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Sensors (Basel, Switzerland) Mar 2022For decades, optical fiber interferometers have been extensively studied and applied for their inherent advantages. With the rapid development of science and technology,... (Review)
Review
For decades, optical fiber interferometers have been extensively studied and applied for their inherent advantages. With the rapid development of science and technology, fiber sensors with higher detection sensitivity are needed on many occasions. As an effective way to improve measurement sensitivity, Vernier effect fiber sensors have drawn great attention during the last decade. Similar to the Vernier caliper, the optical Vernier effect uses one interferometer as a fixed part of the Vernier scale and the other as a sliding part of the Vernier scale. This paper first illustrates the principle of the optical Vernier effect, then different configurations used to produce the Vernier effect are classified and discussed. Finally, the outlook for Vernier effect fiber sensors is presented.
Topics: Optical Fibers
PubMed: 35408310
DOI: 10.3390/s22072694 -
Bratislavske Lekarske Listy 2012To compare anatomical measurements with that of radiological measurements.
OBJECTIVES
To compare anatomical measurements with that of radiological measurements.
BACKGROUND
The radiological measurements are commonly used in clinical practice. It is well known that the anatomical measurements are more accurate than radiological. The comparison of anatomicoradiological measurements is not reported hitherto.
METHODS
One human adult cadaveric femur bone was used for the present study. It was measured both anatomically and radiologically.
RESULTS
In digital X- ray measurements, the length from the upper lip of fovea capitis to the most prominent part of greater trochanter was 87.2 mms, from the upper most part of greater trochanter to the isthmus it was 147.9 mms, mediolateral width of medullary cavity at the isthmus was 8.9 mms, the mediolateral width at the distal root of lesser trochanter was 18.5 mms, anteroposterior width of medullary cavity at the isthmus was 11.5 mms, the anteroposterior width at the distal root of lesser trochanter was 16.8 mms. The same measurements were 91.2 mms, 154.6 mms, 11.8 mms, 19.7 mms, 11.9 mms and 18.5 mms when taken anatomically using the digital vernier caliper.
CONCLUSION
The present study showed that in all the parameters measured the radiological values were slightly lesser than the anatomical values. Considering the variations in the values, the implants can be designed for a particular case in orthopedic surgery. We believe that this study adds an important reference in the scientific literature (Tab. 1, Fig. 2, Ref. 5).
Topics: Anthropometry; Femur; Humans; Male; Radiography
PubMed: 23137208
DOI: 10.4149/bll_2012_152 -
The New England Journal of Medicine Feb 1950
Topics: Electrocardiography; Humans
PubMed: 15403341
DOI: 10.1056/NEJM195002092420605 -
Journal of Investigative and Clinical... May 2014The measurement of the thickness of the gingival tissues has been done using different techniques. Trans-gingival probing with a graduated probe, use of vernier... (Comparative Study)
Comparative Study
BACKGROUND
The measurement of the thickness of the gingival tissues has been done using different techniques. Trans-gingival probing with a graduated probe, use of vernier calipers, ultrasonography and cone-beam computed tomography (CBCT), have all been tried, but no one technique has been shown to be consistent and better than the others. The present study was done to evaluate and compare the gingival thickness as measured with a digital vernier caliper and ultrasonography.
METHODS
A total of 30 systemically healthy, non-smokers were included in the study. The gingival measurements were made and recorded from the maxillary and mandibular lateral incisor areas at 2 locations: (a) at a point apical to the free gingival groove; and (b) at a point immediately coronal to the muco-gingival junction.
RESULTS
The mean gingival thickness ranged from 0.56 to 1.02 mm. Males had a significantly thicker gingiva as compared to females (P < 0.10). Significant differences were not observed when the measurements made using the digital vernier caliper and those made with ultrasonography were compared.
CONCLUSIONS
The thickness of the gingiva was in the range of 0.56-1.02 mm. A digital vernier caliper and ultrasonography both can be used to assess the gingival thickness with equal accuracy.
Topics: Adolescent; Adult; Cephalometry; Female; Gingiva; Humans; Incisor; Male; Mandible; Maxilla; Sex Factors; Ultrasonography; Young Adult
PubMed: 23355379
DOI: 10.1111/jicd.12026 -
Maedica Dec 2020The suprascapular notch is located on the lateral part of the superior border of the scapula. The anatomical variation of the notch is considered as one of the causes...
The suprascapular notch is located on the lateral part of the superior border of the scapula. The anatomical variation of the notch is considered as one of the causes of suprascapular nerve entrapment. In the present study, we tried to evaluate the morphology and morphometry of the suprascapular notch of Indian human dry scapulae and to compare it with scapula morphometry, which is essential to understand and treat different causes of suprascapular nerve entrapment and to obtain a safe zone, which would be useful to avoid iatrogenic nerve lesion during open arthroscopic surgeries and help in designing implants for the shoulder joint. This is an observational study, with a total of 200 human dry scapulae being observed, examined and studied in detail. The type of suprascapular notch was noted as per the description given by Rengachary et al. Digital Vernier Caliper was used for classical osteometric measurements of suprascapular notch parameters, posterior limit and posterosuperior limit of safe zone along with length and width of scapulae. A statistical data analysis was done. Out of the 200,scapulae examined by us, 172 (86%) showed the presence of suprascapular notch, while nine (4.5%) showed partial ossification and 19 (9.5%) complete ossification. Six types of suprascapular notches were observed: type I,51 (25.5%); type II 45 (22.5%); type III 64 (32%); type IV 11 (5.5%); type V 9 (4.5%), and type VI 20 (10%). Type III notch was more prevalent. The study showed a moderate positive linear correlation between the width of the scapula and the safe zone of type III notch, respectively. Anatomical knowledge about the types of suprascapular notch and measurements is very helpful in the diagnosis and management of cases with shoulder pain due to suprascapular nerve entrapment and also while administering suprascapular nerve blocks for surgeries involving the shoulder region. Safe zone distances are very important for avoiding iatrogenic suprascapular nerve injuries during shoulder surgical procedures.
PubMed: 33603903
DOI: 10.26574/maedica.2020.15.4.461 -
Cranio : the Journal of... Jul 2013The aim of this study was to evaluate the intrasession-, intersession-, and interrater reliability of a vernier caliper measurement of mandible movements. The authors...
The aim of this study was to evaluate the intrasession-, intersession-, and interrater reliability of a vernier caliper measurement of mandible movements. The authors calculated the intrasession, intersession-, and interrater reliability using a plastic caliper for important mandibular parameters. All intraclass-correlation-coefficients (ICC) are at least moderately accurate, especially the values for intrasession- and intersession reliability, which were excellent. Only the interrater reliability shows greater fluctuations. Whereas the mouth opening, protrusion, and the tooth positions are reliably correct, the same was not applicable to the side movements. The lateral movement measurements were highly variable. This did not apply to other movements. Patient compliance is important along with a different mouth-opening angle. It is possible to generate a variable laterotrusion to both sides. The caliper investigated is a fast, simple, and inexpensive tool for daily work.
Topics: Adolescent; Adult; Aged; Calibration; Female; Humans; Male; Mandible; Middle Aged; Normal Distribution; Observer Variation; Overbite; Range of Motion, Articular; Reproducibility of Results; Temporomandibular Joint; Weights and Measures; Young Adult
PubMed: 23971158
DOI: 10.1179/crn.2013.028 -
Current Medical Imaging 2023This study proposes a method for improving the accuracy of three-dimensional (3D) models generated through cone-beam computed tomography (CBCT).
PURPOSE
This study proposes a method for improving the accuracy of three-dimensional (3D) models generated through cone-beam computed tomography (CBCT).
METHODS
A 3D cuboid model fitted with a ¼-scale dentition on its top surface was constructed to simulate an alveolar bone with teeth. A physical specimen of the model was printed and the distance between its opposite sides was measured using a vernier caliper. The physical model was light-scanned, and the surface data of the generated 3D model were corrected by calibrating the distance between opposite sides against the vernier caliper measurements. The physical model was also scanned using CBCT to reconstruct a second 3D model. The overall deviation between the two models and the distance deviation in each direction of the cuboid and dentition were quantified and statistically analyzed.
RESULTS
The overall deviation between the reconstructed CBCT model and the calibrated structured light-scanned model was 0.098 ± 0.001 mm. Following calibration, the overall deviation was 0.010 ± 0.006 mm. A one-way variance analysis suggested that the overall deviations' differences were not statistically significant (P < 0.05).
CONCLUSION
This study lays a solid foundation for accurate dental implantation.
Topics: Humans; Imaging, Three-Dimensional; Calibration; Spiral Cone-Beam Computed Tomography; Cone-Beam Computed Tomography
PubMed: 36799416
DOI: 10.2174/1573405619666230217121745 -
Journal of Advanced Pharmaceutical... Nov 2022Stature is the height of an individual in an upright position. It is one of the key characteristics, which helps in defining any individual. Stature estimation is needed...
Stature is the height of an individual in an upright position. It is one of the key characteristics, which helps in defining any individual. Stature estimation is needed mostly in medicolegal cases where only a limited number of human fragments are left for forensic analysis. The teeth provide essential measurements that can be used to determine stature. The aim of the study is to find out whether the second maxillary interpremolar distance can be used to effectively estimate stature of individuals. For the study, the sample size taken was 60 (30 male and 30 females), and their second maxillary interpremolar distance was measured using a digital vernier caliper. The collected data were tabulated and statistical analysis was done using SPSS software (23), followed by linear regression. For male: Y = 178.65 - 1.09X, correlation coefficient, = 0.05, For female: Y = 169.30 - 1.99X, correlation coefficient, = 0.13. Since < 0.2, there is no correlation between the interpremolar distance of the second maxillary premolar and the stature. From our study, we conclude that the interpremolar distance of the second maxillary premolar cannot be a reliable parameter for stature estimation in both genders.
PubMed: 36643103
DOI: 10.4103/japtr.japtr_216_22 -
Facial Plastic Surgery : FPS Oct 2021Photography for preoperative analysis and follow-up is indispensable for the facial plastic surgeon. The use of strobe flash units, light-emitting diode (LED) lamps, and...
Photography for preoperative analysis and follow-up is indispensable for the facial plastic surgeon. The use of strobe flash units, light-emitting diode (LED) lamps, and their position related to axis of the patient can affect the nasal contours and nasal measurements. The aim of this study was to compare the rhinoplasty pictures taken under three different lighting settings and two different positioning at 30- and 45-degree angles, and with direct measurements taken by caliper from the subjects. Standardized rhinoplasty pictures from 10 patients were taken in frontal view in a studio. These pictures were taken under three different lighting settings: built-in flash of the camera, two strobe flashes, and two LED continuous lights placed at 30 to 45 degree angles to the patient. All the pictures were uploaded to Rhinobase 2.0. In five subjects, direct measurements were done by using a Vernier caliper and compared with the computer measurements. In this study, when comparing the light sources and the angles without taking single flash into account, no relation was found between strobe lights at 30 and 45 degrees and between LED lights at 30 and 45 degrees regarding tip width, base bony width, dorsum width, interalar width, and nasal length. However, a statistically significant difference was found when the angle was changed from 30 to 45 degrees for tip width, interalar width and nasal length. The use of two LED continuous lights or two strobe lights in a studio setting has given similar results. Changing the angles of the light sources from 30 to 45 degrees affected only the tip width and the interalar width; otherwise the rest of the nasal measurements did not show any significant changes. The pictures taken at 45-degree angles to the subject showed the closest values to the direct measurements done on the patient.
Topics: Face; Humans; Lighting; Nose; Photography; Rhinoplasty
PubMed: 33742427
DOI: 10.1055/s-0041-1725939 -
British Journal of Rheumatology Dec 1989Radiogrammetry remains a convenient method of bone mass measurement. It is the only objective means of quantifying metacarpal osteoporosis (OP) in rheumatoid arthritis...
Radiogrammetry remains a convenient method of bone mass measurement. It is the only objective means of quantifying metacarpal osteoporosis (OP) in rheumatoid arthritis (RA). An automated technique using a digitizer (interfaced with an IBM PC) for measurement of combined cortical width (CCW) at the mid-shaft of six metacarpals was evaluated in three groups of individuals under 50 years of age (98 normal controls, 96 RA, 63 SLE). Intra-observer, inter-observer, and inter-institution reproducibility was assessed with a 'phantom' embedded in a rectangular mould of wax. Intra-patient variation was also assessed in RA patients seen on two occasions less than a month apart. Two hundred and fifty-seven subjects were studied. The method was found to be reproducible for a single observer, among five different observers and in two separate institutions. The RA subjects seen on two occasions showed no significant differences in CCW. The technique showed significant differences of CCW in the three groups of premenopausal subjects (controls; RA; SLE) studied (p less than 0.001). The six metacarpal bone mass was calculated in less than 5 min. The technique of digitized radiogrammetry is an improvement on the Vernier caliper technique. The method is useful for epidemiological cross-sectional studies and for evaluation of long-term radiological changes in RA.
Topics: Adult; Arthritis, Rheumatoid; Bone Density; Female; Humans; Image Processing, Computer-Assisted; Lupus Erythematosus, Systemic; Male; Metacarpus; Models, Structural; Observer Variation; Osteoporosis; Radiographic Image Enhancement; Reproducibility of Results; Sensitivity and Specificity
PubMed: 2686801
DOI: 10.1093/rheumatology/28.6.511