Table 5 Stress distribution (MPa) at the maxillofacial sutures and landmarks after activation of the quad-helix and NPE2 appliance

Mid-palatal suture

 Point A

0.317823

0.317135

 Point B

0.969081

0.786962

 Point C

2.433233

1.896292

 Point D

0.000522

0.00446

Maxillofacial landmarks

 Point A

0.434458

0.409881

 ANS

0.060478

0.059042

 PNS

0.022241

0.01746

 Maxillary tuberosity

0.252454

0.189975

 Pterygoid hamulua

0.429192

0.375754

 Infra-orbital rim

1.029457

0.976392

 Frontal process of zygomatic bone

0.502464

0.460146

 Maxillary process of zygomatic bone

0.55113

0.509731

 Temporal process of zygomatic bone

1.053598

0.9987

 Lateral nasal wall

1.219208

1.165219

 Inferior nasal floor

0.095343

0.100366

 Lateral pterygoid plate

0.21982

0.200389

 Fronto-maxillary suture

0.000932

0.000812

 Zygomaticomaxillary suture

0.005582

0.005473

 Fronto-zygomatic suture

0.075531

0.067953

 Fronto-nasal suture

0.020907

0.017968

 Zygomatico-temporal suture

0.039584

0.03841

 Pterygo-maxillary suture

0.012675

0.007898

 Inter-nasal suture

0.06921

0.071998

 Naso-maxillary suture

0.002441

0.002493