Faculty Bibliography

PURPOSE: We evaluated the operative time of microdissection testicular sperm extraction in successful and failed procedures to identify the chance of sperm retrieval during longer microsurgical procedures. MATERIALS AND METHODS: A total of 793 men with nonobstructive azoospermia underwent a first attempt at microdissection testicular sperm extraction from January 2000 to September 2009. Clinical factors were analyzed, including age, testicular volume, endocrinological data and histology. Operative time was calculated from incision until the procedure was terminated. RESULTS: Testicular sperm were successfully retrieved in 57% of the men. Sperm were found within 2, 2 to 4 and 4 to 7 hours in 89%, 30% and 37% of the men, respectively. There were no differences in preoperative clinical characteristics, age, follicle-stimulating hormone, testicular volume, incidence of a Klinefelter's syndrome diagnosis and distribution of most advanced histopathology in patients in the 3 operative time groups. In men in whom sperm were retrieved the clinical pregnancy and live birth rates were 48%, 45% and 29%, and 37%, 30% and 29% for operative times up to 2, 2 to 4 and 4 to 7 hours, respectively (p >0.05). ROC curve analysis of the different operative times for detecting sperm showed that 125 minutes was the most accurate time (AUC 0.81) with 84% sensitivity and 95% specificity. CONCLUSIONS: The chance of sperm retrieval during microdissection testicular sperm extraction was best during the first 2 hours of the operation. However, sperm were still found in up to 37% of men who required greater than 4 hours of microdissection. Retrospective analysis of our data indicated no cutoff point after which sperm retrieval was uniformly unsuccessful.

Traumatic craniofacial injuries often present as difficult reconstructive challenges for maxillofacial surgeons. Reconstruction is often complicated by significant soft tissue loss, comminuted bony fragments, a tenuous blood supply, and wound contamination. For panfacial injuries, restoration of normal facial width, facial height, and sagittal projection may be difficult to achieve. Marked swelling may limit the surgeons' ability to palpate and recognize subtle bony defects and malunion. Furthermore, a true 3-dimensional assessment of bony alignment may not be possible with traditional surgical exposures to the craniofacial skeleton. This article builds on previous work that introduced the use of 3-dimensionally guided surgery for microvascular free-flap reconstruction of the craniofacial skeleton. Use of this technology improves the planning, timing, and overall precision of microvascular reconstructive surgery. Based on this experience, a similar approach to reconstructing patients with significant craniofacial trauma has been adopted

The objective of the present study was to assess the influence of various clinically relevant scenarios on the strain distribution in the biomechanical surrounding of five different dental implant macrogeometries. The biomechanical environment surrounding an implant, i.e., the cortical and trabecular bone, was modeled along with the implant. These models included two different values of the study parameters including loading conditions, trabecular bone elastic modulus, cortical/trabecular bone thickness ratio, and bone loss for five implant designs. Finite element analysis was conducted on the models and strain in the bones surrounding the implant was calculated. Bone volumes having strains in four different windows of 0-200 muepsilon, 200-1000 muepsilon, 1000-3000 muepsilon, and > 3000 muepsilon were measured and the effect of each biomechanical variable and their two-way interactions were statistically analyzed using the analysis of variance method. This study showed that all the parameters included in this study had an effect on the volume of bones in all strain windows, except the implant design, which affected only the 0-200 muepsilon and >3000 muepsilon windows. The two-way interaction results showed that interactions existed between implant design and bone loss, and loading condition, bone loss in the 200-1000 muepsilon window, and between implant design and loading condition in the 0-200 muepsilon window. Within the limitations of the present methodology, it can be concluded that although some unfavorable clinical scenarios demonstrated a higher volume of bone in deleterious strain levels, a tendency toward the biomechanical equilibrium was evidenced regardless of the implant design.

OBJECTIVE: This study tested the hypothesis that bond strength of total- and self-etching adhesive systems to dentine is not affected by the presence of remnants from either eugenol-containing (EC) or eugenol-free (EF) temporary cements after standardized cleaning procedures. METHODS: Thirty non-carious human third molars were polished flat to expose dentine surfaces. Provisional acrylic plates were fabricated and cemented either with EC, EF or no temporary cements. All specimens were incubated for 7 days in water at 37 degrees C. The restorations were then taken out and the remnants of temporary cements were mechanically removed with a dental instrument. The dentine surfaces were cleaned with pumice and treated with either total-etching (TE) or self-etching (SE) dental adhesive systems. Atomic force microscopy was used to examine the presence of remnants of temporary cements before and after dentine cleaning procedures. Composite resin build-ups were fabricated and cemented to the bonded dentine surfaces with a resin luting cement. The specimens were then sectioned to obtain 0.9mm(2) beams for microtensile bond strength testing. Fractographic analysis was performed by optical and scanning electron microscopy. RESULTS: ANOVA showed lower mean microtensile bond strength in groups of specimens treated with EC temporary cement than in groups treated with either no cement or an EF cement (p<0.05). Mean microtensile bond strength was lower in groups employing the SE rather than the TE adhesive system (p<0.001). SE samples were also more likely to fail during initial processing of the samples. There was no evidence of interaction between cement and adhesive system effects on tensile strength. Fractographic analysis indicated different primary failure modes for SE and TE bonding systems, at the dentine-adhesive interface and at the resin cement-resin composite interface, respectively. CONCLUSION: The use of eugenol-containing temporary cements prior to indirect bonding restorations reduce, to a statistically similar extent, the bond strength of both total- and self-etching adhesive systems to dentine

This study investigated the effect of laser treatment on the fatigue resistance of a 3.5-mm diameter implant with an internal trilobe connection. Twenty two implants were embedded into acrylic resin blocks. Half the specimens were used as control group, and the other half were laser treated circumferentially around the 1.5-mm polished collar with argon shielding. Implants were fatigue tested using a step-stress accelerated lifetime test in a servo-hydraulic test machine. Despite the trend pointing towards higher fatigue resistance of laser treated specimens versus controls, step-stress analysis did not determine significant differences in the fatigue lifetimes.

The proximal interphalangeal joint (PIP) joint is the most crucial joint for the functionality of a finger. For a child with complex injury of the hand every effort should be exercised to maximize function restoration. If the PIP joint is irreparably damaged, its reconstruction is indicated. The technique of autogenic heterotopic vascularized toe joint transplantation provides unique advantage of a composite transfer of skin, tendons, bone and joint alone with growth plate and its efficacy has been affirmed in children. It has been suggested that such transfers require intact flexor tendon to achieve satisfactory results, our experience however indicates quite the contrary. As evidenced by this report of a 7-year-old boy with abrasion and avulsion injury to his dominant right hand resulting in a complex defect with skin lose, extensor, flexor avulsion along with cominution of the PIP joint of his long finger. A surgical formulation of staged reconstruction scheme including an autogenic heterotopic vascularized toe joint transplantation led to complete functional restoration to his right hand. (c) 2011 Wiley-Liss, Inc. Microsurgery 2011

BACKGROUND: Unintentional injury is a leading cause of preventable mortality in elderly populations and is most often related to accidental falls and motor vehicle accidents. Hispanic ethnicity has been previously associated with decreased risk of accidental fall death as well as improved outcomes in other health states, the "Hispanic paradox." A timely analysis of national data with consideration for multiple injury types and age could provide insight into this epidemiologic phenomenon and help guide the use of prevention efforts. MATERIALS AND METHODS: Search of the Center for Disease Control's WISQARS database was performed to identify the number of fatalities in the U.S. between 2003 and 2006 by age group, gender, Hispanic ethnicity, and injury type. Total U.S. population and group populations for the years examined were obtained from the U.S. Census Bureau's American Community Survey for each year. Mortality was calculated as fatalities over the total group population for the years examined. RESULTS: Independent of gender and age group, elderly Hispanics were at decreased risk of death from accidental fall or as an occupant in a motor vehicle accident, but increased risk of pedestrian fatality compared with white-NH. CONCLUSIONS: The reduced fall and occupant mortality seen in elderly Hispanic populations may come at the cost of increased pedestrian-related mortality. This is consistent with and likely reflects differences in culture, socioeconomic status, and geographic distribution for the U.S. Hispanic population. Effective targeting of injury prevention programs, especially community based, should consider the role of Hispanic ethnicity and its impact on lifestyle.

BACKGROUND: The free anterolateral thigh (ALT) flap has become a reconstructive workhorse with great versatility throughout the body. However, the utility of the pedicled ALT flap is less described for complex defects. A skin paddle with reliable blood circulation and wide range of reach, low donor site morbidity along with the avoidance of many of the complications plaguing free flaps, are just some of the several benefits offered by the pedicled ALT flap. We investigated specific clinical examples within our ALT flap database where the pedicled ALT flap was used for coverage of complex wounds and highlight its advantages. METHODS: We conducted a retrospective chart review on those patients in whom a pedicled ALT flap was used for complex wound reconstruction over a 7-year period between July 2002 and October 2009 at The R Adams Cowley Shock Trauma Center performed by a single surgeon. RESULTS: : Four patients underwent a pedicled ALT flap as part of their reconstruction. Flaps ranged in size from 75 to 648 cm, and all but one were cutaneous in nature with the other one being fasciocutaneous. The flaps averaged 2 perforators (range, 1-3) and the donor sites were all closed primarily except for one. CONCLUSIONS: When faced with a complex defect in the abdominal-pelvic region, we propose that the pedicled ALT flap has several advantages to other types of tissue coverage and is an excellent option for the reconstructive surgeon.

PURPOSE: We studied factors that can predict successful repeat microdissection testicular sperm extraction in men with nonobstructive azoospermia. MATERIALS AND METHODS: We retrospectively analyzed the records of 126 men with nonobstructive azoospermia who underwent 1 successful microdissection testicular sperm extraction attempt. Clinical factors identifiable at the second procedure, including age, testicular volume, endocrinological data and histology, were analyzed. RESULTS: Overall testicular spermatozoa were successfully retrieved at 103 of 126 repeat attempts (82%). Men with a successful repeat attempt had lower follicle-stimulating hormone (mean+/-SD 23.1+/-12.4 vs 29.2+/-12.8, p=0.04) and larger testicular volume (mean 10+/-5 vs 7+/-4, p=0.0001) at the repeat procedure compared to men with a failed repeat attempt. Adjusted associations from a multiple logistic regression model showed that no factors predicted sperm retrieval during repeat microdissection testicular sperm extraction. An ROC curve showed a fair prediction model (AUC=0.71). CONCLUSIONS: The follicle-stimulating hormone level and testicular volume at the repeat attempt appear to have predictive value to determine the success of a second attempt. These observations are interesting since testicular volume and follicle-stimulating hormone in men with nonobstructive azoospermia do not predict sperm retrieval at a primary microdissection testicular sperm extraction attempt.