Faculty Bibliography

OBJECTIVES/OBJECTIVE:To evaluate the three-dimensional fit of abutments fabricated by the industry to those either milled or cast by a commercial laboratory and to correlate the implant-abutment connection fit with stress at fatigue failure of prostheses. Probability of survival (reliability) and fractography to characterize failure modes were also performed for cemented and screw-retained prostheses. METHODS:One-hundred and twenty-six maxillary central incisor crowns were milled to restore implants and divided in 3 cemented and 3 screwed-retained groups (n = 21/each), as follows: [Digital-Sc]: milled one-piece monolithic abutment/crown; [TiB-Sc]: milled crowns cemented onto Ti-base abutments; [UCLA]: screw-retained crown using UCLA abutments; [Digital-Ce]: milled two-piece assembly comprised by screwed monolithic abutment and a cemented crown; [TiB-Ce]: milled coping cemented onto Ti-base abutments to receive a cemented crown; [UCLA-Ce]: UCLA abutments that received an overcast coping and a cemented crown. Implant-abutment volume misfit was assessed by micro-computed tomography using the silicone replica technique. Implant/crown systems were subjected to step-stress accelerated life testing (SSALT) in water. The use-level probability Weibull curves and reliability for a mission of 50,000 cycles at calculated stress at failure of 2,300, 3300 and 4300 MPa were plotted. Fractographic analysis was performed with scanning electron microscopy. Internal misfit was analyzed through one-way ANOVA following post-hoc comparisons by Tukey test (p < 0.05). Correlation between misfit volume and the stress at fatigue failure was assessed by Pearson test. RESULTS:). The mean β values were: 1.68, 1.39, 1.48, 2.41, 2.27 and 0.71 for Digital-Sc, TiB-Sc, UCLA, Digital-Ce, TiB-Ce and UCLA-Ce, respectively, indicating that fatigue was an accelerating factor for failure of all groups. Higher stress at failure decreased the reliability of all groups, more significantly for screw compared to cement-retained groups, especially for Digital-Sc that demonstrated the lowest reliability. The failure mode was restricted to abutment screw fracture. A negative correlation was observed between misfit values and stress at failure (r = -0.302, p = 0.01). CONCLUSIONS:Abutments milled by a commercial lab presented higher misfit compared to those provided by the industry and a moderate correlation was observed between higher misfit and lower stress at failure during fatigue. Probability of survival decreased at higher stress, especially for screw compared to cement-retained groups, and failures were confined to abutment screws.

BACKGROUND:Interest in aqueous silver diamine fluoride (SDF) has been growing as a treatment for caries arrest. A cross-sectional study was conducted to identify factors associated with caregiver acceptance of SDF treatment for children presenting with caries at 8 Federally Qualified Health Centers. The study purpose was to examine associations between caregiver acceptance of SDF treatment for children with caries and (1) sociodemographic and acculturation characteristics of caregivers and (2) clinical assessments of the children by dentists. METHODS:A caregiver survey collected information on: sociodemographic characteristics; acculturation characteristics, measured using the validated Short Acculturation Scale for Hispanics (SASH); perceived benefits and barriers of SDF treatment, including caregiver comfort; and perceived health-related knowledge. Chart reviews were conducted to assess: the medical / dental insurance of pediatric patients; cumulative caries experience, measured using decayed, missing, filled teeth total scores (dmft / DMFT); whether operating room treatment was needed; and a record of caregiver acceptance of SDF treatment (the outcome measure). Standard logistic regression models were developed for caregiver acceptance of SDF treatment for their children as the binary outcome of interest (yes / no) to calculate unadjusted odds ratios (OR) and adjusted ORs for covariates of interest. RESULTS:Overall, 434 of 546 caregivers (79.5%) accepted SDF treatment for their children. A U-shaped relationship between caregiver odds of accepting SDF treatment and age group of pediatric patients was present, where caregivers were most likely to accept SDF treatment for their children who were either < 6 years or 9-14 years, and least likely to accept SDF treatment for children 6 to < 9 years. The relationship between acculturation and caregiver acceptance of SDF treatment depended upon whether or not caregivers were born in the United States: greater acculturation was associated with caregiver acceptance of SDF treatment among caregivers born in this country, and lower acculturation was associated with caregiver acceptance of SDF treatment among caregivers born elsewhere. CONCLUSIONS:Caregiver acceptance of SDF treatment is high; child's age and caregiver comfort are associated with acceptance. Providers need to communicate the risks and benefits of evidence-based dental treatments to increasingly diverse caregiver and patient populations.

OBJECTIVE/UNASSIGNED:To assess the timing, type, and associated adjunct procedures for secondary cleft rhinoplasty nationally. DESIGN/UNASSIGNED:Data were extracted from a national database of all secondary cleft rhinoplasty procedures (Current Procedural Terminology [CPT] codes 30460 and 30462). Frequency statistics were utilized to analyze demographics, comorbidities, surgical procedures, and timing. Chi-squared analysis and Fisher exact test were used for analysis. SETTING/UNASSIGNED:National Surgical Quality Improvement Program-Pediatric Database. PARTICIPANTS/UNASSIGNED:A total of 1720 patients met inclusion criteria for secondary cleft rhinoplasty repair. INTERVENTIONS/UNASSIGNED:No relevant intervention. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Age, demographics, comorbidities, and associated procedures. RESULTS/UNASSIGNED:< .001). CONCLUSIONS/UNASSIGNED:This study reveals that a large proportion of cleft rhinoplasties are performed in skeletally immature patients. Although patients undergoing rib grafting, nasal osteotomies, and a major septal component were older, these procedures are still performed in a large proportion of patients who are younger than expected.

BACKGROUND:Development of diabetic foot ulcers is a common complication of diabetes. Standard-of-care (SOC) therapy alone is often not sufficient to heal these wounds, resulting in application of adjuvant wound therapies including biologic skin substitutes. Although a variety of products exist, it has been difficult to formulate conclusions on their clinical efficacy. We therefore performed a systematic review and meta-analysis on the efficacy of healing diabetic foot ulcers with biologic skin substitutes. METHODS:A systematic review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Four electronic databases (PubMed/MEDLINE, EMBASE [Ovid], Cochrane CENTRAL [Ovid], and Web of Science) were searched from inception through February 27, 2019. Searches included keywords and subject headings pertaining to 3 main concepts: biologic skin substitutes, wound healing, and diabetic foot ulcers. Cochrane randomized controlled trial filters were used to narrow results. Data were extracted from 54 included articles, and risk-of-bias assessments were conducted by 2 independent reviewers. The primary objective was to calculate a pooled risk ratio for the proportion of wounds completely closed by 12 weeks. Secondary objectives included a pooled risk ratio for the proportion of wounds completely closed by 6 weeks and mean time to healing. RESULTS:Twenty-five studies were identified that assessed the proportion of complete wound closure by 12 weeks. We found that wounds treated with biologic dressings were 1.67 times more likely to heal by 12 weeks than those treated with SOC dressings (P < 0.00001). Five studies assessed the proportion of complete wound closure by 6 weeks. Wounds treated with biologic dressings were 2.81 times more likely to heal by 6 weeks than those treated with SOC dressings (P = 0.0001). Descriptively, 29 of 31 studies that assessed time to healing favored biologic dressings over SOC dressings. CONCLUSIONS:This systematic review provides supporting evidence that biologic skin substitutes are more effective than SOC dressings at healing diabetic foot ulcers by 12 weeks. Future studies must address the relative benefits of different skin substitutes as well as the long-term implications of these products and their financial considerations.

BACKGROUND:Cleft lip is the most common craniofacial malformation with an incidence of 1 in 700 live births. Our study sought to evaluate incidences and risk factors readmission following CLP repair using a well-validated national surgical database. METHODS:All cleft lip repairs performed between 2012 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program Pediatric Database. Patient demographics, surgical variables, and reasons for readmission were analyzed and identified. A binary logistic regression was performed to identify factors independently associated with readmission following cleft lip repair. RESULTS:The 4550 cleft lip repairs were identified with a thirty-day readmission rate of 3.8% (173 patients). A higher incidence of readmission was identified among patients with developmental delay (P ≤0.001), seizure disorder (P <0.001), structural central nervous system abnormality (P ≤0.001), steroid use within 30 days (P ≤0.001), a requirement for nutritional support (P <0.001), and ASA of 3 or higher (17.3% vs 9.9%, P <0.001). Readmitted patients were more likely to have deep incisional surgical site infections (P <0.001), deep wound dehiscence (P = 0.002), reoperation (P <0.001), pneumonia (P <0.001), and unplanned intubation (P <0.001).Multivariate regression identified seizure disorder (OR = 3.3; 95% CI = 1.3-8.3; P = 0.012) and steroid use within 30 days (OR = 3.8; 95% CI = 1.1-12.2; P = 0.030) as independently associated with readmission. The mean time of readmission was 9 days after operation. CONCLUSION/CONCLUSIONS:Patients with seizure disorder and steroid use were significantly more likely to be readmitted. Physicians should be cautious with management of patients with these risk factors.

BACKGROUND: The pectoralis major muscle flap is a versatile reconstructive option for deep sternal wound infections (DSWI). The timing and surgical technique of bilateral pectoralis major muscle advancement flaps versus unilateral pectoralis major muscle turnover and unilateral pectoralis major muscle advancement flap on patient outcomes remain to be elucidated. The purpose of this investigation was to compare timing, immediate versus delayed reconstruction, and the surgical technique in patients with deep sternal wounds infections on patient outcomes. METHODS: A retrospective review of patients who underwent sternal reconstruction with pectoralis major muscle was conducted. Patients diagnosed with DSWI after undergoing cardiac surgery were included for analysis. Patients were divided by flap timing and flap type for analyses. Bivariate tests were performed to compare patient clinical characteristics. Outcomes of interest were rates of postoperative complications, same admission mortality, reoperation, readmission, operating room time, and length of stay. RESULTS: = 0.019). CONCLUSION/CONCLUSIONS: Patients who underwent pectoralis major muscle advancement flaps had lower incidence of tissue necrosis. Furthermore, the timing of immediate sternal reconstruction was associated with a decreased hospital length of stay.

BACKGROUND: Venous outflow problems are the most common reasons for perioperative flap complications. Size mismatch in venous anastomoses poses a theoretical problem by promoting turbulent flow and subsequent thrombus formation. The purpose of this study was to determine if increased vein size mismatch is predictive of flap failure. METHODS: Retrospective review of our institutional flap registry from 1979 to 2016 identified 410 free flaps performed for reconstruction of lower extremity trauma. Patient demographics, flap characteristics, and flap outcomes were examined. Venous size mismatch was defined as a difference in size ≥ 1 mm between the recipient vein and flap vein. RESULTS: = 0.045; odds ratio: 2.58). CONCLUSION/CONCLUSIONS: Flaps with vein size mismatch ≥ 1 mm demonstrated increased flap complication rates in the setting of end-to-end venous anastomoses. End-to-side anastomosis was preferentially used in vein size mismatch and carried a higher risk of flap failure. Our results support using veins of similar size for anastomosis whenever feasible to protect against flap complications.

BACKGROUND:Human monoclonal antibodies that potently and broadly neutralise HIV-1 are under development to prevent and treat HIV-1 infection. In this phase 1 clinical trial we aimed to determine the safety, tolerability, and pharmacokinetic profile of the broadly neutralising monoclonal antibody VRC07-523LS, an engineered variant of VRC01 that targets the CD4 binding site of the HIV-1 envelope protein. METHODS:This phase 1, open-label, dose-escalation clinical trial was done at the National Institutes of Health Clinical Center in Bethesda, MD, USA. Individuals were recruited from the greater Washington, DC, area by IRB-approved written and electronic media. We enrolled healthy, HIV-1-negative adults aged 18-50 years. Inclusion criteria were good general health, measured through clinical laboratory tests, medical history, and physical examination. Participants self-selected into one of seven open groups during enrolment without randomisation. Four groups received a single intravenous dose of 1, 5, 20, or 40 mg/kg of VRC07-523LS, and one group received a single 5 mg/kg subcutaneous dose. Two groups received three doses of either 20 mg/kg intravenous VRC07-523LS, or 5 mg/kg subcutaneous VRC07-523LS at 12-week intervals. The primary outcome was the safety and tolerability of VRC07-523LS, assessed by dose, route, and number of administrations. This study is registered with ClinicalTrials.gov, NCT03015181. FINDINGS/RESULTS:Between Feb 21, 2017, and September 13, 2017, we enrolled 26 participants, including 11 (42%) men and 15 (58%) women. Two (8%) participants withdrew from the study early: one participant in group 1 enrolled in the study but never received VRC07-523LS, and one participant in group 6 chose to withdraw after a single administration. One (4%) participant in group 7 received only one of the three scheduled administrations. 17 participants received intravenous administrations and 8 participants received subcutaneous administrations. VRC07-523LS was safe and well tolerated, we observed no serious adverse events or dose-limiting toxic effects. All reported local and systemic reactogenicity was mild to moderate in severity. The most commonly reported symptoms following intravenous administration were malaise or myalgia in three (18%) participants and headache or chills in two (12%) participants. The most commonly reported symptoms following subcutaneous administration were pain and tenderness in four participants (50%) and malaise or headache in three (38%) participants. INTERPRETATION/CONCLUSIONS:Safe and well tolerated, VRC07-523LS is a strong and practical candidate for inclusion in HIV-1 prevention and therapeutic strategies. The results from this trial also indicate that an HIV-1 broadly neutralising monoclonal antibody engineered for improved pharmacokinetic and neutralisation properties can be safe for clinical use. FUNDING/BACKGROUND:National Institutes of Health.

BACKGROUND:Biofilms represent a complex milieu of matrix-enclosed microorganisms, which can significantly contribute to the pathology of chronic wounds. In this study, we compare the activity of 3 commercial antimicrobial wound care solutions, Vashe (HOCl based), PhaseOne (HOCl based), and Sulfamylon (mafenide acetate), for their in vitro activity against bacterial and fungal biofilms. METHODS:Reference and clinical isolates of 6 Gram-negative bacterial species (36 total strains), 3 Gram-positive bacteria (21 strains), and 3 Candida species (9 strains) were used to create biofilms. Various working concentrations of the 3 antiseptic agents were incubated with the biofilms in microwell plates; they were monitored from 1 minute to 24 hours to compare bacterial and fungal viability through colony forming unit analysis. RESULTS:Vashe and PhaseOne displayed excellent bactericidal and fungicidal activity, whereas Sulfamylon demonstrated minimal activity against the biofilms tested. With the exception of Candida albicans, all biofilms were eliminated at either 1 or 10 minutes using Vashe and PhaseOne solutions. In most cases, mafenide was unable to eliminate both bacterial and fungal biofilms, even with 24 hours of treatment. CONCLUSIONS:Biofilms represent a major clinical challenge, with no clear consensus for treatment of chronic wounds or prosthetic devices. Our results suggest that hypochlorous acid-based wound solutions such as Vashe and PhaseOne are more efficacious than mafenide in eliminating bacterial and fungal biofilms. Further studies are necessary to investigate and compare the in vivo efficacy of these products in clinical care.

This paper is aimed to present a biomaterials perspective in implant therapy that fosters improved bone response and long-term biomechanical competence from surgical instrumentation to final prosthetic rehabilitation. Strategies to develop implant surface texturing will be presented and their role as an ad hoc treatment discussed in light of the interplay between surgical instrumentation and implant macrogeometric configuration. Evidence from human retrieved implants in service for several years and from in vivo studies will be used to show how the interplay between surgical instrumentation and implant macrogeometry design affect osseointegration healing pathways, and bone morphologic and long-term mechanical properties. Also, the planning of implant-supported prosthetic rehabilitations targeted at long-term performance will be appraised from a standpoint where personal preferences (eg, cementing or screwing a prosthesis) can very often fail to deliver the best patient care. Lastly, the acknowledgement that every rehabilitation will have its strength degraded over time once in function will be highlighted, since the potential occurrence of even minor failures is rarely presented to patients prior to treatment.