Biomedical subjects

Graziano Serrao

Publications and source records attributed to Graziano Serrao.

11 recordsLinked to original sources

PubMed2005

Soft tissue facial angles in Down's syndrome subjects: a three-dimensional non-invasive study.

The aim of the present study was to obtain quantitative information concerning the three-dimensional (3D) arrangement of the facial soft tissues of subjects with Down's syndrome. The 3D co-ordinates of 50 soft tissue facial landmarks were recorded by an electromechanical digitizer in 17 male and 11 female subjects with Down's syndrome aged 12-45 years, and in 429 healthy individuals of the same age, ethnicity and gender. From the landmark co-ordinates, geometric calculations were obtained of several 3D facial angles: facial convexity in the horizontal plane (upper facial convexity, mid facial convexity including the nose, and lower facial convexity), mandibular corpus convexity in the horizontal plane, facial convexity including the nose, facial convexity excluding the nose, interlabial angle, nasolabial angle, angle of nasal convexity, left and right soft tissue gonial angles. Data were compared with that collected for the normal subjects by computing the z-scores. Facial convexity in the horizontal plane (both in the upper and mid facial third), facial convexity in the sagittal plane and the angle of nasal convexity were significantly (P < 0.05) increased (flatter) in subjects with Down's syndrome than in the normal controls. Both left and right soft tissue gonial angles were significantly reduced (more acute) in the Down's syndrome subjects. Subjects with Down's syndrome had a more hypoplastic facial middle third with reduced nasal protrusion, and a reduced lower facial third (mandible) than reference, normal subjects.

Adolescent↗

PubMed2004

Nasal dimensions in normal subjects: conventional anthropometry versus computerized anthropometry.

The aim of the current investigation was to compare computerized measurements of nasal linear distances (nasal tip protrusion, height of the cutaneous upper lip, length of the nasal bridge) collected from 705 healthy individuals from Northern Italy (age range 6-60 years) using an electromagnetic digitizer with conventional anthropometric measurements: one set obtained on individuals of central European origin (Zankl et al.), and one set collected from North American Caucasians (Farkas et al.). On average, the present lengths of the nasal bridge were always significantly smaller than the European data (P < 0.01, Student's t for independent samples). Nevertheless, only in one sex and age group of 18 the discrepancy between the two mean values was larger than 10 mm. In other 10 groups, the mean values differed less than 5 mm. More limited differences (up to 6.5 mm) were found in comparison to the American data. For nasal tip protrusion, digital and conventional data were significantly different (up to 4 mm) in 18 instances of 30. On average, the present heights of the cutaneous upper lip were always smaller than the European data (up to 2.9 mm). The differences were statistically significant in 14 groups of 18. Minor discrepancies (less than 1 mm in nine groups of 12) were found in comparison to the American data. Statistical significance was reached only in seven comparisons. In conclusion, the conventional anthropometric and the digital data compared in the current study, though not superimposable, seemed sufficiently interchangeable, at least from a clinical point of view.

Adolescent↗

PubMed2004

Soft-tissue facial areas and volumes in individuals with ectodermal dysplasia: a three-dimensional non invasive assessment.

The objective of this study was to supply quantitative information about the facial soft-tissues of a group of patients with hypohidrotic ectodermal dysplasia. The three-dimensional coordinates of 28 soft-tissue facial landmarks were obtained by an electromagnetic digitizer in 11 male and 9 female patients with hypohidrotic ectodermal dysplasia aged 7-41 years, and in 318 healthy individuals of the same age, ethnicity, and sex. From the landmarks, facial areas (eyes, ears, nose, and lips) and volumes (nose and lips) were calculated according to a geometrical model of face. Data were compared to those collected in the normal subjects by computing z-scores. Male and female z-scores were not significantly different. In the pooled sample, the deviations from the norm were particularly evident in the lips, with a significant (Student's t-test, P < 0.05) increment of the total lip area (mean z-score: 0.96) and of the vermilion area of the upper lip (mean z-score: 1.07), a finding negatively related (r = -0.632) to the number of teeth present in the mouth. The eye area was reduced in most patients, a finding significant on the left side (mean z-score: -0.76). Most of the facial areas and volumes of the ectodermal dysplasia patients had z-scores deviating only +/-2 standard deviations from the reference groups. Only 4% of measurements had z-scores larger than +/-3. Additionally, a large inter-individual variability was found, together with a certain age-related trend of improvement of the number of measurements within the +/-2 interval. The method allowed a simple, low cost, fast, and non invasive examination of the patients, and provided a quantitative assessment of the deviation from the norm.

Adolescent↗

PubMed2003

Growth and aging of facial soft tissues: A computerized three-dimensional mesh diagram analysis.

The normal growth, development, and aging of facial soft tissues was studied by three-dimensional (3D) computerized mesh diagram analysis. The 3D coordinates of 50 soft-tissue landmarks were collected from 591 healthy white northern Italians (351 males, 240 females) 6-40 years of age. For each gender and age class, mean values were computed, and a standardized mesh of equidistant horizontal, vertical, and anterior-posterior lines was constructed. Within each age group, male meshes were superimposed on female meshes. For each gender, the 6-year-old reference mesh was superimposed on the reference mesh of each age group. The global (size plus shape) difference was evaluated by calculating the relevant displacement vectors for each landmark. Consequently, a size normalization was carried out and the shape difference was evaluated by calculating new relevant displacement vectors for each landmark. Growth and development were different along the three spatial planes: the largest increment was observed in the vertical dimension, with major modifications in the soft-tissue profile. The vertical dimension in males increased even after 30 years of age: ear dimensions increased, trichion moved superiorly and posteriorly, and pogonion, menton, and gonion moved anteriorly and inferiorly. In all age groups, size-standardized shape differences were found in the forehead, lower-third facial profile, eyes, cheeks, and ears. In each age class, male dimensions were larger than female dimensions. During childhood, gender differences in size were limited; shape differences were even less manifest. Overall, the profile was more anterior and inferior, the gonia were more inferior and more lateral, the forehead was more anterior, and the ears were larger in males than in females of corresponding age.

Adolescent↗

PubMed2003

Relation between vertical facial morphology and jaw muscle activity in healthy young men.

The aim of the current investigation was to quantitatively analyze the relation between the activity of masticatory muscles and the inclination of the mandibular plane in a group of 73 healthy white men aged 20-36 years. The three-dimensional coordinates of soft-tissue landmarks gnathion and left and right gonion were digitized using an electromagnetic computerized instrument, the orientation of mandibular plane relative to the true vertical was computed and projected on the anatomical sagittal plane. The electromyographic (EMG) potentials of left and right masseter and temporalis anterior during maximum voluntary teeth clenching were recorded, and the mean EMG amplitude calculated. Two groups of men with opposite facial morphology were then selected: all men with a steep mandibular plane (higher than the mean plus one standard deviation) entered a first group (10 'long face' subjects), while all men with a relatively more horizontal mandibular plane (lower than the mean minus one standard deviation) entered a second group (13 'short face' subjects). Mean EMG potentials computed in the two groups were compared by using Student's t -test for independent samples. All the EMG potentials recorded during maximum voluntary clench in the 'long face' men were lower than that recorded in the 'short face' men, with statistically significant differences for all four analyzed muscles (p < 0.05). In conclusion, a non-invasive three-dimensional method confirmed that facial morphology and muscular function are significantly related, at least in men with a sound stomatognathic apparatus.

Adult↗

PubMed2002

Active range of motion of the head and cervical spine: a three-dimensional investigation in healthy young adults.

PURPOSE: To define reference values for head-cervical range of motion (ROM) in healthy young adults, to assess the effect of sex, and to quantify the separate contribution of other body districts. METHODS: Thirty women and 30 men performed maximal head and cervical spine flexion-extension, lateral bending, and axial rotation. Movements were detected using a digital optoelectronic instrument. Maximum head-cervical spine and thoracic motions were separated. RESULTS: Flexion and extension were performed mainly in the sagittal plane. The movement was larger in women (136 degrees) than in men (130 degrees). During flexion, both sexes moved the head-neck and the thorax in the same direction. During extension, men moved only the head-cervical spine, while women moved the two analyzed districts in the opposite directions. Lateral bending was nearly symmetric, associated with head-cervical rotation and extension, and larger in women (91 degrees) than in men (77 degrees). Adjunctive thoracic motion was limited in the sagittal and frontal planes, but larger in the horizontal plane (opposite motions of about 20 degrees). Head-neck rotation was symmetric, and associated with concomitant movements in both the sagittal and frontal planes. It was larger in women (162 degrees) than in men (155 degrees), and performed with limited adjunctive thoracic motions. CONCLUSIONS: The present values can be used as a first group of normative data for head-cervical ROM in young men and women.

Adult↗

PubMed2002

Cephalometric and in vivo measurements of maxillomandibular anteroposterior discrepancies: a preliminary regression study.

One of the aims of the present investigation was to assess three-dimensionally the anteroposterior discrepancy of dental bases using a noninvasive direct procedure. A second aim was to verify the relationship of three-dimensional soft-tissue measurement to the well-established two-dimensional cephalometric assessments of anteroposterior discrepancy. Dental and facial landmarks were directly digitized on 20 orthodontic and maxillofacial surgery patients aged 8 to 26 years using an electromagnetic three-dimensional computerized digitizer. The anteroposterior maxillomandibular discrepancy was measured by calculating the linear distances between the projections of subnasal and sublabial landmarks on the occlusal plane, subnasal and sublabial landmarks on Camper's plane, and insertion of maxillary and mandibular median labial frenula on the occlusal plane. From lateral cephalograms of the same patients, the following measurements were obtained: subspinale point-nasion-supramentale point (ANB) angle; corrected ANB angle that compensates for the position of the maxilla and rotation of the mandible relative to the cranial base; Wits appraisal; MM-Wits, linear distance between the projections of points A and B on the bisector of the palatal plane to mandibular plane angle; and soft-tissue Wits, linear distance between the projections of soft-tissue points A and B on the bisecting occlusal plane. The best two-dimensional vs three-dimensional linear regression (r = 0.91) was found between Wits appraisal and the linear distances between the projections of maxillary and mandibular median labial frenula on the occlusal plane (Wits = -1.05 x 3D measurement - 3.75). The three-dimensional evaluation of the sagittal discrepancy of the jaws directly performed in vivo may allow a more complete analysis of a patient's soft-tissue drape together with the underlying hard-tissue structure.

Adolescent↗

PubMed2002

Three-dimensional assessment of the reliability of a postural face-bow transfer.

STATEMENT OF PROBLEM: Incorrect 3-dimensional orientation of a dental cast may compromise the functional and esthetic result of prosthetic restorations. PURPOSE: This study assessed the reliability of a new method to transfer the 3-dimensional orientation of the occlusal plane with a postural face-bow. MATERIAL AND METHODS: The 3-dimensional position of the occlusal plane in 20 subjects (age 20 to 32 years) with a complete dentition in both arches was assessed with a postural face-bow. An irreversible hydrocolloid impression of the maxillary arch was made for each subject and poured in dental stone. The maxillary arch was mounted in an articulator with use of a postural face-bow. The 3-dimensional position of the occlusal plane was then measured and compared to the values obtained with the use of a previously certified, computerized, noninvasive instrument. This instrument digitizes the coordinates of dental and facial landmarks and then calculates the spatial position of the occlusal plane. For each subject, the direct assessment and the face-bow measurement were compared by calculating the absolute difference of the following: the inclination of the occlusal plane relative to the true vertical, frontal plane projection (angle alpha) and sagittal plane projection (angle beta); intercondylar distance; distance of the center of gravity of the anterior part of the maxillary arch to the midpoint of the intercondylar axis; and the maxillary right canine to right condylion distance. Descriptive statistics of the differences were calculated. RESULTS: The postural face-bow appeared reliable and compared well to the computerized assessment, with mean differences ranging from 2.5 degrees to 3 degrees. CONCLUSION: In the population tested, a postural face-bow reliably reproduced the spatial orientation of the occlusal plane relative to the true horizontal plane. This position was transferred to an articulator with limited errors.

Adult↗

PubMed2002

Relationship between the number of occlusal contacts and masticatory muscle activity in healthy young adults.

The electromyographic (EMG) potentials of left and right masseter and temporalis anterior muscles were recorded in 23 healthy young adults during: 1. a 3-second maximum voluntary clench (MVC) on cotton rolls positioned on the posterior teeth (standardized recording); and 2. a 3-second MVC in intercuspal position. EMG potentials recorded in intercuspal position were standardized as a percentage of the mean potentials of the standardized recording, and the EMG muscle activity was calculated. The number of occlusal contacts in intercuspal position was assessed by using eight microm thick shim stocks. Two groups of subjects with either 1. Less than ten occlusal contacts (11 subjects with "few contacts"); or 2. At least ten occlusal contacts (12 subjects with "many contacts") were selected. The MVC muscle activity in the "few contacts" group was significantly lower than that recorded in the "many contacts" group (p<0.005). In conclusion, the number of occlusal contacts and masticatory muscular function are significantly related, at least in young adults with a sound stomatognathic apparatus.

Adult↗

PubMed2002

Elliptic Fourier analysis of facial profiles during growth and development.

The quantitative analysis of facial soft tissues is of overwhelming importance for orthodontic patients. To assess the normal age-related variations in shape, soft tissue facial profiles were studied in 96 healthy male children 3 to 11 years of age and 16 young men (age 18). Standardized left-side photographs were taken of each subject, and facial profiles were traced between trichion and cervical point. The line joining the 2 landmarks was set as the baseline, and each outline was automatically digitized and mathematically reconstructed by a 30-harmonic elliptic Fourier series expansion. The same soft tissue profile was traced and digitized from the Bolton standards of comparable age. All profiles were standardized to the same area, and shape modifications were quantified by calculating the morphologic distance between the Fourier reconstructions of each facial profile and of (1) the 18-year-old Bolton standard (MD-18) and (2) the age-related Bolton standard. Descriptive statistics were computed for each age class. On average, MD-18 was 7.23 at 3 years of age, increased between 6 and 9 years of age, and decreased hereafter, reaching 6.86 at 18 years of age. Within-group variability peaked at 8 years of age, and was minimal at 6 and 18 years of age. The current soft tissue child profiles seemed different from the profile obtained from the Bolton standards.

Adolescent↗

PubMed2000

A direct in vivo measurement of the three-dimensional orientation of the occlusal plane and of the sagittal discrepancy of the jaws.

The aim of the present investigation was to three dimensionally assess craniofacial relationships in vivo. Specifically, by using a non-invasive direct technique, the following measurements were made: 1) natural head position relative to the ground; 2) orientation of the occlusal plane relative to the subject's intrinsic facial planes; and 3) anteroposterior discrepancy of the dental bases, taking into consideration all the facial hard- and soft-tissue structures. Several dental and soft-tissue facial landmarks were directly digitized from 24 adult healthy volunteers with Angle Class I occlusions by means of an electromagnetic three-dimensional computerized digitizer. In natural head position, the three-dimensional orientation of Camper's, occlusal, and mandibular planes were measured along with the anteroposterior maxillo-mandibular discrepancies. In the frontal plane projection, all the measured planes appeared about horizontal. In the lateral plane projection, on average, Camper's plane deviated from the true horizontal by approximately 18 degrees (in a 'head flexed' direction). The occlusal plane deviated from the same horizontal by about 14 degrees, while the mandibular plane had a steeper inclination (about 30 degrees ); both planes were significantly correlated to Camper's plane. The measurements of anteroposterior jaw discrepancy revealed a wide range of sagittal relationships in the analyzed subjects. The method was found to be repeatable and fast. This direct three-dimensional in vivo assessment of the orientation of occlusal plane relative to the other facial planes could allow for a more comprehensive analysis of maxillo-mandibular sagittal discrepancies.

Journal Article↗