Standardized Digital Photographs Research Articles

Factors affecting the rate of oxidation and resultant discolouration of tetracyclines contained in endodontic medicaments and irrigants.

To determine the effect of pH, oxygen levels and ions on tetracycline oxidation and resultant discolouration. Solutions of demeclocycline hydrochloride or doxycycline hyclate were prepared and exposed to different pH conditions, pure oxygen or carbon dioxide, ascorbic acid or various ions (from calcium chloride, calcium nitrate, strontium chloride, magnesium chloride, zinc chloride, and bismuth nitrate). Subsequently, they were exposed to intense visible blue light (470±15nm) for 24h. Colour change was monitored using standardized digital photography. Parametric statistical analysis employing the Wilcoxon matched-pairs signed-rank test was performed to compare the mean change in different colour channels, assessing the discolouration effect of the modified conditions. An acidic pH reduced discolouration, whilst alkaline pH increased it. A higher oxygen tension resulted in more discolouration, as did the presence of calcium, strontium, and bismuth ions, all of which bind to tetracyclines. Conversely, zinc and magnesium ions had a mild photoprotective effect. Ascorbic acid, an anti-oxidant, reduced the level of discolouration. The tendency of these tetracyclines to undergo photo-oxidation is increased by common variables present in the clinical environment. There are potential benefits from using photoprotectors and anti-oxidants in these materials, to reduce the possibility of discolouration.

Effects of alcohol and/or tobacco exposure on spontaneous alveolar bone loss in rat.

The aim of the present study was to evaluate the effect of alcohol and/or tobacco exposure on spontaneous alveolar bone loss in Wistar rats. Twenty-four, male, 60 day-old, Wistar rats were assigned to 4 groups: Group 1 received 10 mL/kg of glucose solution (5%). Group 2 received 2 g/kg alcohol (20%). Group 3 was exposed to tobacco smoke (6 cigarettes/60 min). Group 4 received both interventions of groups 2 and 3. Alcohol was given by gastric gavage and cigarette exposure was performed using a forced ventilation chamber. After 30 days, animals were sacrificed and the upper maxillae removed and defleshed. Morphometric analysis of alveolar bone loss (ABL) around the second molar was performed in standardized digital photographs. Statistical analysis was conducted using paired t-test, one-way ANOVA and occurrence of spontaneous periodontal disease (ABL ≥ 0.39 mm) was analyzed by Fisher's exact test. Significant differences in body weight were observed between all groups. Group 2 presented higher body weight as compared to the 3 other groups at 4 weeks (p≤0.05). Mean ABL values were 0.31 mm (±0.08), 0.29 mm (±0.07), 0.33 mm (±0.10), and 0.33 mm (±0.08) for groups 1, 2, 3, and 4, respectively. No significant differences were found among groups. In the analysis of occurrence of periodontal breakdown, alcohol exposure decreased the occurrence of ABL and cigarette exposure increased ABL. The combination of alcohol and cigarette exposure did not differ from the control group. Alcohol consumption decreased the occurrence of periodontal breakdown, while tobacco increased this rate.

Cranial shape, size and cervical motion in normal newborns

BackgroundDeformational plagiocephaly (DP) and torticollis are commonly seen in infants and they often co-occur, but little is known of the prevalence and relationship of these conditions in the immediate newborn period. No previous studies focusing on the relationship between cranial shape and cervical motion in newborns can be found. ObjectivesDetermining the incidence rates and characteristics of DP and torticollis and examining the relationship between cervical range of motion (ROM), cranial size and cranial shape in neonates. MethodsA single-center, descriptive cross-sectional study including 155 healthy neonates was conducted. Participants were examined during their birth hospitalization. Oblique Cranial Length Ratio (OCLR) and Cephalic Index (CI), indicating cranial asymmetry and shape, were measured from standardized digital photographs with a computer-based cephalometric method. Cervical ROM was measured with goniometry. Results7.7% of the newborns had DP and 3.9% had torticollis. 46.4% presented lesser cervical imbalances. DP was associated with gestational diabetes (adjusted OR 5.6; p<0.01) and vacuum assisted delivery (adjusted OR 6.8; p<0.01), but not at all with torticollis. CI correlated strongly with cervical ROM in all directions, while no definite association between cranial asymmetry and cervical motion could be found. ConclusionsDP and torticollis are common and minor cervical imbalances very common in normal newborns. Our results support the theory that in most cases neither DP nor torticollis is congenital, but rather develops and worsens synergistically in early infancy. Still, although no direct association between DP and torticollis was found, cranial shape is linked to cervical motion at birth.

Determination of canal orifice co-ordinates and MB2 incidence of maxillary first molars in a Turkish sub-population

Objectives. To measure the co-ordinates of the root canal orifices and to determine the incidence of mesiobuccal-2 (MB2) in maxillary first molars in a Turkish sub-population. Materials and methods. Standard digital photographs were taken under a stereomicroscope from the occlusal aspect of each tooth (n = 176) before and after crown removal. Canal orifices were negotiated under moderate magnification using dental loupes. The coordinates of the orifices and the distances of each from the central fossa were measured by using geographic software. Intensity maps of the orifice locations were created by using the co-ordinates of all canal orifices. A representative map was drawn using the mean values of orifice locations and access projection area. Results. In the right maxillary first molars, the mean values for the (X, Y) co-ordinates were (0.67, 2.68) for mesiobuccal-1 (MB1), (0.81, 0.84) for MB2, (−1.12, 1.26) for distobuccal-1 (D1), (−0.89, 0.23) for distobuccal-2 (D2) and (0, −2.50) for palatinal (P); the corresponding mean values in the left maxillary first molars were (−0.78, 2.56), (−0.98, 0.90), (0.99, 1.18), (0.69, 0.78) and (0.00, −2.53), respectively. The average MB1–MB2 distance was 1.97 mm. Distobuccalcanal orifices were localized at the distal side of the center in 98.3% of teeth. The incidence of MB2 was 46.02%. Conclusions. The distobuccal canal orifice is mostly located on the distal side of the central fossa. Thus, it should be considered that the access cavity of the maxillary molars may not be always limited mesially. The incidence of MB2 in this sub-population was 46.02%, which is of great importance clinically.

Technical Note: 3D From Standard Digital Photography of Human Crania—A Preliminary Assessment

This study assessed three-dimensional (3D) photogrammetry as a tool for capturing and quantifying human skull morphology. While virtual reconstruction with 3D surface scanning technology has become an accepted part of the paleoanthropologist's tool kit, recent advances in 3D photogrammetry make it a potential alternative to dedicated surface scanners. The principal advantages of photogrammetry are more rapid raw data collection, simplicity and portability of setup, and reduced equipment costs. We tested the precision and repeatability of 3D photogrammetry by comparing digital models of human crania reconstructed from conventional, 2D digital photographs to those generated using a 3D surface scanner. Overall, the photogrammetry and scanner meshes showed low degrees of deviation from one another. Surface area estimates derived from photogrammetry models tended to be slightly larger. Landmark configurations generally did not cluster together based upon whether the reconstruction was created with photogrammetry or surface scanning technology. Average deviations of landmark coordinates recorded on photogrammetry models were within the generally allowable range of error in osteometry. Thus, while dependent upon the needs of the particular research project, 3D photogrammetry appears to be a suitable, lower-cost alternative to 3D imaging and scanning options.

A new technique to determine vertical dimension of occlusion from anthropometric measurement of interpupillary distance.

Background: A number of techniques are being practiced for the evaluation of VDO, but none of them is scientifically more accurate than other. Each method advocated has its own limitations. Objectives: The purpose of this study was to find correlation between vertical dimension of occlusion (VDO) and interpupillary distance (IPD). Material and Methods: A cross-sectional study was conducted on 400 dentate subjects comprising of 200 males and 200 females. Anthropometric measurement of VDO was recorded clinically using modified digital vernier caliper. Also, a standardized digital photograph of face was generated from the frontal aspect using a digital camera for the measurement of IPD in millimeters. Correlation between VDO and IPD was studied using Spearman’s coefficient. For the execution of regression command and preparation of prediction equations to estimate VDO, Statistical Package for Social Sciences (SPSS) Software Version 11.5 was used. Results: VDO and IPD was more in males compared to females. VDO was significantly and positively correlated with IPD only in males whereas females showed a weak correlation. Hence, regression equation was derived only for males. VDO estimation using regression equation for IPD had a standard error of ± 3.94 in males. Conclusions: Since the variations between VDO and IPD are within the range of 2-4 mm, VDO prediction through this method is reliable and reproducible for male patients. Also, the method is simple, economic, and non invasive; hence it could be recommended for everyday practice to determine vertical dimension of occlusion in case of male patients. Key words:Anthropometry, interpupillary distance, jaw relation, vertical dimension of occlusion.

Outside-In Continuous Suturing Is Superior to Interrupted Suturing for Repairing Peripheral Meniscus Lesions: An In Vitro Biomechanical Study Using a Porcine Model

This in vitro biomechanical study using a porcine model compared peripheral longitudinal vertical meniscus lesion (PLVML) outside-in suture repair fixation strength using either interrupted or continuous "N" configuration No. 2-0 braided polyester sutures. Porcine lateral menisci were randomly assigned to group 1 (continuous) or group 2 (interrupted). Standardized PLVMLs were created in each specimen. Repaired specimens were placed in a specially designed clamp and loaded into a servohydraulic device. Specimens underwent preconditioning for 10 cycles (0.1 Hz, 5 to 20 N) and 500 submaximal loading cycles (0.5 Hz, 5 to 20 N), before load-to-failure testing (12.5 mm/s). A 30-second pause after preconditioning and after 10, 100, and 500 submaximal loading cycles enabled standardized digital photographs to be taken for gapping measurement determination. The failure mode was documented. Displacement and gapping during preconditioning and submaximal loading cycles did not differ between groups. Group 1 withstood a greater failure load (mean, 118.3 N; 95% confidence interval [CI], 97.2 to 139.4 N) than group 2 (mean, 63.7 N; 95% CI, 51.2 to 76.2 N) (P < .0001) and displacement during load-to-failure testing (mean, 5.3 mm; 95% CI, 4.2 to 6.5 mm) than group 2 (mean, 3.2 mm; 95% CI, 2.1 to 4.3 mm) (P = .005). Group 1 failed by suture breakage or suture pulling through tissue, whereas group 2 primarily failed by knot slippage (P < .0001). Group displacement and gapping differences were not observed after 500 submaximal loading cycles. PLVMLs repaired with a continuous N configuration, however, withstood greater load at failure and greater displacement before failure than repairs that used interrupted sutures. Continuous suture in an N configuration may improve PLVML repair fixation strength.

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores

Molecular cruciforms are X-shaped systems in which two conjugation axes intersect at a central core. If one axis of these molecules is substituted with electron-donors, and the other with electron-acceptors, cruciforms' HOMO will localize along the electron-rich and LUMO along the electron-poor axis. This spatial isolation of cruciforms' frontier molecular orbitals (FMOs) is essential to their use as sensors, since analyte binding to the cruciform invariably changes its HOMO-LUMO gap and the associated optical properties. Using this principle, Bunz and Miljanić groups developed 1,4-distyryl-2,5-bis(arylethynyl)benzene and benzobisoxazole cruciforms, respectively, which act as fluorescent sensors for metal ions, carboxylic acids, boronic acids, phenols, amines, and anions. The emission colors observed when these cruciform are mixed with analytes are highly sensitive to the details of analyte's structure and - because of cruciforms' charge-separated excited states - to the solvent in which emission is observed. Structurally closely related species can be qualitatively distinguished within several analyte classes: (a) carboxylic acids; (b) boronic acids, and (c) metals. Using a hybrid sensing system composed from benzobisoxazole cruciforms and boronic acid additives, we were also able to discern among structurally similar: (d) small organic and inorganic anions, (e) amines, and (f) phenols. The method used for this qualitative distinction is exceedingly simple. Dilute solutions (typically 10(-6) M) of cruciforms in several off-the-shelf solvents are placed in UV/Vis vials. Then, analytes of interest are added, either directly as solids or in concentrated solution. Fluorescence changes occur virtually instantaneously and can be recorded through standard digital photography using a semi-professional digital camera in a dark room. With minimal graphic manipulation, representative cut-outs of emission color photographs can be arranged into panels which permit quick naked-eye distinction among analytes. For quantification purposes, Red/Green/Blue values can be extracted from these photographs and the obtained numeric data can be statistically processed.

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores

Molecular cruciforms are X-shaped systems in which two conjugation axes intersect at a central core. If one axis of these molecules is substituted with electron-donors, and the other with electron-acceptors, cruciforms' HOMO will localize along the electron-rich and LUMO along the electron-poor axis. This spatial isolation of cruciforms' frontier molecular orbitals (FMOs) is essential to their use as sensors, since analyte binding to the cruciform invariably changes its HOMO-LUMO gap and the associated optical properties. Using this principle, Bunz and Miljanić groups developed 1,4-distyryl-2,5-bis(arylethynyl)benzene and benzobisoxazole cruciforms, respectively, which act as fluorescent sensors for metal ions, carboxylic acids, boronic acids, phenols, amines, and anions. The emission colors observed when these cruciform are mixed with analytes are highly sensitive to the details of analyte's structure and - because of cruciforms' charge-separated excited states - to the solvent in which emission is observed. Structurally closely related species can be qualitatively distinguished within several analyte classes: (a) carboxylic acids; (b) boronic acids, and (c) metals. Using a hybrid sensing system composed from benzobisoxazole cruciforms and boronic acid additives, we were also able to discern among structurally similar: (d) small organic and inorganic anions, (e) amines, and (f) phenols. The method used for this qualitative distinction is exceedingly simple. Dilute solutions (typically 10-6 M) of cruciforms in several off-the-shelf solvents are placed in UV/Vis vials. Then, analytes of interest are added, either directly as solids or in concentrated solution. Fluorescence changes occur virtually instantaneously and can be recorded through standard digital photography using a semi-professional digital camera in a dark room. With minimal graphic manipulation, representative cut-outs of emission color photographs can be arranged into panels which permit quick naked-eye distinction among analytes. For quantification purposes, Red/Green/Blue values can be extracted from these photographs and the obtained numeric data can be statistically processed.

Measurement accuracy of foramen of vesalius for safe percutaneous techniques using computer-assisted three-dimensional landmarks

The presence and description of anatomical findings about the foramen of Vesalius (FV) is important in the surgical procedure on the trigeminal nerve and/or trigeminal ganglion. This is an evaluation area for percutaneous techniques. A morphological analysis of the FVs was made in a total of 344 sides of the basis cranii of adult skulls by computerized photogrammetry using standardized digital photographs. The FV was identified in 60 specimens (34.8%). The FV was observed to be present bilaterally in 16 specimens (9.3%). The incidence of unilateral FV was 25.5% of the skulls, of which in 26 specimens (15.1%) it occurred on the left side, and in 18 specimens (10.4%) on the right side. The FV was observed to present a double opening in two specimens. The diameters of the FV were found to be 0.86 ± 0.21 (right) and 1.07 ± 0.37 mm (left). The incidence of openings with a diameter of FV 0.5 mm or more was found to be 45%. The area of the FV was calculated as 1.09 ± 0.51, and 1.4 ± 0.83 mm(2) on the right and the left, respectively. The mean distances of FV to the foramen ovale were measured as 2.30 ± 1.14 mm (right) and 2.46 ± 0.89 mm (left). The mean distances of FV to foramen spinosum were found to be 10.76 ± 1.26 mm (right) and 10.42 ± 1.29 mm (left). The findings suggest that the diameter of FV as <0.5 mm was safer to work with, while the opening types bigger than 0.5 mm opening types were highly risky for percutaneous techniques on the foramen ovale. In our study, a clear standardization has been achieved. The findings were the data obtained through computer-assisted three dimensional landmarks, appropriate for use in three dimensional planning.

Imaging Techniques in Conservation

New imaging techniques are increasingly being used within cultural heritage. This paper explores potential uses of such technologies within conservation and implications of their use on object preservation and accessibility. Study of their effects on objects is crucial because their employment is becoming irreplaceable; for example, polynomial texture mapping (PTM) has revealed previously undetectable surface features. In such cases, it is necessary to continue to use the technique to monitor object condition. 3D laser scanning, PTM, and CT scanning are investigated. Case studies are explored to investigate their current role in cultural heritage. The appropriateness of this role and whether it should be expanded is addressed by analysing advantages and disadvantages of the techniques, their feasibility, and risks caused to object preservation and accessibility. The results indicate that the technologies present some advantages over standard digital photography; PTM in particular is found to be an extremely useful, affordable technique. A more established role within conservation, especially for condition assessments, could be worthwhile. Use of the imaging techniques to create models for exhibition can also be advantageous; however, care must be taken to ensure that such models are used to enhance accessibility to original objects and not to replace them.

Preoperative Hair Removal on the Male Genitalia: Clippers vs. Razors

In an effort to reduce the incidence of postoperative surgical site infections (SSIs), many hospitals have adopted a strict practice of preoperative hair removal using clippers, as opposed to razors. However, the skin of the male genitalia is delicate, elastic with irregular skin folds and may be ill-suited for clippers. To compare shave quality and the degree of skin trauma using two methods of preoperative hair removal on the scrotal skin: clippers vs. razors. Patients undergoing surgery involving the male genitalia requiring preoperative hair removal were randomized to hair removal using clippers or a razor. Immediately following hair removal, a standardized digital photograph was taken of the male genitalia. All digital photos were evaluated in a blinded fashion by groups of urologic surgeons and surgical nurses using a standardized five-point global rating scale. The incidence of SSIs was monitored. Primary outcomes included blinded global ratings of (i) the completeness of the preoperative hair removal within the surgical field and (ii) degree of skin trauma following hair removal. The incidence of SSIs within 3 months of surgery was monitored throughout the study period. Two hundred fifteen consecutive patients were randomized (107 clipper, 108 razor). Overall, preoperative hair removal on the male genitalia using a razor resulted in significantly less skin trauma (P = 2.5E-10) and a more complete hair removal within the surgical field (P = 0.017) compared with clippers. SSIs were identified in four patients during follow-up (1.8%--two using clippers; two, razors). Our data suggest that preoperative hair removal on the scrotal skin using a razor results in less skin trauma and improved overall shave quality with no apparent increased risk of SSIs. Based on these findings, surgeons should be permitted their choice of razors or clippers for preoperative preparation of the male genitalia.

Computer-Assisted Analysis of Images for Evaluation of Long-Term Reduction Mammaplasty Results

To the Editor, Measurement methods that can evaluate breasts after reduction mammaplasty enable evaluation of changes in the breasts over time. Many researchers have focused on direct methods for measuring breast volume and size such as topography, anthropometric measurements, mammography, magnetic resonance imaging, biometric evaluations, stereophotographic techniques, the water displacement method, and measurements using special devices [1–5]. Most of these methods are time-consuming, cumbersome, and impractical for use in clinical settings. Furthermore, these techniques are not easily available, feasible, or cost effective. Moreover, some of the methods require complicated formulas for analyses. Plastic surgeons routinely use photographs to evaluate and record the preand postoperative appearance of patients. We developed a computer-assisted analysis of photographic images that can be used to evaluate shortand long-term changes after reduction mammaplasty using Adobe Photoshop CS software (Adobe systems Inc., San Jose, CA, USA). This study aimed to evaluate and compare the long-term results after reduction mammaplasty. Bottoming-out deformity, nipple transposition distance, and other distortions can be analyzed objectively using the method of analysis we developed. The method also enables selfevaluation by the surgeon, which can be used to increase knowledge about reduction mammaplasty procedures. Ewart et al. [6] reported using Adobe Photoshop software to plan surgery for two rhinoplasty patients. Karsidag et al. [7] used this software to evaluate the results of reduction mammaplasty by combining half-views of preand postoperative images in the same frame for comparison. Kreithen et al. [8] used a PowerPoint presentation for photographic comparisons of different reduction techniques. The preoperative measurements included the midclavicle-to-nipple distance, the sternal notch-to-nipple distance, the inframammary fold-to-nipple distance, the diameter of the nipple–areola complex (NAC), the width of the pedicle, and the planned postoperative NAC position. Standard anterior, lateral, and oblique digital photographs were taken with the patient in the standing position using a Nikon D100 (Nikon Inc., Melville, NY, USA) digital camera at a distance of 1.5 m. All photos were taken using a standardized position and distance with the same camera. The settings of the camera such as zoom, light, pixels, and the like were the same while the photos were taken. The same sets of photographs also were taken during the early postoperative period (B6 months) and the late postoperative period ([2 years). All measurements were routinely recorded in a database program. C. Firat Department of Plastic Surgery, Inonu University School of Medicine, Malatya, Turkey

Coronal Tooth Discoloration and White Mineral Trioxide Aggregate

IntroductionThis study assessed and characterized discoloration when white MTA (wMTA) was placed in the coronal aspect of the root canal ex vivo and the influence of red blood cells on this discoloration. MethodsCanals were prepared from the apical aspect and restored with either wMTA + saline (n = 18), wMTA + blood (n = 18), or controls (n = 4 + 4) (blood or saline alone). Color was assessed according to the CIE L*a*b* color space using standardized digital photographs at 3 time points: baseline, day 1, and day 35. Statistical analysis was performed by using 1-way analysis of variance and a 2-sample t test with P < .05. ResultsAll teeth discolored when restored with wMTA, which was most prominent in the cervical third of the crown. The presence of blood within the canal adjacent to the setting wMTA exacerbated the discoloration (P = .03). ConclusionswMTA induces the gray discoloration of the tooth crown, and the effect is compounded in the presence of blood.

Correlation analysis of alveolar bone loss in buccal/palatal and proximal surfaces in rats

The aim was to correlate alveolar bone loss in the buccal/palatal and the mesial/distal surfaces of upper molars in rats. Thirty-three, 60-day-old, male Wistar rats were divided in two groups, one treated with alcohol and the other not treated with alcohol. All rats received silk ligatures on the right upper second molars for 4 weeks. The rats were then euthanized and their maxillae were split and defleshed with sodium hypochlorite (9%). The cemento-enamel junction (CEJ) was stained with 1% methylene blue and the alveolar bone loss in the buccal/palatal surfaces was measured linearly in 5 points on standardized digital photographs. Measurement of the proximal sites was performed by sectioning the hemimaxillae, restaining the CEJ and measuring the alveolar bone loss linearly in 3 points. A calibrated and blinded examiner performed all the measurements. Intraclass Correlation Coefficient revealed values of 0.96 and 0.89 for buccal/lingual and proximal surfaces, respectively. The Pearson Correlation Coefficient (r) between measurements in buccal/palatal and proximal surfaces was 0.35 and 0.05 for the group treated with alcohol, with and without ligatures, respectively. The best correlations between buccal/palatal and proximal surfaces were observed in animals not treated with alcohol, in sites both with and without ligatures (r = 0.59 and 0.65, respectively). A positive correlation was found between alveolar bone loss in buccal/palatal and proximal surfaces. The correlation is stronger in animals that were not treated with alcohol, in sites without ligatures. Areas with and without ligature-induced periodontal destruction allow detection of alveolar bone loss in buccal/palatal and proximal surfaces.

Nasal Changes after Presurgical Nasoalveolar Molding (PNAM) in the Unilateral Cleft Lip Nose

Nasal reconstruction for patients with unilateral cleft lip and palate (UCLP) is a challenge for the reconstructive surgeon. Presurgical nasoalveolar molding (PNAM) was introduced to reshape the cleft nasal structures prior to lip repair. This study analyzed two-dimensional nasal changes before and after PNAM in patients with complete UCLP. Thirty UCLP patients (19 males; 11 females) who received PNAM before lip repair were included in this study. PNAM was applied for 100 days. Nasal casts were obtained before and after PNAM. Frontal and 45° standardized digital photographs were taken from all casts, and a photogrammetric analysis (16 linear, six angular, and two area measurements) was performed. Paired Student's t tests were used to search for differences by time, and time versus side (cleft versus noncleft). Significant reduction of cleft columella deviation with an increase in columella length, nostril height, and axial inclination on the cleft side were recorded. This resulted in an increase in the projection of the nasal tip. The noncleft measurements remained without significant changes. The cleft nostril area increased significantly more than the noncleft side by 90% with PNAM treatment. Significant normal growth changes were observed in nasal width and nasal height. A favorable reshaping of the nose after PNAM was achieved, resulting in an improvement in form before lip surgery. These changes lead to improved nasal symmetry before primary lip and nasal reconstruction in UCLP patients.

Person identification in Ethnic Indian Goans using ear biometrics and neural networks

This study presents new insights and experimental results for the use of ears as a non-invasive biometric for human identification. To determine the uniqueness of the external ear pattern two methods were employed: The Weighted Scoring System and Pattern Recognition by Neural Networks. A total of 10 external ear features classified into 37 sub-features for both right and left ears of 400 Indians of Goan origin were studied after acquiring standardized side profile digital photographs. These features were then converted to numeric scores by the ‘Weighted Scoring System’ which were then compared to ascertain the uniqueness of ear pattern in same and different individuals.Apart from this feature-wise comparison, the initially acquired photographs of 800 individual ears were scrutinized and 80 visually similar ear patterns were found. After appropriate pre-processing of five train and five test images of each of these 80 visually similar ear patterns, the images were analyzed by a specially designed software and 360 feature vectors which were the distances from the centroid to the outer edge of the ear were extracted and saved. The feature vectors of train and test images were employed to train and test the Neural Networks.The result revealed that none of the individuals in the study sample had identical weighted scores when both right and left ear scores were considered in combination or when bilateral comparison was made in the same individual. The digital analysis of visually similar ear images by Neural Networks revealed a recognition rate of 94% with an Equal Error Rate at threshold value of 0.225. The inter-individual match score among train images were found to be less than the intra-individual match scores between train and test images or the differences found in former were more than that in the latter. Also, all intra-individual scores were above the system threshold (0.225) hence accepted as match, while all inter-individual scores were below it and hence rejected as a match. An independent t-test applied to the intra- and inter-individual match scores indicated that the two distributions were significantly different (p<0.0001).Thus, this study has been successful in determining the uniqueness of ear pattern for person identification and in designing and testing software for recognition of ear patterns from side profile photographs.

Computerized Photogrammetry Used to Calculate the Brow Position Index

The orbital region is of vital importance to facial expression. Brow ptosis, besides having an impact on facial harmony, is a sign of aging. Various surgical techniques have been developed to increase the efficacy of brow-lift surgery. However, no consensus method exists for an objective measurement of the eyebrow position due to the curvature of the face. Therefore, this study aimed to establish a method for measuring the eyebrow position using computerized photogrammetry. For this study, 20 orbital regions of 10 volunteers were measured by direct anthropometry using a digital caliper and by indirect anthropometry (computerized photogrammetry) using standardized digital photographs. Lines, points, and distances were defined based on the position of the anthropometric landmarks endocanthion and exocanthion and then used to calculate the brow position index (BPI). Statistical analysis was performed using Student's t test with a significance level of 5 %. The BPI values obtained by computerized photogrammetric measurements did not differ significantly from those obtained by direct anthropometric measurements (p > 0.05). The mean BPI was 84.89 ± 10.30 for the computerized photogrammetric measurements and 85.27 ± 10.67 for the direct anthropometric measurements. The BPI defined in this study and obtained by computerized photogrammetry is a reproducible and efficient method for measuring the eyebrow position. This journal requires that authors assign a level of evidence to each article.

Evaluation of the lower incisor inclination during alignment and leveling using superelastic NiTi archwires: a laboratory study

OBJECTIVE: The aim of this laboratory study is to evaluate the influence of the shape and the length limitation of superelastic nickel-titanium (NiTi) archwires on lower incisors inclination during alignment and leveling. METHODS: Metal teeth mounted on a typodont articulator device were used to simulate a malocclusion of the mandibular arch (-3.5 mm model discrepancy). Three different shapes (Standard, Accuform and Ideal) of superelastic NiTi archwires (Sentalloy, GAC, USA) were tested. Specimens were divided in two groups: Group I, with no limitation of the archwire length; and Group II, with distal limitation. Each group had thirty specimens divided into three subgroups differentiated by the archwire shape. All groups used round wires with diameters of 0.014-in, 0.016-in, 0.018-in and 0.020-in. The recording of all intervals was accomplished using standardized digital photographs with orthogonal norm in relation to median sagittal plane. The buccolingual inclination of the incisor was registered using photographs and software CorelDraw. RESULTS: The results were obtained using ANOVA and Tukey's test at a significant level of 5%. The inclination of the lower incisor increased in both groups and subgroups. The shape of the archwire had statistically significant influence only in Group I - Standard (11.76º), Ideal (5.88º) and Accuform (1.93º). Analyzing the influence of the length limitation, despite the mean incisor tipping in Group II (3.91º) had been smaller than Group I (6.52º), no statistically significant difference was found, except for Standard, 3.89º with limitation and 11.76º without limitation. The greatest incisor tipping occurred with the 0.014-in archwires.

Biometric ratio in estimating widths of maxillary anterior teeth derived after correlating anthropometric measurements with dental measurements

To correlate dental measurements i.e. combined mesiodistal width of six maxillary anterior teeth with facial measurements i.e. inner canthal distance, interpupillary distance and intercommissural width and acquire a biometric ratio to serve as a preliminary guide in selection of the maxillary anterior teeth. In the absence of pre-extraction records, the resultant denture can lead to patient dissatisfaction towards the aesthetic appeal of their dentures. The maxillary anterior teeth play a pivotal role in denture aesthetics. Various techniques and biometric ratios have been described in literature for selection of the maxillary anteriors. This study derives a biometric ratio for the same, obtained after correlating anthropometric measurements with dental measurements. Two standardized digital photographs of the face were generated; one, when the facial muscles were relaxed and the other, when the subject was smiling; thereby, revealing the maxillary anterior teeth upto the canine tip. Inner canthal distance, interpupillary distance, intercommissural distance, distance between the tips of the maxillary canines and distance between the distal surfaces of the canines were measured. On the cast, the distance between tips of maxillary canines and distance between distal surfaces of maxillary canines were noted. The data was analysed using Spearman's rank correlation coefficient. A high correlation was found between the intercommissural measurement with distance between the tips of the canines on the photograph and between the tips of the canines on the cast with the interpupillary distance, giving a biometric ratio of 1:1.35 and 1:1.41 respectively. The least correlation was between the inner canthal distance and the tips of the canines measured on the photograph. Extra oral anthropometric measurements of the interpupillary distances and the intercommissural distances with the help of standardised photographs can help us determine the combined widths of the anterior teeth accurately, thus aiding their selection in the absence of pre-extraction records.