Faculty Bibliography

BACKGROUND: Patients undergoing autologous breast reconstruction have higher long-term satisfaction rates compared with those undergoing prosthetic reconstruction. Regardless, most patients still undergo prosthetic reconstruction. The authors compared outcomes of microsurgical reconstruction to those of prosthetic reconstruction in thin patients and evaluated the effect of reconstructive type on quality of life. METHODS: After institutional review board approval was obtained, the authors reviewed all patients undergoing breast reconstruction at a single institution from November of 2007 to May of 2012. Thin patients (body mass index <22 kg/m) were included for analysis and divided into two cohorts: microsurgical reconstruction and tissue expander/implant reconstruction. Once identified, patients were mailed a BREAST-Q survey for response; a retrospective chart review was also conducted. RESULTS: A total of 273 patients met inclusion criteria: 81.7 percent (n = 223) underwent tissue expander/implant reconstruction and 18.3 percent (n = 50) underwent microsurgical reconstruction. Of the patients undergoing microsurgical reconstruction, 50 percent (n = 25) responded to the BREAST-Q survey, whereas 48.4 percent of patients (n = 108) with implant reconstruction were responders. Microsurgical patients required more secondary revision [48 percent (n = 12) versus 25.9 percent (n = 28)] and autologous fat grafting [32 percent (n = 8) versus 16.9 percent (n = 19)] and a greater volume of fat per injection (147.85 ml versus 63.9 ml; p < 0.001). Furthermore, BREAST-Q responses showed that these patients were more satisfied with their breasts (71.1 percent versus 64.9 percent; p = 0.004), but had similar overall satisfaction with reconstruction (73.0 percent versus 74.8 percent; p = 0.54). CONCLUSIONS: Microsurgical breast reconstruction is efficacious in patients with a body mass index less than 22 kg/m and, when compared with prosthetic reconstruction, results in higher satisfaction with breasts. However, it requires more secondary revision surgery and the use of autologous fat grafting as an adjunct. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Alopecia-neurological defects-endocrinopathy (ANE) syndrome is a rare inherited hair disorder, which was shown to result from decreased expression of the RNA-binding motif protein 28 (RBM28). In this study, we attempted to delineate the role of RBM28 in hair biology. First, we sought to obtain evidence for the direct involvement of RBM28 in hair growth. When RBM28 was downregulated in human hair follicle (HF) organ cultures, we observed catagen induction and HF growth arrest, indicating that RBM28 is necessary for normal hair growth. We also aimed at identifying molecular targets of RBM28. Given that an RBM28 homologue was recently found to regulate miRNA biogenesis in C. elegans and given the known pivotal importance of miRNAs for proper hair follicle development, we studied global miRNA expression profile in cells knocked down for RBM28. This analysis revealed that RBM28 controls the expression of miR-203. miR-203 was found to regulate in turn TP63, encoding the transcription factor p63, which is critical for hair morphogenesis. In conclusion, RBM28 contributes to HF growth regulation through modulation of miR-203 and p63 activity.

OBJECTIVES: To evaluate the influence of implant-abutment interface (IAI) placement depth on bone remodeling around implants with two different types of tapered internal IAI: screwed-in (SI) and tapped-in (TI) connections in dogs. MATERIALS AND METHODS: Eight weeks post mandibular tooth extraction in six beagle dogs, two SI implants (OsseoSpeed , Astra Tech, DENTSPLY) and two TI implants (Integra-CP , Bicon LLC) were placed in one side of the mandible. The four experimental groups were as follows: (i) SI-placed equicrestally (SIC); (ii) TI-placed equicrestally (TIC); (iii) SI-placed 1.5 mm subcrestally (SIS); and (iv) TI-placed 1.5 mm subcrestally (TIS). Healing abutments were connected 12 weeks after implant placement. Sixteen weeks later, the dogs were sacrificed and histomorphometric analysis was performed. Histometrical outcomes were evaluated using a nonparametric Brunner-Langer model. RESULTS: Mean distance from the IAI to first bone-implant contact (IAI-fBIC) was 0.88 mm (median: 0.77; SD: 0.54) for SIC group, 1.23 mm (median: 1.22; SD: 0.66) for TIC group, 0.41 mm (median: 0.31; SD: 0.36) for SIS group, and 0.41 mm (median: 0.26; SD: 0.45) for TIS group. Subcrestal groups showed lower IAI-fBIC compared with equicrestal groups (P < 0.001). Connective tissue presented similar measurements regardless of the IAI placement depth and IAI type (P > 0.05), but the epithelium length and peri-implant soft tissue length in subcrestal groups were significant larger than that in the equicrestal groups (P < 0.001 and P = 0.004, respectively). CONCLUSION: Subcrestal implant placement with tapered internal IAI is beneficial for bone contact with the implant neck, and concurrently, it may not increase the soft tissue inflammation around IAI.

BACKGROUND: This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols. STUDY DESIGN: Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques were: until 3.75 mm (regular-group); and until 4.0 mm diameter (overdrilling-group) for both implant designs. At 2 and 4 weeks, samples were retrieved and processed for histomorphometric analysis. For torque and BIC (bone-to-implant contact) and BAFO (bone area fraction occupied), a general-linear model was employed including instrumentation technique and time in vivo as independent. RESULTS: The insertion torque recorded for each implant design and drilling group significantly decreased as a function of increasing drilling diameter for both implant designs (p<0.001). No significant differences were detected between implant designs for each drilling technique (p>0.18). A significant increase in BIC was observed from 2 to 4 weeks for both implants placed with the overdrilling technique (p<0.03) only, but not for those placed in the 3.75 mm drilling sites (p>0.32). CONCLUSIONS: Despite the differences between implant designs and drilling technique an intramembranous-like healing mode with newly formed woven bone prevailed.

OBJECTIVES: To define the effect of APP treatments on the mechanical properties of enamel and on its ability to promote sealant bonding to unetched enamel. METHODS: Human molar teeth were sectioned exposing flat enamel regions at the buccal and lingual surfaces. The specimens were divided into two substrate groups (etched and unetched) and distributed over three surface treatments (i) 5 slm Argon APP treatment, NaOH surface treatment, and (iii) compressed air application (control). The Enamel surfaces were characterized by SEM, IFM, and Goniometer instruments. For the mechanical tests nanoindentation and microshear bond strength were employed. Initial data evaluation comprised normality verification (SPS S software) and variance checking and the appropriated statistical analysis model employed. For all statistical inferences, significance was set at 0.05. RESULTS: SE was significantly higher for the etched and unetched group treated with Plasma relative to the NaOH and control groups. Nanoindentation testing determined that Rank hardness was significantly higher in the control and Plasma group relative to NaOH for the etched group. Rank Elastic Modulus was significantly higher on Control groups relative to NaOH and Plasma groups for the etched substrate. No difference was detected between treatments for the unetched group. For the microSBS test, we observed that APP treatment on etched and unetched enamel increased bonds significantly (p < 0.001). CONCLUSIONS: This study demonstrated that APP increased SE, surface wettability and bond strength between enamel and sealants potentially serving as a substitute for conventional acid etching procedures or as an adjuvant for self-etch sealants. (c) 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014.

Our aim was to find out whether simplified drilling protocols would provide biological responses comparable to those of conventional drilling protocols at the low rotational speed of 400rpm. Seventy-eight root form endosseous implants with diameters of 3.75, 4.2, and 5mm were placed into canine tibias and allowed to heal for 3 and 5 weeks. After the dogs had been killed, the samples of implanted bone were retrieved and processed for non-decalcified histological sectioning. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) analyses were made on the histological sections. Implants treated by the simplified protocol resulted in BIC and BAFO values comparable to those obtained with the conventional drilling protocol, and there were no significant differences in the technique or diameter of the drilling. The results suggest that the simplified procedure gives biological outcomes comparable to those of the conventional procedure.