[A multicenter study to test the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of clinical application]

Objectives: To verify the reliability and validity of the frailty assessment scale for elderly patients with inguinal hernia and to evaluate the value of its clinical application. Methods: A convenience sampling method was used to collect 129 geriatric patients who underwent inguinal hernia surgery from January 2018 to January 2023 in nine hospitals in Liaoning Province. There were 120 males and 9 females, of whom 89 patients were 60 to <75 years old, 33 patients were 75 to <85 years old and 7 patients were ≥85 years old. The 129 patients included 11 elderly patients with inguinal hernia who had recovered from preoperative infection with COVID-19. Statistical methods such as Cronbach's coefficient, Kaiser-Meyer-Olkin test, Bartlett's test, Pearson's correlation analysis, etc. were calculated to verify the reliability indexes such as feasibility, content validity, structural validity, criterion-related validity, internal consistency reliability, and re-test reliability. Taking the 5-item modified frailty index (5-mFI) as the gold standard, the area under the curve was used to analyze the ability of the two scales to predict the occurrence of postoperative acute urinary retention, postoperative delirium, poor incision healing, operative hematoma seroma, and postoperative complications. Results: The frailty assessment scale for elderly patients with inguinal hernia showed good reliability and validity (valid completion rate of 99.2%; item content validity index of 1.000, and the scale content validity index of 1.000; exploratory factor analysis extracted a total of 1 principal component, and factor loadings of each item of 0.565 to 0.873; the AUC for frailty diagnosis using 5-mFI as the gold standard of 0.795 (P<0.01) Cronbach's coefficient of 0.916, retest reliability coefficient of 0.926), it could effectively predict postoperative acute urinary retention, delirium, hematoma seroma in the operative area and total complications (AUC of 0.746, 0.870, 0.806, and 0.738, respectively; all P<0.05), and prediction efficiency was higher than that of 5-mFI (AUC of 0.694, 0.838, 0.626 and 0.641, P<0.05 for delirium only), but both scales were inaccurate in predicting poor incision healing (AUC of 0.519, P=0.913 for the frailty assessment scale and 0.455, P=0.791 for the 5-mFI). Conclusions: The frailty assessment scale for elderly patients with inguinal hernia is reliable and significantly predicts the occurrence of postoperative adverse events in elderly inguinal hernia patients. The scale can also be used for preoperative frailty assessment in elderly patients with inguinal hernia after rehabilitation from COVID-19 infection.

[Experimental study of Ti-75(AlMoZrTi alloy) dental implants in dog mandible]

OBJECTIVE

The purpose of this study was to investigate the biocompatibility of Ti-75(AlMoZrTi Alloy) dental implants.

METHODS

Four 6.5 to 16 kg dogs were used,after mandibular cuspids and premolar extraction, 16 implants were placed and left for six or twelve months. All of the dental implants were made of Ti-75 (AlMoZrTi Alloy) and they were manufactured in two types-nonsubmerged and submerged threaded implants.

RESULTS

The survival rate of the implants was 100% (submerged implants) and 91.7% (nonsubmerged implants). Histologically,all survival implants showed some degree of intimate bone to implant contact, but one of the nonsubmerged implants showed periimplantitis. No implants were observed to be mobile. The periotest values of the dental implants were near the periotest values of the nature teeth.

CONCLUSION

This study demonstrated Ti-75 is a biocompatible material and periotest is worthy of detection of osseointegration.

[A biomechanical investigation of Ha-coated ceramic implant]

Two samples of Ha-coated ceramic implants of which sintering temperatures were 850 degrees centigrade,1050 degrees centigrade respectively,were prepared.Pure titanium implant of the same size was accomplished using a transcortical implant model in adult Mongrel dogs.Follow-up periods were 1,3 and 6 months.The results in vivo were evaluated using push-out tests and scanning electron microscope.There were significant differences in push-coated ceramic implants and pure titanium implants,especially for the 1 and 3 months follow-up period.SEM investigation of the interface after push-out test showed for the HA-coated ceramic implants to be fractured in the coating layer and for the Ti-implant to be fractured at the implant-bone interface.

[An experimental study on the HA-coated zirconia ceramic material for an endosseous implant]

HA layer is sintered onto the surface of zirconia ceramic material.These column-like composite implants and titanium implants were inserted into the femurs of the dogs.The speciments were taken at the third month after operation,and the shear strengths between the implants and bone were measured.The undecalcified bone section containing the composite ceramic implant were cut for light microscopy,scanning electron microscopy and elemental analyses of C,P and Zr.Mechanical testing results revealed that the attachment strength of HA-coated zirconia samples is more stronger,as companied with the titanium samples.Histologic evaluations of the undecalcified specimens showed that extremely close juxlaposition of bone to HA-coated zirconia ceramic implants was seen.