Faculty Bibliography

OBJECTIVES: To define the role of crossing vessels in the pathophysiology of ureteropelvic junction (UPJ) obstruction, we analyzed the relationship between the presence of crossing vessels and UPJ pathologic findings in patients undergoing laparoscopic pyeloplasty. The significance of crossing renal vessels in patients with UPJ obstruction is unclear. METHODS: We performed a retrospective analysis of 155 consecutive patients undergoing laparoscopic pyeloplasty. Pathologic specimens from the UPJ were evaluated in 95 patients. The presence or absence of crossing vessels was documented intraoperatively. The histopathologic findings allowed for categorization into 5 groups: group 1, normal ureteral tissue; group 2, chronic inflammation; group 3, smooth muscle hypertrophy, group 4, fibrosis; and group 5, smooth muscle atrophy. The pathologic findings between patients with and without crossing vessels were compared. RESULTS: Overall, crossing vessels were identified in 98 patients (63.2%). Of the 95 cases with specimens retrieved for histologic analysis, 65 had crossing vessels and 30 did not. The most common UPJ histologic finding in patients with crossing vessels was no intrinsic abnormality (43%). In contrast, this was seen in only 10% of patients without a crossing vessel. In the group without crossing vessels, chronic inflammation (40%) was the predominant histologic findings. Patients with a crossing vessel were less likely to have intrinsic histologic pathologic findings (P < .0003). CONCLUSIONS: Patients with crossing vessels and UPJ obstruction had no histologic abnormalities identified in 43% of cases. This finding implicates crossing vessels in the pathogenesis of select cases of UPJ obstruction and direct mechanical compression as the etiology of obstruction in these individuals

BACKGROUND: Patients presenting with traumatic craniomaxillofacial fractures often have occult concomitant injuries. This study was designed to determine whether facial fracture patterns are associated with a particular constellation of concomitant head and neck injuries. METHODS: A retrospective review of 4786 consecutive patients diagnosed with maxillofacial fractures at a dedicated urban trauma center from 1998 to 2005 was conducted; maxillofacial fractures and cervical spine injuries were grouped by dividing the craniomaxillofacial skeleton and cervical spine into thirds. Univariate and multivariate logistic regression analyses were used to identify associations between facial fractures and other traumatic injuries. RESULTS: Among all patients with facial fractures, 461 (9.7 percent) also had cervical spine injuries and 2175 (45.5 percent) had associated head injuries. Fractures of the upper face were associated with increased likelihood of mid lower cervical spine injuries, severe intracranial injuries, and increased mortality rates. Unilateral mandible injuries were associated with an increased likelihood of having upper cervical spine injuries, whereas unilateral midface injuries were associated with basilar skull fractures and several intracranial injuries. Finally, bilateral midface injuries were associated with basilar skull fracture and death. CONCLUSIONS: Craniomaxillofacial fractures are commonly associated with head and cervical spine injuries that involve predictable patterns of force dispersion from the maxillofacial skeleton and transmission to the cranial vault and cervical spine. These results suggest that concomitant injuries should be investigated closely with distinct types of facial fractures.

Societal changes, including the aging of the US population and the lack of routine dental service coverage under Medicare, have left many seniors unable to afford any dental care whatsoever, let alone the most advanced treatments.(1) In 2004, the Columbia University College of Dental Medicine and its partners instituted the ElderSmile program in the largely impoverished communities of Harlem and Washington Heights/Inwood in New York City. The long-term goal of this program is to improve access to and delivery of oral health care for seniors; the short-term goal is to establish and operate a network of prevention centers surrounding a limited number of treatment centers. Preliminary results indicate substantial unmet dental needs in this largely Hispanic and Black elderly population.

Of all the methods for repair of the unilateral cleft lip, none has gained as much popularity as the rotation-advancement. Millard's original principle of 50 years ago continues to guide surgeons in closure of the cleft lip. Unlike earlier procedures, the brilliance of the rotation-advancement is that it permits individual manipulation and modifications while maintaining Millard's original surgical and anatomical goals. Millard and many other surgeons have made modifications to adjust the procedure to each specific patient, to address some of its faults, and to gain new advantages. In this article, the authors review the techniques of Drs. Ralph Millard, Steve Byrd, Court Cutting, John Mulliken, and Samuel Stal. The variations from Millard's original technique are highlighted, including a discussion of the benefits of each modification

Patients who have developmental disabilities and epilepsy can be safely treated in a general dental practice. A thorough medical history should be taken and updated at every visit. A good oral examination to uncover any dental problems and possible side effects from antiepileptic drugs is necessary. Stability of the seizure disorder must be taken into account when planning dental treatment. Specific considerations for epileptic patients include the treatment of oral soft tissue side effects of medications and damage to the hard and soft tissue of the orofacial region secondary to seizure trauma. Most patients who have epilepsy can and should receive functionally and esthetically adequate dental care

Here we present a case of successful non-operative management of an iatrogenic recto-urethral fistula in a 13-year-old boy. The fistula was created when urethroscopic repair of a urethral stricture was attempted. Due to the anatomy of the lesion and previous urinary diversion, it was deemed possible to spare this patient diverting colostomy or surgical repair of the fistula. The result was successful closure of the fistula, which was confirmed on retrograde urethrogram. While we do not support the routine use of non-operative management for recto-urethral fistulas we have demonstrated that there are circumstances where it can be safely applied

Clinically, zirconia-supported all-ceramic restorations are failing by veneer-chipping without exposing the zirconia interface. We hypothesized that mouth motion step-stress-accelerated fatigue testing of standardized dental crowns would permit this previously unrecognized failure mode to be investigated. Using CAD software, we imported the average dimensions of a mandibular first molar crown and modeled tooth preparation. The CAD-based tooth preparation was rapid-prototyped as a die for fabrication of zirconia core porcelain-veneered crowns. Crowns were bonded to aged composite reproductions of the preparation and aged 14 days in water. Crowns were single-cycle-loaded to failure or mouth-motion step-stress- fatigue-tested. Finite element analysis indicated high stress levels below the load and at margins, in agreement with only single-cycle fracture origins. As hypothesized, the mouth motion sliding contact fatigue resulted in veneer chipping, reproducing clinical findings allowing for investigations into the underlying causes of such failures

This article presents details of processing, characterization and in vitro as well as in vivo evaluations of powder metallurgy processed Ti-13Nb-13Zr samples with different levels of porosity. Sintered samples were characterized for density, crystalline phases (XRD), and microstructure (SEM and EDX). Samples sintered at 1000 degrees C showed the highest porosity level ( approximately 30%), featuring open and interconnected pores ranging from 50 to 100 mum in diameter but incomplete densification. In contrast, samples sintered at 1300 and 1500 degrees C demonstrated high densification with 10% porosity level distributed in a homogeneous microstructure. The different sintering conditions used in this study demonstrated a coherent trend that is increase in temperature lead to higher sample densification, even though densification represents a drawback for bone ingrowth. Cytotoxicity tests did not reveal any toxic effects of the starting and processed materials on surviving cell percentage. After an 8-week healing period in rabbit tibias, the implants were retrieved, processed for nondecalcified histological evaluation, and then assessed by backscattered electron images (BSEI-SEM) and EDX. Bone growth into the microstructure was observed only in samples sintered at 1000 degrees C. Overall, a close relation between newly formed bone and all processed samples was observed.