sarpe (2 stages) vs le fort 1 (single stage) approach to complex maxillary deformities a critical...

SARPE (2 stage) vs Le Fort 1 (single stage) Approach to

Complex Maxillary Deformities: A Critical Review and Update

AO North America12th Annual Symposium

Wahsington, DC

1samedi 17 mars 2012

Based on

Short- and Long-Term Stability of SARPE RevisitedAJODO 2011; 138:815-22


SARPE

Samson Assisted Rapid Palatal Expansion


Stability of SARPE

• Dental Cast

★ Northway & Meade AO '97

★ Bays and Greco, JOMS '92

★ Stromberg & Holm, JCS '95

★ Antilla et al, EJO '04

★ Pogrel et al, IJAOOS <92

• P-A ceph (+ dental cast)

★ Byloff & Mossaz, EJO '04

★ Berger et al, AJODO '98

★ Koudstaal et al, IJOMS '09

★ Hino et al, JCS '09 (P-A only)

★ Kuo & Will, OMS CNA '90 (P-A only)

Numerous published studies


©Dr Sylvain Chamberland

Stability of SARPE

Conclusions about stability depend on★What was measured?

★When measurements were made?

Especially whether there were measurements during the sequence as well as before/after?



Goal of This Presentation

•Present further longitudinal data for short- and long-term stability

•Follow-up previous reports★ (Angke east 2006 Scientific Meeting)

★Closer Look at the Stability of SARPE ✓ JOMS 2008; 66:1895-1900



Goal of This Presentation

•Larger sample + 2-years stability data

•Data obtained at 6 time points★The only study with PA ceph and models at multiple

time points



Methods

•Prospective and observational study of SARPE outcomes

•Consecutively treated cases

•Approved by Laval University Ethic Committee

Looking ahead



Experimental sample

•N = 38★ 19, 19

★ Mean age : 24.9 ± 9,7(range 15,1: 53,7) 0

2

5

7

9

-,17] (17, 20] (20,25] (25,30] (30,35] (35, +

6

5

2

9

7

9

Distribution

# o

f p

atie

nts

Âge

# cas



Observation Time Point N Mean time (months)

S-D Min. Max.

T1-T2 (Distraction completed) 38 0,68 0,23 0,46 1,81

T2-T3 (Expander retention) 38 5,95 0,68 4,21 7,13

T1-T4 (Start to 2nd surgery) 32 15,27 3,99 9,40 24,28

T2-T5 (End expansion to deband) 37 21,59 5,28 12,88 41,69

T3-T5 (Expander out to deband) 37 15,64 5,09 7,79 35,19

D1-T5 (Total treatment time) 37 23,57 5,27 15,41 43,07

T5-T6 (Post ortho treatment) 23 25,35 4,49 20,96 39,49

Dental cast + PA ceph



• Of the 38 who completed the distraction phase

• 32 had a 2nd surgical phase planned

• 4 of them did not need it after reassessment

• 1 was over-expanded and needed constriction of the maxilla at the 2nd surgical phase to achieve arch coordination

✦ His data were removed at T5

• 23 patients have returned for records 2-years after the end of orthodontic treatment



Tooth-borne Expansion Device

•Superscrew™

•Banded; N = 21

•Bonded; N = 17

A

B



Our SARPE Technique

Zygomatic buttress

Piriform rim

Widening of the osteotomy cut: → lateral rotation hemimaxillae

Piriform rim

Zygomaticomaxillary

Pterygomaxillary junction

Mid-palatal suture



Separation of thepterygoid junction

Separation with osteotome of the midpalatal suture

Per-op diastema of 1 to 1,5 mm

Our SARPE Technique Piriform rim

Zygomaticomaxillary buttress

Pterygomaxillary junction

Midpalatal suture



Treatment modality

•Appliance cementation: 1 day to 1 week prior to surgery

•Latency period: 7 days

•Distraction period: 0,25 mm bid

★14 to 21 days; monitored twice a week

•Tx initiated in the mandibular arch 1 week to 2 months before SAPRE



Treatment modality

•Brackets bonded in maxillary arch 2 months after expansion is stopped

•Expander removal: 6 months after expansion is stopped

•No other retention except the main arch wire

•At debonding: bonded lingual wire 3-3 only, ↑&↓



• Study cast

• Dental width changes

• Screw width

• Diastema

Outcome Measures

• Standardized PA ceph• DPI set to obtain 1:1

• Screw width in situ vs screw width on the ceph

★ T1: r = 0,99164

★ T2: r = 0,98955

• Nasal cavity width

• Mx width: Jr-Jl

• Screw changes17samedi 17 mars 2012


Statistics

•Paired 2-samples T-tests✓Bonferroni method: α = 0.05/6

•Repeated measures ANOVA

•Unpaired 2 samples T-tests

•Pearson's correlation coefficients

•Shrout and Fleiss's intraclass correlation = 0,99 coefficient of fidelity

Refer to the article for more details about stats


Results



Changes in arch dimensions

Maximal expansion T3-T1Relapse T5-T3Net expansion T5-T1Long term relapse T6-T5Net changes T6-T1

• Significant: p < 0.001

★ Expansion T3-T1

★ Relapse T5-T3

★ Net expansion T5-T1

★ 2-years recall T6T1

Canine

1st premolar

2nd premolar

1st molar

2nd molar

1st lower molar, Non exo subgroup

1st lower molar, Exo subgroup

-4 -3 -1 1 2 4 5 7 8

"

Changes (mm)20samedi 17 mars 2012


Changes in skeletal width

• Significant skeletal expansion

★ Mx & Nasal cavity (p < 0.0001)

• Changes T5T3: NS (p=0,1166)

• Skeletal changes = STABLE

0

1,00

2,00

3,00

4,00

5,00

6,00

7,00

8,00

0,68 6,632 15,27 23,57 48,920

11

23

34

46

57

69

80

4146

56

65

80

Changes over time post SARPE

Exp

ansi

on (m

m)

Time point (months)

% S

kele

tal e

xpan

sion

∆ 1st Molar∆ Nasal Cavity∆ Mx% ∆ Mx/∆ M1



Other outcomes

•Type of expansion device: Bonded vs 2-bands★ Same efficacy for skeletal & dental expansion (No difference: p=0,2727)

★ Same dental relapse (No difference: p=0,5052)

•Effect of phase 2 surgery on transverse relapse at the 1st molar★ No significant effect of any phase 2 surgery (No difference: p=0,6637)

★ Or any combination of phase 2 surgery



Effect of time on relapse after appliance removal

•Significant relationship between the amount of relapse seen after SARPE and the time the post treatment observation was made

Time point comparisonTime point comparison Relapse (mm) Error T or F value DF P value

T3 vs T4 vs T5 vs T6 T3 vs T4 vs T5 vs T6 T3 vs T4 vs T5 vs T6 28.98 (F) 3, 125 <0.0001

T3 vs T4 (9,5 ± 3,2 m)T3 vs T4 (9,5 ± 3,2 m) -1,05 0,30 3,53 (T) 125 0,0006

T4 vs T5 (5,7 ± 1,5 m)T4 vs T5 (5,7 ± 1,5 m) -0,79 0,30 2,62 (T) 125 0,0098

T3 vs T5 (15,2 ± 5,1 m)T3 vs T5 (15,2 ± 5,1 m) -1,85 0,29 6,43 (T) 125 <.0001

T5 vs T6 (24,7 ± 3,1 m)T5 vs T6 (24,7 ± 3,1 m) -1,09 0,34 3,23 (T) 125 0,0016



Effect of time on relapse after appliance removal

• 57% of the total relapse occurred during the 1st 9 months after expander removal

• 43% occurred in the following 6 months

•Another 1 mm or so occurred 2 years after debonding

Time point comparisonTime point comparison Relapse (mm) Error T or F value DF P value

T3 vs T4 vs T5 vs T6 T3 vs T4 vs T5 vs T6 T3 vs T4 vs T5 vs T6 28.98 (F) 3, 125 <0.0001

T3 vs T4 (9,5 ± 3,2 m)T3 vs T4 (9,5 ± 3,2 m) -1,05 0,30 3,53 (T) 125 0,0006

T4 vs T5 (5,7 ± 1,5 m)T4 vs T5 (5,7 ± 1,5 m) -0,79 0,30 2,62 (T) 125 0,0098

T3 vs T5 (15,2 ± 5,1 m)T3 vs T5 (15,2 ± 5,1 m) -1,85 0,29 6,43 (T) 125 <.0001

T5 vs T6 (24,7 ± 3,1 m)T5 vs T6 (24,7 ± 3,1 m) -1,09 0,34 3,23 (T) 125 0,0016



Correlation between variables• 2 variables are significantly correlated with the amount of

expansion of 1st molar at T3

★ Diastema at the end of expansion (r2 = 0,41; p < .0001)

★ Change in length of the screw during expansion (r2 = 0,88; p < .0001)

•Dental changes are not correlated with skeletal changes (r2 = 0,11; p = 0.0381) (supported by Goldenberg et al)


Discussion



Short term stability

•Expansion of 1st molar = 7,6 ± 1,57 mm★Similar to other reports measuring to the maximum

expansion point✓ Pogrel et al, Byloff and Mossaz, Koudstaal et al, de Freitas et al

•Significant relapse for all teeth (canine to 2nd molar)

•Mean relapse at 1st molar = 1,83 ± 1,83 mm★24% of the maximum expansion; large std. dev.



Short term stability

•Post treatment retention is an important factor

•In this study: expansion device maintained 6 months



Experimentals (n=38; 37;23)

Byloff and Mossaz, (n = 14)

de Freitas et al, 2008 (n = 20)

Koudstaal et al, 2009 (n = 19) T-B

Koudstaal et al, 2009 (n =23) B-B

Berger et al, 1998 (n=28)

Pogrel et al, 1992 (n=12)

-4,00 -3,00 -2,00 -1,00 0 1,00 2,00 3,00 4,00 5,00 6,00 7,00 8,00 9,00

4,57

7,50

5,78

5,20

6,80

8,06

8,70

7,60

6,62

4,77

4,60

6,30

7,12

5,54

5,73

-0,88

-1,01

-0,60

-0,50

-1,48

-3,16

-1,83 -0,99

mm

12 months study period

Comparison to Other Short-Term

Long Term Relapse Short Term Relapse Net expansionMaximum expansion Long term exp

≠Pterygoid + T2 = before Phase2 surgery

≅Exp.

12%

17.5%

24%

18%

11%

11%

36%



Those 12 months study period

•Concluded that expansion was stable

•But all their patients were still in orthodontic treatment



Our Study = 49 Months

•Data at T4 were collected 15 months post-SARPE, prior to 2nd surgical phase for those who needed one

•Relapse at T4 = 57% of the relapse we found

•Therefore, any inferences about the stability of SARPE is questionable if arch form coordination or final AP or vertical relationships have not achieved at the time of measurements



In Our Study

• 42% of the patients have a relapse of 2 mm

• 22 % of a relapse > 3 mm

• This is similar to multisegmented Le Fort 1

0 %

5,0 %

10,0 %

15,0 %

20,0 %

25,0 %

30,0 %

35,0 %

40,0 %

45,0 %

50,0 %

'-,-3] (-3 to -1] (-1 to 1] (1 to 3]

SARPE: Post-Tx changes

% o

f pat

ient

s

Relapse (mm)

First MolarFirst Premolar

42%

22%



Long term stability

Canine

1st premolar

2nd premolar

1st molar

2nd molar

-4 -3 -1 1 2 4 5 7 8

"

Changes (mm)

Maximal expansion T3-T1Long term relapse T6-T5Net changes T6-T1

•Data at T6 = 24,7 ± 3 m

•Relapse NS

•Relapse S : 1st Molar ★= 0,99± 1,1 mm; p= 0.0003

★17% of net expansion at T5 that adds to relapse T5T3



Long term stability

Canine

1st premolar

2nd premolar

1st molar

2nd molar

-4 -3 -1 1 2 4 5 7 8

"

Changes (mm)

Maximal expansion T3-T1Long term relapse T6-T5Net changes T6-T1

• Cannot be explained by type 1 error (α = 0.05/6)

• Cannot be explained by the effect of a bonded vs banded appliance

• Post treatment arch form adjustment may be the explanation since on the average, lower molar distance was expanded and constricted modestly and a large std dev was noted (-0,18 ± 1,5 mm)



Experimentals (n=38; 37;23)

Antilla et al, 2004 (n=20; 13)

Stromberg & Holms, 1995 (n=20)

Nortway & Meade, 1997 (n=16)

Bays & Greco, 1992 (n=19)

-2,25 0 2,25 4,50 6,75 9,00

5,9

4,577,60

5,78

5,50

8,30

7,20

5,73-1,83

-0,45

-0,22

-1,20

-1,30

-0,99

mm

Comparison to Other Long-Term Studies

Long Term Relapse Short Term Relapse Net expansionMaximum expansion Long term exp

≅Exp.6%

7%

8.3%

17%

22%

2,4 y

5 y

3,5 y

6 y

2 y



Skeletal Expansion & Stability

• Immediately after SARPE about half (46%) of the expansion was skeletal

• This is more than Byloff & Mossaz, Berger et al

★ Appliance was removed after 3 months instead of 6 months

• Hino et al (JCS 2008) reported larger skeletal expansion (~ 6,3 to 6,9 mm) but used landmark closer to the teeth



• Skeletal expansion ranging from 1,3 to 7 mm

✦ Loddi et al, Landes et al, Goldenberg et al, Tausche et al, Zemann et al, Lagravere et al

✦ Koudstaal et al (IJOMS 2009) obtained 3,1 ± 2 mm of expansion at alveolar crest and 2,6 ± 1,8 mm at nasal level

✦ Lagravere et al (AJODO 2010) CBCT study

✓ BAME = 1,3± 1,4 mm vs TAME = 1,83± 1,69 mm at the outer cortex of alveolar bone

• There was no difference between TB and BB appliances (12 month study period)

CBCT study



•If one look at skeletal changes, it should rank high in the hierarchy

•But if one looks at dental changes★64% of the patients have > 2 mm change

★22% have > 3 mm changes

Stability?0 %

10,0 %

20,0 %

30,0 %

40,0 %

50,0 %

'-,-3] (-3 to -1] (-1 to 1] (1 to 3]

SARPE: Post-Tx changes

% o

f pat

ient

s

Relapse (mm)

First MolarFirst Premolar



•This could be attributed to★The device itself

★The surgical technique

★The timing of observation

Stability?



•For all other surgery★Presurgical orthodontic preparation is done

★Few if any dental movements need to be accomplish after surgery

•This is not the case for SARPE★Many dental movement are done after expander

removal including correction of overexpansion

Stability?



SARPE and other surgical procedure

• It is appropriate to focus on skeletal, not dental stability— which has not been clearly reported previously because appropriate P-A ceph were not available at multiple time point



Related variables

•Correlation between the width of the diastema at the end of distraction (T2) and the amount of 1st molar expansion at T3 indicates that the adequate molar expansion is occurring

• If no diastema appears ➙ no separation of the hemimaxillae and tipping of buccal segment is occurring



Related variabless

•Dental changes are not correlated with skeletal changes (r2 = 0,11; p = 0.0381) (supported by Goldenberg et al)

• In frontal view, rotation of the hemimaxillae occurs

★Teeth expands more widely than the bone

★Palatal depth decrease

•No significant relationship between the amount of expansion and the amount of relapse (r2 = 0,07; p = 0.1186)



Before Expansion

After ExpansionA

B

CC



lAs the appliance is activated,note that the hemimaxilla move inwardrelatively to the upper part

lThis may explain why CBCT study may find less skeletal expansion than PA ceph because of the precision of the landmarks



Phase 2 surgery

• A classic study of the stability of transverse expansion obtained with segmented Le Fort 1 reported that patients who had concurrent mandibular surgery had significantly greater relapse at the 1st and 2nd molar

• Our data show no significant effect of any phase 2 surgery on dental relapse

• This might be an important decision factor if large transverse changes are necessary along with vertical and AP changes



Conclusion

•Skeletal change were modest (3-4 mm) but stable

•Relapse in dental expansion was almost totally attributed to lingual movement of posterior teeth



Conclusion

•Phase 2 surgery did not affect dental relapse

•Diastema at the end of distraction is a predictor that adequate molar expansion is occurring

•Bonded expanders show the same efficacy as banded expanders.



Conclusion

•Doing 2 phase surgery (SARPE + Bimax surgery) thinking that the transverse changes will be more stable than Le Fort 1 changes is not warranted

•When maxilla need to be repositioned AP or vertically in a 2nd phase ★Decision should be based on the risk, morbidity & cost of 2

surgery versus risk, morbidity & cost of 1 stage segmental Le Fort 1 for large expansion along with vertical and AP changes



Conclusion

•Most of the transverse change of 5-6 mm the maxilla can be corrected by a segmented Le Fort 1

•Expansion greater than 6-7 mm is an indication for SARPE



Le Fort 1 Morbidity

•Pulpal necrosis

•Periodontal defectsB

A



• Aseptic necrosis

★ Most likely to occur with Le Fort 1 osteotomies done in multiple segments in conjonction with superior repositioning and transverse expansion

Le Fort 1 Morbidity

Lanigan et al, J Oral Maxillofac Surg 48: 142-156, 1990

Courtesy of Dr Brian Alpert



• Nasopalatal cyst

• Fibrous healing

SARPE MorbidityA B

A B



• Asymmetric fracture of interdental septum + gingival defect

• Non-separation of the pterygoid junction or attempting too much expansion (3mm) intraoperatively may lead to aberrant fracture that can run to the base of the skull, orbit and pterygopalatine fossa

Lanigan DT, Mintz SM, J Oral Maxillofac Surg 60: 104-110, 2002

Cureton SL, Cuenin M, AJODO, 1999

SARPE Morbidity



Clinical Implications

• If only transverse changes are needed★ SARPE = Choice # 1

MC; tx:18m Ka.Ri. Tx: 103w



SARPE may be indicated

• For very large transverse (>6 mm), AP and vertical changes or periodontally compromised patients

(Personal opinion)



Retrospective look

• This case would have had an excellent outcome with exo of 5's/5's and 1 phase surgery that would include segmented Le Fort 1 & BSSO

• Nevertheless, a non extraction 2 phase surgery was done

Ka.Tr.271107

Ka.Tr.210909



Retrospective look

• 2 years post treatment

✦ Some bite opening occured

✓ As the transverse relapse, Mx incisors may procline to accomodate

• Therefore, we can not conclude that 2 phase surgery was any better than 1 phase surgery for this particular case

Ka.Tr.120911



Case 1

• Class I ( cl III tendency)

• Mx constriction

• Moderate to severe crowding

• Heavily restored teeth

Ka.La.270510



• Moderate apnea, severe snoring

• Orthodontic Tx plan: exo 5's/5's

• Surgical Tx plan = Mx & Md advancement



Progess reports

• Reassessment of bracket position

• Mx: 3 segments

• Md: finishing space closure

• Surgery in May

Ka.La.120312



• Decompensation of the dentition is done

• Surgical tx plan will focus on skeletal changes



Case 2

• Class III

• Severe Mx constriction Ω

• Could this case be treated in 1 phase surgery?

✦ YES. (exo 15, 24 / non ex)

St.Gi.191009

37,12

33,52



• Retrusive maxilla

• Retroclined /1

• Md laterodeviation to the left



• Pre-surgical

✦ Segmented Le Fort 1: to constrict!

✦ Md set back and laterodeviation

✦ Surgery tomorrow...

St.Gi.221111

43,85

41,26



• /1: proclined by 12°

• 1/: retroclined by 10°

St.Gi.221111



St.Gi.211211;

29 days post surgery

St.Gi.061211;

14 days post surgery



• Finishing stages

• Tooth mass discrepancy may help to explain the cl II canine relationship

• Significant arch width improvement

43,85

St.Gi.221111

33,52

St.Gi.191009 St.Gi.130212

40,07

St.Gi.130212

St.Gi.120312



Case 3

• Class III

• Mutilated dentition

• Moderate Mx constriction

• Overerupted UL6

Hé.Ar.030909



• Retrusive maxilla

• Proclined 1/

• Retroclined /1



• TADs

✦ Mx: to intrude UL6

✦ Md: to get some protraction of LL8



Pre-Surgical

• Edentulous space prepared

• Surg. Plan:

✦ Mx: Le Fort 1 advancement

✦ Bone graft at implant site

Hé.Ar.171111



• Mx: Le Fort 1 to advance

• Md: Genioplasty to correct the chin déviation



• 17 days post surgery

Hé.Ar.160511



At 121 weeks

• Crowns are scheduled next month

• Operative dentistry will follow

Hé.Ar.250112



• Bridge and crown placed today

• Total Tx time 128 weeks

Hé.Ar.120312



Class 4

• Anterior open bite

• Moderate crowding

Ma-Je.Be210808



• Slight vertical maxillary excess

• Bimaxillary protrusion

• Lip incompetency

Ma-Je.Be210808



Tx Plan

• Would you do SARPE?

• Would you plan a non extraction approach?

• Would you extract?

• Would you plan a segmented Le Fort 1?

• Would you plan a 1 piece Le Fort 1?

• My plan:

✦ Exo of 5's

✦ Bimaxillary surgery



At 85 weeks

• Normal OJ & OB

• Class I molar and canine relationship

• Midline coincident

Ma-Je.Be300410



• Retracting and uprighting the incisors helped to close the bite

• Slight maxillary excess



At 109 weeks20 weeks post surgery

• Class I occlusion is achieved

Ma-Je.Be210808

Ma-Je.Be131010



• Mx: Le Fort 1: superior repositionning & advancement

• Md: BSSO & genio



Case 5

• Narrow maxillary arch

• Cl II div 1, open bite

• Avulsion 22, fractured 11, 21

• Exfoliation 74, missing 35

Lu.Mo.030708



• Retrognathic mandible

• Bimaxillary protrusion

• Lip incompetency



Tx Plan

• Would you do SARPE?

• Would you plan a non extraction approach?

• Would you extract?

• Would you plan a segmented Le Fort 1?

• Would you plan a 1 piece Le Fort 1?



Tx Plan

• Exo of 5's & E

• Mx Le Fort 1

✦ Impaction, advancement, expansion

• Md: BSSO

• Genio advancement



Lu.Mo.200409

At 36 weeksMx: Step distal to the canine. Prothetic tooth bonded to a bracketMd: En masse retraction

At 85 weeksMx: 3 segmentsMd: Spaces closed•Surgery in June

Lu.Mo.010410



• Incisors were retracted, no extrusion



Presurgical models

• Selective grinding to maximize toot contact

• Left posterior Xbite noted

✦ Expansion needed



• Surgery at 96 weeks

✦ Le Fort 1: advancement 3,5 mm, impaction 3,5 mm, expansion 1,6 mm

✦ BSSO: advancement 8 mm; genio: advancement 6 mm, vertical reduction 2,5 mm

• At the removal of the surgical splint

✦ Note lack of posterior occlusal contact

Lu.Mo.010710



Osteotomy half way between apices of the teeth and infraorbital nerve

Rigid fixation to the piriform rim & zygomatic buttress buttress

Courtesy Dr Carl Bouchard

Osteotomy sites filled with bone from the slice removed at the symphysis

DL 130312



BSSOBicortical screw

Courtesy Dr Carl Bouchard

GenioplastyPre-bended 6 mm monocortical plate



• Tx time = 123 weeks

• Implant #22 was placed

Lu.Mo.201210



• Nice profile

• Lips are competent



• At 28 weeks into retention

✦ Crown is placed on #22

• At 60 weeks into retention

✦ Note some midline deviation to the right and slight cl II

Lu.Mo.070711

Lu.Mo.130112



• Recall at 60 weeks



Why I don't like rigid fixation for a genioplasty

Poor contact between distal & proximal segment

Screw EmbedLu.Mo.010710 Lu.Mo.130212

Note bone formation over superior portion of fixation device and resorption in area of inferior

portion of fixation device

Screw in the resorptive zone

Apposition zone

Screw prominent



Courtesy Dr Dany Morais

Why do I prefer osteosynthesis?

Resorptive zone

R: RemodelingA: Apposition

De.Le060608 De.Le130410

Resorptive zone

Apposition zone

Improved contact between proximal and distal segment

Precious D., Armstrong J., Morais D., Anatomic placement of fixation device in genioplasty, OOO 1992,; 73-2-8

Note complete coverage of fixation wires by bone and smooth labial

cortical bone of anterior manbible



Why I don't like posterior openbite after orthognathic

surgery?

• Lack of posterior occlusion may increase pressure at the condyle and cause non-physiologic remodeling or condylar resorption

Jam-packedScrewed Setting occlusion

Pressure

The bite openSlight progressive

retrusion

Condyle resorb


Distinguished AttendeesThank you

www.slideshare.net/sylvainchamberlandwww.sylvainchamberland.com


http://www.slideshare.net/sylvainchamberland

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• Mx: segmented Le Fort 1

✦ Advancement

✦ Anterior elongation

✦ Expansion

• Md: BSSO + genio


sarpe (2 stages) vs le fort 1 (single stage) approach to complex maxillary deformities a critical...

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antilla et

hino et

pogrel et

dental cast northway

stage vs

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