Faculty Bibliography

The objective of this split-mouth clinical study was to compare a combination of in-office and at-home dental bleaching with at-home bleaching alone. Two applications of in-office bleaching were performed, with one appointment per week, using 38% hydrogen peroxide. At-home bleaching was performed with or without in-office bleaching using 10% carbamide peroxide in a custom-made tray every night for 2 weeks. The factor studied was the bleaching technique on two levels: Technique 1 (in-office bleaching combined with home bleaching) and Technique 2 (home bleaching only). The response variables were color change, dental sensitivity, morphology, and surface roughness. The maxillary right and left hemiarches of the participants were submitted to in-office placebo treatment and in-office bleaching, respectively (Phase 1), and at-home bleaching (Phase 2) treatment was performed on both hemiarches, characterizing a split-mouth design. Enamel surface changes and roughness were analyzed with scanning electron microscopy and optical interferometry using epoxy replicas. No statistically significant differences were observed between the bleaching techniques for either the visual or the digital analyses. There was a significant difference in dental sensitivity when both dental bleaching techniques were used, with in-office bleaching producing the highest levels of dental sensitivity after the baseline. Microscopic analysis of the morphology and roughness of the enamel surface showed no significant changes between the bleaching techniques. The two techniques produced similar results in color change, and the combination technique produced the highest levels of sensitivity. Neither technique promoted changes in morphology or surface roughness of enamel.

BACKGROUND: Approximately 20 percent of women select autologous tissue for postmastectomy breast reconstruction, and most commonly choose the abdomen as the donor site. An increasing proportion of women are seeking muscle-sparing procedures, but the benefit remains controversial. It is therefore important to determine whether better outcomes are associated with these techniques, thereby justifying longer operative times and increased costs. METHODS: Patients from five North American centers were eligible if they underwent reconstruction by means of the deep inferior epigastric artery perforator (DIEP) flap, muscle-sparing free transverse abdominis myocutaneous (TRAM) flap, free TRAM flap, or the pedicled TRAM flap. Patients were sent the BREAST-Q. Demographics and complications were collected. RESULTS: The authors analyzed 1790 charts representing 670 DIEP, 293 muscle-sparing free TRAM, 683 pedicled TRAM, and 144 free TRAM patients with an average follow-up of 5.5 years. Flap loss did not differ by flap type. Partial flap loss was higher in pedicled TRAM compared with DIEP (p = 0.002). Fat necrosis was higher in pedicled TRAM compared with DIEP and muscle-sparing free TRAM (p < 0.001). Hernia/bulge was highest in pedicled TRAM (p < 0.001). Physical well-being (abdomen) scores were higher in DIEP compared with pedicled TRAM controlling for confounders. CONCLUSIONS: Complications and patient-reported outcomes differ when comparing abdominally based breast reconstruction techniques. The results of this study show that the DIEP flap was associated with the highest abdominal well-being and the lowest abdominal morbidity compared with the pedicled TRAM flap, but did not differ from muscle-sparing free TRAM and free TRAM flaps. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Chronic hyperglycemia impairs intracellular redox homeostasis and contributes to impaired diabetic tissue regeneration. The Keap1/Nrf2 pathway is a critical regulator of the endogenous antioxidant response system and its dysfunction has been implicated in numerous pathologies. Here, we characterize the effect of chronic hyperglycemia on Nrf2 signaling within a diabetic cutaneous regeneration model. We characterized the effects of chronic hyperglycemia on the Keap1/Nrf2 pathway within models of diabetic cutaneous wound regeneration. We assessed reactive oxygen species (ROS) production and antioxidant gene expression following alterations in the Nrf2 suppressor, Keap1, and the subsequent changes in Nrf2 signaling. We also developed a topical siRNA-based therapy to restore redox homeostasis within diabetic wounds. Western blot demonstrated that chronic hyperglycemia-associated oxidative stress inhibits nuclear translocation of Nrf2 and impairs activation of antioxidant genes, thus contributing to ROS accumulation. Keap1 inhibition increased Nrf2 nuclear translocation, increased antioxidant gene expression, and reduced ROS production to normoglycemic levels, both in vitro and in vivo. Topical siKeap1 therapy resulted in improved regenerative capacity of diabetic wounds and accelerated closure. We report that chronic hyperglycemia weakens the endogenous antioxidant response and the consequences of this defect are manifested by intracellular redox dysregulation, which can be restored by Keap1 inhibition. Targeted siRNA-based therapy represents a novel, efficacious strategy to reestablish redox homeostasis and accelerate diabetic cutaneous tissue regeneration.

BACKGROUND: Despite the increasing use of nasoalveolar molding in early cleft treatment, questions remain about its effectiveness. This study examines clinician and caregiver appraisals of primary cleft lip and nasal reconstruction with and without nasoalveolar molding in a nonrandomized, prospective, multicenter study. METHODS: Participants were 110 infants with cleft lip/palate (62 treated with and 48 treated without nasoalveolar molding) and their caregivers seeking treatment at one of six high-volume cleft centers. Using the Extent of Difference Scale, standard photographs for a randomized subset of 54 infants were rated before treatment and after surgery by an expert clinician blinded to treatment group. Standard blocked and cropped photographs included frontal, basal, left, and right views of the infants. Using the same scale, caregivers rated their infants' lip, nose, and facial appearance compared with the general population of infants without clefts before treatment and after surgery. Multilevel modeling was used to model change in ratings of infants' appearance before treatment and after surgery. RESULTS: The expert clinician ratings indicated that nasoalveolar molding-treated infants had more severe clefts before treatment, yet both groups were rated equally after surgery. Nasoalveolar molding caregivers reported better postsurgery outcomes compared with no-nasoalveolar molding caregivers (p < 0.05), particularly in relation to the appearance of the nose. CONCLUSIONS: Despite having a more severe cleft before treatment, infants who underwent nasoalveolar molding were found by clinician ratings to have results comparable to those who underwent lip repair alone. Infants who underwent nasoalveolar molding were perceived by caregivers to have better treatment outcomes than those who underwent lip repair without nasoalveolar molding. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Background The internal mammary vessels are the most commonly used recipients for microsurgical breast reconstructions. Often, the costal cartilage is sacrificed to obtain improved vessel exposure. In an effort to reduce adverse effects associated with traditional rib sacrifice, recent studies have described less-invasive, rib-sparing strategies. Methods After obtaining institutional review board's approval, a retrospective review of all patients undergoing microsurgical breast reconstruction at a single institution between November 2007 and December 2013 was conducted. Patients were divided into two cohorts for comparison: rib-sacrificing and rib-sparing internal mammary vessel harvests. Results A total of 547 reconstructions (344 patients) met inclusion criteria for this study. A total of 64.9% (n = 355) underwent rib-sacrificing internal mammary vessel harvest. Cohorts were similar in baseline patient characteristics, indications for surgery, and cancer therapies. However, patients undergoing rib-sparing reconstructions had significantly shorter operative times (440 vs. 476 minutes; p < 0.01), and significantly less postoperative pain on postoperative day (POD) 1 (2.8/10 vs. 3.4/10; p = 0.033) and POD2 (2.4/10 vs. 3.0/10; p = 0.037). Furthermore, patients undergoing rib-sparing techniques had greater incidence of fat necrosis requiring excision (12.5 vs. 2.8%; p < 0.01) and a trend toward higher incidence of hematoma, venous thrombosis, and arterial thrombosis when compared with rib-sacrificing patients. Conclusions Rib-sparing harvest of internal mammary vessels is a feasible technique in microsurgical breast reconstruction. However, given the significant increase in fat necrosis requiring surgical excision, the trend toward increased postoperative complications, and no significant difference in postoperative revision rates, the purported benefits of this technique may fail to outweigh the possible risks.

BACKGROUND: Abdominal tissue is the preferred donor source for autologous breast reconstruction, but in select patients with inadequate tissue, additional volume must be recruited to achieve optimal outcomes. Stacked flaps are an effective approach in these cases, but can be limited by the need for adequate recipient vessels. This article reports outcomes for the use of the retrograde internal mammary system for stacked flap breast reconstruction in a large number of consecutive patients. METHODS: Fifty-three patients underwent stacked autologous tissue breast reconstruction with a total of 142 free flaps. Thirty patients underwent unilateral stacked deep inferior epigastric perforator (DIEP) flap reconstruction, five had unilateral stacked profunda artery perforator flap reconstruction, one had bilateral stacked DIEP/superior gluteal artery perforator flap reconstruction, and 17 underwent bilateral stacked DIEP/profunda artery perforator flap reconstruction. In all cases, the antegrade and retrograde internal mammary vessels were used for anastomoses. In situ manometry studies were also conducted comparing the retrograde internal mammary arteries in 10 patients to the corresponding systemic pressures. RESULTS: There were three total flap losses (97.9 percent flap survival rate), two partial flap losses, four reexplorations for venous congestion, and three patients with operable fat necrosis. The mean weight of the stacked flaps for each reconstructed breast was 622.8 g. The retrograde internal mammary mean arterial pressures were on average 76.6 percent of the systemic mean arterial pressures. CONCLUSIONS: The results demonstrate that the retrograde internal mammary system is capable of independently supporting free tissue transfer. These vessels provide for convenient dissection and improved efficiency of these cases, with successful postsurgical outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Surface topography modifications have become a key strategy for hastening the host-to-implant response to implantable materials. The present study evaluated the effect of three different carefully controlled surface texture patterns achieved through microrobotized blasting (controlled to high, medium and low roughness) relative to a larger scale blasting procedure (control) in early osseointegration in a canine model. Four commercially pure grade 2 titanium alloy implants (one of each surface) were bilaterally placed in the radii of six beagle dogs and allowed end points of 1 and 6 weeks in vivo. Following sacrifice, implants in bone were non-decalcified processed for bone morphologic and histometric (bone-to-implant contact; bone area fraction occupancy) evaluation. Surface topography was characterized by scanning electron microscopy and optical interferometry. Results showed initial osteogenic tissue interaction at one week and new bone in intimate contact with all implant surfaces at 6 weeks. At 1 and 6 weeks in vivo, higher bone-to-implant and bone area fraction occupancy were observed for the high texture pattern microrobotized blasted surface relative to others.