41 research outputs found
Implementation of CT and IHT Processors for Invariant Object Recognition System
This paper presents PDL or ASIC implementation of key modules of invariant object recognition system based on the combination of the Incremental Hough transform (IHT), correlation and rapid transform (RT). The invariant object recognition system was represented partially in C++ language for general-purpose processor on personal computer and partially described in VHDL code for implementation in PLD or ASIC
The measurement of open apices of teeth to test chronological age of over 14-year-olds in living subjects
Age determination in living subjects is a problem of increasing interest in our community, due to the increasing numbers of individuals without
identification papers, who have immigrated illegally or committed crimes, and for whom it is necessary to verify whether they have reached the age
of 14 years in order to be charged legally.
Although the most widespread methods for age estimation refer to skeletal or dental analysis, these methods do present some drawbacks for
identification of the age of 14. The aim of the present study is to discriminate between children who are or are not 14 years of age or older by
measuring the open apices of teeth.
We evaluated the OPGs of 447 persons aged between 12 and 16 years, of Italian, Croatian and Slovenian nationality. For each individual, dental
maturity was estimated using the number of the seven left permanent mandibular teeth with root development complete, and normalized
measurement of the open apices of the third molar.
The results revealed that an individual is considered to be 14 years of age or older if all seven left permanent mandibular teeth have closed apices
and the normalized measurement of open apices of the third molar is lower than 1.1
Asymmetric Image Encryption Approach with Plaintext-Related Diffusion
This paper deals with topic of image encryption based on chaotic maps. A solution which has advantage of robustness against chosen-plaintext attacks is proposed. Permutations of image pixels are carried out in a way that enables operations on grayscale images with arbitrary resolution. All calculations done with user key and also all diffusion processes employ the same chaotic map. This feature enables usage of look-up tables which reduce computational times. The paper includes several experiments which verify achieved results and also briefly describes advantages and drawbacks of proposed solution
The effect of orthodontic tooth movement on the sensitivity of dental pulp: A systematic review and meta-analysis
Objectives: Orthodontic tooth movement (OTM) is a process that's initiated by orthodontic forces. As a consequence, the forces could restrict pulpal blood supply, possibly affecting dental pulp. The study aimed to review the available evidence on the short and long-term effects of orthodontic tooth movement on dental pulp sensitivity and to identify clinically relevant risk factors. Sources: PubMed, Embase, Scopus, and Web of Science were searched for papers from 1990 to the end of December 2021. Study selection: The studies that evaluated dental pulp sensitivity of teeth undergoing OTM were included in the systematic review. Randomized, nonrandomized and case-controlled studies were included in the analysis. Risk of bias in each study was assessed using the ROBINS-I tool. Data: The systematic search yielded an initial sample of 1110 studies, 17 were included in qualitative analysis. Most studies were classified as moderate risk of bias, however only limited long-term evidence with a higher risk of bias exists. Electric pulp test (EPT) sensitivity threshold during active OTM was increased by 4.25 SD (P < 0.001) and the relative risk (RR) of pulpal non-sensitivity was 13.27 (P < 0.001) higher compared to pre-orthodontic baseline status. Significant differences were between subgroups associated with the type of OTM. A positive relationship between pulpal non-sensitivity and mean patient age was discovered (P = 0.041). After OTM the risk of pulpal non-sensitivity remained 5.76 times higher (P < 0.001) in the long term. Conclusions: Evidence showed that OTM could affect dental pulp sensitivity. The type of OTM and patients' age were identified as clinically relevant risk factors. Clinical significance: Orthodontic tooth movement negatively impacts the sensitivity of dental pulp during active treatment and to a lesser degree in the long term. Pulpal sensitivity tests during active OTM should therefore be interpreted with caution. Data indicates younger patients have a lower risk of negative pulpal sensitivity during orthodontic treatment
Laboratory Equipment Type Fiber Optic Refractometer
Using fiber optics and micro optics technologies we designed aninnovative fiber optic index of refraction transducer that has uniqueproperties. On the base of this transducer a laboratory equipment typefiber optic refractometer was developed for liquid index of refractionmeasurements. Such refractometer may be used for medical,pharmaceutical, industrial fluid, petrochemical, plastic, food, andbeverage industry applications. For example, it may be used formeasuring the concentrations of aqueous solutions: as the concentrationor density of a solute increase, the refractive index increasesproportionately. The paper describes development work related to designof laboratory type fiber optic refractometer and describes experimentsto evaluation of its basic properties
Three-dimensional evaluation of palatal vault changes in children. A longitudinal study
OBJECTIVE: To evaluate palatal vault change in children and to assess the reliability of two palatal parameters in assessing growth modifications.
SUBJECTS AND METHODS: A group of 26 healthy white children aged 5.3 \ub1 0.3 years (15 boys, 11 girls) were randomly selected. Impressions of the upper dental arches were obtained at baseline and at 12, 18, and 30 months follow-up. Three-dimensional digital images of study casts were obtained using a laser scanning device. Palatal surface area and palatal volume were measured on the digital study casts at each time point. Effect size (ES) coefficients were calculated for both parameters as indices of diagnostic reliability in individual subjects when at least equal to 1.0.
RESULTS: Significant increases in palatal surface area and volume were seen over the observation period (P < .001). ES coefficients for palatal surface area were greater than those for palatal volume. However, even for the former parameter, only the value taken at 30 months was above the threshold.
CONCLUSIONS: Growth of the palatal vault was significant during the observation period, which coincides with primary and mixed dentition stages. Palatal surface area appears to be more reliable than palatal volume in assessment of growth modifications in individual subjects