Stereophotogrammetric evaluation of tooth-induced labial protrusion.
OBJECTIVE
To better manage dental treatment outcome, a previsualization of desired appearances can be used to understand patients' wishes. A deeper comprehension of labial modifications related to hard-tissue movements is advantageous. The purpose of the study was to evaluate tooth restoration-induced labial displacements in three dimensions.


METHODS
In a group of 20 healthy Caucasian individuals, simulations of vestibular translations of maxillary anterior crowns were obtained by placing an acrylic resin veneer on the labial surfaces of maxillary incisors and canines. Three-dimensional stereophotogrammetric acquisitions were made to evaluate soft-tissue changes induced by the simulations. Linear dislocation of selected landmarks and labial surfaces were quantified using dedicated software.


RESULTS
All paired and two midline labial landmarks had significant displacements, ranging from 13% (Subnasale landmark) to 103% (left Cheilion landmark) of veneer thickness (2 mm thick). A significant positive correlation was obtained between the lower lip displacement and overjet values.


CONCLUSIONS
The vestibular shift of maxillary incisors and canines affect both upper and lower vermilion areas, without involving cutaneous perilabial landmarks.
Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale dell'Apparato Stomatognatico (LAFAS), Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milan, Italy.
Riccardo
R
Rosati
Marcio
M
De Menezes
Ana Maria Bettoni Rodrigues
AM
da Silva
Alberto
A
Rossetti
Giuseppe C
GC
Lanza Attisano
Chiarella
C
Sforza
D000180:Acrylic Resins / Q000737:chemistry; D000328:Adult; D059925:Anatomic Landmarks / Q000033:anatomy & histology; D002508:Cephalometry / Q000379:methods; D002680:Chin / Q000033:anatomy & histology; D003198:Computer Simulation; D003442:Crowns; D003481:Cuspid / Q000033:anatomy & histology*; D003764:Dental Materials / Q000737:chemistry; D003801:Dental Veneers; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000033:anatomy & histology*; D008046:Lip / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D009666:Nose / Q000033:anatomy & histology; D057887:Overbite / Q000473:pathology; D010347:Patient Care Planning; D010780:Photogrammetry / Q000379:methods; D013499:Surface Properties; D055815:Young Adult
D000180:Acrylic Resins; D003764:Dental Materials
3D; lips; orthodontics; prosthesis; stereophotogrammetry