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1.
Animals (Basel) ; 13(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37508083

RESUMEN

To ensure the optimal living conditions of farm animals, it is essential to understand how their senses work and the way in which they perceive their environment. Most animals have a different hearing range compared to humans; thus, some aversive sounds may go unnoticed by caretakers. The auditory pathways may act through the nervous system on the cardiovascular, gastrointestinal, endocrine, and immune systems. Therefore, noise may lead to behavioral activation (arousal), pain, and sleep disorders. Sounds on farms may be produced by machines, humans, or animals themselves. It is worth noting that vocalization may be very informative to the breeder as it is an expression of an emotional state. This information can be highly beneficial in maintaining a high level of livestock welfare. Moreover, understanding learning theory, conditioning, and the potential benefits of certain sounds can guide the deliberate use of techniques in farm management to reduce the aversiveness of certain events.

2.
Materials (Basel) ; 16(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37297234

RESUMEN

One recommended technique for removing broken root canal instruments is to glue the fragment into a cannula adapted to it (i.e., the tube technique). The aim of the study was to determine the influence of the adhesive kind and length of the joint on the breaking force. During the investigation, 120 files (60 H-files and 60 K-files) and 120 injection needles were used. Fragments of broken files were glued into the cannula using one of three materials: cyanoacrylate adhesive, composite prosthetic cement, or glass ionomer cement. The lengths of the glued joints were 2 and 4 mm. After the polymerization of adhesives, a tensile test was carried out to find a breaking force. The results were statistically analyzed (p < 0.05). For 4 mm lengths of glued joints, the breaking force was higher than for 2 mm for both file types (K and H). In the case of K-type files, the breaking force was higher for cyanoacrylate and composite adhesives than glass ionomer cement. For H-type files, no significant difference in joint strength was found between binders at 4 mm, while at 2 mm, a much better connection was obtained for cyanoacrylate glue than prosthetic cements.

3.
Materials (Basel) ; 16(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37297332

RESUMEN

The aim of this study was to determine the bactericidal potential of graphene oxide (GO) in contact with four species of bacteria: E. coli, S. mutans, S. aureus and E. faecalis. Bacterial cell suspensions of each species were incubated in a medium containing GO, with incubation times of 5, 10, 30 and 60 min, at final concentrations of 50, 100, 200, 300 and 500 µg/mL. The cytotoxicity of GO was evaluated using live/dead staining. The results were recorded using a BD Accuri C6 flow cytofluorimeter. Obtained data were analyzed using BD CSampler software. A significant bacteria viability reduction was noted in all GO-containing samples. The antibacterial properties of GO were strongly influenced by GO concentration and incubation time. The highest bactericidal activity was observed at concentrations of 300 and 500 µg/mL for all incubation times (5, 10, 30 and 60 min). The highest antimicrobial potential was observed for E. coli: after 60 min, the mortality rate was 94% at 300 µg/mL GO and 96% at 500 µg/mL GO; the lowest was found for S. aureus-49% (300 µg/mL) and 55% (500 µg/mL).

4.
Aust Endod J ; 49(1): 92-103, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35502481

RESUMEN

The aim was to evaluate the morphology of maxillary second premolars. The root canal configurations were classified according to Vertucci and a new system by Ahmed et al. based on CBCT images. In addition, the number of roots and the level where they bifurcated were identified, and morphological measurements were performed based on anatomical landmarks. Single-rooted forms were most common. Bifurcation occurred most often in the middle part of the root. The most common canal configuration was type I according to Vertucci and code 1 SP1 according to the new classification. The measurements showing the results were as follows (mm): palatal cusp/buccal cusp/the lowest point of the occlusal surface to pulp chamber ceiling 6.18/6.54/4.77; the ceiling of the pulp chamber was found at the CEJ in 92.28% of the specimens. The maxillary second premolars tended to be single-rooted and with one root canal.


Asunto(s)
Maxilar , Raíz del Diente , Diente Premolar/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Raíz del Diente/anatomía & histología , Maxilar/diagnóstico por imagen , Cavidad Pulpar/diagnóstico por imagen , Cavidad Pulpar/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos
5.
Odontology ; 110(2): 365-375, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34714481

RESUMEN

The aim of this study was to evaluate the root and canal morphology of permanent maxillary first premolars in a Polish population using cone-beam computed tomography scanning (CBCT) and to compare the classifications by Vertucci and Ahmed et al. Images of 350 maxillary first premolars were analyzed. Scans were obtained from 226 patients: 131 women and 95 men. The root canal configurations were classified according to Vertucci and a new system by Ahmed et al. In addition, the number of roots and the level where roots bifurcated were identified. The results were submitted to statistical analysis. Most maxillary first premolars had two roots (69.1%). Most bifurcations were located in the coronal part of the root (44.2%) and the least in the apical part (15.3%). Bifurcation in the coronal part of the root was observed more often in the teeth of men than women. In turn, bifurcation in the central or apical part was significantly more common in women than in men. The most common canal configuration of the maxillary first premolars was type IV (78.2%) according to Vertucci and 2FPB1P1 (65.4%) according to the new classification. Among the remaining cases, almost all types of canals described by Vertucci, and many combinations of codes given in the new classification were demonstrated. The maxillary first premolars displayed a wide range of root and canal anatomical variations. The new system for classifying canal morphology based on Ahmed et al. is more accurate than the Vertucci classification.


Asunto(s)
Cavidad Pulpar , Raíz del Diente , Diente Premolar/anatomía & histología , Diente Premolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/diagnóstico por imagen , Femenino , Humanos , Masculino , Maxilar/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen
6.
BMC Med Imaging ; 17(1): 68, 2017 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-29284426

RESUMEN

BACKGROUND: The success of endodontic treatment is greatly affected by the location of the root canals. The purpose of this study was to evaluate the root and canal morphology of permanent maxillary first and second molars in a Polish population using cone-beam computed tomography scanning. METHODS: Cone-beam computed tomography (CBCT) scans of maxillary first and second molars the maxilla were examined. The number of roots and root canals, and the frequency of additional canals (MB2) in the mesiobuccal root canals were determined. The results were subjected to statistical analysis using the chi-square test or the chi-square test with Yates' correction. RESULTS: A total of 112 CBCT images of maxillary first (n = 185) and second molars (n = 207) from 112 patients were analyzed. All the maxillary first molars had three roots (100%). The majority of maxillary second molars had three roots (91.8%), 5.8% had two roots and 2.4% had one root. A statistically significant difference was observed between the numbers of roots in the maxillary first and second molars (p < 0.01). A statistically significant difference was also found in the distribution of the number of canals in the maxillary first and second molars (p < 0.001). The majority of maxillary first molars had four root canals (59.5%), while 40.5% had three root canals. Most maxillary second molars had three root canals (70%). Additional canals (MB2) in the mesiobuccal roots were detected significantly more frequently in the maxillary first molars than the second molars (p = 0.000) and more frequently in men than in women (p < 0.05). A higher prevalence of two canals in the mesiobuccal roots in maxillary second molars occurred in patients aged between 31 and 40 years than in patients aged between 21 and 30 years. In the maxillary first molars, the prevalence of the MB2 canal in the mesiobuccal root was almost equally distributed in the two age groups (21-30 and 31-40 years). CONCLUSION: Within the limitations of this study, it can be concluded that there are differences in the number and configuration of roots and root canals between maxillary first and second molars in the studied patients of a Polish population.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/diagnóstico por imagen , Diente Molar/anatomía & histología , Raíz del Diente/anatomía & histología , Adulto , Distribución por Edad , Cavidad Pulpar/anatomía & histología , Femenino , Humanos , Masculino , Maxilar/anatomía & histología , Polonia , Factores Sexuales , Adulto Joven
7.
Biomed Res Int ; 2017: 2704094, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28706942

RESUMEN

The aim of this study was to evaluate the sealing ability of three different canal filling techniques. Sixty-four roots of extracted human maxillary anterior teeth were prepared using ProTaper® rotary instruments. The specimens were then randomly divided into 3 experimental groups (n = 16) and 2 control groups (n = 8). The root canals were filled using cold lateral compaction (CLC group), continuous wave condensation technique using the Elements Obturation Unit® (EOU group), and ProTaper obturators (PT group). For the negative control group, 8 roots were filled using lateral compaction as in the CLC group, and the teeth were covered twice with a layer of nail varnish (NCG group). Another 8 roots were filled using lateral compaction, but without sealer, and these were used as the positive control (PCG group). A glucose leakage model was used for quantitative evaluation of microleakage for 24 hours and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 weeks. No significant difference in the cumulative amount of leakage was found between the three experimental groups at all observation times. The lateral condensation of cold gutta-percha can guarantee a similar seal of canal fillings as can be achieved by using thermal methods, in the round canals.


Asunto(s)
Materiales de Obturación del Conducto Radicular/uso terapéutico , Obturación del Conducto Radicular/instrumentación , Preparación del Conducto Radicular/instrumentación , Resinas Epoxi/química , Resinas Epoxi/uso terapéutico , Glucosa/química , Gutapercha/química , Gutapercha/uso terapéutico , Humanos , Materiales de Obturación del Conducto Radicular/química , Titanio/química
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