This study indicates that scanning of the human face may be hampered by errors and artefacts, mainly due to movements. While the effect of trembling and involuntary movements during the exam may be minimized using faster scanning devices, comparative observation over time may be affected by unreal differences due to the uncertainty of facial expression. The overall error is, however, in the range useful for most clinical studies.
Quantifying soft tissue changes after orthognathic surgery is increasingly important in surgical planning, but little is actually known about the changes in facial mobility after surgery. In the current study, we investigated facial mimics in patients before and after orthognathic surgery. Eleven patients with jaw discrepancy requiring maxillary and/or mandibular surgery were considered. Facial landmarks were applied, and facial surface data were acquired using a three-dimensional laser scanner before surgery and after 3, 6, and 12 months. The facial movements were frowning, eye closure, grimace, smiling, and lip purse. They were described in terms of surface and landmark displacements. Mean and SD were calculated for the right and left sides of the face and compared with normal values previously obtained in control subjects. We compared the results in 4 groups of patients: all the patients together (group A), bimaxillary surgery (group B), basal surgery without ancillary procedures (group C), and basal surgery plus rhinoplasty and/or genioplasty (group D). After surgery, modifications of symmetry were evident in many subjects, but after 1 year, facial movements were statistically similar to presurgical registrations. In smiling, the single case observations revealed a postsurgical improvement of amplitude in 8 subjects. In conclusion, orthognathic surgery did not significantly modify facial mobility in the long term. On the contrary, the amplitude of movement during smiling seems to increase in the majority of subjects. Our evaluation of three-dimensional laser scanning of facial movement showed that it can detect small posttreatment changes on soft tissues.
Skin is an important region of somatic sensory input, and is one of the most innervated areas of the human body. In this study, we investigated in human hand skin the distribution of nervous structures immunoreactive for the growth-associated protein 43 (GAP-43) and the protein gene product 9.5 (PGP 9.5). GAP-43 is a neuronal presynaptic membrane protein that is generally considered to be a marker of neuronal plasticity. PGP 9.5 is a neuron-specific soluble protein that is widely used as general marker for the peripheral nervous system. The entire neural network of the dermis and epidermis was stained with antibody to PGP 9.5. In the dermis, there were fewer GAP-43-immunostained nerve fibers than PGP 9.5-immunostained nerve fibers, whereas in the epidermis the numbers were equal. Only some Merkel cells and Meissner corpuscles were GAP-43-immunoreactive. In conclusion, our results show that GAP-43 protein is expressed in a subset of PGP 9.5-immunoreactive nerve structures. Anat Rec Part A 272A: 467-473, 2003.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.