Faculty Bibliography

PURPOSE: This study evaluated the effect of the platform-switching phenomenon, the use of a smaller diameter abutment on a larger diameter implant platform. Clinical and histological outcomes of the periimplant mucosa around titanium abutments in a nonsubmerged implant were evaluated. MATERIALS AND METHODS: Ten healthy adult patients, ranging from 27 to 65 years, participated in the study. A minimum of 2 endosseous implants with immediate abutment connection was placed per patient, 1 conventional and 1 platform-switched abutment. All sites for implant placement had an adequate zone of keratinized mucosa before surgical intervention. RESULTS: No clinical signs of inflammation were observed in the periimplant soft tissue mucosa, and healing was uneventful throughout the study period. Histological findings showed abnormally thick stratified squamous epithelium for both groups with few inflammatory cells in the connective tissue and none on the surface of the epithelium. CONCLUSION: Histological findings for both conventional and platform-switched implant-abutment configurations showed a similar composition of the soft tissue. These findings were in direct agreement with previous studies.

BACKGROUND: Fat grafting is limited by unpredictable long-term graft retention. The authors postulate that injury to the donor-derived microvasculature during harvest and subsequent ischemia may account for this clinical variability. They examined the use of the U.S. Food and Drug Administration-approved phosphodiesterase-5 inhibitor sildenafil citrate to protect graft microvasculature and its role in revascularization and survival. METHODS: Inguinal fat of donor Tie2/LacZ mice was infiltrated with sildenafil or saline, harvested, and transplanted onto the dorsa of recipient FVB mice. Additional donor mice were perfused with intraarterial trypsin to inactivate the fat graft microvasculature before harvest and transplantation. Differences in graft revascularization, perfusion, volume of retention, and biochemical changes were assessed. RESULTS: Surviving fat grafts were characterized by exclusively donor-derived vasculature inosculating with the recipient circulation at the graft periphery. Inactivation of donor-derived microvasculature decreased early graft perfusion and led to nearly total graft loss by 8 weeks. Sildenafil attenuated vascular ischemic injury, consistent with reductions in VCAM-1 and SDF1alpha expression at 48 hours and 4-fold increases in microvasculature survival by 2 weeks over controls. Compared with controls, targeted sildenafil treatment improved early graft perfusion, doubled graft retention at 12 weeks (83 percent versus 39 percent; p < 0.05), ultimately retaining 64 percent of the original graft volume by 24 weeks (compared to 4 percent; p < 0.05) with superior histologic features. CONCLUSIONS: Fat graft vascularization is critically dependent on maintenance of the donor microvasculature. Sildenafil protects the donor microvasculature during transfer and revascularization, increasing long-term volume retention. These data demonstrate a rapidly translatable method of increasing predictability and durability of fat grafting in clinical practice.

INTRODUCTION: To evaluate the influence of storage time on the elastic modulus, micromorphology, nanoleakage, and micromechanical behavior of the dentin-adhesive interfaces of five adhesive systems (Scotchbond Multi-Purpose, Clearfil SE Bond, One Up Bond F, Adper Easy One, and Filtek LS Adhesive) after 24h (T0) and 12 months (T1). METHODS: Fifty teeth were restored and distributed according to each adhesive system (n=10). At least four specimens were obtained from each tooth. One specimen was evaluated under SEM to obtain the micromorphology of dentin-adhesive interface (DAI). Two specimens were used to assess nanoleakage, one tested in T0 and the other in T1. The last specimen was used for nanoindentation, in T0 and T1, to obtain the initial and final mechanical properties of DAI structures. Two non-restored teeth were evaluated under SEM to obtain the dentin morphology. Laboratorial data were used to build 15 finite element models to assess the maximum principal stress in each time of analysis. RESULTS: Storage resulted in hydrolysis of the dentin-adhesive interfaces for all groups. Silver impregnation increased for all groups after 1 year storage (p<.05), except for Clearfil SE Bond. In general, a decrease in elastic modulus values was observed for all groups from T0 to T1 (p<.05), mainly at the hybrid layer. The FEAs showed higher stress levels at T1 than T0 simulations for all adhesives. CONCLUSION: At T1, degradation occurred at the dentin-adhesive interface formed by all adhesives, and the intensity of degradation differed depending on the type of adhesive system used. The interface formed by the self-etching primer containing the 10-MDP functional monomer showed the highest stability among the adhesive systems after 12 months of storage.

Sutures elicit an inflammatory response, which may impede the healing process and result in wound complications. We recently reported a novel family of biocompatible, biodegradable polymers, amino acid-based poly(ester amide)s (AA-PEA), which we have shown to significantly attenuate the foreign body inflammatory response in vitro. Two types of AA-PEA (Phe-PEA and Arg-Phe-PEA) were used to coat silk or plain-gut sutures, which were implanted in the gluteus muscle of C57BL/6 mice, while the uncoated control sutures were implanted in the contralateral side. After 3, 7, 14, and 28 days the mean area of inflammation surrounding the sutures was compared. Phe-PEA coating of silk sutures significantly decreased inflammation compared with noncoated controls (67.8 +/- 17.4% after 3d [p = 0.0014], 51.6 +/- 7.2% after 7d [p < 0.001], and 37.3 +/- 8.3% after 28d [p = 0.0001]) when assessed via analysis of photomicrographs using digital image software. Phe-PEA coated plain-gut sutures were similarly assessed and demonstrated a significant decrease in the mean area of inflammation across all time points (54.1 +/- 8.3% after 3 d, 41.4 +/- 3.9% after 7 d, 71.5 +/- 8.1% after 14 d, 78.4 +/- 8.5%, and after 28 d [all p < 0.0001]). Arg-Phe-PEA coated silk demonstrated significantly less inflammation compared to noncoated controls (61.3 +/- 9.4% after 3 d, 44.7 +/- 4.7% after 7 d, 19.6 +/- 8%, and 38.3 +/- 6.8% after 28 d [all p < 0.0001]), as did coated plain-gut (37.4 +/- 8.3% after 3 d [p = 0.0004], 55.0 +/- 7.8% after 7 d [p < 0.0001], 46.0 +/- 4.6% after 14 d [p < 0.0001], and 59.0 +/- 7.9% after 28 d [p < 0.0001]). Both Phe-PEA and Arg-Phe-PEA coatings significantly decrease the inflammatory response to sutures in vivo for up to 28 days.

BACKGROUND: Outcome studies of immediate implant-based breast reconstruction have focused largely on patient factors, whereas the relative impact of the surgeon as a contributing variable is not known. As the procedure requires collaboration of both a surgical oncologist and a plastic surgeon, the effect of the surgeon team interaction can have a significant impact on outcome. This study examines outcomes in implant-based breast reconstruction and the association with patient characteristics, surgeon, and surgeon team familiarity. METHODS: A retrospective review of 3142 consecutive implant-based breast reconstruction mastectomy procedures at one institution was performed. Infection and skin necrosis rates were measured. Predictors of outcomes were identified by unadjusted logistic regression followed by multivariate logistic regression. Surgeon teams were grouped according to number of cases performed together. RESULTS: Patient characteristics remain the most important predictors for outcomes in implant-based breast reconstruction, with odds ratios above those of surgeon variables. The authors observed significant differences in the rate of skin necrosis between surgical oncologists with an approximately two-fold difference between surgeons with the highest and lowest rates. Surgeon teams that worked together on fewer than 150 procedures had higher rates of infection. CONCLUSIONS: Patient characteristics are the most important predictors for surgical outcomes in implant-based breast reconstruction, but surgeons and surgeon teams are also important variables. High-volume surgeon teams achieve lower rates of infection. This study highlights the need to examine modifiable risk factors associated with optimum implant-based breast reconstruction outcomes, which include patient and provider characteristics and the surgical team treating the patient. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Background Tracheobronchopathia osteochondroplastica is a rare benign and often indolent disease. We report the first case of tracheobronchopathia osteochondroplastica (TBO) presenting as acute hypercarbic respiratory failure due to superimposed subglottic submucosal abscess. Case Report A 27-year-old man presented to the emergency department in respiratory distress that required mechanical ventilation for acute hypercarbic respiratory failure. Upon extubation the next day, stridor was elicited with ambulation. Spirometry revealed fixed upper airway obstruction. Neck imaging showed a 2.8x2.0x4.0 cm partially calcified subglottic mass with cystic and solid component obstructing 75% of the airway. Surgical exploration revealed purulent drainage upon elevation of the thyroid isthmus and an anterolateral cricoid wall defect in communication with a subglottic submucosal cavity. Microbiology was negative for bacteria or fungi. Pathology showed chondro-osseous metaplasia compatible with tracheobronchopathia osteochondroplastica (TBO). The patient received a course of antibiotics and prophylactic tracheostomy. Since tracheostomy removal 3 days later, the patient remains asymptomatic. Conclusions Tracheobronchopathia osteochondroplastica is a rare disease with usually benign clinical course and incidental diagnosis. It may present as acute hypercarbic respiratory failure when subglottic infection is superimposed.

Introduction: Cleanliness of the canal space is the ultimate goal of its preparation. Nevertheless, some portion of the canal walls are left un-instrumented during preparation. Therefore, the aim of this ex vivo study was to evaluate the cleanliness of un-instrumented canal walls after root canal preparation for the presence or absence of debris and smear layer. Materials and Methods: A total of 24 single-rooted extracted teeth were prepared with the crown-down technique using Protaper universal rotary file system. Micro-computed tomography (micro-CT) was used to scan the specimens before and after instrumentation. The un-instrumented area was measured and localized. The roots were split longitudinally and then subjected to scanning electron microscopy (SEM). The presence of debris and smear layer in the instrumented and un-instrumented areas of the canal were evaluated by analysing the SEM images with a five-score evaluation system based on the reference photographs. Results: High levels of root canal cleanliness (= score 2) were found for the instrumented areas were detected (P = 0.003). Conclusions: Under the condition of this study, un-instrumented areas of the canal were less clean in comparison to instrumented portion.

BACKGROUND: Practitioners who are not board-certified by the American Board of Plastic Surgery are practicing cosmetic surgery. The extent of this issue across the United States has yet to be examined in detail. METHODS: A systematic search using Google was performed to evaluate the qualifications of clinicians marketing themselves as plastic surgeons. For every U.S. state, the following searches were performed: [state] plastic surgery, [state] cosmetic surgery, and [state] aesthetic surgery. The first 50 Web sites returned for each search were visited and scrutinized using the American Society of Plastic Surgeons and American Board of Plastic Surgery Web sites. RESULTS: In total, 7500 Web sites were visited, yielding 2396 board-certified plastic surgeons (77.9 percent of all practitioners). There were 284 board-certified ear, nose, and throat surgeons, 61 (21.5 percent) of whom practice outside their scope; 106 board-certified general surgeons, 100 (94.3 percent) of whom practice outside their scope; 104 board-certified oral and maxillofacial surgery surgeons, 68 (65.4 percent) of whom practice outside their scope; 70 board-certified ophthalmologists/oculoplastic surgeons, 49 (70 percent) of whom practice outside their scope; and 74 board-certified dermatologists, 36 (48.6 percent) of whom practice outside their scope. There were also 16 internal medicine doctors, 13 obstetrics and gynecology physicians, six emergency medicine physicians, three pediatricians, two urologists, two anesthesiologists, and finally one phlebotomist; all of these practitioners practice outside their scope as defined by Accreditation Council for Graduate Medical Education core competencies. CONCLUSIONS: Many clinicians performing cosmetic surgery are not board-certified. This finding has important implications for patient safety.