Faculty Bibliography

Step-stress accelerated life testing (SSALT) and fractographic analysis were performed to evaluate the reliability and failure modes of dental implant fabricated by machining (surface treated with alumina blasting/acid etching) or laser sintering for anterior single-unit replacements. Forty-two dental implants (3.75 x 10 mm) were divided in two groups (n = 21 each): laser sintered (LS) and alumina blasting/acid etching (AB/AE). The abutments were screwed to the implants and standardized maxillary central incisor metallic crowns were cemented and subjected to SSALT in water. Use-level probability Weibull curves and reliability for a mission of 50,000 cycles at 200 N were calculated. Polarized light and scanning electron microscopes were used for failure analyses. The Beta (beta) value derived from use-level probability Weibull calculation of 1.48 for group AB/AE indicated that damage accumulation likely was an accelerating factor, whereas the beta of 0.78 for group LS indicated that load alone likely dictated the failure mechanism for this group, and that fatigue damage did not appear to accumulate. The reliability was not significantly different (p > 0.9) between AB/AE (61 %) and LS (62 %). Fracture of the abutment and fixation screw was the chief failure mode. No implant fractures were observed. No differences in reliability and fracture mode were observed between LS and AB/AE implants used for anterior single-unit crowns.

PURPOSE: To demonstrate the degree of stability decrease and subsequent increase of dental implants at early implantation times in a beagle model. MATERIALS AND METHODS: The mandibular premolars and first molars of eight beagle dogs were extracted and the ridges allowed to heal for 8 weeks. Thirty-two (n = 16 each group) implants were placed bilaterally, and remained in vivo for 1 and 3 weeks. The implants with comparable dimensions were divided as follows: group 1, Straumann Bone Level with SLActive surface; group 2, Nobel Speedy Replace RP with TiUnite surface. During insertion and following sacrifice, the implants were torqued to determine insertion and interface failure values. Histologic sections were prepared for microscopy. Statistical analysis was performed using Kruskal-Wallis and multiple paired and non-paired t tests considering unequal variances at a 95% level of significance. RESULTS: High insertion torque values were observed along with a significant decrease at 1 week in vivo (P = .003). At 3 weeks, the biomechanical fixation levels increased and were comparable to the insertion torque value. Histology showed that interfacial bone remodeling and initial woven bone formation was observed around both implant groups at 1 and 3 weeks. CONCLUSIONS: As time elapsed early after implantation, the biomechanical stability of dental implants initially decreased and subsequently increased.

Infective endocarditis is a rare but serious complication of pregnancy with high maternal and fetal mortality. Surgical intervention is an option when medical therapy fails. We report the case of a 23-year-old female with severe aortic valve regurgitation and hemodynamic compromise related to acute bacterial endocarditis of a congenital bicuspid aortic valve during the 23rd week of pregnancy. She underwent urgent aortic valve replacement and, despite implementation of known fetal-protection strategies, fetal demise occurred.

Laminin-1 has been reported as one of the factors responsible for the nucleation of calcium phosphates and, in vitro, has been reported to selectively recruit osteoprogenitors. This article focused on its in vivo effects, and evaluated the effect of laminin-1 local application on osseointegration. Polished cylindrical hydroxyapatite implants were coated with laminin-1 (test) and the bone responses in the rabbit tibiae after 2 and 4 weeks were evaluated and compared to the non-coated implants (control). Before the samples were processed for histological sectioning, they were three-dimensionally analysed with micro computed tomography (muCT). Both evaluation methods were analysed with regards to bone area around the implant and bone to implant contact. From the histologic observation, new bone formation around the laminin-1 coated implant at 2 weeks seemed to have increased the amount of supporting bone around the implant, however, at 4 weeks, the two groups presented no notable differences. The two-dimensional and three-dimensional morphometric evaluation revealed that both histologic and three-dimensional analysis showed some tendency in favour of the test group implants, however there was no statistical significance between the test and control group results.

Bone repair and regeneration are dynamic processes that involve a complex interplay between the substrate, local and systemic cells, and the milieu. Although each constituent plays an integral role in faithfully recreating the skeleton, investigators have long focused their efforts on scaffold materials and design, cytokine and hormone administration, and cell-based therapies. Only recently have the intangible aspects of the milieu received their due attention. In this review, we highlight the important influence of environmental factors on bone tissue engineering. (c) 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.

BACKGROUND: Microtia reconstruction remains one of the most challenging procedures encountered by the reconstructive surgeon. A national report on the current management of microtia has never been presented before. The purpose of this project was to survey members of the American Society of Plastic Surgeons (ASPS) to identify their preferences and practices and report their opinions regarding issues related to microtia reconstruction. METHODS: An anonymous web-based survey consisting of 19 questions was distributed to the members of the ASPS. Questions focused on the management of microtia. The study design was descriptive, using categorical data analysis. RESULTS: Thirty-eight percent of all respondents perform microtia reconstruction; 91 % learned the autogenous cartilage-based reconstruction technique, while only 16 % were exposed to alloplastic reconstruction. Seventy percent of all respondents learned autogenous cartilage-based ear reconstruction exclusively. Fifty percent of respondents who perform microtia reconstruction reported a steep learning curve. In the pediatric patient population, 49 % of microtia surgeons prefer performing the surgery when the patient is between 7 and 10 years of age, while 40 % of microtia surgeons prefer the patient to be 4-6 years of age. Fifty-nine percent of all respondents believe that in 15 years tissue engineering will represent the gold standard of microtia reconstruction. CONCLUSION: Staged microtia repair using autogenous cartilage remains the heavily favored method of microtia reconstruction among plastic surgeons. Moreover, there is a deficiency in training the newer surgical techniques, such as alloplastic and osseointegrated options. This study also highlights the continuing need to elucidate the optimal timing for microtia repair in the pediatric patient to mitigate the potential psychosocial morbidity well described in the literature. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

BACKGROUND: Many health organizations sponsor overseas surgical outreach initiatives, yet none has published a standardized protocol to prevent and manage unforeseen emergencies. Surgeons, anesthesiologists, nurses, and administrators-working together on a brief overseas humanitarian initiative-benefit from education and training to maximize their collective emergency responsiveness. This article outlines the emergency response protocol instituted by the Global Smile Foundation, a 501(c)(3) nonprofit global outreach organization providing comprehensive cleft care for the past 25 years. METHODS: The Global Smile Foundation emergency response protocol was constructed to provide all team members resources and training needed to emulate the high emergency response standards of developed nations. In this article, the authors share their education/training strategy, emergency "crash" cart inventory, site-specific safety checklist, and team member roles and responsibilities during various emergencies. RESULTS: The authors' protocol emphasizes equipment portability, location-specific adaptability, clear workflow/communication, and standardized team roles. On-site training is likewise portable, standardized, reproducible, efficient, and adaptive to each setting. These characteristics make the authors' protocol widely adoptable. CONCLUSIONS: Most morbidity and mortality during overseas surgical outreach initiatives result from unfamiliarity with the host hospital and other team members during operative (e.g., airway, bleeding, circulatory, anesthetic) or location-based (e.g., power outage, fire, oxygen shortage) emergencies. These complications are prevented and managed with aggressive team education and training. The Global Smile Foundation protocol adapts to the uncertainties of providing medical care in underresourced settings and reflects experience accumulated over the past quarter century. It is the authors' hope that other humanitarian outreach groups will adopt, customize, and build on these basic tenets.