Αρχειοθήκη ιστολογίου

Αλέξανδρος Γ. Σφακιανάκης
ΩτοΡινοΛαρυγγολόγος
Αναπαύσεως 5
Άγιος Νικόλαος Κρήτη 72100
2841026182
6032607174

Δευτέρα 4 Απριλίου 2022

Improvement of osseointegration of Ti–6Al–4V ELI alloy orthodontic mini-screws through anodization, cyclic pre-calcification, and heat treatments

paythelady.61 shared this article with you from Inoreader
Mini-screws are widely used as temporary anchorages in orthodontic treatment, but have the disadvantage of showing a high failure rate of about 10%. Therefore, orthodontic mini-screws should have high biocompa...
View on the web

Does social support predict increased use of dental services in older men?

paythelady.61 shared this article with you from Inoreader

Abstract

Background

Past research on social support and dental visits in older people has been limited by cross-sectional design, limited social support dimensions, and non-representative samples.

Methods

Data came from men with natural teeth completing Waves 3 and 4 of the Concord Health and Ageing in Men Project (CHAMP) in Sydney, Australia. The relationship between social support at Wave 3 (2011-2012) and at least one dental visit per year at Wave 4 (2014-2016) was examined by Poisson regression. Social support was measured by structural (marital status, living arrangements, family support, social interaction) and functional (social support satisfaction) domains.

Results

There were 673 men analysed. Structural and functional social support were not associated with the pattern of usual dental visits five years later in univariable or multivariable analyses. The only consistent significant factor was income source, with older men who had other sources of income more likely to regularly visit the dentist than older men solely reliant on the pension for income (PR: 1.31, 95% CI: 1.13 – 1.52).

Conclusions

We found no differences in the pattern of usual dental visits between older men with different levels and types of social support. For older Australian men, income source seems to be the most important determinant of regular dental visits. © 2022 Australian Dental Association

View on the web

Sclerostin in Periodontal Ligament: Homeostatic Regulator in Biophysical Force‐Induced Tooth Movement

paythelady.61 shared this article with you from Inoreader

Abstract

Aim

This study elucidates the role of sclerostin in periodontal ligament (PDL) as a homeostatic regulator in biophysical force-induced tooth movement (BFTM).

Materials and Methods

BFTM was performed in rats, followed by microarray, immunofluorescence, in situ hybridization, and real-time PCR for detection and identification of the molecules. The periodontal space was analyzed via micro-computed tomography. Effects on osteoclastogenesis and bone resorption were evaluated in mouse bone marrow-derived cells. In vitro human PDL cells were subjected to biophysical forces.

Results

In the absence of BFTM, sclerostin was hardly detected in the periodontium except the PDL and alveolar bone in the furcation region and apex of the molar roots. However, sclerostin was upregulated in the PDL in vivo by adaptable force, which induced typical transfiguration without changes in periodontal space as well as in vitro PDL cells under compression and tension. In contrast, the sclerostin level was unaffected by heavy force, which caused severe degeneration of the PDL and narrowed periodontal space. Sclerostin inhibited osteoclastogenesis and bone resorption, which corroborates the accelerated tooth movement by the heavy force.

Conclusions

Sclerostin in PDL may be a key homeostatic molecule in the periodontium and a biological target for the therapeutic modulation of BFTM.

This article is protected by copyright. All rights reserved.

View on the web

Effect of Selective Carboplatin-Induced Inner Hair Cell Loss on Temporal Integration in Chinchillas

paythelady.61 shared this article with you from Inoreader

Abstract

Integration of acoustic information over time is essential for processing complex stimuli, such as speech, due to its continuous variability along the time domain. In both humans and animals, perception of acoustic stimuli is a function of both stimulus intensity and duration. For brief acoustic stimuli, as duration increases, thresholds decrease by approximately 3 dB for every doubling in duration until stimulus duration reaches 500 ms, a phenomenon known as temporal integration. Although hearing loss and damage to outer hair cells (OHC) have been shown to alter temporal integration in some studies, the role of cochlear inner hair cells (IHC) on temporal integration is unknown. Because IHC transmit nearly all acoustic information to the central auditory system and are believed to code both intensity and timing information, these sensory cells likely play a critical role in temporal integration. To test the hypothesis that selective IHC loss degrades th e temporal integration function, behaviorally trained chinchillas were treated with carboplatin, a drug known to selectively destroy IHC with little to no effect on OHC in this species. Pure-tone thresholds were assessed across frequencies (1, 2, 4, 8, 12 kHz) as a function of signal duration (500, 100, 50, 10, and 5 ms). Baseline testing showed a significant effect of duration on thresholds. Threshold decreased as a function of increasing duration, as expected. Carboplatin treatment (75 mg/kg) produced a moderate to severe loss of IHC (45–85%) with little-to-no loss of OHC. Contrary to our hypothesis, post-carboplatin temporal integration thresholds showed no significant differences from baseline regardless of stimulus duration or frequency. These data suggest that few IHC are necessary for temporal integration of simple stimuli. Temporal integration may be sensitive to loss of OHC and loss of cochlear non-linearities but does not appear to be sensitive to selectiv e IHC loss.

View on the web

Modification of an extended total temporomandibular joint replacement (eTMJR) classification system

paythelady.61 shared this article with you from Inoreader
The aims of this paper were to validate a modification of an extended total temporomandibular joint replacement (eTMJR) classification system and develop a classification schematic for ease of reference. High volume TMJ surgeons were asked to score 20 separate eTMJR devices using the updated classification system and inter-rater variability was calculated. Using the modified classification system developed, a Conger's kappa (k) coefficient of 0.53 was returned, suggesting moderate to good levels of agreement.
View on the web