Faculty Bibliography

Objectives: This preliminary investigation aimed to evaluate the potential of contaminated implants to reosseointegrate into pristine sites and, in addition, to assess the potential of osseointegration of new implants in peri-implantitis sockets in a canine model. Methods: All mandibular premolars were bilaterally extracted from two mongrel dogs. Following 12 weeks of healing, two dental implants were inserted on each hemiarch. Forty-five days following implant placement, a silk ligature secured with cyanoacrylate was placed around the implants' cervical region in order to induce peri-implantitis. After another 45 days from ligature placement, the implants were mechanically removed using counter rotation with a ratchet and were reimplanted without any decontamination (neither rinsing nor chemical or mechanical cleaning) in adjacent pristine zones. In sites where implants were removed, new, wider-diameter implants were placed in the infected sockets. Forty-five days following reimplantation surgery, the dogs were sacrificed; nondecalcified specimens were processed and toluidine blue stained for morphologic and morphometric (bone-to-implant contact [BIC]) assessment under an optical microscope. Results: In dog 1 all the implants (both in the pristine and in the infected sites) survived and osseointegrated while in dog 2, six out of eight implants failed to osseointegrate and exfoliated. Overall, the mean BIC of all implants was 51.08% (SD 20.54). The mean BIC for the infected implants placed into pristine sites was 51.48% +/- 26.29% (SD) and the mean BIC for the new implants in peri-implantitis socket was 50.58% +/- 14.27% (SD). Conclusions: Within the limitations of this preliminary investigation, especially the small number of animals, osseointegration seems to be achievable both in infected sites and around contaminated implant surfaces.

PURPOSE: This report summarizes our experience in the management of extratemporal facial paralysis with a variety of reconstructive techniques and explores those parameters which are considered to be useful in achieving better outcomes. METHODS: In all, 56 patients with extratemporal facial paralysis were studied. All the patients had a mean follow-up of 5 years (standard deviation: 3.5). Video evaluation was performed by 3 independent assessors at the required follow-up intervals. RESULTS: The final median score for the partial facial paralysis group was significantly higher (4.175) compared with the complete facial paralysis (3.3), P = 0.007. In this series, the only other factor that appeared to influence the final outcome was the denervation time and not the age group, type of facial nerve injury, or method of repair. CONCLUSION: The concept of dynamic panfacial reconstruction with an individual and tailored to patient's needs approach is demonstrated in all and particularly in bilateral cases.

BACKGROUND: The anatomy of the facial nerve and its branches has been well documented. The course of the extratemporal facial nerve, its anatomical planes, and the surface landmarks of the temporal division and marginal mandibular division are well known. However, the surface landmark of the middle division of the facial nerve has not been studied to date. METHODS: Eighteen hemifacial dissections in 10 fresh human cadavers were performed through a preauricular face-lift incision. An 18-gauge needle with brilliant green dye was used to mark the nerve through the skin before dissection. The exact location of the middle division branches of the facial nerve was documented in relation to the transcutaneous marking. RESULTS: The middle division branches of the facial nerve were found to lie at a mean of 2.3 mm from the tattooed point, with a range of 0 to 6 mm. A nerve branch was found directly tattooed by the needle seven of 18 times, inferior to the tattoo five of 18 times, and superior to the tattoo six of 18 times. CONCLUSIONS: The zygomatic/buccal motor branch that innervates the zygomaticus major muscle can be reliably found at the midway point on a line drawn from the root of the helix and the lateral commissure of the mouth. This study will help guide surgeons to the middle division of the facial nerve as it applies to facial surgery.

BACKGROUND: : Fat grafting has emerged as a useful method for breast contouring in aesthetic and reconstructive patients. Advancements have been made in fat graft harvest and delivery, but the ability to judge the overall success of fat grafting remains limited. The authors applied three-dimensional imaging technology to assess volumetric fat graft survival following autologous fat transfer to the breast. METHODS: : Fat grafting surgery was performed using a modified Coleman technique in breast reconstruction. Patients undergoing the procedure were entered into the study prospectively and followed. Three-dimensional imaging was performed using the Canfield Vectra system and analyzed using Geomagic software. Breasts were isolated as closed objects, and total breast volume was calculated on every scan. RESULTS: : The data stratified patients into three groups with statistically significant parameters based on the volume of fat injected. The largest injected group (average volume, 151 cc) retained a volume of 86.9 percent (7 days postoperatively), 81.1 percent (16 days), 57.5 percent (49 days), and 52.3 percent (140 days). The smallest group (average, 51 cc) retained a volume of 87.9 percent (7 days postoperatively), 75.8 percent (16 days), 56.6 percent (49 days), and 27.1 percent (140 days). The intermediate group (average, 93 cc) retained 90.3 percent (7 days postoperatively), 74 percent (16 days), 45.7 percent (49 days), and 38.1 percent (140 days). Of note, irradiation or prior breast procedure type did not seem to affect the volume retention rate. CONCLUSIONS: : The authors' data suggest that fat retention is volume and time dependent. Patients receiving higher volumes of injected fat had slower volume loss and greater total volume retention.

PURPOSE: The present study evaluated the effect of different drilling dimensions (undersized, regular, and oversized) in the insertion and removal torques of dental implants in a beagle dog model. METHODS: Six beagle dogs were acquired and subjected to bilateral surgeries in the radii 1 and 3 weeks before euthanasia. During surgery, 3 implants, 4 mm in diameter by 10 mm in length, were placed in bone sites drilled to 3.2 mm, 3.5 mm, and 3.8 mm in final diameter. The insertion and removal torque was recorded for all samples. Statistical analysis was performed by paired t tests for repeated measures and by t tests assuming unequal variances (all at the 95% level of significance). RESULTS: Overall, the insertion torque and removal torque levels obtained were inversely proportional to the drilling dimension, with a significant difference detected between the 3.2 mm and 3.5 mm relative to the 3.8 mm groups (P < 0.03). Although insertion torque-removal torque paired observations was statistically maintained for the 3.5 mm and 3.8 mm groups, a significant decrease in removal torque values relative to insertion torque levels was observed for the 3.2 mm group. A different pattern of healing and interfacial remodeling was observed for the different groups. CONCLUSIONS: Different drilling dimensions resulted in variations in insertion torque values (primary stability) and stability maintenance over the first weeks of bone healing.

BACKGROUND: Reconstructing periorbital defects is challenging because of the simultaneous need for ocular support, corneal protection, and restoration of aesthetic subtleties. In patients with extensive periorbital tissue loss, microvascular free tissue transfer is a reliable reconstructive option for composite defects. METHODS: The authors conducted a retrospective review of patients with periorbital craniofacial defects and identified those treated with microvascular reconstruction at the R Adams Cowley Shock Trauma Center and The Johns Hopkins Hospital from 2001 to 2010. RESULTS: Twenty-four patients underwent free flap reconstruction for periorbital defects secondary to trauma (n = 12), oncologic resection (n = 11), and congenital deformity (n = 1). The majority were men (n = 13), and the average age of the patients was 47 years (range, 19 to 80 years). Microvascular reconstructions included fibula (n = 9), anterolateral thigh (n = 6), ulnar forearm (n = 7), and groin flaps (n = 2). Flap survival rate was 100 percent, with an average follow-up of 26.5 months. CONCLUSIONS: Microvascular reconstruction of the periorbit can be accomplished successfully through careful analysis of tissue loss, eye or ocular prosthetic support, donor-site morbidity, and patient preference. Despite the multiple flap options that fulfill periorbital reconstructive needs, the authors find that the fibula, anterolateral thigh, ulnar forearm, and groin flaps can be used reliably to successfully reconstruct these defects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

OBJECTIVES: This study evaluated the effect of implant surface blasting variables, such as blasting media size, velocity, and surface coverage and their two- and three-way interaction in surface roughness parameters. MATERIAL AND METHODS: Machined, grade IV titanium-alloy implants (n = 180) had their surfaces treated by a combination of 36 different blasting protocols according to the following variables: aluminum oxide blasting media particle size (50, 100, and 150 mum); velocity (75, 100, 125, and 150 m/s), and surface coverage (5, 15, 25 g/in.(2) ) (n = 5 per blasting protocol). A single 0.46 inch nozzle of the blaster was pointed at the threaded area and spaced 0.050 inches away. Surface topography (n = 5 measurements per implant) was assessed by scanning electron microscopy. Roughness parameters Sa, Sq, Sdr, and Sds were evaluated by optical interferometry. A GLM statistical model evaluated the effects of blasting variables on the surface parameters, and their two- and three-way interaction (P < 0.05). Statistical inferences for Sa and Sq were performed after a log(10) transformation to correct for data skewness. RESULTS: Prior to the log(10) transformation, Sa and Sq values for all processing groups ranged from ~0.5 to ~2.6 mum and from ~0.75 to 4 mum, respectively. Statistical inferences showed that Sa, Sq, and Sdr values were significantly dependent on blasting media, velocity, and surface coverage (all P < 0.001). Media x velocity, media x coverage, and media x velocity x coverage also significantly affected Sa, Sq, and Sdr values (P < 0.002). The highest levels were obtained with 100 mum blasting media, coverage for 5 g/in.(2) , and velocity of 100 m/s. No significant differences were observed for Sds (P > 0.15). CONCLUSIONS: The blasting variables produced different surface topography features and knowledge of their interaction could be used to tailor a desired implant surface configuration.

OBJECTIVES: This study evaluated the reliability and failure modes of implants with a microthreaded or smooth design at the crestal region, restored with screwed or cemented crowns. The postulated null hypothesis was that the presence of microthreads in the implant cervical region would not result in different reliability and strength to failure than smooth design, regardless of fixation method, when subjected to step-stress accelerated life-testing (SSALT) in water. MATERIALS AND METHODS: Eighty four dental implants (3.3 x 10 mm) were divided into four groups (n = 21) according to implant macrogeometric design at the crestal region and crown fixation method: Microthreads Screwed (MS); Smooth Screwed (SS); Microthreads Cemented (MC), and Smooth Cemented (SC). The abutments were torqued to the implants and standardized maxillary central incisor metallic crowns were cemented (MC, SC) or screwed (MS, SS) and subjected to SSALT in water. The probability of failure versus cycles (90% two-sided confidence intervals) was calculated and plotted using a power law relationship for damage accumulation. Reliability for a mission of 50,000 cycles at 150 N (90% 2-sided confidence intervals) was calculated. Differences between final failure loads during fatigue for each group were assessed by Kruskal-Wallis along with Benferroni's post hoc tests. Polarized-light and scanning electron microscopes were used for failure analyses. RESULTS: The Beta (beta) value (confidence interval range) derived from use level probability Weibull calculation of 1.30 (0.76-2.22), 1.17 (0.70-1.96), 1.12 (0.71-1.76), and 0.52 (0.30-0.89) for groups MC, SC, MS, and SS respectively, indicated that fatigue was an accelerating factor for all groups, except for SS. The calculated reliability was higher for SC (99%) compared to MC (87%). No difference was observed between screwed restorations (

BACKGROUND: The central face high-energy avulsive injury has been frequently encountered and predictably managed at the R Adams Cowley Shock Trauma Center. However, despite significant surgical advances and multiple surgical procedures, the ultimate outcome continues to reveal an inanimate, insensate, and suboptimal aesthetic result. METHODS: To effectively address this challenging deformity, a comprehensive multidisciplinary approach was devised. The strategy involved the foundation of a basic science laboratory, the cultivation of a supportive institutional clinical environment, the innovative application of technologies, cadaveric simulations, a real-time clinical rehearsal, and an informed and willing recipient who had the characteristic deformity. RESULTS: After institutional review board and organ procurement organization approval, a total face, double jaw, and tongue transplantation was performed on a 37-year-old man with a central face high-energy avulsive ballistic injury. CONCLUSIONS: This facial transplant represents the most comprehensive transplant performed to date. Through a systematic approach and clinical adherence to fundamental principles of aesthetic surgery, craniofacial surgery, and microsurgery and the innovative application of technologies, restoration of human appearance and function for individuals with a devastating composite disfigurement is now a reality. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Pancreatic adenocarcinoma is one of the deadliest human malignancies with the majority of cases diagnosed late in the course of the disease. Cutaneous metastases originating from pancreatic cancer are rare. The most common site reported is the umbilicus. Non-umbilical cutaneous metastases are far less common with only a few cases reported in the literature. Our case involved a 43-year-old man with pancreatic carcinoma who was offered resection and a Whipple procedure was planned. Intraoperatively, the patient was found to have a widely metastatic disease not seen on preoperative imaging. Postoperatively, cutaneous metastasis in the scalp was discovered. Although rare, the recognition of non-umbilical cutaneous metastases of pancreatic adenocarcinoma can be of value because they can not only detect an underlying tumour but also guide management.