Journal of Orthodontics, Vol. 40, 2013, 326–344

CLINICAL SECTION

BOS MOrth Cases Prize 2011 Jigar Vipinchandra Patel Birmingham Dental Hospital, Birmingham, West Midlands, UK

This paper describes the orthodontic treatment of two cases awarded the prize by the British Orthodontic Society for best treated cases submitted for the Membership in Orthodontics. The first case reports on the treatment of a class III malocclusion with increased vertical lower anterior facial proportions and dentoalveolar compensation that was treated with orthodontic camouflage. The second case reports on the treatment of a class II division II malocclusion with reduced vertical lower anterior facial proportions and an overbite complete to the palate, which was treated with orthodontic camouflage. Key words: Camouflage, class III, class II division II, high angle, low angle Received 9 February 2013; accepted 9 May 2013

Introduction The British Orthodontic Society (BOS) medal is an annual national award for the best Membership in Orthodontics (MOrth) examination cases. Candidates from any of the Royal Colleges in the United Kingdom are invited to enter for this award. The cases were displayed at the British Orthodontic Conference in Harrogate in 2011.

Case report 1 A 16 year and 4 month old female presented with a class III incisor relationship on a skeletal III base with increased vertical lower anterior facial proportions. The malocclusion was complicated by an edge-to-edge overjet, reduced overbite and a centreline discrepancy. There was moderate crowding in the lower arch and severe crowding in the upper arch. Her main complaint was the appearance of her crooked teeth. She was medically fit and well and had no habits or any history of trauma.

Extra-oral assessment The patient presented with a class III skeletal relationship and increased lower face height proportion and an increased Frankfort-mandibular planes angle. She had acceptable facial symmetry in the transverse plane. She had competent lips at rest, which lay behind Ricketts’ E-plane.1 She presented with an average naso-labial angle and a flat labio-mental fold. On smiling she produced an average smile line (Figure 1a–d).

Intra-oral assessment The patient presented with acceptable oral hygiene and healthy periodontal tissues. All teeth in the permanent Address for correspondence: Jigar Vipinchandra Patel, Birmingham Dental Hospital, Birmingham, West Midlands, UK. Email: [email protected] # 2013 British Orthodontic Society

dentition were present except for the third molars. The dentition was caries free and there was a class II restoration on the LR7 (Figure 2a–e). The lower arch was U-shaped and had a moderate (6 mm) amount of anterior crowding. The lower incisors clinically appeared to be retroclined. The upper arch was U-shaped and had a severe (12 mm) level of crowding with the UR3 buccally excluded from the arch. Clinically the upper incisors appeared to be proclined. In occlusion, the patient presented with a class III incisal relationship with a 3 mm overjet to the UL1 and a 1 mm overjet to the UL1. The overbite to the UL1 was 0 mm and there was a 3 mm anterior open bite to the UR1. The centrelines were non-coincident, the upper dental centreline was 3 mm to the right of the mid-facial axis and the lower centreline was coincident to the chin-point and the mid-facial axis. The buccal segment relationship was class I bilaterally. There was a unilateral crossbite affecting the UR6, UR5, UR4 and UR2. There was no displacement associated with this crossbite. Analysis of the patient’s study models showed that she had an anterior Bolton ratio of 83.72 and an overall Bolton ratio of 92.47, which confirmed there was no tooth size discrepancy.2 The pre-treatment IOTN dhc was 4d,3 the IOTN ac was 8 and the PAR score was 52.4

Radiographic assessment A dental pantomogram radiograph (Figure 3) confirmed the presence of all permanent teeth including unerupted third molars. The bone levels and root length of the permanent teeth were within normal limits. The

DOI 10.1179/1465313313Y.0000000065

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Aetiology The class III sagittal and increased vertical skeletal discrepancies are likely to have resulted from a genetic basis. The mandibular morphology would suggest a ‘backward growth rotation,7,8 which is reflected in the reduced vertical overlap of the incisors. The crowding present is likely to be the result of dento-alveolar disproportion.

Aims and objectives of treatment 1. 2. 3. 4. 5. 6. 7.

Maintain a good level of oral hygiene throughout treatment Accept the skeletal base relationship Relieve crowding Level and align the arches and correct the upper centreline Correct the overjet and overbite Obtain class I incisors, canines and molars with good buccal interdigitation Retain

Treatment plan and rationale

Figure 1 (a–d) Case report 1: pre-treatment extra-oral photographs

radiograph suggested possible caries affecting the LR7 and the LL7. The patient’s general dental practitioner followed up this radiograph with further bitewings and a restoration on the LR7. The bitewing radiographs did not appear to suggest caries affecting the LL7. The lateral cephaologram taken supported the clinical appearance (Figure 4). The cephalometric analysis (Table 1) showed that the patient had SNA (80u) and SNB (81u) values within 1 standard deviation of Caucasian mean values.5,6 The ANB (21u) and the Wits appraisal (25 mm) reflected the class III skeletal relationship anteroposteriorly. The increased MMPA (36u) and lower anterior face height ratio (61%) reflected the increased vertical facial proportions. Dentally, the upper incisors were at an average inclination of 110u and the lower incisors were marginally retroclined (by 4u) at 80u for the increased MMPA. The lower incisors were 2 mm ahead of the A-Pogonion line and therefore within the average range for an aesthetic position for the lower incisors relative to the maxillary skeletal base. The lower lip was 4 mm behind Ricketts E-plane,1 suggesting that the lips were retrusive relative to the nose and chin.

The patient attended a multi-disciplinary clinic consisting of Oral and Maxillofacial Surgeons and Orthodontists. At the clinic, the option of orthognathic surgery with presurgical orthodontics was discussed. The surgical plan of choice was a Le Fort I maxillary advancement osteotomy with differential posterior impaction and a mandibular bilateral sagittal split setback osteotomy. At the clinic the advantages and disadvantages of a combined orthodontic treatment approach and an orthodontic camouflage treatment approach were discussed. The patient was adamant that she did not want to undergo orthognathic surgery, as she was perfectly happy with her facial profile and features. The patient only wished to seek treatment in order to improve the alignment of her teeth.

Plan 1. Extraction of the UR5, UL5, LR4 and LL4. 2. Upper and lower pre-adjusted edgewise appliances with a 0.02260.028-inch slot and MBT prescription. 3. Retention with upper and lower vacuum formed retainers.

Treatment progress Start. Bands were placed on all four first molars and the patient’s GDP was requested to extract the UR5, UL5, LR4 and LL4.

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Figure 2

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(a–e) Case report 1: pre-treatment intra-oral photographs

This was followed by the bonding of upper and lower pre-adjusted edgewise appliances (0.02260.028-inch slot, MBT prescription). All the teeth were bonded except for the UR3 and the second molars. The lower

canine brackets were transposed to reverse the tip on these teeth (Figure 5a–c). Upper: a 0.014-inch NiTi archwire was placed and active tiebacks placed to retract the UR4 and UL4.

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Figure 3 Case report 1: pre-treatment dental panoramic tomogram

Lower: a 0.014-inch NiTi archwire was placed and lacebacks tied LRQ & LLQ.

Month 2. Upper: a 0.014-inch Australian special plus archwire was placed and push coil placed between the UR2 and UR4 to create space for the UR3 and correct the upper centreline. Lower: the 0.014-inch NiTi archwire was re-tied. Month 4. A Begg bracket was bonded to the UR3. Upper: a 0.014-inch NiTi archwire tied to all the teeth from the UR6 to the UL6. Lower: a 0.014-inch Australian special plus archwire was placed with circle loops distal to the lower lateral incisors. Active tiebacks were placed from the first molars to the circle loops to retract the lower incisors.

Table 1

Figure 4 Case report 1: pre-treatment lateral cephalogram

Month 6. An MBT prescription pre-adjusted edgewise bracket was bonded to the UR3 to replace the Begg bracket (Figure 6a–c). Upper: a 0.014-inch NiTi archwire was tied to all the teeth from the UR6 to the UL6. Lower: a 0.014-inch Australian special plus archwire with circle loops distal to the lower lateral incisors was kept in place. Intra-arch elastics were worn (139 g) from

Case report 1: pre-treatment cephalometric analysis.5,6

Variable

Pre-treatment

Normal

SNA SNB ANB SN to maxillary plane Wits appraisal Upper incisor to maxillary plane angle Lower incisor to mandibular plane angle Inter-incisal angle Lower incisor edge to upper incisor root centroid Maxillary mandibular planes angle Upper anterior face height Lower anterior face height Face height ratio Lower incisor to APo line Lower lip to Ricketts E-plane

80u 81u 21u 3u 25 mm 110u 80u 137u z4 mm 36u 44 mm 69 mm 61% z2 mm 24 mm

81¡3u 78¡3u 3¡2u 8¡3u 1¡1.9 mm 109¡6u 93¡6u 135¡10u 0–2 mm 27¡5u 55¡3 mm 70.5¡4.5 mm 55¡2% 1¡2 mm 22¡2 mm

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Figure 5

(a–c) Case report 1: mid-treatment photographs

Figure 6

(a–c) Case report 1: mid-treatment photographs

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the first molars to the circle loops to correct the incisor relationship. The upper arch was then aligned with progressive NiTi archwires until the placement of an upper 0.01960.025inch steel archwire could be achieved. The lower archwires were progressed in steel wires until the placement of a 0.01660.022-inch steel archwire could be achieved.

side. Inter-arch (139 g) class III elastics were used on the left side to correct the buccal relationship (Figure 7a–c). Upper: a 0.01960.025-inch steel archwire was placed. Plain ligature was placed in the URQ and an active tieback was placed in the ULQ to close space. Lower: a 0.01660.022-inch steel archwire was placed and active tiebacks placed in the LRQ and LLQ.

Month 12. A metal button was bonded to palatal surface of UR4 and cross-elastics (104 g) were used from buccal hook on the LR6 to palatal button on the UR4 to correct the unilateral crossbite on the right hand

Month 14. Vertical inter-arch elastics were used on right hand side to maintain a class I canine relationship and class II inter-arch elastics were used on the left hand side to correct the molar relationship (Figure 8a–c).

Figure 7

(a–c) Case report 1: mid-treatment photographs

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Figure 8 (a–c) Case report 1: mid-treatment photographs

Month 17. Molar tubes were bonded to second molars. In the upper arch a 0.014-inch NiTi archwire was passed from the UR7 to the UL7 and concomitantly a 0.01960.025-inch steel archwire was passed from the UR6 to the UL6. The steel base archwire was bent to pass through the accessory tubes on the first molars. In the lower arch a 0.014-inch NiTi archwire was also passed from the LR7 to the LL7 and the 0.01660.022-inch steel passed from the LR6 to the LL6. The steel base archwire was bent to pass through the accessory tubes on the first molars. The use of the steel base archwires allowed for the continued use of inter-arch elastics whilst simultaneously allowing for the alignment of the second molars (Figure 9a–c)9. Near end of treatment radiographs were also taken at this stage (Figure 10a, b). Month 18. The UL3 and UL4 brackets were repositioned to the LA point and an upper 0.01660.022-inch NiTi archwire was placed to align these teeth. The upper archwires were progressed until a 0.01960.025-inch NiTi archwire could be placed and light vertical interarch elastics were continued. Month 22. The patient was debonded 22 months from the start of active treatment aged 18 years and 2 months.

Figure 9 (a–c) Case report 1: mid-treatment photographs

Upper and lower vacuum formed retainers were provided for night time wear.

Case discussion The patient’s presenting complaint of having crooked teeth was addressed and she had a significant improvement in her dental appearance. She finished with a class I incisal relationship, with coincident centrelines, an average overjet, an average overbite and a class I buccal segment relationship bilaterally with good interdigitation (Figure 12a–e). Her facial appearance remained relatively unchanged as she did not wish to undergo any surgical treatment option (Figure 11a–d). The patient was very happy with the treatment outcome and gained self-confidence as a result. Analysis of the treatment changes (Figure 10b and Table 2) showed that there had been some unfavourable forward growth of the mandible, which resulted in an increased skeletal class III relationship (Figure 13). There had not been any further increase in vertical facial growth, which was helpful for the overbite correction. The incisal relationship was corrected by a combination of upper incisor proclination and lower incisor retroclination (Figures 14 and 15). The upper incisors were proclined 4u more than average and the lower incisors

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Figure 11 (a–d) Case report 1: post-treatment extra-oral photographs Figure 10 (a, b) Case report 1: near end of treatment (a) DPT and (b) LSK

retroclined 9u more than would be expected with the MMPA (the expected lower incisor inclination would be 85u for the MMPA of 35u). The overbite correction was achieved by a combination of some extrusion of the upper and lower incisors and retroclination of the lower incisors. Despite relative mesial movement of the lower molars due to forward mandibular growth, the class I molar relationship was maintained by mesial movement of the upper molars. The lower inter-canine width was increased by 1 mm during treatment; however, the lower canines were lingually inclined at the start of treatment and they were also retracted distally to occupy a wider position in the lower arch. There was some root resorption seen on the near-end of treatment DPT affecting the UL2. This was not more than 2 mm and there was no significant root resorption seen on any other tooth. The relative position of the lips remained unchanged behind Ricketts’ E-plane, so treatment did not result in a more retrusive lip position. The prognosis of this case remaining stable is good. Correction of the overjet should be stable due to the

achievement of a positive overbite. As the overbite correction was achieved to some extent by upper and lower incisor extrusion there remains the potential for some relapse of the overbite. The patient was advised on the need for prolonged retention and vacuum-formed retainers were provided. The patient is unlikely to undergo significant further facial growth as she is now over 18 years of age. The achievement of good buccal intercuspation will help to aid occlusal stability. The post treatment PAR score was 1, indicating a 98% reduction.

Case report 2 Summary A 15 year and 3 month old female, presented with a class II division 2 incisor relationship with a 5 mm overjet and an increased overbite to the palate. She had a skeletal II dental base relationship with vertically reduced lower anterior facial proportions. Her malocclusion was complicated by increased incisal and

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Figure 12 (a–e) Case report 1: post-treatment intra-oral photographs

gingival show on smiling, mild lower arch spacing, mild upper arch crowding, a class II buccal segment relationship bilaterally and a previously traumatized LL1 which had been endodontically treated. Medically she was fit and well.

Extra-oral assessment The patient presented with a class II skeletal relationship with a reduced lower anterior face height proportion and a reduced Frankfort-mandibular planes angle. She

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Figure 14 Case report 1: maxillary superimposition on the anterior cranial vault

Figure 13 Case report 1: overall cephalometric superimposition on Sella-Nasion line at Sella

had acceptable facial symmetry in the transverse plane. She had competent lips at rest, which lay behind Ricketts’ E-plane.1 She presented with an average naso-labial angle and a deep labio-mental fold. On smiling she had increased incisal and gingival show due to the overeruption of her upper central incisors (Figure 16a–d).

Intra-oral assessment The patient presented with acceptable oral hygiene and healthy periodontal tissues. All teeth in the permanent Table 2

dentition were present except for the third molars. The dentition was caries free; however, the LL1 crown height was reduced due to a complicated crown fracture as a result of previous trauma. The LL1 had been endodontically treated by the patient’s general dental practitioner two years prior to the start of orthodontic treatment and the tooth had been asymptomatic since being treated (Figure 17a–e). The rest of the incisors all produced positive responses on vitality testing. The lower arch was U-shaped and had mild spacing (3 mm). There was an increased curve of Spee present and clinically the lower incisors appeared to be at an average inclination. The LL1 crown height was reduced due to missing coronal tissue but the gingival margin of this tooth was level with that of the other lower incisors. The upper arch was U-shaped and had mild crowding (4 mm) clinically the upper central incisors appeared to be retroclined.

Case report 1: near end of treatment cephalometric analysis.5,6

Variable

Pre-treatment

Post-treatment

Total change

SNA SNB ANB SN to maxillary plane Wits appraisal Upper incisor to maxillary plane angle Lower incisor to mandibular plane angle Inter-incisal angle Lower incisor edge to upper incisor root centroid Maxillary mandibular planes angle Upper anterior face height Lower anterior face height Face height ratio Lower incisor to APo line Lower lip to Ricketts’ E-plane

80u 81u 21u 3u 25 mm 110u 80u 137u z4 mm 36u 44 mm 69 mm 61% z2 mm 24 mm

80u 82u 22u 3u 25 mm 112u 76u 141u z4 mm 35u 44 mm 69 mm 61% 0 mm 24 mm

0u z1u 21u 0u 0 mm z2u 24u z4u 0 mm 21u 0 mm 0 mm 0% 22 mm 0 mm

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Figure 15 Case report 1: mandibular superimposition on the inner cortex of the lingual and inferior border of the mandibular symphysis and the cortical outline of the mandibular canal7

In occlusion, the patient presented with a class II division II incisal relationship with a 5 mm overjet. The overbite was increased and complete to the palate. The upper and lower centrelines were coincident with each other and with the mid-facial axis and chin point. The buccal segment relationship was class II bilaterally. Analysis of the patient’s study models showed that she had an anterior Bolton ratio of 76.74 which suggested no tooth size discrepancy between the upper and lower anterior teeth.2 The overall Bolton ratio was 88.51 which suggests there may possibly be a tooth size discrepancy, with the upper teeth comparatively larger than the lower teeth. Possible options to resolve this discrepancy if it were to affect the fit of the teeth were, to consider finishing with under-torqued upper anterior teeth or leaving the lower labial segment proclined. Alternatively, inter-proximal reduction of the upper teeth would assist if needed. The pre-treatment IOTN dhc was 4d,3 the IOTN ac was 6 and the PAR score was 40.4

Radiographic assessment A dental pantomogram radiograph (Figure 18) confirmed the presence of all permanent teeth including unerupted third molars. The bone levels and root length of the permanent teeth were within normal limits. The radiograph also showed the endodontically treated LL1. A long-cone periapical radiograph was taken of the LL1 (Figure 19) to assess the root condition and root filling on the tooth. The radiograph showed a good root filling present on the LL1 with no periapical pathology or root shortening present. The lateral cephalogram taken supported the clinical appearance (Figure 20). The cephalometric analysis

Figure 16 (a–d) Case report 2: pre-treatment extra-oral photographs

(Table 3) showed that the patient had an average SNA measurement (82u) and a reduced SNB (75u) measurement compared to Caucasian mean values,5,6 suggesting the patient had some mandibular retrognathia. The ANB (7u) and the Wits appraisal (9 mm) reflected the class II skeletal relationship anteroposteriorly. The lower anterior face height height to upper face height ratio was average (55%); however, the MMPA (19u) was reduced and clinically the patient appeared to have a vertically reduced lower anterior face height. Dentally, the upper incisors were retroclined (80u) and the lower incisors were slightly retroclined (95u) for the reduced MMPA (19u). The lower incisors were 4 mm behind the A-pogonion line and therefore in a retrusive position for aesthetics. The lower lip was 3 mm behind Ricketts’ E-plane,1 suggesting that the lips were retrusive relative to the nose and chin.

Aetiology The class II sagittal relationship and reduced MMPA are likely to have resulted from a genetic basis. The

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Figure 17 (a–e) Case report 2: pre-treatment intra-oral photographs

mandibular morphology would suggest a ‘forward growth rotation’ pattern of mandibular growth,7,8 which is reflected in the increased overbite seen. The increased overbite is also the result of over-eruption of the upper

and lower incisors due to the absence of occlusal contact on these teeth. Additionally the increased resting force of a higher lower lip line is probably contributing to the retroclination of the upper incisors.10

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Figure 18 Case report 2: pre-treatment dental panoramic tomogram

Aims and objectives of treatment 1. 2. 3. 4. 5. 6. 7. 8.

Maintain a good level of oral hygiene throughout treatment Accept skeletal base relationship Reduce tooth and gingival show on smiling Correct overjet and overbite Relieve upper arch crowding and close lower arch spacing Level and align the arches Obtain class I incisors and canines and a good buccal interdigitation Retain

Treatment plan and rationale The patient had a class II skeletal relationship with the cephalometric analysis confirming mandibular retrognathia. However, the patient also presented with a prominent chin position and it was felt that this could be adversely affected if a surgical treatment plan to

Figure 20 Case report 2: pre-treatment lateral cephalogram

advance the mandible was implemented. The patient had increased incisal tooth show on smiling due to overeruption of the upper incisors and it was felt that the most appropriate method to address the patient’s malocclusion would be to intrude the upper incisors to reduce the amount of tooth and gingival show on smiling. The malocclusion would then be camouflaged by retracting the upper incisors to reduce the overjet and torquing the upper incisor roots palatally,11 to reduce the inter-incisal angle and produce a positive upper incisor root centroid to lower incisor edge relationship, thus improve overbite stability following correction of the incisal relationship.12

Plan 1.

2. 3. 4. Figure 19 Case report 2: pre-treatment LCPA of LL1

Pre-adjusted edgewise appliance brackets with a 0.02260.028-inch slot and MBT prescription bonded onto the upper central incisors and an upper removable appliance with a flat anterior bite plane and gingival arms anteriorly made to intrude the upper central incisors with elastics. Extraction of the UR4 and UL4. Upper and lower pre-adjusted edgewise appliances with a 0.02260.028-inch slot and MBT prescription. Retention with upper and lower vacuum formed retainers.

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Figure 21 (a–d) Case report 2: mid-treatment photographs

Treatment progress Start. An upper removable appliance with a flat anterior bite plane, Adams cribs on the upper 6 3/3 6 and buccal arms extending upwards and forwards from the canine cribs was fitted. Pre-adjusted edgewise appliance (0.02260.028-inch slot, MBT prescription) brackets were bonded to the upper central incisors. The patient was instructed to wear elastics (43 g) from the Table 3

buccal arms and extend the elastic under the brackets on the incisors to intrude these teeth (Figure 21a–d).

Month 3. A lower pre-adjusted edgewise appliance (0.02260.028-inch slot, MBT prescription) was bonded to the lower teeth from the LR6 to the LL6. Upper: the patient continued with the URA. Lower: a 0.014-inch NiTi archwire was placed.

Case report 2: pre-treatment cephalometric analysis.5,6

Variable

Pre-treatment

Normal

SNA SNB ANB (corrected) SN to maxillary plane Wits appraisal Upper incisor to maxillary plane angle Lower incisor to mandibular plane angle Inter-incisal angle Lower incisor edge to upper incisor root centroid Maxillary mandibular planes angle Upper anterior face height Lower anterior face height Face height ratio Lower incisor to APo line Lower lip to Ricketts’ E-plane

82u 75u 7u (6.5u) 5u 9 mm 80u 95u 165u 25 mm 19u 48 mm 58 mm 55% 24 mm 23 mm

81¡3u 78¡3u 3¡2u 8¡3u 1¡1.9 mm 109¡6u 93¡6u 135¡10u 0–2 mm 27¡5u 55¡3 mm 70.5¡4.5 mm 55¡2% 1¡2 mm 22¡2 mm

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radiograph was taken to assess for root resorption during treatment (Figure 22).

Month 9. Upper: a 0.01960.025-inch steel archwire with increased palatal root torque in the upper anterior segment was placed and Figure 8 modules tied on the upper incisors. Lower: a 0.01960.025-inch steel wire was placed and cement was placed on the lower second molars to free the occlusion. Class II inter-arch elastics (139 g) were used to reduce the overjet and overbite simultaneously (Figure 23a–c). Figure 22 Case report 2: mid-treatment LCPA of LL1

Month 5. The patient’s GDP was requested to extract the UR4 and UL4. A pre-adjusted edgewise appliance (0.02260.028-inch slot, MBT prescription) was bonded in the upper arch from the UR6 to the UL6. Upper: a 0.012-inch NiTi archwire was placed and lacebacks tied bilaterally. Then the upper aligning archwires were worked up until a 0.01960.025-inch steel archwire could be placed. Lower: aligning wires were worked up until a 0.01960.025-inch steel archwire could be placed. The LL1 was built up with composite and an LCPA

Figure 23 (a–c) Case report 2: mid-treatment photographs

Figure 24 (a–c) Case report 2: mid-treatment photographs

Month 11. The same mechanics were kept to reduce the overjet and overbite simultaneously but 12 mm NiTi coil springs were placed in the ULQ and ULQ to reduce the overjet. (Figure 24a–c). Month 19. Molar tubes were bonded to second molars. In the upper arch a 0.014-inch NiTi archwire was passed from the UR7 to the UL7 and concomitantly a 0.01960.025-inch steel archwire was passed from the UR5 to the UL5. The steel base archwire was cut distal to the UR5 and UL5. In the lower arch a 0.014-inch NiTi archwire was also passed from the LR7 to the LL7 and a 0.01960.025-inch steel archwire was passed from

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Figure 25 (a–c) Case report 2: mid-treatment photographs

the LR5 to the LL5. The steel base archwire was cut distal to the LR5 and the LL5. The use of the steel base archwires allowed for the continued use of short class II inter-arch elastics (139 g), whilst simultaneously allowing for the alignment of the second molars (Figure 25a– c). Near end of treatment radiographs were also taken at this stage (Figure 26a, b).

Figure 26 (a, b) Case report 2: near end of treatment (a) DPT and (b) LSK

Month 20. Finishing steps, involving bracket repositioning and second order bends on light steel archwires were carried out to detail the occlusion. Month 24. The patient was debonded 24 months from the start of active treatment aged 17 years and 3 months. Upper and lower vacuum formed retainers were provided for night time wear.

Figure 27 (a–d) Case report 2: post-treatment extra-oral photographs

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Figure 28 (a–e) Case report 2: post-treatment intra-oral photographs

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Figure 30 Case report 2: maxillary superimposition on the anterior cranial vault

Figure 29 Case report 2: overall cephalometric superimposition on Sella-Nasion line at Sella

Case discussion The patient’s presenting complaint of having ‘crooked teeth’ was addressed and she had a significant improvement in her soft tissue profile (Figure 27a–d). The soft tissue improvement was focused on the deep labiomental fold she initially presented with. The camouflage treatment resulted in a reduction in redundancy of the lower lip and so lessened the deep labio-mental fold. The patient’s chin point has remained in an aesthetic position and close within the zero-meridian plane.13 The result supported the decision not to undertake any surgical intervention to advance the mandible but rather to treat this patient by camouflage treatment. Dentally, she finished with a class I incisal relationship with coincident centrelines, an average overjet, an average overbite and a class I buccal segment relationship bilaterally with good interdigitation (Figure 28a–e). The patient was very happy with the treatment outcome and gained greater self-confidence as a result. Analysis of the treatment changes (Figure 26b and Table 4) showed that there had been some favourable forward growth of the mandible (Figure 29) which was helpful in the correction of the overjet and skeletal discrepancy. The SNA reduced by 1u and this is likely to be due to the change in position of point A as the upper incisors have moved palatally causing remodelling of the dentoalveolar bone. However, there had not been any increase in vertical facial growth or the MMPA to aid overbite correction. The overbite and overjet correction

was achieved by intrusion and increased palatal root torque of the upper incisors (Figure 30) and by proclination of the lower incisors (Figure 31). The increased palatal root torque achieved on the upper incisors and proclination achieved on the lower incisors reduced the interincisal angle to 135u and produced a positive lower incisor edge to upper incisor root centroid relationship (Table 4) to aid stability of the overbite correction.12 The upper incisors finished within the average causation angulation at 105u and the lower incisors finished at 102u which is almost the expected angulation for the patient’s MMPA (the expected lower incisor angulation for the patient would be 101u). The lower incisors also finished on the A-Pogonion line which shows that they moved to a more aesthetic position. Analysis of the soft tissues shows a relatively unchanged naso-labial angle and a less accentuated labio-mental fold which has improved the profile aesthetics. The class II division II incisal relationship was corrected by the use of class II intermaxillary

Figure 31 Case report 2: mandibular superimposition on the inner cortex of the lingual and inferior border of the mandibular symphysis and the cortical outline of the mandibular canal7

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Table 4

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Case report 2: near end of treatment cephalometric analysis.5,6

Variable

Pre-treatment

Post-treatment

Change

SNA SNB ANB (corrected) SN to maxillary plane Wits appraisal Upper incisor to maxillary plane angle Lower incisor to mandibular plane angle Inter-incisal angle Lower incisor edge to upper incisor root centroid Maxillary mandibular planes angle Upper anterior face height Lower anterior face height Face height ratio Lower incisor to APo line Lower lip to Ricketts’ E-plane

82u 75u 7u (6.5u) 5u 9 mm 80u 95u 165u 25 mm 19u 48 mm 58 mm 55% 24 mm 23 mm

81u 77u 4u (4u) 5u 6 mm 105u 102u 135u z2 mm 19u 48 mm 60 mm 56% 0 mm 24 mm

21u z2u 23u (22.5u) 0u 23 mm z25u z7u 230u z7 mm 0u 0 mm z2 mm z1% z4 mm 21 mm

elastics alone. Anchorage reinforcement in the upper arch with the use of temporary anchorage devices or extra-oral traction may have aided the correction of the incisal relationship and limited the degree of lower incisal proclination by reducing the need for intermaxillary elastic traction. The prognosis of this case remaining stable is good. Correction of the overjet should be stable due to the competency of lip support and the position of the lower lip. The overbite should be stable due to the favourable Edge-centroid relationship and inter-incisal angle.12 Good buccal intercuspation will also aid stability. The superimposition shows that the lower incisors have come forward into a position once occupied by the incisal edges of the upper incisors which is also considered advantageous for stability.11 The lower inter-canine width has been maintained throughout treatment. The position of the lower incisors was changed during treatment and therefore the option of a lower permanent bonded retainer was discussed with the patient to ensure stability of the treatment result. After discussion on the potential financial implications of regular maintenance of bonded retainers the decision was made for long-term retention with vacuum-formed retainers. The post-treatment PAR score was 2, indicating a 95% reduction.

Acknowledgements I would like to thank all the staff in the Orthodontic department at Queen’s Hospital, Burton-on-Trent, who helped me in the treatment of these two cases. In

particular I would like to thank Mr David Spary for his incredible level of continuing support, guidance and clinical expertise.

References 1. Ricketts RM. Perpectives in the clinical applications of cephalometrics. The first fifty years. Angle Orthod 1981; 51: 115–50. 2. Bolton WA. Disharmony in the tooth size and it’s relation to the analysis and treatment of malocclusion. Am J Orthod 1988; 28: 113–30. 3. Brook PH, Shaw WC. The development of an index of orthodontic treatment priority. Eur J Orthod 1989; 11: 309– 20. 4. Richmond S, Shaw WC, Roberts CT, Andrews M. The PAR index (Peer Assessment Rating) methods to determine outcome of orthodontic treatment and standards. Eur J Orthod 1992; 14: 180–87. 5. Mills JR. The application and importance of cephalometry in orthdodontic treatment. The Orthodontist 1970; 2: 32–47. 6. Jacobsen A. The ‘Wits’ appraisal of jaw disharmony. Am J Orthod 1975; 67: 125–38. 7. Bjo¨rk A. Prediction of mandibular growth rotation. Am J Orthod 1969; 55: 585–99. 8. Skieller V, Bjo¨rk A, Linde-Hansen T. Prediction of mandibular growth rotation evaluated from a longitudinal implant sample. Am J Orthod 1984; 86: 359–70. 9. Patel J, Spary D, Edwards I. Molar double tubes: Enhancing orthodontic mechanics. Orthodontic Update 2011; 4: 31–41. 10. Lapatki BG, Mager AS, Schulte-Moenting J, Jonas IE. The importance of the level of the lip line and resting lip pressure

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in Class II, Division 2 malocclusion. J Dent Res 2002; 81: 323–28. 11. Selwyn-Barnett BJ. Rationale of treatment for Class II division 2 malocclusion. Br J Orthod 1991; 18: 173–81.

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12. Houston WJB. Incisor edge-centroid relationships and overbite depth. Eur J Orthod 1989; 11: 139–43. 13. Gonzales-Ulloa M, Stevens E. The role of chin correction in profile plasty. Plast Reconstr Surg 1961; 36: 364–73.

BOS MOrth cases prize 2011.

This paper describes the orthodontic treatment of two cases awarded the prize by the British Orthodontic Society for best treated cases submitted for ...
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