Introduction
Class II malocclusion cases are of interest to orthodontists since they constitute a significant chunk of cases they treat. Still, they're one of the most gruelling malocclusions to diagnose and treat.
There lies a significant difference in the frequency of Class II malocclusion among various populations. Emmanuel1 observed 1.1% frequency in Nigerian, whereas Silva et al2 observed as high as 21.5% presence of Class II malocclusion in Latino adolescents. Frequency of Class II malocclusion in India varies from 1.9% in Rajasthan to 8.37% in South India.3, 4 Class II division 2 (Deckbiss) malocclusion is characterized by mandibular incisors positioned posterior to the cingulum of retroclined maxillary incisors. It usually presents with reduced overjet and increased overbite. Classically, the maxillary central incisors are retroclined and the maxillary lateral incisors are proclined.5
Combination of hyperactivity of the labial musculature and a superiorly positioned resting lip line is believed to be the genesis of maxillary incisor retroclination. The majority of the Class II division 2 malocclusions are present with a severe deep bite.6
Class II malocclusions have dental or skeletal or both components. Likewise, they can be attributed to maxillary prognathism, mandibular retrognathism or a combination of both along with problems in the transverse and vertical dimensions. The treatment approach of Class II division 2 malocclusion is different for different age groups. In growing cases, growth modulation with myofunctional appliances is recommended but in adult cases, orthodontic camouflage or orthognathic surgery is the recommended treatment modality.
Nevertheless, in grown-ups, aesthetics is the major concern in Class II division 2 cases. The treatment of severe dentofacial abnormalities in adult cases is a gruelling task for both the orthodontist and the maxillofacial surgeon. Treatment is arduous because of the facial discord, absence of jaw growth and a tendency to regress back to the original state of malocclusion. 7 Critical analysis and ortho-surgical combination treatment approach are to be reckoned on for gaining optimum aesthetic harmony and functional effectiveness. Likewise, acceptance of a pleasing facial appearance is the most eloquent factor in determining social relationships. 8
Case 1
The first case describes a 19 years old girl who reported to orthodontic OPD with the principal complaint of backwardly placed maxillary front teeth.
Clinical examination
The case had a roughly square face with a convex profile, inadequate lip competency and a deep mentolobial sulcus in pretreatment extraoral photographs (Figure 1). The patient had a Class II molar and canine relationship on both sides with retroclined incisors, a deep bite and a reduced overjet. Pretreatment intraoral photographs also showed that patient had a deep Curve of Spee, with moderate crowding in both the maxillary and mandibular arches (Figure 2). Lateral Cephalogram reveals that the case had a normal maxilla and retrognathic mandible giving a clear indication of skeletal Class II jaw bases (Figure 3).
Problem list
Flourosis w.r.t 11,12,21,22,31,32,41,42
Gingival recession w.r.t 31,41
Convex profile
Inadequate lip competency
Deep mentolabial sulcus
Rotation w.r.t 13,15,16,25,26
Crowding in maxillary and mandibular arch
Molar relation Class-II on both sides
Canine relation Class-II on both sides
Reduced overjet
Deep bite
Treatment objectives
The treatment’s main goals were to ameliorate facial aesthetics, achieve a pleasing facial profile, achieve lip competency, correct mandibular retrognathism, align maxillary & mandibular incisors, achieve normal bilateral Class I molar and canine relationship and correct overjet and overbite relationship.
Treatment Plan and Progress
Presurgical orthodontic phase
0.022" MBT PEA was used to band and bond the maxillary arch and thereafter 0.012" NiTi was ligated in the upper arch. Lower arch banding and bonding was done after the maxillary arch was levelled and aligned. The case's presurgical pictures (Figure 4, Figure 5) and radiographs (Figure 6) were re-recorded and the case was re-evaluated. A mock surgery was planned, prediction tracing was performed and a surgical wafer splint (Figure 7, Figure 8) was made. At the conclusion of the presurgical phase, 0.021" X0.025" SS wires with soldered interproximal spurs were inserted in the maxillary and mandibular arches.
Surgical phase
To rectify anterioposterior skeletal discrepancy, the orthognathic BSSO procedure (Figure 9) was performed with a 6 mm mandibular advancement. The lower jaw was stabilized with I-plates using the surgical wafer splint as a guide (Figure 10).
Postsurgical orthodontic phase
The stabilising archwires and wafer splint were removed four weeks after surgery. Occlusal settling was commenced in the maxillary and mandibular arches using 0.014" Australian super plus wires and short Class II elastics (3/16") were applied in quadrangular form (Figure 11). The fixed orthodontic appliance was removed after all of the treatment goals were met. For post-treatment retention, the case was given Hawley's retainers.
Treatment results
The facial and occlusal results were excellent. There was an appreciable improvement in the facial profile (Figure 12). Intraorally, a normal overjet and overbite relation was accomplished with a bilateral Class I molar and canine relationship (Figure 13). The deep mentolabial sulcus was corrected. Mandibular retrognathism was corrected from ANB 6 ˚ TO 3 ˚ (Table 1, Table 2) Before debonding, post-treatment radiographs (Figure 14) revealed an increase in lower anterior face height.(Figure 15) depicts cephalometric superimposition before and after treatment. Overall, the case was satisfied with the treatment results.
Case 2
The second case describes an 18 years old girl who reported to orthodontic OPD with the principal complaint of backwardly placed upper front teeth.
Clinical examination
The case had a roughly square face with a convex profile, competent lips and a deep mentolobial sulcus in pretreatment extraoral photographs (Figure 16). Patient had a Class II molar and end on canine relationship on both sides with retroclined incisors, a deep bite and a reduced overjet. Pretreatment intraoral photographs also showed that patient had a deep Curve of Spee, with mild crowding in both the maxillary and mandibular arches (Figure 17). Lateral Cephalogram reveals that the case had a normal maxilla and retrognathic mandible giving a clear indication of skeletal Class II jaw bases (Figure 18).
Problem list
Non consonant smile arc
Deep mentolabial sulcus
Reduced LAFH
Tongue-tie
Crowding (2.5 mm in upper arch, 3 mm in lower arch)
Retroclined upper and lower incisors
Rotation w.r.t 11, 12, 13, 21, 22, 31, 32, 41, 42
Impacted 18, 28, 38, 48
Deep bite
Reduced overjet
Molar relation Class-II on both sides
Canine relation end on bilaterally
Class II jaw bases with a horizontal growth pattern
Treatment objectives
The treatment’s main goals were the enhancement of profile, enhancement of her smile aesthetics, levelling and alignment of both the upper and lower arches, correction of deep bite, correction of molar and canine relation bilaterally, correction of LAFH & correction of Class II jaw bases.
Treatment Plan and Progress
Presurgical orthodontic phase
0.022" MBT PEA was used to band and bond the maxillary arch and thereafter 0.012" NiTi was ligated in the upper arch. Lower arch banding and bonding was done after the maxillary arch was levelled and aligned. The case's presurgical pictures (Figure 19, Figure 20) and radiographs (Figure 21) were re-recorded and the case was re-evaluated. A mock surgery was planned, prediction tracing was performed and a surgical wafer splint (Figure 22, Figure 23) was made. At the conclusion of the presurgical phase, 0.021" X0.025" SS wires with soldered interproximal spurs were inserted in the maxillary and mandibular arches
Surgical phase
To rectify anterioposterior skeletal discrepancy, the orthognathic BSSO procedure (Figure 24) was performed with a 7mm mandibular advancement. The lower jaw was stabilized with I-plates using the surgical wafer splint as a guide.
Postsurgical orthodontic phase
The stabilising archwires and wafer splint were removed five weeks after surgery. Occlusal settling was commenced in the maxillary and mandibular arches using 0.016" Australian super plus wires and short Class II elastics (3/16") were applied in triangular form (Figure 25). The fixed orthodontic appliance was removed after all of the treatment goals were met. For post-treatment retention, the case was given Begg’s wrap-around retainer in the maxillary arch and FSW retainer in the mandibular arch.
Treatment results
The facial and occlusal results were excellent. There was an appreciable improvement in the facial profile (Figure 26). Intraorally, a normal overjet and overbite relation was accomplished with a bilateral Class I molar and canine relationship (Figure 27). The deep mentolabial sulcus was corrected. Mandibular retrognathism was corrected from ANB 6 ˚ TO 2 ˚ (Table 3, Table 4). Post-treatment radiographs (Figure 28) revealed an increase in lower anterior facial height. (Figure 29) depicts cephalometric superimposition before and after treatment. The total treatment duration was 18 months. The treatment goals set in the pretreatment planning stage were achieved.
Table 1
Cephalometic reading (Patient-1)
Table 2
Linear measurement oncephalogram (Patient-1)
Table 3
Cephalometic Reading (Patient-2)
Table 4
Linear measurement on cephalogram (Patient-2)
Discussion
Depending on the patient's growth state and the severity of the situation, Class II malocclusion can be treated with different modalities. Fixed functional appliances can be used to correct orthodontic problems in adolescents.9 In grown-ups’ however, correction is achieved either through orthodontics alone (Camouflage) or an orthodontic-surgical combination. When orthodontic treatment alone is ineffective or when face aesthetics is grossly undermined, orthognathic surgery is recommended. There are numerous examples of adult cases with severe skeletal Class II Div 1 malocclusion with mandibular retrognathism that have been effectively corrected with BSSO. 10, 11
But, case reports of orthosurgical correction of severe Class II division 2 malocclusions are rare. In an adult patient with underlying dentoskeletal discrepancy, surgery is one of the treatment options if the dental defect cannot be corrected by orthodontics alone or if dental camouflage would involve technical or periodontal contraindications or would not produce a marked aesthetic improvement. It can therefore be reasonably said that the majority of adult Class-II patients require orthosurgical treatment, chiefly in order to provide an optimal solution to their aesthetic problems.12
In the present case series, two adult cases of severe Class II division 2 (Deckbiss) malocclusion were treated with orthodontic-orthognathic combination. The treatment was directed to relieve crowding, correct underlying skeletal antero-posterior disproportion and ameliorate facial aesthetics. Post-treatment results of both the cases showed marked improvement in facial aesthetics and dental occlusion. Convex facial profile and deep mentolobial sulcus were corrected and lower anterior facial height was increased.
Conclusion
Treatment of severe Class II division 2 malocclusion in adult cases is a gruelling task. Treatment can be done by camouflage or orthosurgical approach. But if the problem is too severe for orthodontic correction alone and when the underlying skeletal problem impairs facial appearance a combined orthosurgical approach should be used. BSSO surgery has proven to be of great success time and again when executed meticulously in such types of cases.
