3D soft-tissue, 2D hard-tissue and psychosocial chantes following orthognathic surgery

A 3D imaging system (C3D®), based on the principles of stereophotogrammetry, has been developed for use in the assessment of facial changes following orthognathic surgery. Patients’ perception of their facial appearance before and after orthognathic surgery has been evaluated using standardised questionnaires, but few studies have tried to link this perception with the underlying two-dimensional cephalometric data. Comparisons between patients’ subjective opinions and 3D objective assessment of facial morphology have not been performed. Aims: (1) To test the reliability of the 3D imaging system; (2) to determine the effect of orthognathic surgery on the 3D soft-tissue morphology; (3) to assess skeletal changes following orthognathic surgery; (4) to evaluate soft-tissue to hard-tissue displacement ratios; (5) to ascertain the impact of orthognathic surgery on patients’ perception of their facial appearance and their psychosocial characteristics, (6) to explore the dentofacial deformity, sex and age on the psychosocial characteristics; (7) to evaluate the extent of compatibility between the cephalometric and the three-dimensional measurements and (8) to determine if the magnitude of facial soft-tissue changes affects the perception of facial changes at six months following surgery. Results and Conclusions: C3D imaging system was proved to be accurate with high reproducibility. The reproducibility of landmark identification on 3D models was high for 24 out of the 34 anthropometric landmarks (SD£0.5 mm). One volumetric algorithm in the Facial Analysis Tool had an acceptable accuracy for the assessment of volumetric changes following orthognathic surgery (mean error=0.314 cm3). The error of cephalometric method was low and the simulation of mandibular closure proved to be reproducible. 2D soft-tissue measurements were compatible with 3D measurements in terms of distances, but angular measurements showed significant differences (p<0.05)

The soft-tissue profile preferences of a group of lay persons and professionals

Magister Chirurgiae Dentium - MChDAlthough facial aesthetics has always been a part of orthodontic diagnosis and treatment planning, the criteria for facial evaluation have been somewhat arbitrary. They are often based on parameters from the field of art or from evaluating faces chosen by orthodontists or other professionals. The aims and objectives of the study were to determine the soft-tissue profile preference of a group of lay persons and professionals; to compare the preferences of the male and female assessors (lay persons group) with regard to the preferred profiles for the maleand female patient respectively; to test similarities and differences in the professional's perceptions of the various profiles. This qualitative study was undertaken at the orthodontic clinic at UWC using post-treatment soft tissue profile photographs of patients who had attended the orthodontic clinic.South Afric

A photometric soft-tissue profile assessment in a Western Cape sample

Magister Chirurgiae Dentium (MChD)Cephalometric norms for the soft-tissue profile presently utilized in this country, are based almost entirely on North American Caucasian and Negroid studies. Orthodontists use these standards as a guide in the treatment of all sections of the South African population. Various studies have conclusively shown that the soft-tissue profile differs both racially, and from country to country. In recent years the number of patients presenting for orthodontic treatment at the University of the Western Cape has increased significantly. The need has therefore arisen for the establishment of soft-tissue profile trends in the Western Cape area

Clinicians’ Perception of the Benefit from Orthognathic Surgery in Patients of Different Racial Background Presenting with a Class III Skeletal Discrepancy

Aim: To investigate the impact of patients’ race on influencing whether clinicians perceive benefit from orthognathic surgery in patients with class III skeletal bases. Design: Cross-sectional study. Methods: This study involved sending questionnaires to all consultant orthodontists and maxillofacial surgeons in the United Kingdom using the mailing list from British Orthodontic Society and British Association of Oral and Maxillofacial Surgeons. The questionnaires were sent using a sequential mixed mode approach for the Consultant Orthodontists group and a web-based mode for the Oral and Maxillofacial Surgeons group. The questionnaire used silhouettes of two patients (one Caucasian and one Chinese). These were manipulated to produce a class III skeletal discrepancy. The maxillary position of the selected normal profile silhouettes was manipulated posteriorly from the normal position, in 2 mm increments up to 10 mm. The mandibular position, of the selected normal profile silhouettes, was manipulated anteriorly from the normal position, in 2 mm increments up to 10 mm. A total of 26 silhouettes were constructed. The participants were asked to spend no more than 30 seconds looking at the silhouettes and answer the following questions: “Do you think that a patient, presenting with this profile, would benefit from orthognathic surgery?” and “How do you rate the level of attractiveness of the profile?” Results: There was no statistically significant difference between the perception for the benefit from orthognathic surgery between Consultant Orthodontists’ and Consultant Oral and Maxillofacial Surgeons (p=0.176). The silhouette’s race was featured as highly statistically significant factor predicting the perceived benefit from surgery (p<0.001). The odds of clinicians perceiving a benefit from surgery and therefore recommending an orthognathic surgery approach increased 2.87 times for a Chinese silhouette compared to a Caucasian silhouette with class III skeletal bases. Consultant’s years of experience, gender, specialty, the number of orthognathic patients treated per year, and the consideration of the importance of an attractive appearance were not statistically significant factors predicting perceived benefits from orthognathic surgery. Conclusion: Clinicians perceived benefit from orthognathic surgery in patients with class III skeletal bases was significantly higher for Chinese silhouettes than for Caucasian silhouettes with the same degree of manipulation. The Caucasian ideal profile was considered more attractive than the Chinese ideal profile

PRELIMINARY FINDINGS OF A POTENZIATED PIEZOSURGERGICAL DEVICE AT THE RABBIT SKULL

The number of available ultrasonic osteotomes has remarkably increased. In vitro and in vivo studies have revealed differences between conventional osteotomes, such as rotating or sawing devices, and ultrasound-supported osteotomes (Piezosurgery®) regarding the micromorphology and roughness values of osteotomized bone surfaces. Objective: the present study compares the micro-morphologies and roughness values of osteotomized bone surfaces after the application of rotating and sawing devices, Piezosurgery Medical® and Piezosurgery Medical New Generation Powerful Handpiece. Methods: Fresh, standard-sized bony samples were taken from a rabbit skull using the following osteotomes: rotating and sawing devices, Piezosurgery Medical® and a Piezosurgery Medical New Generation Powerful Handpiece. The required duration of time for each osteotomy was recorded. Micromorphologies and roughness values to characterize the bone surfaces following the different osteotomy methods were described. The prepared surfaces were examined via light microscopy, environmental surface electron microscopy (ESEM), transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM) and atomic force microscopy. The selective cutting of mineralized tissues while preserving adjacent soft tissue (dura mater and nervous tissue) was studied. Bone necrosis of the osteotomy sites and the vitality of the osteocytes near the sectional plane were investigated, as well as the proportion of apoptosis or cell degeneration. Results and Conclusions: The potential positive effects on bone healing and reossification associated with different devices were evaluated and the comparative analysis among the different devices used was performed, in order to determine the best osteotomes to be employed during cranio-facial surgery

Analiza uticaja ortodontskog i ortodontsko-hirurškog lečenja na gornje vazdušne puteve i meka tkiva lica primenom kompjuterizovane tomografije

Three-dimensional (3D) nature of the human body and head had been analysed ever since the antient times. At the beginning of the 20th century plaster was the basic diagnostic material used for representing dentofacial morphology, so most orthodontists used plaster study models to analyse the dentition and the alveolar bone. Some more ambitious clinitians, amongst them Calvin Case, even suggested the use of facial moulages in order to capture the pre- and posttreatment facial morphology. Introduction of cephalometrics to orthodontics in the mid 1920-ies enabled describing craniofacial morphology and growth, predicting growth, planning treatment and evaluating treatment outcomes. However, even back in the 1960-ies orthodontists recognized a need for 3D cephalometrics. Craniofacial CBCT scanners were developed at the beginning of the 21st century in order to overcome limitations of conventional CT scanners. CBCT enabled us to analyse skeletal and soft-tissue structures of our patients in all three dimensions of space and as 3D volumes using the data from a single scan which exposes the patient to significantly less radiation then the conventional CT scanner. The aim of this doctoral dissertation was to analyse upper airway and facial soft-tissue changes of adolescent patients treated orthodontically with or without extractions, and adult patients treated by combined orthodontic-surgical treatment. The sample consisted of 107 patients treated at the Department of Orthodontics and the University Hospital of the Case Western Reserve University in Cleveland, OH, USA. All patients were scannen before and after treatment, as a part of the standard diagnostic and therapeutic procedure, using an adjusted Hitachi CB MercuRay scanner (2 mA, 120 kV, 12‖ FOV, F Mode). Depending on the type of treatment patients were divided into three groups. Cephalometric analysis, analysis of upper, or pharyngeal (PAS-Pharyngeal Airway Space) airways (Nasopharyngeal (NP) and Oropharyngeal (OP) Volumes and Area of Maximal Pharyngeal Constriction (AMPC)) and facial soft-tissue analysis (both in 2D and 3D) were preformed for all patients...Trodimenzionalnost (3D) ljudskog tela proučavana je još od antičkog vremena. Početkom XX veka, gips je bio osnovno dijagnostičko sredstvo za prikazivanje dentofacijalne morfologije, pa je većina ortodonata koristila gipsane studijske modele za analizu denticije i alveolarnih nastavaka u sve tri ravni prostora. Neki ambiciozniji ortodonti, meĎu kojima i Calvin Case predlagali su pravljenje gipsanih modela lica, kako bi se zabeleţile karakteristike lica pre i posle terapije. Kefalometrija, koja je uvedena u ortopediju vilica sredinom dvadesetih godina prošlog veka, omogućila je opisivanje morfologije i rasta kraniofacijalnog skeleta, predviĎanje rasta, planiranje terapije i evaluaciju ishoda terapije. Ipak, potreba za trodimenzionalnom kefalometrijom prepoznata je još sredinom prošlog veka. Kraniofacijalni CBCT skeneri razvijeni su početkom XXI veka kako bi se prevazišla ograničenja konvencionalnih CT skenera. CBCT je omogućio ortodontima da analiziraju skeletne i mekotkivne strukture svojih pacijenata u sve tri dimenzije prostora i kao 3D strukture, i to pomoću samo jednog skena koji pacijenta izlaţe značajno manjoj dozi zračenja u odnosu na CT skener. Cilj ove doktorske disertacije bio je da se procene promene na nivou gornjih vazdušnih puteva i mekih tkiva lica adolescentnih pacijenata tretiranih ekstrakcionom i neekstrakcionom ortodontskom terapijom i odraslih pacijenata tretiranih kombinovanom ortodontsko-hirurškom terapijom. Uzorak se sastojao od 107 pacijenata, izdvojenih iz grupe od 141 pacijenta tretiranog na Stomatološkom fakultetu i u Univerzitetskoj bolnici Case Western Reserve Univerziteta, u Klivlendu, SAD. Svi pacijenti su snimljeni pre i posle terapije prilagoĎenim Hitachi CB MercuRay skenerom (2 mA, 120 kV, 12-inčno polje pregleda u F Modu) u okviru standardnog dijagnostičkog i terapeutskog postupka. U zavisnosti od vrste terapije, pacijenti su podeljeni u tri grupe. Za sve pacijente je uraĎena kefalometrijska analiza, merene su dimenzije gornjih vazdušnih puteva (zapremine nazofarinksa (NP) i orofarinksa (OP) i površina najuţeg dela farinksa (AMPC – Area of Maximal Pharyngeal Constriction) i dimenzije mekih tkiva lica, kako dvodimenzionalne, tako i trodimenzionalne..

A Textbook of Advanced Oral and Maxillofacial Surgery

The scope of OMF surgery has expanded; encompassing treatment of diseases, disorders, defects and injuries of the head, face, jaws and oral cavity. This internationally-recognized specialty is evolving with advancements in technology and instrumentation. Specialists of this discipline treat patients with impacted teeth, facial pain, misaligned jaws, facial trauma, oral cancer, cysts and tumors; they also perform facial cosmetic surgery and place dental implants. The contents of this volume essentially complements the volume 1; with chapters that cover both basic and advanced concepts on complex topics in oral and maxillofacial surgery

STEREOPHOTOGRAMMETRIC ANALYSIS OF THE HUMAN FACE: A TOOL FOR MODERN MORPHOLOGISTS

The introduction of new technologies has provided, in the last years, a significant contribution to anthropometry. In this context, facial anthropometry has greatly benefited from optical instruments such as laser scanners and stereophotogrammetry. The latter technique has proven to be accurate, repeatable and fast; therefore, taking into consideration its non-invasive nature, it has been increasingly applied to medicine, due to the relevant support that anthropometry can provide to this field. A facial anthropometric assessment can provide reliable morphometric details about the presence of deformities and peculiar features connected to underlying pathological conditions, not always easily recognizable. In the case of certain neurologic diseases, it can also provide new insights about the genotype/phenotype correlation taking the close relationship between facial and cerebral development into consideration. Furthermore, the three-dimensional morphometric evaluation of the face can reveal objective parameters useful for the planning and assessment of maxillo-facial and dental treatments, thus facilitating the clinical decisions and increasing the patients\u2019 compliance. The facial morphometric evaluations presented in the current thesis were performed through the VECTRA M3 3D stereophotogrammetric system (Canfield Scientific, Fairfield, NJ, USA). All the patients and control subjects involved were marked with a set of facial landmarks (adapted according to the different study purposes), before the acquisitions. Once the three-dimensional models were obtained, they were elaborated through the software of the stereophotogrammetric system. Data were analysed through different statistical techniques, according to the type of study executed. The morphometric evaluations were divided in two groups: facial morphometric analyses performed through a landmark-based approach and through a surface- based approach. The first group included the studies: 1) \u201cThe face of adult patients affected by Dravet Syndrome: a 3D stereophotogrammetric preliminary assessment\u201d, 2) \u201c3D Craniofacial morphometric analysis of GLUT-1 DS patients\u201d and 3) \u201cStereophotogrammetric analysis of a case of holoprosencephaly\u201d. The second group included the studies: 4) \u201c3D stereophotogrammetric assessment of labial symmetry in a girl treated for a lymphatic malformation\u201d and 5) \u201cFacial reanimation assessment performed through 3D-3D superimposition: a new method\u201d. 7 For both assessed syndromes, study 1 and 2 allowed the individuation of facial features common among the patients, whose recognition can have a role in the diagnosis of the disease, both in children (study 2) and in adult cases (study 1). Study 3 allowed the identification of the presence of dysmorphic facial features in a girl affected by holoprosencephaly with an apparently normal aspect, thus sustaining the potential of the 3D stereophotogrammetric facial analysis in the morphometric characterisation of the face. Study 4 and 5 showed the usefulness of this technique for performing an objective surgical follow-up and final evaluation of maxillo-facial treatments, helping clinicians in their decisions and motivating the patients. In conclusion, all the studies sustained the usefulness, for medical purposes, of an anthropometric assessment of the human face, performed through a three-dimensional stereophotogrammetric analysis. Moreover, they highlighted its applicability to different categories of patients, including children and people with intellectual disability; thus again justifying the increasing diffusion of stereophotogrammetry in clinical and research centres