Faculty Bibliography

PURPOSE/OBJECTIVE:This study evaluated the effect of different tightening protocols on the probability of survival of screw-retained implant-supported anterior crowns. MATERIALS AND METHODS/METHODS:Seventy-two implants with internal conical connections (4.0 × 10mm, Ti-6Al-4V, Colosso, Emfils) were divided into four groups (n = 18 each): 1) Manufacturer's recommendations torque (25 N.cm for abutment's screw and 30 N.cm for crown's screw) (MaT); 2) Retightening after 10 min (ReT); 3) Torque 16% below recommended to simulate an uncalibrated wrench (AgT), and; 4) Temporary crown simulation (TeT), where crowns were torqued to 13 N.cm to simulate manual tightening, subjected to 11,200 cycles to simulate temporary crown treatment time (190 N), and then retightened to manufacturer torque (TeT). All specimens were subjected to cyclic fatigue in distilled water with a load of 190 N until 250,000 cycles or failure. The probability of survival (reliability) to complete a mission of 50,000 cycles was calculated and plotted using the Weibull 2-Parameter analysis. Weibull modulus and number of cycles at which 62.3% of the specimens would fail were also calculated and plotted. The failure mode was characterized in stereo and scanning electron microscopes (SEM). RESULTS:The probability of survival was 69.3% for MaT, 70% for ReT, 54.8% for AgT, and 40.3% for TeT, all with no statistically significant difference. Weibull modulus was approximately 1.0 for all groups. The characteristic number of cycles for failure was 105,000 cycles for MaT, 123,000 for ReT, 82,000 cycles for AgT, and 54,900 cycles for TeT, with no significant difference between groups. The chief failure mode for MaT, ReT, AgT groups was crown screw fracture, whereas abutment screw fracture was the chief failure mode for the TeT group. CONCLUSION/CONCLUSIONS:Tightening protocol did not influence the probability of survival of the screw-retained anterior crowns supported by internal conical implants (Ti-6Al-4V, Colosso, Emfils).

PURPOSE/OBJECTIVE:Pre-surgical point-of-care (POC) pregnancy testing in women of child-bearing age has become routine practice in hospitals across the United States. Its application in the ambulatory care setting is less ubiquitous. The authors herein present its application in their outpatient oral and maxillofacial surgery clinic, as implemented prior to procedures under intravenous sedation. METHODS:This study was implemented as a retrospective, single-center review of clinical records. The authors examined data from Bellevue Hospital Center's oral and maxillofacial surgery clinic for women of child-bearing age undergoing outpatient procedures performed under intravenous sedation during a 22 month time period. The review focused on POC urine human gonadotropin (hCG) results. A basic statistical analysis was performed on the data. Additionally, an examination of the associated costs of this testing was performed. RESULTS:The study included women between 12 and 50 years of age, of which there were 176. Five of the subjects (2.8%) were found to have an elevated hCG suggestive of pregnancy. The average age of those found to be pregnant was 22. All patients were originally scheduled for extraction of third molars. The cost of a single POC hCG test at the authors' institution was $2.00. The cost to identify a single pregnancy within the study period was found to be $70.40. CONCLUSION/CONCLUSIONS:In the authors' experience, POC hCG testing for women of childbearing age is easily integrated into a standardized pre-sedation workflow. Although the medications utilized for outpatient sedation procedures are generally considered safe for both mothers and developing fetuses, implementation of POC hCG testing allows for providers and patients to make more fully informed decisions regarding how to proceed with elective cases in the case of a previously undiagnosed pregnancy. Determination of pregnancy status prior to a procedure may prompt referral for appropriate prenatal care, while limiting surgeons' exposure to medicolegal liability. This study contributes to a small body of extant reports from ambulatory surgery centers and outpatient clinics offering IV sedation, offering providers a context in which to consider their own implementation of routine hCG testing.

A combined surgical and orthodontic approach to midface and mandibular distraction optimizes stability and outcomes. Orthodontic considerations include proper planning of the distraction vector, appropriate device use, and thorough follow-up through the consolidation and postoperative period. The dental occlusion must be managed throughout treatment in order to achieve ideal results.

BACKGROUND:β-Tricalcium phosphate (β-TCP) is one of the most common synthetic bone grafting materials utilized in craniofacial reconstruction; however, it is limited by a slow degradation rate. The aim of this study was to leverage 3-dimensional (3D) printing in an effort to accelerate the degradation kinetics of β-TCP. METHODS:Twenty-two 1-month-old New Zealand white rabbits underwent creation of calvarial and alveolar defects, repaired with 3D-printed β-TCP scaffolds coated with 1000 μM of osteogenic agent dipyridamole. Rabbits were euthanized after 2, 6, and 18 months after surgical intervention. Bone regeneration, scaffold degradation, and bone mechanical properties were quantified. RESULTS:Histological analysis confirmed the generation of vascularized and organized bone. Microcomputed tomography analysis from 2 to 18 months demonstrated decreased scaffold volume within calvarial (23.6% ± 2.5%, 5.1% ± 2.2%; P < 0.001) and alveolar (21.5% ± 2.2%, 0.2% ± 1.9%; P < 0.001) defects, with degradation rates of 54.6%/year and 90.5%/year, respectively. Scaffold-inducted bone generation within the defect was volumetrically similar to native bone in the calvarium (55.7% ± 6.9% vs 46.7% ± 6.8%; P = 0.064) and alveolus (31.4% ± 7.1% vs 33.8% ± 3.7%; P = 0.337). Mechanical properties between regenerated and native bone were similar. CONCLUSIONS:Our study demonstrates an improved degradation profile and replacement of absorbed β-TCP with vascularized, organized bone through 3D printing and addition of an osteogenic agent. This novel additive manufacturing and tissue engineering protocol has implications to the future of craniofacial skeletal reconstruction as a safe and efficacious bone tissue engineering method.

PURPOSE/OBJECTIVE:The aim of this study was to qualitatively and quantitatively assess the effect of osteotomy preparation by conventional, subtractive, or osseodensification instrumentation on osteotomies, treated with or without endosteal implants, and healing capacity. MATERIALS AND METHODS/METHODS:Seven sheep were used, and 56 osteotomies were made in the left and right ilium of the sheep (n = 8/sheep [4 per side/time point (3 and 6 weeks)]). Two different instrumentation techniques were used: (1) conventional/regular drilling in a three-step series of a 2-mm pilot and 3.2-mm and 3.8-mm twist drills and (2) osseodensification drilling with a Densah Bur 2.0-mm pilot and 2.8-mm and 3.8-mm multi-fluted tapered burs. Drilling was performed at 1,100 rpm with saline irrigation. RESULTS:Qualitative histomorphometric evaluation of the osteotomies after 3 and 6 weeks did not indicate any healing impairment due to the instrumentation. In all samples, histologic examination suggested bone remodeling and growth (empty and treated with an implant), irrespective of preparation technique. Osteotomies prepared using the osseodensification instrumentation showed the existence of bone chips autografted into the trabecular spaces along the length of the osteotomy wall. CONCLUSION/CONCLUSIONS:The osseodensification group yielded higher osseointegration rates, as distinguished through qualitative assessment, bone-to-implant contact, and bone-area-fraction occupancy, indicating an increased osteogenic potential in osteotomies prepared using the osseodensification technique.

OBJECTIVE:To characterize the biomechanical performance of fiber-reinforced composite 5-unit implant-supported fixed dental prostheses (FDPs) receiving individually milled crowns by insilico and fatigue analyses. METHODS:Eighteen implant-supported five-unit fiber-reinforced composite frameworks with an individually prepared abutment design were fabricated, and ninety resin-matrix ceramic crowns were milled to fit each abutment. FDPs were subjected to step-stress accelerated-life testing with load delivered at the center of the pontic and at 2nd molar and 1st premolar until failure. The reliability of the prostheses combining all loaded data and of each loaded tooth was estimated for a mission of 50,000 cycles at 300, 600 and 900 N. Weibull parameters were calculated and plotted. Fractographic and finite element analysis were performed. RESULTS:Fatigue analysis demonstrated high probability of survival at 300 N, with no significant differences when the set load was increased to 600 and 900 N. 1st and 2nd molar dataset showed high reliability at 300 N, which remained high for the higher load missions; whereas 1st premolar dataset showed a significant decrease when the reliability at 300 N was compared to higher load missions. The characteristic-strength of the combined dataset was 1252 N, with 1st molar dataset presenting higher values relative to 2nd molar and 1st premolar, both significantly different. Failure modes comprised chiefly cohesive fracture within the crown material originated from cracks at the occlusal area, matching the maximum principal strain location. SIGNIFICANCE/CONCLUSIONS:Five-unit implant-supported FDP with crowns individually cemented in a fiber-reinforced composite framework presented a high survival probability. Crown fracture comprised the main failure mode.

Background/UNASSIGNED:The majority of two-stage prepectoral breast reconstruction has been described utilizing acellular dermal matrix (ADM). Although reports of prepectoral breast reconstruction without ADM exist, there is a paucity of comparative studies. Methods/UNASSIGNED:A single-institution retrospective review was performed of consecutive patients undergoing immediate prepectoral two-stage breast reconstruction with tissue expanders from 2017 to 2019. Short-term reconstructive and aesthetic complications were compared between cases that utilized ADM for support and those that did not. Results/UNASSIGNED:0.362). Conclusions/UNASSIGNED:Immediate two-stage prepectoral breast reconstruction with tissue expanders has comparable rates of short-term complications with or without ADM support. Safety of prepectoral expander placement without ADM may warrant more selective ADM use in these cases.

BACKGROUND:Corticosteroid injections have proven benefit in the treatment of symptomatic trigger finger; however, the immune system and tissue repair modulating properties of corticosteroids justify further consideration in surgical candidates. The aim of this study was to assess the relationship between corticosteroid injections and postoperative infection in trigger finger release. METHODS:A single-center retrospective review was conducted of patients seen from 2010 to 2019 to identify those who underwent trigger finger release with subsequent antibiotic prescription for chart-documented wound infection. A demographic matched cohort of 100 patients was identified for comparison. Preoperative corticosteroid injection history including timing, frequency, and dose was collected for all patients. Patient demographics, comorbidities, and presence of postoperative infection were collected from patient medical records. Superficial infection was defined as those requiring antibiotics for resolution without return to the operating room; deep infection was defined as infections that required irrigation and debridement. RESULTS:= .04). CONCLUSIONS:While corticosteroid injection in the preoperative period is associated with a higher rate of postoperative infection, the time before surgery and the corticosteroid dose do not appear to have an effect.