The medial superior olive (MSO) is a key auditory brainstem structure that receives binaural inputs and is implicated in processing interaural time disparities used for sound localization. The deaf white cat, a proven model of congenital deafness, was used to examine how deafness and cochlear implantation affected the synaptic organization ...

The marginal adaptation of metal ceramic crowns is affected by firing cycles for veneering porcelain application. The effect of multiple firings on the marginal integrity of pressable ceramic core crowns is unknown. The purpose of this in vitro study was to evaluate the effect of repeated firing cycles on the ...

Clinical use of neural controlled prosthetics has advanced in recent years, but limitations still remain, including lacking fine motor control and sensory feedback. Indwelling multi-electrode arrays, cuff electrodes, and regenerative sieve electrodes have been reported to serve as peripheral neural interfaces, though long-term stability of the nerve-electrode interface has remained ...

Auditory brainstem implants (ABIs) can provide highly beneficial hearing sensations to individuals deafened by bilateral vestibular schwannomas (neurofibromatosis type 2). Relatively little is known about the status of stimulated neurons after long-term ABI use. Direct examination of the cochlear nuclear complex (CN) of one 5-year ABI user indicated no deleterious ...

This study evaluated marginal fit of glass infiltrated alumina cores fabricated using two techniques and their marginal stability after firing cycles of veneering porcelain. Fifteen standardized all-ceramic crowns were fabricated on a metal die using each technique: slip cast technique of VITA In-Ceram sprint Alumina (Group A as control) and ...

To evaluate effects of motor neurons prostheses (MN-prosthesis) fabricated with MNs differentiated from NSCs of fetal spinal cord seeded in self-assembling peptides (sapeptides) scaffolds on functional recovery after SCI. Spinal cord hemisection was performed in adult rats. The MN-prosthesis was implanted into the lesion of injured spinal cord. TUNEL staining ...

Sharp spatial selectivity is critical to auditory performance, particularly in pitch-related tasks. Most contemporary cochlear implants have employed monopolar stimulation that produces broad electric fields, which presumably contribute to poor pitch and pitch-related performance by implant users. Bipolar or tripolar stimulation can generate focused electric fields but requires higher current ...

The hypothesis is that the mechanical mismatch between brain tissue and microelectrodes influences the inflammatory response. Our unique, mechanically adaptive polymer nanocomposite enabled this study within the cerebral cortex of rats. The initial tensile storage modulus of 5 GPa decreases to 12 MPa within 15 min under physiological conditions. The ...

In patients with severe to profound hearing loss, cochlear implants (CIs) are currently the only therapeutic option when the amplification with conventional hearing aids does no longer lead to a useful hearing experience. Despite its great success, there are patients in which benefit from these devices is rather limited. One ...

In this work, we develop an experimental testbed that couples biotic and abiotic metrics for studying, quantifying and predicting the effects of chronic electrode implantation on neural electrode performance. The rationale is based on the observation that long-term functionality is the outcome of the interactions between the dynamics of the ...

Spike detection from high data rate neural recordings is desired to ease the bandwidth bottleneck of bio-telemetry. An appropriate spike detection method should be able to detect spikes under low signal-to-noise ratio (SNR) while meeting the power and area constraints of implantation. This paper introduces a spike detection system utilizing ...

BACKGROUND: Biologic implants have been recommended for reinforcement in routine and challenging hernia repair. However, experimental and clinical studies have reported adverse effects (e.g., slow implant integration and pronounced foreign body reaction). To evaluate the impact of different material processing methods (cross-linking vs. non-cross-linking of collagen) and implant design, four ...

PURPOSE: This study tested the hypothesis that early integration of plateau root form endosseous implants is significantly affected by surgical drilling technique. MATERIALS AND METHODS: Sixty-four implants were bilaterally placed in the diaphysial radius of 8 beagles and remained 2 and 4 weeks in vivo. Half the implants had an ...

This study evaluated the effect of butylated hydroxytoluene (BHT), a lipid-soluble antioxidant, on dog sperm in chilling storage and cryopreservation. In Experiment 1, 0.2, 0.4, 0.8 and 1.6 mM BHT were supplemented to egg yolk Tris extender (EYT) and sperm were stored at 4℃ for 96 hr. Sperm motility, viability, ...

BACKGROUND: We developed a tissue-engineered biphasic cartilage bone substitute construct which has been shown to integrate with host cartilage and differs from autologous osteochondral transfer in which integration with host cartilage does not occur. QUESTIONS/PURPOSES: (1) Develop a reproducible in vitro model to study the mechanisms regulating tissue-engineered cartilage integration ...

Cryopreservation of sperm from tree shrews, which are considered primitive primates, would enhance genetic management and breeding programs. Epididymal sperm were surgically harvested from male tree shrews, cryopreserved in two Tes-Tris-based cryodiluents, and used in four experiments. In Experiment 1, there were no significant differences in motility and acrosome integrity ...

Sufficient induction of blood vessel ingrowth decisively influence transplant functionality. In this study, microvascular response to transplants of surface modified bone substitutes were assessed in vivo. The surface modification of allogenic bone substitutes (dehydrated human femoral head) was achieved in a double-conductive low-pressure gasplasma reactor (Ar(2) /O(2) , 13.65 MHz, 1,000 W, ...

Radiocapitellar stability depends, in part, on concavity-compression mechanics. This study was conducted to examine the effects of the soft tissues on radiocapitellar stability with radial head prostheses. Monopolar radial head implants are more effective in stabilizing the radiocapitellar joint than bipolar radial head prostheses, with the soft tissues intact or repaired. ...

Porous scaffold dowels of Ti(6)Al(4)V were prepared and implanted into cancellous and cortical bone sites in adult sheep. Cancellous implants were examined under gap, line-to-line, and press-fit conditions, whereas line-to-line implantation was used in cortical sites. Cortical shear strength increased significantly with time and reached 26.1 ± 8.6 MPa at ...

PURPOSE:: To investigate the use of an internal self-activated distraction device made of titanium-nickel memory alloy to augment the mandibular alveolar ridge. MATERIALS AND METHODS:: Twelve adult mongrel canines were randomly divided into 4 groups. Groups I and II were sacrificed 1 month and 3 months after distraction, respectively. In ...

The monocyte-derived macrophage is recognized as a critical determinant in biocompatibility, but its appearance in the chronic inflammatory phase is accompanied by the presence of lymphocytes, which have been much less studied in this regard. Here, we first present an overview of the physiologic continuum comprising host reactions to the ...

Here we describe our attempts to study the interaction of nanomodified surfaces with neurons and macrophages. Surfaces with nano-sized topographies produced by UV lithography, electrochemical etching, nanoimprint lithography, microdispensing, or by electrospinning of plastic nanofibers or by making plastic replicas of the extracellular matrix with nanoresolution were found to guide ...

Multielectrodes have been used with great success to simultaneously record the activity of neuronal populations in awake, behaving animals. In particular, there is great promise in the use of this technique to allow the control of neuroprosthetic devices by human patients. However, it is crucial to fully characterize the tissue ...

Implant infections remain feared and severe complications after total joint arthroplasty. The incidence of multi-resistant pathogens, causing such infections, is rising continuously, and orthopaedic surgeons are confronted with an ever-changing resistance pattern. Anti-infectious surface coatings aim for a high local effective concentration and a low systemic toxicity at the same ...

Heat-fusing is a common process for fabricating microwire tetrodes. However, it is time-consuming, and the high-temperature treatment can easily cause the insulation of the microwire to overheat leading to short circuits. We herein provide a simple, fast method to fabricate microwire tetrodes without the heat-fusion process. By increasing the twisting ...

Applications of magnesium alloys as biodegradable orthopaedic implants are critically dependent on the mechanical integrity of the implant during service. In this study, the mechanical integrity of an AZ91 magnesium alloy was studied using a constant extension rate tensile (CERT) method. The samples in two different geometries that is, circumferentially ...

Applications of magnesium alloys as biodegradable orthopaedic implants are critically dependent on the mechanical integrity of the implant during service. In this study, the mechanical integrity of an AZ91 magnesium alloy was studied using a constant extension rate tensile (CERT) method. The samples in two different geometries that is, circumferentially ...

The objective was to develop a method for cryopreserving microencapsulated canine sperm. Pooled ejaculates from three beagle dogs were extended in egg yolk tris extender and encapsulated using alginate and poly-L-lysine at room temperature. The microcapsules were cooled at 4 °C, immersed in pre-cooled extender (equivalent in volume to the ...

PURPOSE:: To evaluate the effectiveness of an orbital tissue expander designed to stimulate orbital bone growth in an anophthalmic socket. DESIGN:: Retrospective, noncomparative, interventional case series. METHODS:: settings: Institutional. Study Population: Nine consecutive patients with unilateral congenital anophthalmos. Intervention: The orbital tissue expander is made of an inflatable silicone globe ...

Tooth dilaceration refers to a dental anomaly characterized by an abrupt deviation in the longitudinal axis of tooth. Crown-root dilaceration is diagnosed in teeth with sharp angles at the cement-enamel junction. The greater the bending degree is, the less chance there is for successful teeth preservation and relocation. In this ...

Morphometrics of the molar crown is based traditionally on diameter measurements but is nowadays more often based on 2D image analysis of crown outlines. An alternative approach involves measurements at the level of the cervical line. We compare the information content of the two options in a three-dimensional (3D) digital ...

doi: 10.1111/j.1741-2358.2010.00394.x Analysis of veneer failure of removable prosthodontics ABSTRACT: Objective:  This retrospective study aimed to analyse the failure rate of the facings of double crown-retained dentures. Materials and methods:  The clinical reports of 575 patients, who received double crown-retained removable dentures with a total of 1807 double crowns between ...

This study evaluated the reliability of tooth-crown radiographic references to aid in orthodontic mini-implant insertion and showed an insertion technique based on these references. The sample consisted of 213 interradicular septa evaluated in 53 bitewing radiographs. The proximal contour of adjacent tooth crowns was used to define septum width and ...

Abstract Tooth-implant supported restorations can be temporarily cemented if the natural abutments are protected by permanently cemented copings. This in vitro study investigated the retention forces of pure titanium crowns to milled titanium alloy copings and of cobalt-chromium crowns to copings made of electroplated gold after cementation with different luting ...

To evaluate the stability of the interfacial layer and leakage patterns between enamel, DEJ, dentin and three adhesive systems as demonstrated by either a dye or a silver nitrate technique to understand the marginal integrity of restored tooth substrates. Extracted human molars were cross-sectioned to prepare enamel, DEJ and dentin ...

Summary  The epidemiology of oral rehabilitation using fixed prosthodontics has received little attention. The aim of this study was to evaluate the prevalence of single crowns, fixed partial dentures (FPDs), resin-bonded FPDs and implants in elderly Finnish patients and to identify factors that might be associated with the findings. The ...

The aim of this research was to evaluate the fatigue behavior and reliability of monolithic computer-aided design/computer-assisted manufacture (CAD/CAM) lithium disilicate and hand-layer-veneered zirconia all-ceramic crowns. A CAD-based mandibular molar crown preparation, fabricated using rapid prototyping, served as the master die. Fully anatomically shaped monolithic lithium disilicate crowns (IPS e.max ...

This study compared the effects of various surface treatments and techniques on the marginal leakage of full-coverage crowns using a quasi-three-dimensional evaluation. Crowns were cast using a gold-silver-palladium alloy by means of the lost-wax technique. Twenty-eight recently extracted human molars were divided randomly into four groups according to surface treatment ...

The aim of this study was to analyze the influence of melting and casting procedures and the cervical finish line design on the marginal fit of nickel-chromium-titanium alloy crowns. Sixty standardized specimens were prepared to receive metal-ceramic crowns and were divided into two groups according to the cervical finish line: ...

Fossil crocodyliforms discovered in recent years have revealed a level of morphological and ecological diversity not exhibited by extant members of the group. This diversity is particularly notable among taxa of the Cretaceous Period (144-65 million years ago) recovered from former Gondwanan landmasses. Here we report the discovery of a ...

This study investigated whether surface topography affects the retentive strength of cemented full crowns, comparing the effects of standard machined, sandblasted, and grooved implant abutments. Five metallic crowns per abutment type were cast and cemented with zinc phosphate. After 24 hours, the specimens were submitted to a tensile test. The ...

PURPOSE: To test the strength to failure and fracture mode of three indirect composite materials directly applied onto Ti-6Al-4V implant abutments vs cemented standard porcelain-fused-to-metal (PFM) crowns. MATERIALS AND METHODS: Sixty-four locking taper abutments were randomly allocated to four groups and were cleaned in ethanol in an ultrasonic bath for ...

The purpose of this in vitro study was to evaluate the effect of intaglio surface air-abrasion on the retention of CAD/CAM produced zirconia ceramic crowns cemented with three different types of cement. In addition the influence of artificial aging in masticatory simulator and thermocycling was tested. Extracted human premolars were ...

PURPOSE: It has been proposed that increased crown heights lead to greater crestal stresses on dental implants, crestal bone loss, and other complications. The purpose of this study was to evaluate the effect of increased crown-to-implant ratio (C/IR) on single-tooth implants. MATERIALS AND METHODS: A retrospective cohort study was conducted ...

The effect of guidance elements on the rotation of crowns was analyzed. Resin molars were prepared with curved or horizontal preparation lines. Further groups were formed with a groove or one or two boxes. Teeth were duplicated eightfold; crowns were produced and cemented with a rotational torque of 0.5 Ncm. ...

The effect of palatal wall modifications and height of a maxillary central incisor on the resistance form of metal-ceramic crowns are compared. Dies with adequate preparation height show no crown dislodgement in groups with a palatal wall, palatal wall/groove, and no palatal wall. This study suggests the use of a ...

This study evaluated the effect of framework design on the fracture resistance of metal-ceramic implant-supported crowns. Screw-retained molar crowns with a screw access hole composed of metal or porcelain were compared to a cement-retained crown (control). For each group (n = 10), five crowns were subjected to dynamic loading (1,200,000 ...

ABSTRACT Background: Knowledge on long-term clinical performance of more than 5 years on the single-implant CeraOne (Nobel Biocare AB, Gothenburg, Sweden) concept is limited. Purpose: The aim of this study is to report the long-term clinical performance of the first CeraOne single-implant restorations, installed 17 to 19 years ago. Materials ...

BACKGROUND: Developments in ceramic material science have led to improvements in the physical properties of modern ceramics, leading to a substantial increase in the clinical use of all-ceramic restorations. The authors evaluated the clinical performance of lithium disilicate (IPS e.max CAD, Ivoclar Vivadent, Amherst, N.Y.) all-ceramic crowns. METHODS: The authors ...

Full-crown restorations made by galvano forming may be considered as highly biocompatible, stable and aesthetic restorations. Therefore, they represent an alternative to conventional metal-ceramic crowns (MC), which might be associated with an allergic or toxic reaction due to metal oxides. In current literature, there are few clinical reports available, but ...