Laurent Massif

Ventilatory disorders and facial growth: Benefits of early genioplasty

AIM The purpose of this prospective study was to determine whether combined functional genioplasty and orthodontic treatment in patients with vertical mandibular growth can be beneficial not only in achieving an esthetic outcome and orthodontic stability but also for the multi-disciplinary management of oral ventilation. METHODS Twenty-five non-obese adolescents (mean age: 14.6 ± 1.4 years) with vertical excess of the lower third requiring genioplasty received surgery following orthodontic treatment. All were predominantly mouth-breathers despite ENT treatment and rehabilitation. The functional before-after impact of genioplasty was examined in a clinical setting using polysomnography. RESULTS Before genioplasty, 52% of the adolescents presented an upper airways resistance syndrome (UARS) with obstructive hypopnea and poor sleep quality. Three to 6 months after genioplasty, the mode of ventilation shifted from oral to nasal (p < 0.001). Lip seal was significantly restored with no contraction of the labio-mental muscles. All nighttime symptoms improved. The proportion of patients suffering from ronchopathy (pathological snoring), dry mouth and disturbed sleep dropped significantly (p = 0.08, p = 0.001, p = 0.0009, respectively). Respiratory events and sleep pattern became normal. Below, we present two clinical reports involving obstructive sleep apnea syndrome (OSAS). CONCLUSIONS Genioplasty performed during puberty promotes spontaneous lip closure and helps restore nasal ventilation. It improves the obstructive disorder and its manifestations during sleep.

La Classe II, 2 dans tous ses états

Resume Le point commun de toutes les formes cliniques des Classes II, 2 est la supraclusion, le plus souvent en « couvercle de boite », avec inclinaison palatine caracteristique des incisives maxillaires. La severite de la forme clinique depend de l’enveloppe musculaire predominante tant au niveau de la sangle elevatrice qu’au niveau de la levre inferieure. L’empreinte genetique est la, mais se greffent les problemes dysfonctionnels qui compliquent le tableau clinique. Le schema vertical squelettique est tres souvent celui d’une rotation anterieure, mais il peut etre variable tout comme le sens sagittal. L’importance de la Classe II squelettique et dentaire depend des verrous verticaux et transversaux ainsi que de la derive mesiale de l’arcade maxillaire a la suite de la dystopie primitive des canines maxillaires. Dans toutes les Classes II, 2 primitives ou fonctionnelles, l’environnement musculaire est crucial a considerer, tant du point de vue etiologique que sur le plan therapeutique.

Effect of surface functionalization of porous silicon microcavities on biosensing performance

Surface functionalization methods were investigated for their effects on the sensing performances of porous silicon (p-Si) microcavities when used for detection of biomolecules. These microcavities were fabricated to reveal reflectivity pass-band spectra in the visible and near-infrared spectral regime. In one approach, the devices were thermally oxidized and functionalized to ensure covalent binding of molecules. In the second approach, the as-etched p-Si surface was modified with adhesion peptides, isolated via phage display, that present high binding capacity for silicon. Functionalization and molecular binding events were monitored via reflectometric interference spectra as shifts in the resonance peaks of the cavity structure due to changes in the refractive index when a biomolecule is attached to the large internal surface of p-Si. Improved sensitivity was obtained owing to the peptide interface linkers between the p-Si and biological molecules compared to the silanized devices. Investigating the formation of peptide-Si interface layer via X-ray photoelectron spectroscopy, scanning tunneling microscopy, and scanning electron microscopy, we found that peptides form nanometer-thin layers on the Si surface and that their binding energy depends on the sequence of the peptide.

Detection of MMP-8 via porous silicon microcavity devices functionalized with human antibodies

In this work we report on the fabrication of functionalized PSiMc scaffolds that can be used to enhance the detection of MMP-8. Matrix metalloproteinases (MMPs) are the major enzymes that degrade extracellular matrix (ECM) proteins and play a key role in diverse physiological and pathological processes. We are interested in detecting the collagenase-type MMP-8 that is an inflammatory marker in gingival fluid for predicting tooth movement during orthodontic treatment. As presence of an increasing amount of MMP-8 in saliva is directly related with the tooth movement during orthodontic treatment, monitoring continuously the MMP-8 variation is primordial. Porous silicon microcavity (PSiMc) structures were prepared as multilayered stacks of low and high refractive indices and with layer thicknesses in the order of visible light wavelength. Then the PSi surface was functionalized with human antibodies. Both functionalization and MMP-8 infiltration were monitored by specular reflectometry. PSiMc is characterized by a narrow resonance peak in the optical spectrum that is very sensitive to a small change in the refractive index, such as that obtained when a molecule is attached to the large internal surface of porous silicon. The pore dimensions of the used PSiMc structures were evaluated by atomic force microscopy (AFM) and scanning electron microscope (SEM).