A two stage non extraction treatment of distoocclusion with proclination of upper incisors (AII/1)

Extra-oral examination: mesocephalic, round symmetric face, pupils equally round, pupillary line horizontal, competent lips with average tonicity.

Examination of TMJ: Maximum mouth opening - 50mm, no displacement or deviation on closure, without pain and pathological sounds and path of closure.

Intra-oral examination: Average oral hygiene, low cariosity, pink gingiva, oral mucous membrane with no pathological signs, good periodontal condition, upper labial frenulum inserts to the incisive papilla.

Cast analysis: Permanent dentition, AII/1, overjet=9.5mm, overbite=6mm, crowding in the lower dental arch, deep bite, accentuated curve of Spee, spaces and anomalies of position of individual teeth present, space discrepancy in maxilla +2mm, in mandible -1mm, anterior Bolton ratio - 71,3%, overall Bolton ratio - 87,5%, Tonn‘s index - 68%, McNamara analysis - 38mm.

Cephalometric analysis before therapy: SNA: 80°, SNB: 77°, SNPo: 78°, ANB: 3°, Wits: 2mm, NS-ML: 32°, S-Go:N-Me: 66%, Mx 1-NS: 114°, Mx 1-NPo: 9.5mm, Interincisal: 123°, Mn 1-ML: 90°, Mn 1-Apo: -1,5mm, Beta: 17°.

Analysis of cervicovertebral maturation on the cephalometric X-ray: the end of the second stage, growth spurt commences

AII/1; Overjet: 9.5mm; Overbite: 6mm; Class I skeletal base; Average growth pattern; Deep bite; Accentuated curve of Spee; Gaps between teeth 12-11-21; Distally rotated teeth 13, 25, 35, 45; Mesially inclined tooth 43; upper labial frenulum inserts to the incisive papilla.

Treatment objectives:
1st phase: Reduction of overjet and overbite using functional appliance, to achieve class I molar and canine relationship.
2nd phase: To level upper and lower dental arch, to close the gaps, to derotate and align individual teeth, to set correct overjet and overbite.

Treatment plan and appliances:
Myofunctional appliance – Bionator
Preadjusted edgewise appliance – slot .022, prescription Roth, low-profile metal brackets
Orthodontic bands 16, 26, 36, 46
Orthodontic brackets 15-25, 35-45
Plan of occlusion - AI

Maxilla:
1. Levelling and aligning (NiTi .014)
2. .017x.025 NiTi
3. .017x:025 SS
4. Interarch elastics of II.class 6.4H
5. Retention - ESSIX and fixed retainer 11-21

Mandible:
1. Levelling and aligning (NiTi .014)
2. .018 NiTi
3. .017x.025 NiTi
4. .017x.025 SS
5. Interarch elastics of II.class 6.4H
6. Retention - ESSIX

Cephalometric analysis after the therapy: SNA: 85°, SNB: 82°, SNPo: 83.5°, ANB:1.5°, Wits: 0.6mm, NS-ML: 28°, S-Go:N-Me: 68%, Mx 1–NS: 106°, Mx 1–NPo: 6mm, Interincisal: 130°, Mn1-ML: 96%, Mn1-Apo: 1.8mm, Beta: 20°.

Ideal timing for treatment of mandibular deficiency is during pubertal growth spurt. The success of treatment with functional appliances depends on the patient cooperation and favourable mandibular growth. With 24 hour wear of appliance it is possible to reposition mandible forward and to raise a deep bite in about 6-9 months according to severity of malocclusion. With the successful first stage of the treatment, the second stage of treatment with fixed appliance is significantly reduced in time. Therefore there is a lower risk of white spots and gingivitis occurring during the treatment.