Search results for "Root"
showing 10 items of 1237 documents
Cross-national validation of the social media disorder scale: findings from adolescents from 44 countries
2022
Background and aims: There is currently no cross-national validation of a scale that measures problematic social media use (SMU). The present study investigated and compared the psychometric properties of the social media disorder (SMD) scale among young adolescents from different countries. Design: Validation study. Setting and participants: Data came from 222 532 adolescents from 44 countries participating in the health behaviour in school-aged children (HBSC) survey (2017/2018). The HBSC survey was conducted in the European region and Canada. Participants were on average aged 13.54 years (standard deviation = 1.63) and 51.24% were girls. Measurement: Problematic SMU was measured using th…
Simultaneous occurrence of compound odontoma and arrested root formation as developmental disturbances after maxillofacial trauma: a case report.
2009
Traumatic injury to a primary tooth and/or a bone fracture has the potential to damage the underlying permanent tooth germ which may disturb its development. The extent of the malformation depends on the developmental stage of the permanent tooth and the intensity of the trauma. The presence of infection may be a predictive factor for these abnormalities. Open surgical procedures can also potentially cause impaction and developmental disturbances. Several developmental alterations such as discolouration, hypoplasia, crown dilaceration, root angulation or dilaceration, sequestration of permanent tooth buds and disturbance in eruption have been reported in permanent teeth after trauma. Howeve…
Inhibition of rapid heat responses in nociceptive primary sensory neurons of rats by vanilloid receptor antagonists.
1999
Recent studies demonstrated that heat-sensitive nociceptive primary sensory neurons respond to the vanilloid receptor (VR) agonist capsaicin, and the first cloned VR is a heat-sensitive ion channel. Therefore we studied to what extent heat-evoked currents in nociceptive dorsal root ganglion (DRG) neurons can be attributed to the activation of native vanilloid receptors. Heat-evoked currents were investigated in 89 neurons acutely dissociated from adult rat DRGs as models for their own terminals using the whole cell patch-clamp technique. Locally applied heated extracellular solution (effective temperature ∼53°C) rapidly activated reversible and reproducible inward currents in 80% (62/80) o…
Epiphany root canal sealer prepared with resinous solvent is irritating to rat subcutaneous tissues.
2011
Objective: This study assessed the biocompatibility of the Epiphany endodontic sealer prepared with resinous solvent of Epiphany system (Thinning resin) in rat subcutaneous tissues. Study Design: Polyethylene tubes were filled with the sealer and 4 groups were established: GI, Epiphany prepared with 1 drop of resinous solvent (RS); GII, Epiphany prepared with 1 drop of RS and photoactivated; GIII, Epiphany associated with self-etch primer and prepared with 1 drop of RS; GIV, Epiphany associated with self-etch primer, prepared with 1 drop of RS and photoactivated. The filled tubes were implanted into 4 different regions of the dorsum of 20 adult male rats. Results: After 7, 14 and 21 days, a…
In vivo effects of an Er:YAG Laser, an ultrasonic system and scaling and root planing on the biocompatibility of periodontally diseased root surfaces…
2003
Background and Objectives The aim of the present study was to investigate the in vivo effects of an Er:YAG laser (ERL), an ultrasonic system and scaling and root planing (SRP) on the biocompatibility of periodontally diseased root surfaces in cultures of human periodontal ligament fibroblasts (PDL). Study Design/Materials and Methods Forty single rooted teeth, considered for extraction due to severe periodontal destruction, have been randomly assigned to the following groups: (1) ERL at 160 mJ/pulse and 10 Hz, or (2) Vector® ultrasonic system (VUS), or (3) SRP using hand instruments, or (4) untreated control (C). Immediately after instrumentation, all test and control teeth were extracted a…
Impacted maxillary canines and root resorption of adjacent teeth: a retrospective observational study
2016
Background The prevalence of impacted maxillary canine is reported to be between 1% and 3%. The lack of monitoring and the delay in the treatment of the impacted canine can cause different complications such as: displacement of adjacent teeth, loss of vitality of neighbouring teeth, shortening of the dental arch, follicular cysts, canine ankylosis, recurrent infections, recurrent pain, internal resorption of the canine and the adjacent teeth, external resorption of the canine and the adjacent teeth, combination of these factors. An appropriate diagnosis, accurate predictive analysis and early intervention are likely to prevent such undesirable effects. The objective is to evaluate, by means…
Accuracy of the estimation of dental age in comparison with chronological age in a Spanish sample of 2641 living subjects using the Demirjian and Nol…
2016
Age estimation is an important procedure in forensic medicine and is carried out for a number of reasons. For living persons, age estimation is performed in order to assess whether a child has attained the age of criminal responsibility, in scenarios involving rape, kidnapping or marriage, in premature births, adoption procedures, illegal immigration, pediatric endocrine diseases and orthodontic malocclusion, as well as in circumstances in which the birth certificate is not available or the records are suspect. According to data from the UNHCR (United Nations High Commissioner for Refugees), the number of people seeking refugee status continued to increase in the last years, driven by the w…
Differential localization of neuronal nitric oxide synthase immunoreactivity and NADPH-diaphorase activity in the cat spinal cord.
1994
The distributions of neuronal nitric oxide synthase immunoreactivity (NOS-IR) and NADPH-diaphorase (NADPH-d) activity were compared in the cat spinal cord. NOS-IR in neurons around the central canal, in superficial laminae (I and II) of the dorsal horn, in the dorsal commissure, and in fibers in the superficial dorsal horn was observed at all levels of the spinal cord. In these regions, NOS-IR paralleled NADPH-d activity. The sympathetic autonomic nucleus in the rostral lumbar and thoracic segments exhibited prominent NOS-IR and NADPH-d activity, whereas the parasympathetic nucleus in the sacral segments did not exhibit NOS-IR or NADPH-d activity. Within the region of the sympathetic autono…
Acetylsalicylic acid reduces heat responses in rat nociceptive primary sensory neurons – evidence for a new mechanism of action
2002
Acetylsalicylic acid (ASA) is thought to exert its peripheral analgesic effects via inhibition of cyclooxygenase. We now studied the effects of ASA on heat responses in primary nociceptive neurons by whole-cell patch-clamp and calcium microfluorimetry experiments. Heat-evoked inward currents in acutely dissociated rat dorsal root ganglion neurons were significantly reduced by ASA in a dose-dependent and reversible manner (IC(50) 375 nM, Hill slope -2.2, maximum effect 55%). Heat-evoked calcium transients (measured with FURA-2) were reversibly reduced by 53+/-14% (P0.05) by co-application of 1 microM ASA. The low IC(50) value, the rapid occurrence, and the reversibility of the observed effec…
Microsurgical fenestration of perineural cysts to the thecal sac at the level of the distal dural sleeve
2011
Background Surgery for symptomatic sacral perineural cysts remains an issue of discussion. Assuming micro-communications between the cyst and thecal sac resulting in a valve mechanism and trapping of CSF as a pathomechanism, microsurgical fenestration from the cyst to the thecal sac was performed to achieve free CSF communication. Methods In 13 consecutive patients (10 female, 3 male), MRI revealed sacral perineural cysts and excluded other pathologies. Micro-communication between the thecal sac and the cysts was shown by delayed contrast filling of the cysts on postmyelographic CT. Surgical fenestration achieved free CSF communication between the thecal sac and cysts in all patients. The p…