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Objectives: To determine the correlation between the primary implant stability quotient and the implant percussion sound frequency., Materials and Methods: A total of 14 pigs' ribs were scanned using a dental cone beam computed tomography (CBCT) scanner to classify the bone specimens into three distinct bone density Hounsfield units (HU) value categories: D1 bone: >1250 HU; D2: 850-1250 HU; D3: <850 HU. Then, 96 implants were inserted: 32 implants in D1 bone, 32 implants in D2 bone, and 32 implants in D3 bone. The primary implant stability quotient (ISQ) was analyzed, and percussion sound was recorded using a wireless microphone connected and analyzed with frequency analysis software., Results: Statistically significant positive correlations were found between the primary ISQ and the bone density HU value (r = 0.719; p < 0.001), and statistically significant positive correlations between the primary ISQ and the percussion sound frequency (r = 0.606; p < 0.001). Furthermore, significant differences in primary ISQ values and percussion sound frequency were found between D1 and D2 bone, as well as between D1 and D3 bone. However, no significant differences were found in primary ISQ values and percussion sound frequency between D2 and D3 bone., Conclusion: The primary ISQ value and the percussion sound frequency are positively correlated., (© 2024 The Author(s). Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Percussion instruments, creativity and the helping relationship are at the heart of the evolution of a rhythmic expression workshop towards a structure designed for the practice of active music therapy. Thanks to instruments within everyone's reach, the therapy based on sound production, improvisation and creativity enables patients to express themselves, communicate and create links, while constructing an identity., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Pneumonia causes the deaths of over a million people worldwide each year, with most occurring in countries with limited access to expensive but effective diagnostic methods, e.g., chest X-rays. Physical examination, the other major established method of diagnosis, suffers from several drawbacks, most notably low accuracy and high interobserver error. We sought to address this diagnostic gap by developing a proof-of-concept non-invasive device to identify the accumulation of fluid in the lungs (consolidation) characteristic of pneumonia. This device, named Tabla after the percussive instrument of the same name, utilizes the technique of auscultatory percussion; a percussive input sound is sent through the chest and recorded with a digital stethoscope for analysis. Tabla analyzes differences in sound transmission through the chest at audible frequencies as a marker for lung consolidation. This paper presents preliminary data from five pneumonia patients and eight healthy subjects. We demonstrate 92.3% accuracy in distinguishing between healthy subjects and patients with pneumonia after data analysis with a K-nearest neighbors algorithm. This prototype device is low cost and simple to implement and may offer a rapid and inexpensive method for pneumonia diagnosis appropriate for general use and in areas with limited medical infrastructure.

Fluid percussion (FP) injury model is a popular animal model of traumatic brain injury (TBI), but still there are some issues need to be addressed. To increase the validity and reliability of this technique, we adapted the FP device using electromagnetic protractor, stainless-steel cylinder, changing pressure transducer position, and foam pads to adjust the parameters of FP pulse. Besides, the adjusted FP device is more automatic. The FP pulse is promptly measured and displayed in a graphic user interface software. The modified device resulted in reliable FP pulse. The accuracy of the pendulum leveling was improved with using the electromagnetic protractor with slots. We then collected behavioral, cognition, electrophysiological, and immunohistochemical data to verify the percussion effects in TBI mice. Lateral fluid percussion injury (FPI) or sham treatment was administered at the right frontal motorsensory region of male C57BL/6J mice. TBI mice showed evident motor, cognitive, and functional impairments, characterized by evaluation of neurological, righting, geotaxis and cliff aversion reflexes, limb asymmetrical use, rotarod running, and Morris water maze testing. The neurobehavioral damages were scaled with histopathological findings. Further, the overall firing rates and theta powers in hippocampal CA1 were significantly reduced in TBI mice compared to sham mice at Days 2 and 3 after electrode implanting. The adapted device induced effects on behavior and biology in mice that agree with existing models. These findings confirmed the validity of adjustments, and the modified device may boost the interest in TBI studies., (© 2018 Wiley Periodicals, Inc.)

OBJECTIVE Experimental traumatic brain injury (TBI) models hold significant validity to the human condition, with each model replicating a subset of clinical features and symptoms. TBI is the leading cause of mortality and morbidity in children and teenagers; thus, it is critical to develop preclinical models of these ages to test emerging treatments. Midline fluid percussion injury (FPI) might best represent mild and diffuse clinical brain injury because of the acute behavioral deficits, the late onset of behavioral morbidities, and the absence of gross histopathology. In this study, the authors sought to adapt a midline FPI to postnatal day (PND) 17 and 35 rats. The authors hypothesized that scaling the craniectomy size based on skull dimensions would result in a reproducible injury comparable to the standard midline FPI in adult rats. METHODS PND17 and PND35 rat skulls were measured, and trephines were scaled based on skull size. Custom trephines were made. Rats arrived on PND10 and were randomly assigned to one of 3 cohorts: PND17, PND35, and 2 months old. Rats were subjected to midline FPI, and the acute injury was characterized. The right reflex was recorded, injury-induced apnea was measured, injury-induced seizure was noted, and the brains were immediately examined for hematoma. RESULTS The authors' hypothesis was supported; scaling the trephines based on skull size led to a reproducible injury in the PND17 and PND35 rats that was comparable to the injury in a standard 2-month-old adult rat. The midline FPI suppressed the righting reflex in both the PND17 and PND35 rats. The injury induced apnea in PND17 rats that lasted significantly longer than that in PND35 and 2-month-old rats. The injury also induced seizures in 73% of PND17 rats compared with 9% of PND35 rats and 0% of 2-month-old rats. There was also a significant relationship between the righting reflex time and presence of seizure. Both PND17 and PND35 rats had visible hematomas with an intact dura, indicative of diffuse injury comparable to the injury observed in 2-month-old rats. CONCLUSIONS With these procedures, it becomes possible to generate brain-injured juvenile rats (pediatric [PND17] and adolescent [PND35]) for studies of injury-induced pathophysiology and behavioral deficits, for which rational therapeutic interventions can be implemented.

High levels of shear stress can prevent and disrupt Pseudomonas aeruginosa biofilm formation in vitro. Intrapulmonary percussive ventilation (IPV) could be used to introduce shear stress into the lungs of cystic fibrosis (CF) patients to disrupt biofilms in vivo. We performed a first-of-its-kind pilot clinical study to evaluate short-term IPV therapy at medium (200 bursts per minute, bpm) and high frequency (400 bpm) as compared to autogenic drainage (AD) on lung function and the behavior of P. aeruginosa in the CF lung in four patients who are chronically colonized by P. aeruginosa. A significant difference between the three treatment groups was observed for both the forced expiratory volume in 1 s (FEV1) and the forced vital capacity (FVC) (p < 0.05). More specifically, IPV at high frequency significantly increased FEV1 and FVC compared to AD (p < 0.05) and IPV at medium frequency (p < 0.001). IPV at high frequency enhanced the expression levels of P. aeruginosa planktonic marker genes, which was less pronounced with IPV at medium frequency or AD. In conclusion, IPV at high frequency could potentially alter the behavior of P. aeruginosa in the CF lung and improve lung function., Trial Registration: The trail was retrospectively registered at the ISRCTN registry on 6 June 2013, under trial registration number ISRCTN75391385.

Extracorporeal membrane oxygenation (ECMO) has been used to provide "lung rest" through the use of low tidal volume (6 ml/kg) and ultralow tidal volume (<6 ml/kg) ventilation in acute respiratory distress syndrome (ARDS). Low and ultralow tidal volume ventilation can result in low dynamic respiratory compliance and potentially increased retention of airway secretions. We present our experience using automated rotational percussion beds (ARPBs) and bronchoscopy in four ARDS patients to manage increased pulmonary secretions. These beds performed automated side-to-side tilt maneuver and intermittent chest wall percussion. Their use resulted in substantial reduction in peak and plateau pressures in two patients on volume control ventilation, while the driving pressures (inspiratory pressure) to attain the desired tidal volumes in patients on pressure control ventilation also decreased. In addition, mean partial pressure of oxygen in arterial blood (PaO2)/fraction of inspired oxygen (FiO2) ratio (109 pre-ARPB vs. 157 post-ARPB), positive end-expiratory pressure (10 cm H2O vs. 8 cm H2O), and FiO2 (0.88 vs. 0.52) improved after initiation of ARPB. The improvements in the respiratory mechanics and oxygenation helped us to initiate early ECMO weaning. Based on our experience, the use of chest physiotherapy, frequent body repositioning, and bronchoscopy may be helpful in the management of pulmonary secretions in patients supported with ECMO.

Purpose: Achievement of primary stability upon surgical placement of dental implants is a key factor for successful osseointegration and depends mainly on implant-related factors. The aim of this study was to compare and assess the primary stability of implants with active and regular threads in type 2 as well as type 4 bone., Materials and Methods: Fresh cow vertebrae and a pelvis were used as models of type 4 bone and type 2 bone, respectively. Implants with two different designs-regular-threaded and active-threaded-both 4.3 mm wide and 13 mm long, were placed in both types of bone (n = 80). Stability measurements were completed by four prosthodontists using two different Periotest devices and resonance frequency analysis. Statistical analyses were performed with the Mann-Whitney U test., Results: No statistically significant differences were found between the implant types in either type of bone in the stability measured with different methods. For both implant types, the mean resonance frequency values in type 2 bone were statistically significantly higher than in type 4 bone, whereas the mean Periotest values in type 2 bone were statistically significantly lower than in type 4 bone., Conclusion: Within the limitations of this in vitro study in bone types 2 and 4, the active-threaded implant, which was invented to increase primary stability, did not show higher primary stability compared to a regular-threaded implant.

Background: A comparative ex vivo study was performed to determine electronic percussive test values (PTVs) measured by cabled and wireless electronic percussive testing (EPT) devices and to evaluate the intra- and interobserver reliability of the wireless EPT device., Methods: Forty implants were inserted into the vertebrae and forty into the pelvis of a steer, a safe distance apart. The implants were all 4.3 mm wide and 13 mm long, from the same manufacturer. PTV of each implant was measured by four different examiners, using both EPT devices, and compared. Additionally, the intra- and interobserver reliability of the wireless EPT device was evaluated., Results: Statistically significant differences (P <0.05) were observed between PTVs made by the two EPT devices. PTVs measured by the wireless EPT device were significantly higher than the cabled EPT device (P <0.05), indicating lower implant stability. The intraobserver reliability of the wireless EPT device was evaluated as excellent for the measurements in type II bone and good-to-excellent in type IV bone; interobserver reliability was evaluated as fair-to-good in both bone types., Conclusion: The wireless EPT device gives PTVs higher than the cabled EPT device, indicating lower implant stability, and its inter- and intraobserver reliability is good and acceptable.

Statement of Problem: The detection of cracks and fractures in natural teeth is a diagnostic challenge. Cracks are often not visible clinically nor detectable in radiographs., Purpose: The purpose of this study was to evaluate the diagnostic parity of quantitative percussion diagnostics, transillumination, clinical microscopy, and dye penetration., Material and Methods: Three independent examiners provided blind testing for the study. Examiner 1 transilluminated 30 extracted teeth and 23 three-dimensional copy replica control teeth and documented any visible cracks. Each tooth was then mounted in acrylic resin with a periodontal ligament substitute. Examiner 2 examined each specimen aided by the clinical microscope and transillumination and documented visible tooth cracks and fractures. Examiners 1 and 3 then independently tested all specimens with a device developed for quantitative percussion diagnostics. All visible cracks/fractures were removed with a water-cooled fine diamond rotary instrument. Crack visibility was enhanced by the use of a clinical microscope, dye penetrant, and accessory transillumination. This disassembly process was video documented/photographed for each specimen. One more quantitative percussion diagnostics testing was administered when the disassembly was complete., Results: Quantitative percussion diagnostics crack detection agreed with the gold standard microscope and transillumination method in 52 of 53 comparisons (98% agreement). Moreover, the method achieved 96% specificity and 100% sensitivity for detecting cracks and fractures in natural teeth. When all tooth cracks were removed, quantitative percussion diagnostics indicated no further structural instability., Conclusions: Quantitative percussion diagnostics can nondestructively detect cracks and fractures in natural teeth with accuracy similar to that of the clinical microscope, transillumination, and dye penetrant. In addition, the method was able to reveal the presence of many cracks that were not detected by conventional transillumination., (Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Traumatic brain injury is a leading cause of acquired epilepsy. Initially described in 1989, lateral fluid percussion injury (LFPI) has since become the most extensively used and well-characterized rodent traumatic brain injury and post-traumatic epilepsy model. Universal findings, particularly seizures that reliably develop after an initial latent period, are evident across studies from multiple laboratories. However, the LFPI procedure is a two-stage process, requiring initial surgical attachment of a skull fluid cannula and then reanesthesia for delivery of the epidural fluid pressure wave. We now describe a modification of the original technique, termed 'rapid lateral fluid percussion injury' (rLFPI), which allows for a one-stage procedure and thus shorter operating time and reduced anesthesia exposure. Anesthetized male Long-Evans rats were subjected to rLFPI through a length of plastic tubing fitted with a pipette tip cannula with a 4-mm aperture. The cannula opening was positioned over a craniectomy of slightly smaller diameter and exposed dura such that the edges of the cannula fit tightly when pressed to the skull with a micromanipulator. Fluid percussion was then delivered immediately thereafter, in the same surgery session. rLFPI resulted in nonlethal focal cortical injury in all animals. We previously demonstrated that the rLFPI procedure resulted in post-traumatic seizures and regional gliosis, but had not examined other histopathologic elements. Now, we show apoptotic cell death confined to the perilesional cortex and chronic pathologic changes such as ipsilesional ventriculomegaly that are seen in the classic model. We conclude that the rLFPI method is a viable alternative to classic LFPI, and--being a one-stage procedure--has the advantage of shorter experiment turnaround and reduced exposure to anesthetics.

Purpose: There is no quantitative gold standard instrumentation to assess the quality of implant osseointegration. The purpose of this exploratory study was to evaluate the response of two devices (one based on resonance frequency analysis, the Osstell device, and another that analyzes the percussion energy response, the Periometer) to assess the primary stability of implants embedded in artificial bone models., Materials and Methods: Standard implants were placed into polyurethane blocks of varying densities, and the two mechanical devices were challenged to test the specimen block series. Both analysis of variance and regression analysis were used to examine the output from each device over each series of specimen blocks as well as to directly compare outputs between the two devices., Results: The stability of the implants increased with the foam density for solid block specimens. Linear regression analysis showed significant correlation between the two instruments for testing with monolithic blocks ( r2 = 0.984). Both devices also indicated that a hybrid block with the greatest density at the top provided the best implant stability versus a hybrid block with relatively low density at the top of the block. However, resonance frequency analysis readings seemed to be more dependent on the density of the top layer of the hybrid blocks., Conclusion: Osstell and Periometer readings were in good agreement for monolithic blocks, and they were reasonably consistent when blocks of hybrid density were tested.

Purpose: To evaluate the primary stability of 1-stage (nonsubmerged) and 2-stage (submerged) implants via newest wireless resonance frequency (RF) analyzer and newer wireless mobility measuring (MM) device., Materials and Methods: Six 1-stage dental implants with internal hex connection and six 2-stage dental implants, 4.1 mm in diameter and 11.5 mm in length, were inserted bilaterally into the first premolar, second premolar, and first molar regions of 6 standard mandibular transparent self-curing acrylic resin models. After that, the periimplant circular bone defects were created in millimeter increments ranging between 0 and 5 mm to the same extent on all implants., Results: Implant stability quotient values significantly decreased at 1-stage and 2-stage implants when periimplant defects increased. Similar implant stability quotient values were found for both implant types; however, significantly lower MM values were noted for 2-stage implants. Irrespective of implant systems, the results indicated a significant association between wireless RF analyzer and wireless MM device., Conclusion: Both wireless RF analyzer and wireless MM device were adequate in assessing implant stability. There was no difference between 2-stage and 1-stage implant systems, except lower MM values were noted for nonsubmerged implants.

The periodontal condition was investigated by means of tooth natural frequency assessment. The correlation between tooth natural frequency and mobility was found out. The comparative estimation of percussion and spectral methods for natural frequency assessment revealed the percussion method to be more complicates because the initial acoustic signal is disturbed by external noises and hammer sound. The spectral method allows receiving reliable and reproducible results when using modified two-parametrical periodontometer.

Traumatic brain injury (TBI) research has attained renewed momentum due to the increasing awareness of head injuries, which result in morbidity and mortality. Based on the nature of primary injury following TBI, complex and heterogeneous secondary consequences result, which are followed by regenerative processes (1,2). Primary injury can be induced by a direct contusion to the brain from skull fracture or from shearing and stretching of tissue causing displacement of brain due to movement (3,4). The resulting hematomas and lacerations cause a vascular response (3,5), and the morphological and functional damage of the white matter leads to diffuse axonal injury (6-8). Additional secondary changes commonly seen in the brain are edema and increased intracranial pressure (9). Following TBI there are microscopic alterations in biochemical and physiological pathways involving the release of excitotoxic neurotransmitters, immune mediators and oxygen radicals (10-12), which ultimately result in long-term neurological disabilities (13,14). Thus choosing appropriate animal models of TBI that present similar cellular and molecular events in human and rodent TBI is critical for studying the mechanisms underlying injury and repair. Various experimental models of TBI have been developed to reproduce aspects of TBI observed in humans, among them three specific models are widely adapted for rodents: fluid percussion, cortical impact and weight drop/impact acceleration (1). The fluid percussion device produces an injury through a craniectomy by applying a brief fluid pressure pulse on to the intact dura. The pulse is created by a pendulum striking the piston of a reservoir of fluid. The percussion produces brief displacement and deformation of neural tissue (1,15). Conversely, cortical impact injury delivers mechanical energy to the intact dura via a rigid impactor under pneumatic pressure (16,17). The weight drop/impact model is characterized by the fall of a rod with a specific mass on the closed skull (18). Among the TBI models, LFP is the most established and commonly used model to evaluate mixed focal and diffuse brain injury (19). It is reproducible and is standardized to allow for the manipulation of injury parameters. LFP recapitulates injuries observed in humans, thus rendering it clinically relevant, and allows for exploration of novel therapeutics for clinical translation (20). We describe the detailed protocol to perform LFP procedure in mice. The injury inflicted is mild to moderate, with brain regions such as cortex, hippocampus and corpus callosum being most vulnerable. Hippocampal and motor learning tasks are explored following LFP.

Introduction: The purpose of this study was to analyze the evolution of implant mechanical stability in different types/sizes of bony defects using both Periotest and Osstell devices as "objective tools.", Materials and Methods: Thirty-two implants were randomly allocated to one of the four types of bone defects: marginal bone loss, peri-apical bone defect, constant width dehiscence and constant length dehiscences. Periotest/Osstell measurements were completed before and during staged bone removal (to enlarge defect size)., Results: Significant differences (P<0.05) with initial values were found after a 2 mm marginal bone removal (Osstell/Periotest); for a peri-apical bone lesion, after removal of 5 mm (Osstell) or 8 mm (Periotest); for a 6-mm-long dehiscence, after removal up to 180 degrees of the implant perimeter (Osstell/Periotest); for a 3-mm-wide dehiscence, after removal of 10 mm (Osstell) or 6 mm (Periotest)., Conclusion: Periotest and Osstell are in general not very sensitive in the identification of peri-implant bone destruction, except for marginal bone loss.

Lateral fluid percussion injury (LFPI) is the most commonly used experimental model of human traumatic brain injury (TBI). To date, investigators using this model have produced injury using a pendulum-and-piston-based device (PPBD) to drive fluid against an intact dural surface. Two disadvantages of this method, however, are (1) the necessary reliance on operator skill to position and release the pendulum, and (2) reductions in reproducibility due to variable friction between the piston's o-rings and the cylinder. To counteract these disadvantages, we designed a low-priced, novel, fluid percussion apparatus that delivers a pressure pulse of air to a standing column of fluid, forcing it against the intact dural surface. The pressure waveforms generated by this apparatus are similar to those reported in the LFPI/PPBD literature and had little variation in appearance between trials. In addition, our apparatus produced an acute and chronic TBI syndrome similar to that in the LFPI/PPBD literature, as quantified by histological changes, MRI structural changes and chronic behavioral sequelae.

Mobility of splinted teeth was determined with the help of the device Periotest, its meterage depended upon abutment fixation nature and their number. Critical for the device sensitivity was the weight of splinting construction equal to 12.71+/-0.81 g.

Background: The 1875 publications of Erb and Westphal brought widespread attention to the percussion of muscle stretch reflexes. Although the maneuver may have been observed before 1875, there is little concrete evidence of this., Objectives: To bring to light an early report of percussion eliciting the muscle stretch response., Methods: While studying the Weir Mitchell papers (Philadelphia College of Physicians), the author came across an early report of the maneuver., Results: The 531-word 1859 report, published in the Proceedings of the Academy of Natural Sciences of Philadelphia, was written by a pro tem reporter who observed Mitchell's demonstration of the phenomenon. The other attendees, including Dr. William Hammond, were so well aware of the phenomena that Dr. Mitchell "did not consider it necessary to describe them more fully." Mitchell viewed the response as muscular in nature and the relationship between this response and disease was not explored in the report., Conclusions: This 1859 report preceded the Erb and Westphal publications by nearly two decades. It is perhaps the first concrete proof that neurologists were observing this phenomenon as early as the mid-1800s. Mitchell viewed the phenomenon as a local muscle response. While the concepts that later allowed Erb to correctly interpret the phenomenon as a reflex arc were already in place, Mitchell did not synthesize these concepts.

Purpose: The purpose of this study was to investigate the validity of the current Periotest system when measuring implant systems and to present a new system to monitor implant interface integrity., Materials and Methods: The new system records an impact accelerometer signal and utilizes software for data analysis to determine the resonance frequency of an implant-abutment system. The new system uses the handpiece from the Periotest to acquire an impact signal but makes no use of the rest of the device. Tests were completed to determine the repeatability of the new system along with the effects clinical variables such as abutment torque, angulation of the handpiece, striking height, and distance handpiece is held from the abutment have on the measurement results. Accuracy of the current Periotest method as well as the new system was independently evaluated through the use of an abutment with a strain gauge attached., Results: The new system for impact testing is shown to have greater accuracy than that of the Periotest device. Additionally, the effects of handpiece distance from abutment and torque (when above 15 Ncm) were found to be negligible while angulation of the handpiece and striking height affected the resonance frequency of the new system., Conclusion: The results of the in vitro testing indicate that greater resolution and accuracy can be achieved from an impact test that utilizes a clinical measurement protocol and independent analysis of the impact accelerometer signal.

Objectives: The aim of this study is to investigate whether the damping of osseointegrated implants, as measured quantitatively with the Osstell equipment, is related to the fractal dimension of peri-implant bone., Material and Methods: Fifty-five maxillary implants in function for 3 years before the present study were investigated. Two Osstell measurements were obtained for each implant with the transducer oriented first palatally and then distally. Using the half-power bandwidth method, the damping was calculated from the frequency/amplitude plot obtained from the Osstell. Damping data were then related to the fractal dimension of peri-implant bone. Fractal dimensions were calculated using a box-counting algorithm on digitally processed intra-oral radiographs of the implants. A Spearman's test was used to verify the correlation between damping and fractal dimension values., Results: All the implants were clinically stable and free from symptoms. The mean ISQ was 63 for the palatal orientation and 71 for the distal orientation. The mean fractal dimension was 1.47; the mean damping value for palatal orientation was 12.3%, while that for the distal orientation was 8.2%. No significant correlation was found., Conclusions: Damping values, measured at peri-implant bone, were found not to be related to a radiographic parameter of trabecular bone pattern like the fractal dimension. The clinical implication would be that Osstell graphs displaying distinct or more rounded peaks might both indicate a stable implant as long as the associated implant stability quotients are in the range of satisfactory values proposed in the literature.

Objective: We compared the performance of damping capacity assessment (Periotest device) to resonance frequency analysis (Osstell device) in the assessment of peri-implant bone loss in an in vitro experiment., Material and Methods: Screw-type oral implants were polymerized into acrylic blocks. Peri-implant bone loss was simulated by successively removing defined portions of material surrounding the implants in millimeter increments. Measurement values of both devices were compared by assessing the associated measurement errors, by calculating correlation analyses and drawing scatterplots, and by means of regression analysis referring to increasing bone loss., Results: Both devices produced comparable results suggesting agreement of the measured implant stability values to the actual loss of peri-implant resin. There was a noticeable correlation of the Periotest and Osstell implant stability values., Conclusion: The results of this experiment suggest agreement in predicting the actual implant stability with both the instruments with the Osstell instrument being the more precise device.

Objectives: The aims of this in vitro study were to evaluate reliability of the Osstell and Periotest devices in the assessment of implant stability and to perform a method comparison., Material and Methods: Commercial dental implants were inserted into bovine rib segments of different anatomical origins and densities. Repeated measurements were performed, varying (a) the torque-in force of the devices' attachment screw (the Osstell transducer and the ball attachment, insert for the Periotest device), (b) the insertion site bone quality, and (c) the thread exposure in simulated peri-implant bone defects., Results: Both methods were comparably reliable and showed a strong association to each other in the classification of implant stability. As opposed to torque-forced screw attachment, the variations in bone composition, differences in inter-implant stability of adjacent implants, and peri-implant bone reduction were statistically significant for both methods., Conclusions: Both non-invasive diagnostic devices seem to be useful in the long-term follow-up of implant integration.

The objectives of this investigation were to: (i) assess the reliability of expert raters to detect ankylosis from recordings of percussion sounds, (ii) measure differences in Periotest values (PTV) between ankylosed and non-ankylosed incisors and (iii) identify characteristic differences in recorded percussion sounds from ankylosed and non-ankylosed incisors using digital sound wave analysis. A convenience sample of healthy children (age range 7-18 years) was invited to participate. Ankylosis group children had one or more documented ankylosed maxillary incisors. Control group children had intact, non-ankylosed incisors. Digital recordings of percussion sounds and PTV were acquired for each incisor of interest. Four experienced pediatric dentists rated the randomized percussion sound pairs for the presence of ankylosis. Percussion sounds were also subjected to digital sound wave analysis. Overall agreement for the expert raters was substantial (kappa = 0.7). Intra-rater agreement was substantial to almost perfect (kappa = 0.6-0.9). Diagnosis of ankylosis demonstrated sensitivity of 76-92% and specificity of 74-100%. PTV from ankylosed incisors were statistically lower than PTV from non-ankylosed incisors. Ankylosed incisor digital sound wave signals exhibited significantly more energy in high-frequency bands than non-ankylosed incisors. This investigation demonstrated that: (i) experienced pediatric dentists reliably detected ankylosis by percussion sound alone; (ii) PTV for ankylosed incisors were statistically lower than PTV from non-ankylosed incisors; and (iii) ankylosed incisors exhibited a higher proportion of their signal energy in high-frequency bands.

Peripheral-inserted central catheters (PICCs) offer a successful alternative to peripheral venipuncture for long term medication therapy. When catheters become occluded, the nurse must intervene to avoid delayed or missed treatments. Pharmacological interventions are costly and not without risks. The purpose of this exploratory study was to test a mechanical percussive POP technique to restore patency. Thirty PICC catheters were clotted with human blood and incubated for 8 hours in a 35 degrees saline bath. Using the percussive POP technique, a 10-mL syringe with 1 mL of saline restored patency in 86% of the occluded catheters. The safety and effectiveness of the POP technique in vitro was established.

Traumatic brain injury is a leading cause of death and disability, particularly among young adults. During closed head trauma, the injury process is initiated by the impact of the brain against the inner table of the calvarium. Subsequently, there is prompt initiation of a complex biochemical, cellular, and physiological injury cascade that may take days to complete. From a functional standpoint, this culminates in neurologic dysfunction and, if severe, death. This unit describes an impact-induced brain trauma model in rats which replicates nonpenetrating head injury. It does not model either penetrating or ischemic brain injuries.

The capability of placing an osseointegrated implant at the time of tooth extraction and immediately placing a restoration on the implant depends upon a number of factors. This paper describes the traditional Brånemark protocol, the evolution of single-stage surgery, the guidelines for immediate placement, the measurement of implant stability, and the considerations critical to immediately loading.

Although the deep tendon reflexes (DTRs) were first introduced simultaneously into the medical literature by Erb and Westphal (1875), there is some evidence that the knee jerk response was well known to laymen prior to that time. Erb wrote that while he was not calling attention to anything new, he realized the utility of the phenomenon in diagnosing certain disease states. Erb viewed the phenomenon more clearly as a true reflex arc, whereas Westphal interpreted it as a local muscle phenomenon. By 1885, the maneuver was used in Europe and across the Atlantic in America. By then, the DTRs had become one of the cardinal features of the neurological examination.

The purpose of the present study was to evaluate the difference in stress transfer between titanium (Ti) and hydroxyapatite (HA) by the measurement of bone marrow pressure using a catheter pressure transducer. Ti and HA implants were inserted in the tibiae of rabbits. A hole of 1 mm in diameter was drilled in the bone and a fine catheter pressure transducer was placed in the bone marrow through a tube. The top of the abutment was vertically tapped with an impulse hammer, and the acceleration signal from the hammer and pressure signal from the catheter pressure transducer were examined. The time of contact (impulse duration) recorded in the impulse with Ti and HA was 166+/-17 micro sec and 164 +/- 17 micro sec, respectively. Maximum bone marrow pressure (BMP) with Ti and HA was 54.2 +/- 32.6 and 47.5 +/- 10.0 mmHg, respectively. Variation of the BMP with Ti was significantly larger than that with HA (P < 0.05). A negative correlation coefficient between impulse duration and BMP was found. The results of the present study suggest that the stress transfer is different between Ti and HA implants using dynamics of the bone marrow pressure.

Purpose: We compare the effectiveness of mechanical percussion and inversion with observation for eliminating lower caliceal fragments 3 months after shock wave lithotripsy., Materials and Methods: At 3 months after shock wave lithotripsy 69 patients with residual lower caliceal fragments 4 mm. or less were randomized to receive either mechanical percussion and inversion or observation for 1 month. The observation group then received crossover mechanical percussion and inversion if fragments persisted. All patients were followed with plain film of the kidneys, ureters and bladder to assess the stone area and stone-free status, and renal tomography or noncontrast spiral computerized tomography to confirm stone-free status. A blinded radiologist reviewed all films. Patients were treated with a mechanical chest percussor applied to the flank while inverted to greater than 60 degrees after receiving 20 mg. furosemide., Results: A total of 35 patients were randomized to receive immediate mechanical percussion and inversion therapy and 34 observation. Of the patients in the observation group 28 subsequently received mechanical percussion and inversion after completing the observation period. The groups were not different in gender, body mass index, side affected, stone location or renal anatomical features. The mechanical percussion and inversion group had a substantially higher stone-free rate than the observation group (40% versus 3%, respectively, p <0.001). The mechanical percussion and inversion group also had a greater improvement in total stone area than controls (-63.3% versus +2.7%, respectively, p <0.001). No significant adverse effects were noted in the mechanical percussion and inversion group., Conclusions: Mechanical percussion and inversion is a safe and effective treatment option for residual lower caliceal fragments 3 months after shock wave lithotripsy. Nearly 50% of patients become stone-free, and stone burden is decreased by 50% in the remainder.

This study was designed to compare the results of immediate and delayed loading of implants with implant-retained mandibular overdentures. Ten patients (test group) received 40 Brånemark System MKII implants (4 per patient) placed in the interforaminal area of the mandible. Standard abutments were immediately screwed to the implants, rigidly connected with a bar, and immediately loaded with an overdenture. Ten patients (control group) received the same type and number of implants in the same area, but the implants were left to heal submerged. Four to 8 months later, standard abutments were screwed to the implants and the same prosthetic procedure was applied. Each implant was evaluated at the time of prosthetic loading and at 6, 12, and 24 months after the initial prosthetic load with the following parameters: modified Plaque Index (MPI), modified Bleeding Index (MBI), probing depth (PD), and Periotest. Peri-implant bone resorption was evaluated on panoramic radiographs taken 12 and 24 months after initial prosthetic loading. No significant differences were found between the 2 groups regarding MPI, MBI, Periotest, peri-implant bone resorption, and PD at 6 and 24 months (P > .05). The only difference was found regarding PD values on the mesial and lingual sites at 12 months (P < .05). The cumulative success rate of implants was 97.5% in both groups. Results from this study showed that immediate loading of endosseous implants rigidly connected with a U-shaped bar does not seem to have any detrimental effect on osseointegration. Conversely, this method significantly shortens the duration of treatment with relevant satisfaction for the patients.

The present study investigated 124 stepped-screw implants (gritblasted and acid-etched surface) placed in 104 patients immediately after tooth extraction or implant explantation and followed between August 1990 and December 1996. Implants of varying diameters and lengths were used to cover a wide range of indications in both the maxilla and mandible; 68% of the implants supported single-tooth replacements. The study parameters included Plaque Index, Gingival Index, probing depth, Periotest values, and peri-implant bone loss. Statistical analysis according to Kaplan-Meier revealed a 97% survival rate.

While the Periotest continues to be used in assessing the integrity of implants, there are numerous reports of its inconsistencies. To understand more precisely what the Periotest is actually measuring, a mathematical model was developed that illustrates the effect that various geometric and clinical parameters have on the Periotest value (PTV). In addition, the model was validated with an in vitro experiment. Results of the mathematical model are shown to correlate with those obtained from the experimental test The PTV is very sensitive to the position at which the Periotest impacts the abutment and to angulation of the handpiece. It was shown that a change in position of 1 mm in striking height can produce a difference in PTV of between 1 and 2. Since the angulation of the handpiece can produce a difference in striking position of 2 mm, it must be controlled as well. The model also showed that the Periotest can detect changes in bone height of 0.5 mm.

A method is described for estimating bone volume and contour for dental implant placement in the edentulous arch.

Statement of Problem: Immediate loading of implants may be a predictable treatment alternative when cross-arch stabilization with a fixed provisional is observed., Purpose: This study investigated the effect of immediate masticatory loading on the stability of single-standing dental implants with 4 different surfaces., Material and Methods: A total of 40 solid screw implants (diameter 3.3 mm, length 8 mm) were placed in the mandibles of 4 beagle dogs. Test groups included 3 hydroxyapatite (HA) coatings of titanium plasma-sprayed (TPS) implants. Implants with TPS alone served as control. Gold crowns were inserted 2 days after implant placement and the dogs were immediately put on a hard food diet. Implants were followed for 6 months after loading. Clinical and radiographic assessments of implants were performed at time of crown insertion (baseline) and after 1, 3, and 6 months of loading. The Periotest instrument was used for mobility measurements and radiographs were obtained for evaluation of peri-implant radiolucency and measurement of crestal bone changes., Results: Of 40 implants, 39 displayed no discernible mobility, corresponding to successful clinical function. Peri-implant radiolucencies were absent for all but the 1 mobile implant. The reduction in crestal bone levels adjacent to the implants between baseline and 6 months was statistically significant (P <.0001). No statistically significant differences in crestal bone level changes over time were found between the various coatings demonstrating the absence of a treatment effect initiated by the surface coatings., Conclusion: In this study in beagle dogs, immediate masticatory loading of single-standing dental implants did not jeopardize tissue integration, provided the implants had excellent primary stability.

Maintenance of the integrity of the abutment/implant interface is essential and is dependent on the abutment screw retaining a preload. Evaluation of this joint is usually done by manual assessment. The purpose of the current study was to determine whether the Periotest instrument could be used to evaluate abutment screw loosening. A custom-designed apparatus was constructed to measure abutment screw loosening. Abutment screws were torqued to 10, 20, 32, and 45 Ncm and then loosened. Objective assessment of screw loosening was carried out with the Periotest device. Subjective evaluation was done by 3 experienced clinicians. The Periotest was found to be more sensitive than manual detection of abutment screw loosening. With a change of 2 in the Periotest value, it was found that the tensile preload in the joint was lost. While the Periotest was more sensitive than manual evaluation, the instrument was not sensitive enough to indicate deterioration of abutment screw loosening prior to loss of tensile preload.

Statement of Problem: There are numerous articles regarding implant overloading, interfacial integrity and component failure. A significant amount of literature review supports the concept of the progressive loading and damping, and it should be addressed., Purpose: This study was designed to correlate durometer measurements of the elastomeric test materials and actual Periotest values (PTV) of the test materials as preloaded sleeve rings in Compliant Keeper abutments to support the Compliant Keeper as a viable implant damping system., Material and Methods: A 4-unit fixed-removable implant-supported partial denture was the test model. Sleeve ring combinations replaced "O" rings and 220 Periotest measurements were graphically recorded, then analyzed by least square of means, 2-way analysis of variance, and a Tukey test., Results: There was a correlation between durometer measurements and PTVs of sleeve rings. Finite movement was measured accurately with the Periotest (P =. 0001) so that Compliant Keeper systems can be programmed to match the movement of another implant abutment, because they might be able to match the PTV of a natural abutment., Conclusions: Significant differences exist between the "O" rings and sleeve rings. The sleeve ring, as a controllable damping element, enables the Compliant Keeper system to provide progressive loading and damping for implant-supported prostheses.

The paper describes a modern diagnostic method: Periotest for assessing the stability of intraosseous implants. The mobility of implants after remote and immediate implantation is assessed in 65 patients with dentition defects. The study yielded complete information on the status of tissue complex, detected the early signs of impaired bone integration after implantation, and helped more reliably predict the results.

Accurate master casts are essential for the construction of implant-supported prostheses with a precision of fit. The stability of the abutment replicas in the master cast is critical in the accurate reproduction of the patient's oral presentation. The Periotest method is an objective method of quantifying mobility in a tooth and implant. Eighteen gypsum implant master casts containing two brass abutment replicas per cast were evaluated. The abutment replicas were measured three times each for a total of 108 measurements. The mean periotest values and standard deviations were calculated for the master casts and the abutment replicas. The abutment replicas displayed mean periotest values that ranged from +1.3 to -8.0. The study shows that there are significant differences between stable and unstable implant master casts (P = 0.0001, ANOVA-Fisher's protected least significant difference) and abutment replicas (P = 0.0001, Contrast test). The Periotest method will quantify differences in gypsum stone implant master casts as well as the prosthesis supporting brass abutment replicas that are an integral part of the master cast.

Statement of Problem: Numerous reports and studies have been published relative to implant overloading, interfacial integrity, and component failure. A significant amount of literature review supports the concept of progressive loading and damping and that it should be addressed., Purpose: This article reviews the literature on load reduction and uses the Periotest instrument to evaluate the viscoelastic materials of the Compliant Keeper implant damping system in vitro., Material and Methods: The test model was a vice-mounted resin mandible replica with a 4-unit fixed-removable implant-supported Compliant Keeper partial denture. Pontics were both cantilevered and bounded. Three 13-gauge measurement extensions were located facially on the gingival, middle, and occlusal thirds of each abutment and pontic for 312 Periotest measurements of O-ring combinations with a titanium O-ring as the null control. Measurements were averaged and recorded., Results: Because the Periotest can measure finite movement below Miller Class I, Periotest values were obtained for O-rings so that they could be used to program a Compliant Keeper system to match the Periotest values of another implant body., Conclusions: Significant loading differences were found with the O-rings. The O-rings controlled the damping element so they enabled the Compliant Keeper system to provide damping and progressive loading for implant-supported prostheses.

Objective: This work presents a new technique based on the assessment of the mobility degree through the application of dynamic loads and the measurement of the tooth displacement with a laser Doppler vibrometer., Summary Background Data: Measurements of the mobility degree have been made, up to now, by the application of static loads and the measurement of the consequent displacement. The results obtained with the measurement technique proposed by Muhlemann (1967) have been validated by O'Leary et al. (1964) and by Persson and Sweson (1980). This approach, however, has not been clinically disseminated both because of the high cost of the equipment and, above all, because of the difficulty in performing the measurements., Methods: The ratio between the maximum of the tooth displacement and the input force peak has been considered as the mobility degree index. Dynamic loads have been applied and measured on teeth, with a small hammer and a load cell. The consequent displacement of tooth has been measured with a Laser Doppler vibrometer that allows easy to use and versatile noncontact measurements with high accuracy and sensitivity (< 0.1 mm/sec)., Results: An introductory in vitro study has been carried out on real teeth extracted and mounted on structures with different-stiffness silicone cast (stiffness of the support is one of the parameters responsible for teeth mobility), in order to evaluate the technique. An in vivo study has also been carried out on different teeth of a healthy patient. It is possible to observe the agreement between the O'Leary results and ones obtained in this work. The practicality of the procedure has also been demonstrated., Conclusions: Good correspondence between data available in literature and results obtained has been demonstrated. The use of the technique here proposed could allow having a deeper knowledge of the behavior of the periodontal teeth system: the tooth mobility under dynamic loads. With this new technique, it will be possible to quickly measure a pathological mobility of the tooth, before it becomes evident and problematic.

Purpose: This paper aims to establish the parameters necessary to monitor successful implant placement and osseointegration., Results and Discussion: Implant stability is considered to play a major role in the success of osseointegration. Primary implant stability at placement is a mechanical phenomenon that is related to the local bone quality and quantity, the type of implant and placement technique used. Secondary implant stability is the increase in stability attributable to bone formation and remodeling at the implant/tissue interface and in the surrounding bone. Techniques for measuring implant stability and osseointegration, including the clinical measurement of cutting resistance during implant placement and removal torque following osseointegration, are discussed. Nondestructive test methods, including impact-based techniques such as the Periotest and the Dental Fine Tester, are also discussed. An alternative method, resonance frequency analysis, is described in detail., Conclusion: It is clear that stability both at placement and during function is an important criterion for the success of dental implants. Quantitative methods, including resonance frequency analysis, can yield valuable information.

Achievement and maintenance of implant stability are prerequisites for long-term positive outcomes for osseointegrated implants. Thus, implant stability is the key to clinical success. Until recently, it was not possible for the clinician to predictably distinguish implants with different degrees of stability. Because there seems to be a correlation between implant failure and bone properties, it is possible that clinically firms implants with poor stability are more prone to failure than more stable implants. This article discusses the development and possible future use of a novel technique for clinical measurement of implant stability and osseointegration--resonance frequency analysis.

The Periotest is examined as a possible replacement for outdated, inconsistent dental implant stability diagnosis tools. The Periotest has the advantage of offering reproducible findings by measuring the levels of subclinical mobility using an ultrasonically vibrating probe. The Periotest is successful in assessing the stability status of an implant, but it can detect the quantity of bony osseointegration only in terminal cases. Radiography proved to be a more sensitive method of determining pericervical bone loss; therefore, periapical radiographs in addition to the Periotest device were found to offer the most reliable assessment of an implant's status.

The Periotest percussion force acting on a dental implant was estimated by assuming a mass-spring-dashpot model of the implant-bone system constructed on the basis of a clinical experiment. A theoretical value of about 10 N, comparable to hitherto reported experimental values, was obtained for an osseointegrated implant of about 1 g. The percussion force would probably be smaller for a heavier implant.

Clinicians elicit a Tinel's sign by tapping over a nerve site with their fingertips. No standard force has been established, and overzealous tapping can produce a false-positive "Tinel's sign" that is actually a positive percussion test. The purpose of our study was to determine a threshold force that produces a positive percussion test in each of seven nerve locations in the upper extremities of subjects with no known nerve injuries and in subjects with nerve injuries. These data suggest limits for the amount of force necessary to elicit a Tinel's sign. If these limits are adhered to, the incidence of false-positive responses may be kept low.

Periodontal jaw reflex, duration of percussion sounds, tooth mobility, and time-moment analysis of occlusal contacts by the T-scan system was recorded in nine periodontally healthy volunteers. The results showed that (i) reflex responses to the pressure applied to the uppercentageral incisors in the lingolabial direction varied, depending on the background jaw-clenching force (BCF) of the same-sided first molars. The BCF levels to elicit excitatory reflexes were 6-8 Kgf, and inhibitory reflexes were clearly elicited with a BCF of 10 Kgf and beyond. (ii) Duration of percussion sounds via an occlusal sound analyser (4.73-4.84 mS: upper first molars, 4.89-5.00 mS: uppercentageral incisors) and tooth mobility using a 'Periotest' (3.3-3.5: upper first molars, 5.5-5.6: uppercentageral incisors) showed a normal value. (iii) The time moments of occlusal contacts were symmetrical toward the midsagittal axis of the occlusal plane. The centre of the anteroposterior occlusal contacts was located in the first molar regions.