bite was closed. The final profile reflected a retrusion of the lower lip and protrusion of the upper lip. As in Case 1, the occlusal plane suffered a counterclockwise rotation. Clinical experience with the device has demonstrated skeletal and dental changes, alterations of the occlusal plane and the intermaxillary relationship, and improvement of soft-tissue prognathic conditions.
Skeletally, the appliance fosters a functional repositioning of the condyle in the temporomandibular complex. After mounting the upper and lower casts remove the construction bite and fabricate an inverted labial bow [Figure - 2] and Adams clasp with 0. Further, stabilize the inverted labial bow by using wax and construct the acrylic plate as the Hawleys appliance [Figure - 2].
Diagnosis and Treatment of Pseudo-Class III Malocclusion
Modified Hawleys appliance was constructed with inverted labial bow. The appliance was delivered with instruction to use it at night for a week and return for follow-up [Figure - 3]. After a week, the patient was comfortable and functional shift of mandible occurred in the edge-to-edge incisor relation while closing [Figure - 4]. The patient then was asked to use the appliance continuously, except while eating and report after three weeks.
With regard to continuous use of appliance for one month, the patient was able to comfortably close the mandible in centric occlusion with positive overbite. Also, there was almost intercuspation in posterior occlusion, with normal lip relation and profile [Figure - 5]. The appliance was discontinued after two months when normal occlusion was achieved in centric occlusal relation without the appliance and the patient was advised to use the appliance only at night as a retainer for six months.
Other alternative therapies that may correct skeletal problems in young patients have been shown to be effective, with significant changes in the craniofacial complex, including the use of protraction headgear, chincap, and Frankel III.
The therapeutic use of a modified Hawleys appliance with inverted labial bow is suggested in this case report with anterior crossbite in mixed dentition as the simplest way of managing anterior crossbite as compared to other conventional appliances mentioned in the literature.