Faculty Bibliography

PURPOSE: To investigate the effect of core dental implant materials supporting single crowns on the probability of survival and failure modes. MATERIALS AND METHODS: Thirty-six standard external-hex titanium implants (4.0 mm in diameter) were selected to restore single crowns and divided into two groups according to core material: commercially pure grade 2 titanium (G2) and grade 5 titanium-aluminum-vanadium alloy (Ti-6Al-4V) (G5). Abutments were screwed to the implants, and standardized maxillary central incisor metal crowns were cemented and subjected to step-stress accelerated life testing in water. Use-level probability Weibull curves and reliability for missions of 100,000 cycles at 150 N and 200 N (with 90% two-sided confidence intervals [CIs]) were calculated. Polarized light and scanning electron microscopes were used to determine the failure modes. RESULTS: Use-level probability Weibull calculations showed beta values of 0.59 (CI, 0.31 to 1.11) and 1.22 (CI 0.81 to 1.84) for G2 and G5, respectively, and significantly higher characteristic strength and Weibull modulus for G5. The calculated reliability (90% CIs) for a mission of 100,000 cycles at 150 N showed that cumulative damage would lead to survival of 45% of implant-supported crowns of G2 and 98% of G5. At 200 N the probability of survival decreased to 0.03% for G2 and 21% for G5. Abutment screw fracture was the failure mode for all groups. CONCLUSION: Reliability, characteristic strength, and Weibull modulus were significantly higher for Ti-6Al-4V dental implants than for commercially pure (grade 2) titanium implants. Failure modes were similar for both groups.

Bilateral craniofacial microsomia causes obstructive sleep apnea (OSA). We hypothesize that unilateral craniofacial microsomia (UCFM) is an underappreciated cause of OSA. The records of all pediatric UCFM patients from 1990 to 2010 were reviewed; only complete records were included in the study. UCFM patients with OSA (apnea hypopnea index >1/hr) were compared to UCFM patients without OSA. Univariate and multivariate Fisher and chi tests were performed. Of the 62 UCFM patients, 7 (11.3%) had OSA. All OSA patients had Pruzansky IIB or III mandibles. OSA patients presented with snoring (71.4%), failure to thrive (FTT) (57.1%), and chronic respiratory infections (42.8%). Snoring (P < 0.001), Goldenhar syndrome (P = 0.001), and FTT (P = 0.004) were significantly associated with OSA, but race, obesity, clefts, respiratory anomalies, adenotonsillar hypertrophy, and laterality were not. The prevalence of OSA in UCFM patients is up to 10 times greater than in the general population. Snoring, Goldenhar syndrome, and FTT are significantly associated with the presence of OSA.

PURPOSE: To evaluate the effect of diamondlike carbon (DLC) coating on abutments and/or abutment screws on the reliability, characteristic strength, and Weibull modulus of implant-supported single crowns. MATERIALS AND METHODS: Seventy-two external hexagon implants (Emfills Implant 4 mm diameter, 10 mm length, Emfills) were divided into four groups (n = 18 each), according to the presence or not of a DLC coating in the abutment and/or abutment screw, as follows: abutment without coating, screw without coating (AwcSwc); abutment without coating with coated screw (AwcSC); abutment coated with noncoated screw (ACSwc), and coated abutment with coated screw (ACSC). Abutments and screws were evaluated with scanning electron microscopy. The specimens were subjected to step-stress accelerated life testing in water. Use-level probability Weibull curves and reliability for a mission of 100,000 cycles at 150 N (90% two-sided confidence intervals) were calculated. Polarized light and scanning electron microscopes were used for fractographic analysis. RESULTS: For a mission of 100,000 cycles at 150 N, reliability was 0.45 (0.20 to 0.67), 0.12 (0.00 to 0.47), 0.56 (0.17 to 0.82), and 0.44 (0.07 to 0.77) for AwcSwc, AwcSC, ACSwc, and ACSC, respectively. The probability Weibull calculation showed a Weibull modulus (m) of m = 5.50, m = 11.64, m = 16.96, and m = 15.08 and the characteristic strengths (eta, which indicates the load at which 63.2% of the specimens of each group fail) of eta = 202.67 N, eng = 206.64 N, eng = 192.54 N, and eng = 203.59 N for AwcSwc, AwcSC, ACSwc, and ACSC, respectively. Abutment screw fracture was the chief failure outcome in all groups. CONCLUSION: Characteristic strength values were not different among groups; neither was reliability. However, an increase in Weibull modulus (indicating low variability of the results) was observed with DLC coating of abutment or screw or both.

BACKGROUND: The purposes of this study were to report a 7-year experience of microvascular reconstruction of scalp defects, compare flap type and outcomes, and evaluate the implications of short and long term complications. METHODS: Following institutional review board approval, a single surgeon's patients requiring microvascular scalp reconstruction were retrospectively reviewed from 2005 to 2011. Flap choice, complications, and outcomes were statistically analyzed. RESULTS: Nineteen patients met inclusion criteria (10 male and 9 female) with a mean age of 60.2 +/- 21.4 years (range, 23-90 years). All free tissue transfers (n = 20) achieved 100% soft tissue coverage. Mean size calvarial defect was 106.6 +/- 67.2 cm (range, 35-285 cm), with 11 requiring cranioplasty. Free flaps included the following: 13 anteriolateral thigh, 5 ulnar, 1 latissimus dorsi, and 1 thoracodorsal artery perforator. Mean flap size was 154.1 +/- 87.3 cm (range, 42-336 cm). Early complications (<30 days following surgery) occurred in 21.1% of patients and late complications (>30 days following surgery) in 52.6% of patients. Patients with an early complication were 2 times more likely to develop a late complication (relative risk, 2.1) but did not reach statistical significance. Late complications were more likely to require surgical intervention, 84.2% versus 60% of early complications (P = 0.079). CONCLUSIONS: Microvascular free tissue transfer is the mainstay of complex scalp defects but carries a high likelihood of future reoperations. Early complications are less concerning than late complications, as the need for future surgical intervention is associated with late complications. There is lack of evidence to support a superior flap choice.

CONTEXT.: Approximately 30% of women report pain in the affected breast prior to breast cancer surgery. OBJECTIVES: The purpose of this secondary analysis of our prospective study was to determine how women who experienced both preoperative and persistent postsurgical breast pain (n=107) differed from women who did not report preoperative breast pain and did (n=158) or did not (n=122) experience persistent postsurgical breast pain. METHODS: Differences in demographic and clinical characteristics were evaluated. Linear mixed effects (LME) modeling was used to evaluate for group differences in symptom severity, function, sensation, and quality of life (QOL) over time. RESULTS: Between-group differences in demographic and clinical characteristics as well as trajectories of shoulder function and QOL were identified. Women with both preoperative and persistent postsurgical breast pain were younger; were more likely to report swelling, strange sensations, hardness, and numbness in the affected breast prior to surgery; and were more likely to have reconstruction at the time of surgery. Women with both preoperative and persistent postsurgical breast pain had more biopsies in the prior year, more lymph nodes removed, and reported more severe acute postsurgical pain than women without preoperative breast pain. LME modeling revealed significant group effects for the majority of outcomes evaluated. Over the six months of the study, women with both preoperative and persistent postsurgical pain had persistently poorer shoulder flexion and physical well-being than women without preoperative breast pain. CONCLUSION: Investigations of the etiology and molecular mechanisms of preoperative breast pain, as well as interventions for this high risk group, are needed.

Tracheostoma wounds are complex defects that commonly occur in patients with vessel-depleted necks after cervical lymphadenectomy, who have multiple medical comorbidities, and a history of radiation therapy. The authors report reconstruction of 5 tracheostoma wounds using a pedicled, supraclavicular artery island flap as a reconstructive alternative. There were no flap losses, fistulas or leaks, revisions, or other complications. The supraclavicular artery island flap is a versatile, reliable, and effective option for tracheostoma reconstruction.

Modern sarcoma treatment has created new challenges for plastic surgeons. This study was designed to review the recent experience and practice patterns following complex sarcoma resection at a large sarcoma center. All cases from October 2013 to October 2014 involving rare nonepithelial tumors, a multidisciplinary surgical team, radiation and/or chemotherapy treatments, and plastic surgical reconstruction were included in the analysis. In addition to evaluating clinical outcomes, cases were reviewed to identify factors associated with excellent or poor patient care. Review of these cases formed the basis of the greatest healing opportunity for soft tissue (GHOST) protocol. Our patient population included seven males (64%) and four females (36%). All except one patient was exposed to radiotherapy, chemotherapy, or some combination. Diverse procedures were used for reconstruction. Early complications occurred in two patients (18%), and late complications in four patients (36%). Sarcoma resection was found to be highly morbid in our series. Patients with poor preoperative nutritional status were more likely to experience complications postoperatively. The decision to stage a reconstruction was complex and influenced by several factors. Multimodal sarcoma treatments may involve highly morbid procedures and create complex wounds. The GHOST protocol is a useful reference for plastic surgeons.