the tweed profile - The Charles H. Tweed International Foundation

The “New REP” was retained for 9 months in order to
ensure some bone formation.
NewTom 3G VGI with an effective dose of 50.2 ml
Sievert 28,26 was employed to obtain a scan. The settings
were the following: field of view, 12 in; 110 kV
(AP-LL); 2.00 mA (AP) and 1.00 mA (LL); exposure
time, 5.4 seconds and section thickness, 0.50 mm.
The volumetric data was imported in the NewTom 3G
software and converted in the DICOM format. The
software Osirix (v.3.9.1) was used to perform linear
and bidimensional measures (followed by a volumetric
reconstruction).
• Space volume between mandibular first molars
(volumetric evaluation of inferior molar decompensation):
creation of areas on 5 consecutive
slices between mandibular first molars using
lingual dental surfaces and mandibular inner cortical
bone as references. Osirix Software computed
the volume with the aid of a mathematic algorithm
(Fig. 5- Fig. 6)
All measures were classified as volumetric, skeletal or
dental.
VOLUMETRIC MEASURES
• Palatal volume: creation of areas on coronal slicing,
using the CEJ as the vertical reference and the
PNS as the posterior one. Osirix Software calculated
the palatal volume with the aid of a mathematic
algorithm (Fig. 3- Fig. 4)
Fig. 5: Area traced on a coronal slice for airway volume between
mandibular first permanent molar reconstruction
Fig. 3: Area traced on a coronal slice for palatal volume reconstruction
Fig. 4: Palatal volume reconstruction by Osirix (v.3.9.1) software
Fig. 6: Airway volume between mandibular first permanent molar
reconstruction by Osirix (v.3.9.1) software
SKELETAL MEASURES
Transverse skeletal diameter measured on axial slices
at canine (apex) and molar (mesiovestibular root apex)
level until the end of buccal cortical bone (Fig. 7- Fig.
8)
• Mandibular alveolar bone thickness: measured
both at apex and furcation height as the distance
between the external cortical bone and the inner
one (Fig. 9)
• ANS-PNS: distance between anterior and posterior
nasal spine measured on sagittal slices (Fig. 10)
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