Faculty Bibliography

BACKGROUND: : Patients with syndromic craniosynostosis and midface hypoplasia are often treated with Le Fort III advancement. The authors present four patients with extraordinarily long-term follow-up (in excess of 20 years). METHODS: : An institutional review board-approved retrospective chart review was performed on all patients with syndromic craniofacial synostosis who underwent Le Fort III advancement. Patients with greater than 20 years of cephalometric and photographic records were identified. Lateral cephalograms were obtained preoperatively, immediately postoperatively, at 1-year follow-up, and at long-term follow-up. Cephalograms were traced, digitized, and averaged. Fifty cephalometric landmarks were identified for serial measurements. RESULTS: : Of the four patients identified, one had Apert syndrome and three had Crouzon syndrome. Average age at the time of Le Fort III advancements was 11 years (range, 4 to 20 years). Average length of postoperative follow-up was 25 years (+/-5 years). No patient had significant anterior midfacial growth following Le Fort III advancement. Both young patients (<10 years) had substantial vertical inferior midfacial growth after advancement. CONCLUSIONS: : These data demonstrate that the Le Fort III segment of children with syndromic craniosynostosis does not grow significantly forward. Moreover, the traditional Le Fort III osteotomy does not provide the amount of midface advancement necessary to avoid phenotypic recidivism in these syndromic patients. This study also suggests that patients undergoing Le Fort III advancement appear to have zygomatic effacement and ptosis of the overlying soft tissue with deepening of the facial folds; collectively, it is suggested that these changes give the appearance of accelerated facial aging. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, V

Oral Diseases (2011) doi: 10.1111/j.1601-0825.2011.01848.x Objective: Oral infection is considered to play a critical role in the pathogenesis of bisphosphonate-related osteonecrosis of the jaw (BRONJ), and antibiotic therapy has become a mainstay of BRONJ therapy. This study was aimed to investigate the effect of antibiotics on bacterial diversity in BRONJ tissues. Materials and methods: The bacterial profile from soft tissues associated with the BRONJ lesion was determined using 16S rRNA-based denaturing gradient gel electrophoresis (DGGE) and sequencing. Twenty BRONJ subjects classified as stage 0-2 were enrolled in this study, and patient groups were divided into an antibiotic cohort (n = 10) treated with systemic antibiotic and a non-antibiotic cohort (n = 10) with no prior antibiotic therapy. Results: The DGGE fingerprints indicated no significant differences in bacterial diversity of BRONJ tissue samples. Patients on antibiotics had higher relative abundance of phylum Firmicutes with bacterial species, Streptococcus intermedius, Lactobacillus gasseri, Mogibacterium timidum, and Solobacterium moorei, whereas patients without antibiotics had greater amounts of Parvimonas micra and Streptococcus anginosus. Thirty percent of bacterial populations were uncultured (yet-to be cultured) phylotypes. Conclusion: This study using limited sample size indicated that oral antibiotic therapy may have a limited efficacy on the bacterial population associated with BRONJ lesions

ABSTRACT: There is tremendous interest in autologous fat grafting for the management of soft tissue volume deficiencies, treatment of cutaneous injuries, and regeneration of missing parts. Given its relative abundance and proximity to the surface of the skin, adipose tissue seems an excellent choice for the treatment of both congenital and acquired soft tissue defects, but the mesenchymal stem cells contained within the fat may provide unexpected opportunities for tissue replacement and repair. Although adipose transfer has been successfully used for reconstructive purposes since the end of the 19th century, numerous controversies about adipose harvesting, processing, delivery, survival, and efficacy still persist today. The purpose of this article was to highlight current practices, areas of controversy, and near-term future applications of fat grafting for reconstruction of the face.

OBJECTIVE: Catheter-related infection remains a cause of morbidity in the use of external ventricular drains (EVDs). The aim of this retrospective single-center study was to assess the rate and factors related to ventriculostomy infections in the setting of the published literature. METHODS: Patients that underwent EVD placement in a single-center were retrospectively reviewed. Diagnosis, treatment, hospital course, and infection-related data were collected and analyzed in reference to ventriculitis rates. The protocols for EVD placement and maintenance were reviewed. RESULTS: Of 343 patients, 12 acquired an EVD infection. No significant differences existed between those with and without ventriculitis for age, sex, underlying diagnosis, or concomitant systemic infection. Although not significant, concomitant systemic infection existed in 4.7% of patients with ventriculitis versus 1.5% without. There was a significant difference in length of EVD placement in patients with ventriculitis (20.9 +/- 15.3 days) versus those without (12.1 +/- 18.2; P = 0.005). Coagulase-negative Staphylococcus and Staphylococcus aureus represented the most commonly associated pathogens. With an overall cumulative incidence of 3.5%, our rate compared favorably to the published literature (cumulative incidence 9.5%; range, 3.9%-23.2%). CONCLUSIONS: Catheter-related infection remains an important complication of EVD placement. Of factors evaluated, length of time of catheter placement has the most notable relationship to infection incidence, suggesting that early drain removal should be a goal whenever medically appropriate.

BACKGROUND:Preoperative lymphoscintigraphy for sentinel node biopsy (SNB) combined with intra-operative gamma-probe detection often identifies nodes within the pelvis. This study investigates the role of pelvic SNB harvest. METHODS:Retrospective review of eighty-two stage I/II melanoma patients with primary tumour on the lower limb and trunk who underwent groin SNB, either inguinal or pelvic or both, over a three year period. RESULTS:Of the 82 patients, 19 had positive SNBs (24%), all of which were inguinal nodes. None of the 11 patients with pelvic nodes removed had a positive pelvic node. The median follow-up period was 18 months (SD: 10.8; range: 8-43). Although the complication rate was higher following pelvic SNB, the difference was not statistically significant (p > 0.5). The average operative time for an inguinal SNB was 92 min, and increased significantly to 134 min for a pelvic SNB (p < 0.0001). Lymphoscintigraphy of trunk and thigh melanomas identified individual tracks to be leading directly from the tumour to a pelvic node(s). However, when the primary tumour was located at or below the knee, pelvic nodes identified by lymphoscintigraphy appeared to be second level nodes. CONCLUSION/CONCLUSIONS:A lymphoscintigraphy protocol that includes dynamic images obtained in frequent intervals following injection of the radiotracer combined with thorough preoperative analysis of the lymphoscintigraphy scans and effective communication between the radiologist and the surgeon allows accurate identification of the primary tracks and prevent unnecessary harvest of second echelon pelvic lymph nodes. In patients with significant co-morbidities due consideration is required before harvesting pelvic sentinel nodes.

PURPOSE: Primary stability has been regarded as a key factor to ensure uneventful osseointegration of dental implants. Such stability is often achieved by placing implants in undersized drilled bone. The present study evaluated the effect of drilling dimensions in insertion torque and early implant osseointegration stages in a beagle dog model. MATERIALS AND METHODS: Six beagle dogs were acquired and subjected to bilateral surgeries in the radii 1 and 3 weeks before death. 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 diameter. The insertion torque was recorded for all samples. After death, the implants in bone were nondecalcified processed and morphologically and morphometrically (bone-to-implant contact and bone area fraction occupancy) evaluated. Statistical analyses were performed using the Kruskal-Wallis test followed by Dunn's post hoc test for multiple comparisons at the 95% level of significance. RESULTS: The insertion torque levels obtained were inversely proportional to the drilling dimension, with a significant difference detected between the 3.2-mm and 3.8-mm groups (P = .003). Despite a significant increase in the bone-to-implant contact over time in vivo for all groups (P = .007), no effect for the drilling dimension was observed. Additionally, no effect of the drilling dimension and time was observed for the bone area fraction occupancy parameter (P = .31). The initial healing pathways differed between implants placed in bone drilled to different dimensions. CONCLUSIONS: Although different degrees of torque were observed with different drilling dimensions and these resulted in different healing patterns, no differences in the histometrically evaluated parameters were observed.

Objective. To characterize the topographic and chemical properties of 2 bioceramic coated plateau root form implant surfaces and evaluate their histomorphometric differences at 6 and 12 weeks in vivo. Methods. Plasma sprayed hydroxyapatite (PSHA) and amorphous calcium phosphate (ACP) surfaces were characterized by scanning electron microscopy (SEM), interferometry (IFM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). Implants were placed in the radius epiphysis, and the right limb of dogs provided implants that remained for 6 weeks, and the left limb provided implants that remained 12 weeks in vivo. Thin sections were prepared for bone-to-implant contact (BIC) and bone-area-fraction occupancy (BAFO) measurements (evaluated by Friedman analysis P < 0.05). Results. Significantly, higher S(a) (P < 0.03) and S(q) (P < 0.02) were observed for ACP relative to PSHA. Chemical analysis revealed significantly higher HA, calcium phosphate, and calcium pyrophosphate for the PSHA surface. BIC and BAFO measurements showed no differences between surfaces. Lamellar bone formation in close contact with implant surfaces and within the healing chambers was observed for both groups. Conclusion. Given topographical and chemical differences between PSHA and ACP surfaces, bone morphology and histomorphometric evaluated parameters showed that both surfaces were osseoconductive in plateau root form implants.

Bisphosphonates (BPs) are the standard of care for patients with metastatic cancer and multiple myeloma to prevent skeletal complications (e.g., severe bone pain, pathologic fracture, etc.) and to treat osteoporosis. The cause and effect relationship between BPs and BP-related osteonecrosis of the jaws (BRONJ) is not well established. Current research suggests that bacterial biofilms may play a significant role in the pathogenesis of BRONJ. Recently, we have shown that BRONJ lesions are heavily colonized by oral bacteria and present many clinical challenges as they are difficult to culture and antibiotic resistance may result in misguided antibiotic therapy. Here we highlight the crosstalk among the oral bacteria and host immune response in BRONJ subjects. Using 16S rDNA molecular technique we characterize the total bacterial profile of BRONJ, BP and control subjects. Denaturing gradient gel electrophoresis cluster analysis revealed three clusters each representing the three groups, control, BP and BRONJ indicating that the microbiome present in tissue samples was distinct to each group. DGGE band pattern indicated that the BRONJ group had less bacterial diversity as compared to control indicating that high abundance of specific bacteria colonizing the BRONJ lesion. 16S sequencing and clonal analysis showed 6 phyla in all three groups. The phylum Firmicutes was predominant in BRONJ group (72%) followed by BP group (70%) as compared to control group (59%). The Chi-square test also showed significant differences in percent relative distribution of phyla, between control/BP groups (p<0.001), control/BRONJ (p<0.001) and BP/BRONJ (p<0.05). There was significantly increase in the gram positive bacteria in BRONJ group. PCR Array analysis indicated that the host genes responsible for antibacterial response such as MPO, CTSG, and NOD2 were significantly down regulated. Deficient innate immune responses to microorganisms together with poor healing and repair provide continuous opportunities for expanding!

As a strain rate-dependent material, bone has a different mechanical response to various loads. Our aim was to evaluate the effect of water and different loading/unloading rates on the nanomechanical properties of canine femur cortical bone. Six cross-sections were cut from the diaphysis of six dog femurs and were nanoindented in their cortical area. Both dry and wet conditions were taken into account for three quasistatic trapezoid profiles with a maximum force of 2000 muN (holding time = 30 s) at loading/unloading rates of 10, 100, and 1000 muN/s, respectively. For each specimen, 254 +/- 9 (mean +/- SD) indentations were performed under different loading conditions. Significant differences were found for the elastic modulus and hardness between wet and dry conditions (P < 0.001). No influence of the loading/unloading rates was observed between groups except for the elastic modulus measured at 1000 muN/s rate under dry conditions (P < 0.001) and for the hardness measured at a rate of 10 muN/s under wet conditions (P < 0.001). Therefore, for a quasistatic test with peak load of 2000 muN held for 30 s, it is recommended to nanoindent under wet conditions at a loading/unloading rate of 100-1000 muN/s, so the reduced creep effect allows for a more accurate computation of mechanical properties.