[Comparative analysis of methods to stimulate and collect dentinal fluid: a clinical and experimental study]. / Sravnitel'nyi analiz metodov stimulyatsii i zabora dentinnoi zhidkosti zuba: kliniko-eksperimental'noe issledovanie.

OBJECTIVE: The aim - to determine the most effective method of dentinal fluid collection and dentinal fluid flow rate stimulation. MATERIAL AND METHODS: In a series of dentinal fluid collection tests, 3 types of filter membranes «Technofilter¼ were compared to a blotting nitrocellulose membrane Sartorius 1288. An ability of the studied membranes to adsorb dentinal fluid was assessed based on the data of proton magnetic resonance using signal magnitudes of the organic molecules accumulation in dentine fluid samples. In the study 30 permanent teeth with a diagnosis of K04.00 «Initial pulpitis¼ were included. Teeth were randomly divided into 5 groups in accordance with the method used to stimulate the dentinal fluid flow rate. Dentinal fluid volume before and after stimulation within and between the groups was compared. RESULTS: The nitrocellulose membrane Sartorius 1288 has the highest ability to adsorb dentinal fluid; predominant dentinal fluid volume was obtained using a 10% dextran solution with low molecular weight. Based on the results of the study, the author proposed the method of dentinal fluid collection. CONCLUSION: The proposed stimulation method increases the dentinal fluid yields by 2 times in comparison with sampling under natural conditions.

Comparison of a prepCheck-supported self-assessment concept with conventional faculty supervision in a pre-clinical simulation environment.

OBJECTIVES: This study aimed to evaluate the educational outcome of a digitally based self-assessment concept (prepCheck; DentsplySirona, Wals, Austria) for pre-clinical undergraduates in the context of a regular phantom-laboratory course. MATERIALS AND METHODS: A sample of 47 third-year dental students participated in the course. Students were randomly divided into a prepCheck-supervised (self-assessment) intervention group (IG; n = 24); conventionally supervised students constituted the control group (CG; n = 23). During the preparation of three-surface (MOD) class II amalgam cavities, each IG participant could analyse a superimposed 3D image of his/her preparation against the "master preparation" using the prepCheck software. In the CG, several course instructors performed the evaluations according to pre-defined assessment criteria. After completing the course, a mandatory (blinded) practical examination was taken by all course participants (both IG and CG students), and this assessment involved the preparation of a MOD amalgam cavity. Then, optical impressions by means of a CEREC-Omnicam were taken to digitalize all examination preparations, followed by surveying and assessing the latter using prepCheck. RESULTS: The statistical analysis of the digitalized samples (Mann-Whitney U test) revealed no significant differences between the cavity dimensions achieved in the IG and CG (P = .406). Additionally, the sum score of the degree of conformity with the "master preparation" (maximum permissible 10% of plus or minus deviation) was comparable in both groups (P = .259). CONCLUSION: The implemented interactive digitally based, self-assessment learning tool for undergraduates appears to be equivalent to the conventional form of supervision. Therefore, such digital learning tools could significantly address the ever-increasing student to faculty ratio.

Conservative treatment of plantar heel pain: long-term follow-up.

In order to evaluate the long-term results of patients treated conservatively for plantar heel pain, a telephone follow-up survey was conducted. After eliminating those patients with worker's compensation-related complaints and those with documented inflammatory arthritides, data on 100 patients (58 females and 42 males) were available for review. The average patients was 48 years old (range 20-85 years). The average follow-up was 47 months (24-132 months). Clinical results were classified as good (resolution of symptoms) for 82 patients, fair (continued symptoms but no limitation of activity or work) for 15 patients, and poor (continued symptoms limiting activity or changing work status) in 3 patients. The average duration of symptoms before medical attention was sought was 6.1, 18.9, and 10 months for the three groups, respectively. The three patients with poor results all had bilateral complaints, but had no other obvious risk factors predictive of their poor result. Thirty-one patients stated that, even with the understanding that surgical treatment carries significant risk, they would have seriously considered it at the time medical attention was sought; twenty-two of these patients eventually had resolution of symptoms. Although the treatment of heel pain can be frustrating due to its indolent course, a given patient with plantar fasciitis has a very good chance of complete resolution of symptoms. There is a higher risk for continued symptoms in over-weight patients, patients with bilateral symptoms, and those who have symptoms for a prolonged period before seeking medical attention.

Joint replacement for ankylosed hips.

Forty-one fused hips in thirty-eight patients were converted to total hip replacement. The average length of follow-up was seven years. The predominant indications for conversion were progressively disabling pain in the low back or the hip, or both; loss of function due to immobility or malposition of the hip; and progressive pain and instability of the knee (usually ipsilateral). The postoperative arc of flexion averaged 87 degrees. Limb-length discrepancies improved an average of 2.5 centimeters. Postoperative function of the abductor muscles depended on the preoperative quality of those muscles and on the accuracy of the biomechanical restoration. Postoperative strength of the muscles of the hip improved for two years or more in most patients. There was complete or major relief of pain, improved mobility of the hip, and decreased dependence on supports for walking. There were nine failures: four because of sepsis, four because of loosening of the femoral component, and one because of malposition of the acetabular component. The failures were predominantly in patients who were fifty years old or less at the time of arthroplasty, patients who had had two or more previous operations, and patients who had had an injury to the hip. The quality of the results approached that after primary hip arthroplasty in older patients who have not had multiple previous operations on the hip. Survivorship analysis of the spontaneously fused hips that were treated with conventional hip replacement predicted a probability of survival of the implant of 96 per cent at thirteen years postoperatively (p = 0.048).

Excimer ablation of human intervertebral disc at 308 nanometers.

Excimer laser energy, which has been shown to photoablate tissue at a precisely controllable rate with minimal thermal damage, was applied to human intervertebral disc in an effort to develop a technique for percutaneous discectomy. Cadaveric samples of human disc were used. Excimer laser energy was produced by a XeCl, magnetically switched, long-pulse laser working at 308 nm, 20 Hz. Annulus tissue of approximately 1 mm thickness was placed in contact with the output tip of a 400 microns core diameter quartz fiber, and measurements of ablation rate were made at different radiant exposures. Ablation rates were found to vary linearly with radiant exposure, from 0.7 micron/pulse at 10 mJ/mm2 to 11.0 microns/pulse at 55 mJ/mm2, with a correlation coefficient of 0.984. Threshold radiant exposure, calculated by extrapolation, was found to be about 7 mJ/mm2. Histologic analysis showed a minimum of thermal damage in these specimens, and when ablated with modification to maintain constant fiber-tissue contact, thermal injury was nearly absent, as compared to samples ablated with Nd:YAG through a contact probe. Thermographic analysis, performed using the AGA 782 Digital Thermography system, showed increasing temperature with increasing radiant exposure, with a maximum temperature of 47.2 degrees C at 55 mJ/mm2. In that precise tissue ablation was demonstrated with minimal generated heat, and excimer energy at 308 nm is transmissible through fiber optics, excimer holds great promise for the development of a percutaneous discectomy technique.

Subungual hematoma: association with occult laceration requiring repair.

Subungual hematomas are one of the most common injuries involving the hand. On conducting a literature search, we were unable to find any studies that investigated the association between subungual hematomas, fractures, and the presence of an occult laceration of the nail bed requiring repair. Forty-seven consecutive patients who presented to the emergency department with subungual hematoma involving more than one fourth of the nail bed were included in this study. In these cases, radiographs were taken, and the nail was lifted to look for a laceration. In the subgroup of patients who had subungual hematoma associated with a fracture, all of them had a laceration requiring repair. Patients with a subungual hematoma greater than one half of the size of the nail bed had a 60% incidence of a laceration requiring repair. The authors believe that patients presenting with a subungual hematoma involving greater than one half of the nail surface and a fracture of the distal phalanx should have the nail lifted and the nail bed explored and repaired.