Faculty Bibliography

The human vocal fold is a complex structure made up of distinct layers that vary in cellular and extracellular matrix composition. Elucidating the mechanical properties of vocal fold tissues is critical for the study of both acoustics and biomechanics of voice production, and essential in the context of vocal fold injury and repair. Both quasistatic and dynamic behavior in the 10-300Hz range was explored in this preliminary investigation. The resultant properties of the lamina propria were compared to that of the nearby thyroarytenoid muscle. Er, quantified via quasistatic testing of the lamina propria, was 609+/-138MPa and 758+/-142MPa in the muscle (p=0.001). E' of the lamina propria as determined by dynamic testing was 790+/-526MPa compared to 1061+/-928MPa in the muscle. Differences in E' did not achieve statistical significance via linear mixed effect modeling between the tissue types (p=0.95). In addition, frequency dependence was not significant (p=0.18).

BACKGROUND: Prior studies report a high incidence of airway complications in patients with Robin sequence following palatoplasty. The authors' institution uses polysomnography to assess risk of airway compromise before palatoplasty in Robin sequence. This study compares airway complications in Robin sequence to cleft palate only using this screening airway protocol and identifies risk factors for airway complications after palatoplasty. METHODS: A 12-year retrospective review of patients with Robin sequence undergoing palatoplasty was performed. Robin sequence patients were divided into nonoperative management and mandibular distraction osteogenesis subgroups. Preoperative variables including comorbidities were recorded. The primary outcome was postoperative airway complication, defined as reintubation, emergency room visit, or hospital admission within 3 months of palatoplasty. RESULTS: One hundred thirteen patients met inclusion criteria: polysomnography, 34.5 percent; Robin sequence, 65.5 percent; and Robin sequence treated with mandibular distraction osteogenesis, 30.1 percent. Screening polysomnography was used to indicate patients for palatoplasty or other airway interventions. The total airway complication rate was 7.1 percent; this was similar in Robin sequence (5.8 percent) and cleft palate only (7.7 percent). In isolated Robin sequence, the reintubation rate was 0 percent. Lower airway anomalies were associated with airway complications (p = 0.03). Significant variables for reintubation were cardiac (p = 0.046), gastrointestinal (p = 0.04), and lower airway anomalies (p = 0.025) and syndromic diagnosis (p = 0.05). CONCLUSION: Screening polysomnography can control airway complications following palatoplasty in Robin sequence patients to a rate that is comparable to that of patients with cleft palate only.

Osseointegration of metallic devices has been one of the most successful treatments in rehabilitative dentistry and medicine over the past five decades. While highly successful, the quest for designing surgical instrumentation and associated implantable devices that hastens osseointegration has been perpetual and has often been approached as single variable preclinical investigations. The present manuscript presents how the interplay between surgical instrumentation and device macrogeometry not only plays a key role on both early and delayed stages of osseointegration, but may also be key in how efficient smaller length scale designing (at the micrometer and nanometer scale levels) may be in hastening early stages of osseointegration.

This study investigated whether the use of a dual-layer polytetrafluoroethylene (PTFE)/porcine-derived bioresorbable pericardium membrane enhances the osseointegration around implants compared to a single-layer porcine-derived bioresorbable pericardium membrane and a no-membrane control group. Endosseous implants were placed in the fresh extraction sockets of beagles. At 6 weeks, bone loss and apical soft tissue migration occurred in the control group, whereas bone successfully formed to the neck of the implant for the single-layer porcine-derived bioresorbable pericardium membrane group. The dual-layer PTFE/ porcine-derived bioresorbable pericardium membrane showed bone growth coronal to the neck of the implant. Bone-to-implant contact and buccal bone loss were respectively higher and lower relative to the single-layer but not statistically different.

OBJECTIVE: To evaluate costs associated with surgical treatment for neonates with Pierre Robin sequence (PRS). STUDY DESIGN: Retrospective cohort study. SETTING: Cincinnati Children's Hospital Medical Center. SUBJECTS AND METHODS: With Institutional Review Board approval, we retrospectively studied neonates with PRS treated from 2001 to 2009 with either tracheostomy (Trach), mandibular distraction (MD), or Trach with subsequent MD (Trach+MD). Actual charges over a 3-year period associated with operative costs, hospital stay, imaging and sleep studies, clinic visits, and related emergency room visits were collected. Home tracheostomy care charges were estimated individually for each patient. Charges were compared using regression and appropriate statistical analyses. RESULTS: Forty-seven neonates were included in the study (MD, n = 26; Trach, n = 12; Trach+MD, n = 9). Trach group patients had 2.6-fold higher charges than the MD group despite no difference in length of hospital stay. This difference increased to 7.3-fold when including home trach care-related costs. Trach+MD group patients had longer hospital lengths of stay and higher operation room (OR) fees, but no increased total charges compared with the Trach only group. CONCLUSIONS: For patients with severe PRS, mandibular distraction provides significant cost savings over tracheostomy ($300,000 per patient over 3 years). Increased costs with tracheostomy come from greater hospital-related charges, more frequent airway procedures, a higher incidence of gastrostomy tube feeds, and home trach care costs. A careful examination of long-term outcomes will be critical as mandibular distraction continues to gain acceptance for treatment of PRS.

OBJECTIVES: To observe and to compare histologically and histomorphometrically, the combined effect of drilling sequence and implant diameter in vivo. MATERIAL AND METHODS: A total of 72 alumina-blasted and acid-etched Ti-6Al-4V implants with three different diameters (3.75, 4.2, and 5 mm, n = 24 for each group) were placed in the right and left tibiae of 12 beagle dogs. Within the same diameter group, half of the implants were inserted after a simplified drilling procedure (pilot drill + final diameter drill) on one tibia and the other half were placed using the conventional drilling procedure on the other tibia. After 1 week, half of the animals (n = 6) were sacrificed, and the other half was sacrificed after 5 weeks (n = 6). The retrieved bone-implant samples were subjected to non-decalcified histologic sectioning, and the bone-to-implant contact (BIC) and the bone area fraction occupancy (BAFO) were analyzed. Primary statistical analysis used a mixed model analysis of variance with significance level set at P < 0.05. RESULTS: Histologic observation showed that at 1 week, immature woven bone formed in vicinity of the implant, whereas at 5 weeks, the woven bone was replaced by lamellar bone, which formed in proximity with the implant. Histomorphometrically, the simplified technique was associated with significantly greater BIC and BAFO after 1 week. Differences between techniques were not longer apparent after 5 weeks, but BAFO was inversely and significantly associated with implant diameter at that time. CONCLUSIONS: The simplified technique did not impair either early or late bone formation for any tested implant diameter; however, wider diameters were associated with less bone formation at longer healing times for both techniques.

Mandibular distraction has revolutionized the treatment of Robin sequence associated with severe airway obstruction. The distraction technique remains the only intervention that directly corrects mandibular hypoplasia and the retropositioned tongue, providing efficient relief of airway stenosis. Multiple studies have demonstrated the efficacy of distraction in avoiding tracheostomy and decreasing the severity airway obstruction in this patient population. The benefit to avoiding tracheostomy and relieving airway obstruction is superior to that of tongue-lip adhesion. It is, therefore, not surprising that mandibular distraction has become the first-line intervention at many centers for the surgical treatment of Robin sequence. The complication profile associated with mandibular distraction appears low; the most common complication is infection, which can be treated by antibiotics alone. The severity of airway obstruction can be quantified by polysomnogram: This tool has become one of the most widely used objective metrics in the Robin sequence population. Therefore indications for surgery, timing of palatoplasty and long-term assessment of airway function should be performed in conjunction with sleep study analysis. The effects of mandibular lengthening on feeding difficulty in Robin sequence patient remains a topic of controversy. Studies have demonstrated conflicting results: This can be an area of future study. Agreed-upon indications for surgery and definitive protocols of care have yet to be formulized; future research should focus on achieving these goals. Such studies would require agreed-upon terminology for Robin sequence, an increase in comparative and prospective analysis, and the use of quantifiable metrics of clinical results.