Can Volumetric and Morphological Variants of Sphenoid Sinuses Influence Sinuses Opacification?

Improvements in computed tomography and in functional endoscopic sinus surgery have recently increased interest toward paranasal sinus anatomy and anatomic variations that can be observed in patients affected by sinusitis. Isolated sphenoid sinusitis is a relatively rare pathology, often related to nonspecific symptoms, therefore making diagnosis difficult. The correlation between this type of sinusitis and anatomical variants remains unclear.The authors' aim was to retrospectively revise paranasal sinuses computed tomography scans of patients affected by sphenoid sinusitis, compared with a control group, analyzing the types of sphenoid sinus and the presence of aberrant pneumatization, and performing a segmentation of the sphenoid sinuses to calculate the volumes.Sphenoid sinuses of 60 patients affected by sinus opacification, compared with a control group, were segmented. Type of sinus (sellar, presellar, postsellar) and presence of aberrant pneumatization were assessed as well. Possible statistically significant differences in volumes according to sex and group were assessed through 2-way ANOVA test (P < 0.05). Post-hoc test was assessed through Student t test. χ test was applied in order to verify the statistically significance of differences in frequency of different types of sinus pneumatization variants (P < 0.05).Average volume of sphenoid sinuses in males was of 7.672 cm and of 7.751 cm in females within the group of patients; statistically significant differences in volume were found according to sex (P: 0.342), but not between the patients and control group (P: 0.0929). Post-hoc test verified that males affected by sinus opacification showed smaller volumes in comparison with the control males (P < 0.05). In addition, patients by affected sinus opacification showed more frequently the postsellar type and were less affected by pneumatization variants of the sphenoid bone than the control group (P < 0.05).This study first suggests the possible protective role of variants of pneumatization in the development of sphenoid sinus opacification.

Anatomical Uniqueness of Ear Morphology: A Novel Metrical Approach through Three-Dimensional Superimposition.

Uniqueness of ear morphology has been a widely debated issue in cephaloscopy, but past studies used only two-dimensional approaches. In the current investigation, the right and left ears of 10 healthy adults were imaged twice by stereophotogrammetry at the interval of a few seconds. The ear images obtained from the two acquisitions were superimposed both within subject (group of matches) and among subjects (group of mismatches). A point-to-point root mean square distance was calculated between the two three-dimensional models. Differences according to side and group were assessed by two-way analysis of variance. In total, 200 superimpositions were performed. On average, the point-to-point root mean square distance was 0.31 mm in cases of matches and 1.43 mm in cases of mismatches: differences were statistically significant (p < 0.01). Results provided quantitative data for the assessment of uniqueness of ear morphology, highlighting differences based on their three-dimensional morphology.

Application of 3D models of palatal rugae to personal identification: hints at identification from 3D-3D superimposition techniques.

Palatal rugae are known in literature as individualizing anatomical structures with a strong potential for personal identification. However, a 3D assessment of their uniqueness has not yet been performed. The present study aims at verifying the uniqueness of 3D models of the palate. Twenty-six subjects were recruited among the orthodontic patients of a private dental office; from every patient, at least two dental casts were taken in different time periods, for a total of 62 casts. Dental casts were digitized by a 3D laser scanner (iSeries, Dental Wings©, Montreal, Canada). The palatal area was identified, and a series of 250 superimpositions was then performed automatically through VAM©software in order to reach the minimum point-to point distance between two models. In 36 matches the models belonged to the same individual, whereas in 214 mismatches they came from different subjects. The RMS (root mean square) of point-to-point distances was then calculated by 3D software. Possible statistically significant differences were assessed through Mann-Whitney test (p < 0.05). Results showed a statistically significant difference in RMS mean point-to-point distance between matches (mean 0.26 mm; SD 0.12) and mismatches (mean 1.30; SD 0.44) (p < 0.0001).All matches reached an RMS value below 0.50 mm. This study first provided an assessment of uniqueness of palatal rugae, based on their anatomical 3D conformations, with consequent applications to personal identification.

Age-related and sex-related changes in the normal soft tissue profile of native Northern Sudanese subjects: a cross-sectional study.

Information about age-related and sex-related normative measurements of the nasolabial region in native Northern Sudanese subjects is scanty. We have therefore used a hand-held laser scanner to measure nasolabial angles and distances, and collected the 3-dimensional coordinates of seven landmarks on the facial soft tissues from 654 healthy native Northern Sudanese subjects (327 male and 327 female, aged 4-30 years). From these we calculated five angles and two linear distances and took the mean (SD) for age and sex, and compared them using factorial analysis of variance. All measurements analysed were significantly modified by age in both sexes (p < 0.01) except for the distance from the lower lip to Ricketts' E-line. Sex had a significant effect on the mentolabial and maxillary prominence angles and both distances (p < 0.005). Nasal convexity and the interlabial angle became more obtuse with growth, while the nasolabial and mentolabial angles reduced progressively with female subjects having significantly more obtuse mentolabial angles (p < 0.001). The maxillary prominence angle progressively decreased during childhood, and increased after adolescence, with larger values in male subjects. The upper and lower lip distances from Ricketts' E-line were also significantly larger in male subjects (p < 0.003), but the difference reduced with age. Overall, there were several differences when we compared our data with published data for African and white subjects, which points to the need for ethnic-specific data. Measurements collected in the current study could be used for the quantitative description of facial morphology in native Northern Sudanese children, adolescents, and young adults.

Comparison of soft-tissue orbital morphometry in attractive and normal Italian subjects.

OBJECTIVE: To identify esthetic characteristics of the orbital soft tissues of attractive Italian adult women and men. MATERIALS AND METHODS: Three-dimensional computerized digitizers were used to collect the coordinates of facial landmarks in 199 healthy, normal subjects aged 18 to 30 years (71 women, 128 men; mean age, 22 years) and in 126 coetaneous attractive subjects (92 women, 34 men; mean age, 20 years) selected during beauty competitions. From the landmarks, six linear distances, two ratios, six angles, and two areas were calculated. Attractive subjects were compared with normal ones by computing z-scores. RESULTS: Intercanthal width was reduced while eye fissure lengths were increased in both genders. Orbital heights (os-or) were increased only in attractive women, with a significant gender-related difference. The inclinations of the eye fissure were increased in attractive subjects, while the inclinations of the orbit were reduced. For several of the analyzed measurements, similar patterns of z-scores were observed for attractive men and women (r  =  .883). CONCLUSION: Attractive women and men had several specific esthetic characteristics in their orbital soft tissues; esthetic reference values can be used to determine optimal goals in surgical treatment.

Facial soft-tissue volumes in adult Northern Sudanese individuals with Down syndrome.

OBJECTIVE: To investigate dimensions and ratios of soft-tissue facial volumes of adult Northern Sudanese subjects with Down syndrome by using computerized anthropometric measurements. DESIGN, SETTING, AND PATIENTS: The 3D coordinates of soft-tissue facial landmarks were obtained by a computerized digitizer in 26 Northern Sudanese adult subjects with Down syndrome (18 men, 8 women, aged 17-34 years), and in 99 healthy Northern Sudanese controls (48 women, 51 men) of the same age range. From the landmarks, several facial volumes and volume ratios were calculated. Data were compared to those collected in healthy individuals by computing z-scores. RESULTS: In subjects with Down syndrome, facial volumes were significantly smaller than in control subjects (Student's t, p < 0.05). The patterns of deviation from the norm were similar in men and women. When compared to controls, subjects with Down syndrome had no differences in nose volume as a fraction of total facial volume and a larger total lip volume as a fraction of total facial volume; within the facial middle third, they had relatively larger upper lip volumes and relatively smaller nose volumes. CONCLUSIONS: The facial soft-tissue structures of subjects with Down syndrome differed from those of normal controls of the same age, sex and ethnic group: a reduced facial size was coupled with specific variations in the nasal and labial regions.

The labial aging process: a surface analysis-based three-dimensional evaluation.

BACKGROUND: With increasing age, the smile becomes elongated and less appealing. Currently, several methods are proposed for analysis of lip morphology including lateral cephalograms, profile and frontal photographs, video images, and three-dimensional systems. Despite several descriptions of morphologic and histologic age-related changes in the literature, no scientific well-supported model of the labial aging process is reported. METHODS: For this study, 33 healthy volunteers were selected and divided into two groups according to age: a youthful group (ages 21-34 years) and an aged group (ages 45-65 years). Their dental and labial stone casts were obtained, digitized, and virtually reproduced using a computerized electromechanical digitizer and applying nonuniform rational B-spline geometry. To obtain a synthetic parameter describing local surface deformation, average curvature and curvature variability indexes were computed and compared. RESULTS: No significant age- or sex-related differences in the average curvature were detected. In contrast, the curvature variability was significantly greater in the young than in the aged subjects. CONCLUSIONS: The labial arch surface remains macroscopically constant between the third and the sixth decades of life, but with local modifications that influence the standard deviation of its curvature. A high standard deviation described the protruding labial appearance of the young subjects, whereas a reduced one described the flat lips of the aged subjects. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Morphometry of the soft tissues of the orbital region in Northern Sudanese persons.

The orbital region plays a predominant role in the evaluation of the craniofacial complex. No current normative data exist for Northern Sudanese subjects. In the current study information about normal sex- and age-related dimensions of the orbital region was provided. The three-dimensional coordinates of ten landmarks on the orbital soft tissues were obtained using a hand-held laser scanner in 654 healthy Northern Sudanese subjects aged 4-30 years. From the landmarks, biocular and intercanthal widths, paired height and inclination of the orbit relative to both the true horizontal (head in natural head position) and Frankfurt plane, length and inclination of the eye fissure, the relevant ratios, were calculated, and averaged for age and sex. Comparisons were performed by factorial analysis of variance. All analysed linear soft-tissue orbital dimensions, except intercanthal width and left orbital height, were significantly larger in men than in women (p<0.01). A significant sexual dimorphism was found also for the height-to-width ratios (larger in women in most age groups), the orbital inclinations vs. the true horizontal and Frankfurt plane (both measurements were almost always larger in men than in women), and the right side inclination of the eye fissure vs. the true horizontal (larger in women than in men), while no sex-related differences were observed for the left side inclination of the eye fissure vs. the true horizontal. All measurements but the right side inclination of the eye fissure vs. the true horizontal underwent significant modifications as a function of age, with several significant age×sex interactions. Biocular and intercanthal widths, orbital height, length of the eye fissure, all increased from childhood to young adulthood; in the second decade of life all age-related increments were larger in men than in women. Overall, when compared to literature data for African and Caucasoid subjects, several differences were found, pointing to the necessity of ethnic-specific data. Data collected in the present investigation could serve as a database for the quantitative description of human orbital morphology during normal growth and development. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, ageing of living and dead people, personal identification) may also benefit from age- and sex-based data banks.

The role of the golden proportion in the evaluation of facial esthetics.

OBJECTIVE: To demonstrate if one or more golden relationships between different measurements of the human face exist. MATERIALS AND METHODS: To make our measurements, we used three-dimensional (3D) stereophotogrammetry, which has proved to be the "gold standard" in the field of facial anthropometry. We obtained 3D stereophotogrammetric facial acquisitions of 400 healthy young adult subjects, then had them scored by an Evaluation Jury. Each subject received an esthetic evaluation ranging from 0 to 40. Individuals with a score larger than 28 were considered very attractive (VA), and individuals with a score lower than 12 were considered not attractive (NA). Fifteen subjects per group were chosen by chance, with a final total group of 60 subjects: 15 VA males, 15 NA males, 15 VA females, and 15 NA females. For each subject, a set of facial distances was obtained from the stereophotogrammetric facial reconstruction, and 10 ratios were computed. The effects of sex and attractiveness were tested by analysis of variance. Additionally, Student's t-tests verified if the ratios were statistically different from the golden ratio. RESULTS: For nine ratios, no significant effects of sex or attractiveness were found. Only the eye-mouth distance/height of the mandible ratio was significantly influenced by sex (P = .035) and attractiveness (P = .032). Seven out of 10 ratios were statistically different from the hypothetical value of 1.618, and only three of them were similar to the golden ratio. CONCLUSIONS: Ratios between 3D facial distances were not related to attractiveness. Most of the facial ratios were different from the golden ratio.

Soft tissue facial morphometry before and after total oral rehabilitation with implant-supported prostheses.

The objective of the current study was to assess a low-cost, noninvasive facial morphometric digitizer to assist the practitioner in three-dimensional soft-tissue changes before and after oral rehabilitation. Twenty-two patients aged 45 to 82 years, all with edentulous maxilla and mandible, were assessed both before and after receiving their definitive complete implant-supported prostheses (each received 4-11 implants in each dental arch; full-arch fixed prostheses were made). The three-dimensional coordinates of 50 soft-tissue facial landmarks were collected with a noninvasive digitizer; labial and facial areas, volumes, angles, and distances were compared without and with the prostheses. Dental prostheses induced significant reductions in the nasolabial, mentolabial, and interlabial angles, with increased labial prominence (P < 0.05, Wilcoxon test). Lip vermilion area and volume significantly increased; significant increments were found in the vertical and anteroposterior labial dimensions. The presence of the dental prostheses significantly (P < 0.001) modified the three-dimensional positions of several soft-tissue facial landmarks. In conclusion, the current approach enabled quantitative evaluation of the final soft-tissue results of oral rehabilitation with implant-supported prostheses, without submitting the patients to invasive procedures. The method could assess the three-dimensional appearance of the facial soft tissues of the patient while planning the provisional prosthetic restoration, providing quantitative information to prepare the best definitive prosthesis.

The occlusal plane in the facial context: inter-operator repeatability of a new three-dimensional method.

The repeatability of a non-invasive digital protocol proposed to evaluate the three-dimensional (3D) position of the occlusal plane in the face is assessed. Dental virtual models and soft tissue facial morphology of 20 adult subjects were digitally integrated using a 3D stereophotogrammetric imaging system. The digital 3D coordinates of facial and dental landmarks were obtained by two different operators. Camper's (facial) and occlusal (dental) planes were individuated, and their 3D relationships were measured. The repeatability of the protocol was investigated and showed no significant differences in repeated digitizations. The angle between occlusal and Camper's planes was smaller than 2° in the frontal and horizontal projections. In the sagittal projection, the angle was observed to be, on average, 4.9°. The determined occlusal plane pitch, roll and yaw values show good agreement with previously published data obtained by different protocols. The current non-invasive method was repeatable, without inter-operator differences and can facilitate assessment of healthy subjects.

Facial movement before and after masseteric-facial nerves anastomosis: a three-dimensional optoelectronic pilot study.

To quantify the effects of facial palsy reanimation, 14 patients aged 17-66 years were analysed. All patients had unilateral facial paralysis, and were candidates for surgical masseteric to facial nerve anastomosis. Two patient groups were measured: seven patients were waiting for surgery, the other seven patients had already been submitted to surgery, and had regained facial mimicry. Each patient performed three facial animations: brow raise; free smile; lip purse. These were recorded using an optoelectronic motion analyser. The three-dimensional coordinates of facial landmarks were obtained, their movements were computed, and asymmetry indices calculated (differential movements between the two hemi-faces: healthy and paretic/rehabilitated). Before surgery, mobility was larger in the healthy than in the paretic side; after surgery, the differences were reduced (brow raise and lip purse), or even reversed (smile). Before surgery, lip purse was performed with significant labial asymmetry (p=0.042; larger healthy side movement). After surgery, asymmetry indices reduced. Total labial asymmetry during smiling was significantly different from 0 before surgery (p=0.018, larger healthy side movement). After surgery, all asymmetry indices became non-significant. Before surgery the lateral displacements of all labial landmarks were towards the healthy side, while they normalized after surgery.

Morphometry of the ear in north Sudanese subjects with Down syndrome: a three-dimensional computerized assessment.

Down syndrome (DS) is the most frequent live-born autosomal aneuploidy in humans. Scanty data on the craniofacial phenotype of African subjects with DS have been published so far. We wanted to detail the morphologic characteristics of the ears in north Sudanese subjects with DS. The three-dimensional coordinates of 13 soft-tissue landmarks on the ears were obtained using a laser scanner in 64 north Sudanese subjects with DS aged 4 to 34 years and in 682 sex- and age-matched control subjects. From the landmarks, left and right linear distances (ear width and length), ratios (ear width-to-ear length), areas (ear area), angles (angle of the auricle vs the facial midplane), and the three-dimensional symmetry index were calculated. Distances, angles, areas, and ratios were computed. Subject and reference data were compared by computing z scores and calculating Student t tests. Ear width, length, and area were significantly (Student t test, P < 0.001) smaller in the subjects with DS than in the reference subjects. On the right side of the face, the subjects with DS had larger ear width-to-ear length ratios and larger angles of the auricle versus the facial midplane than the reference subjects. The three-dimensional symmetry index was significantly larger in the reference subjects. In conclusion, ear dimensions, position, and shape significantly differed in subjects with DS when compared with sex-, age-, and ethnic group-matched control subjects.

Three-dimensional assessment of nose and lip morphology in North Sudanese subjects with Down syndrome.

OBJECTIVE: To detail the nasolabial morphologic characteristics of North Sudanese subjects with Down syndrome (DS). MATERIALS AND METHODS: Nasolabial morphology was assessed three-dimensionally in 64 North Sudanese subjects with DS aged 4 to 34 years and in 682 sex- and age-matched controls. Three-dimensional facial coordinates were collected using a laser scan, and selected distances, angles, areas, and volumes were computed. Subject and reference data were compared by computing z-scores and Student's t-tests. RESULTS: The nose was significantly smaller (area) in subjects with DS than in reference subjects, and it had a different shape (more flat angle of alar slope, more acute nasal tip angle). The vertical (nasal bridge length, nose height) and anteroposterior (nasal tip protrusion) dimensions were reduced, while the horizontal dimensions (alar base width, inferior widths of the nostrils) were increased. The nasolabial angle was increased. The cutaneous lip volume was significantly smaller, while the vermilion lip area was larger in the subjects with DS. The mouth and philtrum widths were significantly reduced, while the vermilion height was significantly increased. CONCLUSION: Analyzed subjects with DS had a hypoplastic nose and different upper and lower lips than did reference, normal subjects.

Age- and sex-related changes in the normal human external nose.

The objective of this study was to measure: (1) normal sex-related dimensions of external nose (linear distances, ratios, angles, volume and surface area); and (2) growth changes between childhood and old age. The three-dimensional coordinates of several soft-tissue landmarks on the external nose were obtained by a non-invasive, computerized digitizer in 519 male and 340 female healthy subjects aged 4-73 years. The subjects were divided into 11 non-overlapping age groups: for children and preadolescent subjects, 2-year spans were used, while larger intervals were used for adolescent and adult subjects. From the landmarks, nasal volume and external surface area; nasal and alar base widths, nasal height, nasal bridge length, philtrum length, nasal tip protrusion, right and left nostril lengths, superior and inferior nostril widths; nasal tip protrusion-to-nasal height, and nasal width-to-nasal height ratios; nasal convexity, alar slope, and nasal tip angles were calculated, and averaged for age and sex. Comparisons were performed by factorial analysis of variance. On average, men had larger nasal external volume and area, linear distances and nasal width-to-height ratio than women (p<0.01); no sex differences were found for the angles and the nasal tip protrusion-to-nasal height ratio. Age significantly influenced all analyzed measurements (p<0.001): nasal volume, area, linear distances increased from childhood to old age, while the nasal tip angle decreased as a function of age. No consistent age related patterns were found for the ratios and the nasal convexity and alar slope angles. Men and women had different age related patterns, with significant sex by age interactions (p<0.001). Overall, in most occasions male increments in nasal dimensions were larger than female ones. Data collected in the present investigation could serve as a database for the quantitative description of human nasal morphology during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age and sex based data banks.

Three-dimensional analysis of facial morphology: growth, development and aging of the orolabial region.

Soft tissue analysis plays an increasing, strategic role in the recognition of facial alterations, but there are scanty three-dimensional reference data during normal growth, development and aging. In the current study, 532 male and 386 female healthy subjects aged 4 to 73 years were analyzed using a non-invasive, computerized electromagnetic digitizer, and normal dimensions of mouth and lips were obtained in the three-dimensional space. Labial thickness and curvature were also assessed in a selected group of 40 men and women, equally divided into young (age 21-30 yr, mean 25 yr) and old persons (age 45-65 yr, mean 55 yr). Lip vermilion area to volume, and vermilion height to cutaneous lip height ratios decreased with age in both sexes. On average, the lips were thicker in men and in young persons than in women and in old persons. Mean labial curvature was larger in young men than in the other groups, and it was more variable in young than in old persons. Data collected in the present investigation can be used as a data base for the quantitative description of human lip morphology during normal growth, development and aging.

Digital dental cast placement in 3-dimensional, full-face reconstruction: a technical evaluation.

INTRODUCTION: Several noninvasive methods are used for 3-dimensional (3D) morphologic facial and dental analysis to aid practitioners during diagnosis and treatment planning. Integrating dental and facial noninvasive 3D reproduction could improve the efficacy of treatment management. METHODS: Dental virtual model and soft-tissue facial morphology were digitally integrated from 11 adults with a 3D stereophotogrammetric imaging system (Vectra, Canfield Scientific, Fairfield, NJ). The digital 3D coordinates of 3 facial landmarks (N, nasion; Ftr, frontotemporale right; Ftl, frontotemporale left) and 3 dental landmarks (I, interincisor; Pr, PI, tips of the mesiovestibular cusps of the right and left first permanent premolars) were then obtained by using Vectra's software. Additionally, the coordinates of the same 6 landmarks were digitized directly on each subject by using a 3D computerized electromagnetic digitizer (in vivo). Seven linear measurements were made between the occlusal plane (Pr-I-Pl) and the facial landmarks (Ftr-N-Ftl). The accuracy and reliability of the reconstruction were tested by in-vivo measurements and repeated acquisitions. RESULTS: The greatest mean relative error of measurements was smaller than 1.2%. No significant differences in repeatable reproductions were found. CONCLUSIONS: Integration of facial stereophotogrammetry acquisition and dental laser scan reproduction is possible with marginal error.

Accuracy and reproducibility of a 3-dimensional stereophotogrammetric imaging system.

PURPOSE: To test the accuracy and reproducibility of a 3-dimensional (3D) stereophotogrammetric imaging system for measuring the facial soft tissues of healthy subjects. MATERIALS AND METHODS: Three-dimensional soft tissue facial landmarks were obtained from the faces of 10 adult subjects, by use of a 3D stereophotogrammetric imaging system (Vectra; Canfield Scientific, Fairfield, NJ). Sixteen linear measurements were computed. Systematic and random errors between operators, calibration steps, and acquisitions were calculated. RESULTS: No systematic errors were found for all performed tests (P > .05, paired t test). The method was repeatable, and random errors were always lower than 1 mm, except for the distance from cheilion to cheilion. Repeated sets of acquisition showed random errors up to 0.91 mm, without systematic biases. CONCLUSION: The 3D stereophotogrammetric imaging system can assess the coordinates of facial landmarks with good precision and reproducibility. The method is fast and can obtain facial measurements with few errors.

Age- and sex-related changes in three-dimensional lip morphology.

The objective of this study was to supply information about: (1) normal sex-related dimensions of mouth and lips (linear distances, ratios, angles, area, volume); and (2) growth changes between childhood and old age. The three-dimensional coordinates of several soft-tissue landmarks on the lips and face were obtained by a non-invasive, computerized electromagnetic digitizer in 532 male and 386 female healthy subjects aged 4-73 years. From the landmarks, linear distances (mouth width, width of the philtrum, vermilion heights of the upper, lower and total lips, total lip height), the vermilion height-to-mouth width ratio, areas (vermilion of the upper, lower and total lip) and volumes (upper, lower, and total lip volume) were calculated and averaged for age and sex. Comparisons were performed by factorial analysis of variance. Mouth width, width of the philtrum, total lip height, and lip volumes were significantly larger in men than in women (p<0.01), increased with age (p<0.001), and had age x sex interactions (p<0.001). Vermilion areas and heights of the lower and total lips progressively increased with age until late adolescence, and then decreased with aging (p<0.001). The vermilion height-to-mouth width ratio was larger in women than in men (p<0.001), and decreased with age (p<0.001). Data collected in the present investigation could serve as a database for the quantitative description of human lip morphology during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age- and sex-based data banks.