Accuracy and clinical outcomes of mandibular reconstruction with a virtually planned deep circumflex iliac artery flap with stock temporomandibular joint prosthesis.

The repair of hemimandibulectomy defects involving the temporomandibular joint (TMJ) is challenging. This study compared the functional outcomes and reconstruction accuracy using a deep circumflex iliac artery (DCIA) flap with and without a virtually planned stock TMJ prosthesis (TMJP) after hemimandibulectomy. Ten patients were assessed: five with a TMJP (TMJP group) and five without (control group). A three-dimensional comparison revealed a mean deviation of 0.11 ± 0.04 mm between the planned and actual DCIA flap with TMJP. The planned and actual TMJP positions differed by 0.56 ± 0.57 mm in height, 0.33 ± 0.24 mm ventrally/dorsally, and 1.18 ± 0.42 mm medially/laterally. Mouth opening, laterotrusion, and midline deviation were significantly greater in the control group than in the TMJP group (P = 0.024, P = 0.008, P = 0.024). The deviation in ventral to dorsal translation for the DCIA flap was slightly higher than reported values in the literature, while height deviation was comparable. Lower deviations in the literature were due to the DCIA flap being used where both TMJs were intact. The in-house virtually planned DCIA flap with stock TMJP yielded results comparable to more expensive patient-specific prostheses.

Autologous point-of-care stromal vascular fraction transplantation in dogs with advanced osteoarthritis of the knee and hip joints.

OBJECTIVE: The aim of the study was to assess lameness in dogs with advanced osteoarthritis of the hip and knee joints after a single autologous point-of-care transplantation of the Stromal Vascular Fraction (SVF) into the affected joint. MATERIALS AND METHODS: During a minilaparotomy, 10 g of falciform fat was removed from each patient for each joint to be treated. A modern and time-saving procedure (ARC TM System, InGeneron GmbH, Houston, USA) was used for the in-house preparation of the SVF, so that the isolated cells could be applied to the respective joint within 2 h after fat removal. In total, five knee joints of five patients and seven hip joints of four patients were treated. RESULTS: Improvement in lameness according to owner questionnaires was seen in 3 of 5 patients with knee joint arthritis and 2 of 4 patients with hip joint arthritis. Based on gait analysis, only one dog with gonarthrosis and one dog with coxarthrosis showed improvement up to a maximum of 3 months after surgery. CONCLUSION: This is the first case series on the treatment of osteoarthrosis of the knee or hip joint using point-of-care transplantation of the SVF. In individual cases, this method may represent a therapeutic approach for the treatment in dogs with advanced cox- or gonarthrosis, although only a short-term effect can be expected, which calls into question the effort and costs involved.

Evaluation of anterolateral thigh flap dimensions with virtual flap models.

Free flaps are commonly used for head and neck reconstruction. However, flap dimensions are still evaluated by visual and tactile assessment. The aim of this study was to enable preoperative planning of flap dimensions for soft tissue reconstruction based on clinical parameters. Computed tomography records from 230 patients dated from 2009 to 2019 were analysed retrospectively. A virtual, three-dimensional anterolateral thigh flap model was standardized, aligned to segmented leg models in two positions, and flap thicknesses and volumes were determined. Associations of flap thickness and volume with clinical parameters were evaluated, and an approximative calculation method was derived. The laterally positioned anterolateral thigh flap showed an average (interquartile range) thickness of 15.6 mm (8.7 mm) and volume of 1.5 cm3 (0.9 cm3) per cm2. The medially positioned anterolateral thigh flap showed an average (interquartile range) thickness of 16.3 mm (8.7 mm) and volume of 1.6 cm3 (0.9 cm3) per cm2. For both flap positions, leg circumference was the strongest predictor of flap thickness (ß = 0.545, P < 0.001 and ß = 0.529, P < 0.001) and flap volume (ß = 0.523, P < 0.001 and ß = 0.480, P < 0.001). Flap dimensions can be calculated based on leg circumference, and this preoperative planning of flap dimensions can help the surgeon to select the appropriate flap.

Unusual histopathological findings in appendectomy specimens with clinical diagnosis of acute appendicitis: A retrospective cohort analysis.

INTRODUCTION: While appendicitis is considered one of most common acute surgical conditions, several studies have reported abnormal histopathological findings in appendectomy specimens; however, sending all appendices to histopathology is not yet routinely done.Here we report many unusual findings. Those unusual findings played a role not only in confirming acute appendicitis as a cause of the presentation in some cases but also discovering etiologies that mimic it with great impact on its management. METHODS: Between January 2011 and December 2017, a total of 1510 patients were operated with appendectomy for a primary diagnosis of acute appendicitis. Among them, a total of 72 patients had incidental histopathologic findings in association with acute appendicitis or other pathologies instead of acute appendicitis. A retrospective analysis for those 72 patients was performed with all data being retrieved from the electronic health record system. RESULTS: Patients ages ranged between 4 and 71 years with a mean age equal to 23.1 years (SD = 14.2). Majority of patients were women (n = 52; 72.2%). Sixty of the seventy-two cases were seen in patients with negative appendectomies (n = 333) with an overall rate of 18% among this group of patients. The remaining 12 patients had additional findings in histopathology specimens beside acute appendicitis (n = 1131) with an overall rate of 1%. The most commonly reported pathologies were serositis, ovarian cysts, and Enterobius vermicularis in descending frequency. CONCLUSION: Identification of unusual histopathological findings during microscopic examination of resected appendices is more common in female patients and in patients with negative appendectomy. histopathologic assessment of specimens will allow detection of congenital, infectious or malignant pathologies that mimic acute appendicitis clinically even in the absence appendicitis microscopically.

Simulation of three surgical techniques combined with two different bone-borne forces for surgically assisted rapid palatal expansion of the maxillofacial complex: a finite element analysis.

Surgically assisted rapid palatal expansion (SARPE) is a common treatment to correct transverse maxillary deficiencies. Finite element analysis was simulated for six designs of SARPE based on a computed tomography scan of a human skull: median osteotomy with palatal (type A) or alveolar ridge (type B) bone-borne force, additional lateral osteotomy with palatal (type C) or alveolar ridge (type D) bone-borne force, and additional pterygomaxillary separation with palatal (type E) or alveolar ridge (type F) bone-borne force. The transverse expansion was about 1.0mm. The distribution of von Mises stress and the displacement were evaluated. The largest stress distribution was after types A and B, followed by types C and D, and finally types E and F. Displacement increased simultaneously. Palatal bone-borne forces (types A, C, and E) led to higher stress distributions in the midface and maxilla, but to a more parallel expansion compared with alveolar ridge-borne forces (types B, D, and F). The largest bony displacements at the midpalatal suture were anterior in all models. Increased weakening of the bony pillar of the facial skeleton and the use of palatal bone-borne forces leads to a decrease in stress distribution in the midface and to a more parallel transverse expansion of the maxilla.

Long-term outcome after surgical treatment of cranial cruciate ligament rupture in small breed dogs. Comparison of tibial plateau leveling osteotomy and extra-articular stifle stabilization.

OBJECTIVE: Cranial cruciate ligament rupture is the most frequently occurring disease of the canine stifle. After introduction of corrective osteotomies of the proximal tibia as surgical treatment option in medium, large and giant breeds, the tibial plateau leveling osteotomy (TPLO) evolved into one of the favorite procedures. In the past small breed dogs have usually been treated by extra-articular stabilization techniques. TPLO has recently become an accepted treatment method in these breeds as well as, and is nowadays used with increasing frequency. The purpose of this study was to evaluate long-term outcomes of TPLO compared to an extra-articular stabilization technique in small breed dogs. MATERIAL AND METHODS: A total of 40 stifles of 30 small breed dogs weighing ≤ 15 kg were treated for cranial cruciate ligament rupture with either TPLO (n = 23) or a lateral capsular-fascial imbrication technique (CFI; n = 17). Dogs were clinically examined before and at least 6 months after surgery by treadmill analysis and radiography. Moreover a questionnaire was provided to the owners to assess postoperative function and overall satisfaction. RESULTS: Twenty-one of 23 operated limbs (91.3%) treated with TPLO and five of 17 (29.4%) treated with the CFI showed absolute values comparable to healthy dogs when evaluated by peak vertical force, vertical impulse and its symmetry index during objective gait analysis. Both groups showed mild, but continuous progression of osteoarthritis. TPLO led to a significantly faster recovery and a higher degree of owner satisfaction. CONCLUSION: Based on clinical examination and objective gait analysis TPLO yielded excellent long-term results and a high degree of owner satisfaction in small breed dogs ≤ 15 kg treated for cranial cruciate ligament rupture. CLINICAL RELEVANCE: TPLO seems to be superior to CFI treatment of small breed dogs in this study, although CFI should be considered as treatment option under certain circumstances.

Stability of edentulous, atrophic mandibles after insertion of different dental implants. A biomechanical study.

OBJECTIVES: Fractures of the atrophic edentulous mandible are a rare complication that can become severe after the insertion of dental implants. This in vitro study investigated the effects of different implant settings varying in number, diameter, and length. and the influence of a fixed bar. MATERIALS AND METHODS: In biomechanical experiments on artificial mandibles, an unmodified reference group, four implant settings with two different implants, and the effect of adding a fixed bar to these settings were tested. All specimens were loaded with incisal biting forces until failure due to fracture. RESULTS: Implants weakened all specimens significantly compared with those in the reference group. Without a fixed bar, four short and thick implants showed the best results, with high significance. With a fixed bar, four long and thin implants withstood the highest loads. The addition of fixed bars reduced the differences between the implant settings. Fixed bars did not show increased stability for all groups; however, these groups showed a higher mean strength. CONCLUSIONS: Four implants with a short and thick design should be the first choice when implants are placed without a fixed bar in an atrophic mandible. With a fixed bar, four long and thin implants should be used.

Which kind of frontal mandibulotomy is the smartest? A biomechanical study.

PURPOSE: Retrospective clinical evaluation and biomechanical tests were performed to compare the primary stability and the rate of pseudarthrosis formation after irradiation for two types of mandibular split osteotomies: the stairstep osteotomy (SSO) and the straight-line osteotomy (SLO). METHODS: The postoperative occurrence of pseudarthrosis was retrospectively analysed in 46 non-consecutive clinical cases of SSO and SLO between 2003 and 2013. Biomechanical tests were performed on 12 standardised synthetic mandibles (Synbone) to compare the SSO and SLO approaches. Two 2.0 mm monocortical miniplates (Medartis) were used for osteosynthesis. The artificial mandible specimens were loaded to 300 N on the Mandibulator test bench while interfragmentary motion was measured using the PONTOS optical measurement device. RESULTS: The retrospective clinical analysis showed a rate of pseudarthrosis of 19% in the SLO group versus only 5% in the SSO group (p = 0.17). In the biomechanical investigation, the average interfragmentary movement was 14.3 ± 7.70 for the SLO group and 4.57 ± 2.33 for the SSO group under a maximum load of 300 N, resulting in a statistically significant difference between the two approaches (p = 0.014). CONCLUSION: To minimise the rate of postoperative pseudarthrosis formation, SSO is superior to SLO for mandibular split procedures, because SSO provides greater resistance to vertical loads and allows less interfragmentary movement. LEVEL OF EVIDENCE: 2C (Outcomes research).

Experimental biomechanical study of the primary stability of different osteosynthesis systems for mandibular reconstruction with an iliac crest graft.

We did biomechanical loading tests to compare the quantity and quality of interfragmentary movement in fractured human cadaver mandibles that had been reconstructed with iliac crest using 3 different osteosynthesis systems. Eighteen mandibles from human cadavers with a 4.5 cm paramedian L-type defect were reconstructed with bone from the iliac crest using 3 different osteosynthesis systems and continuously loaded on the "Mandibulator" test bench. Six mandibles each had the bones joined together using 2 monocortical non-locking plates, 2 monocortical locking plates, or a single bicortical locking plate/fracture gap. Macroscopic deformation, failure mechanisms, and movement of the fracture gap in all 3 dimensions were assessed and quantified over increasing loading by PONTOS(®) optical measurement systems. Final mechanisms of failure were excessive deformation of the plate, fracture of the mandibular fragments, and failure of the iliac crest graft. The plate became deformed mainly in the miniplate group. The iliac crest graft failed in all the specimens in which osteosynthesis was performed by a 6-hole TriLock(®) plate. Interfragmentary movement was minimised in the miniplate group. All three osteosynthesis systems provided sufficient stability for reconstruction when mechanically loaded up to 100 N. The miniplate allowed less movement in the gap and gave better stability than the two TriLock(®) plate systems. The superiority of the miniplate was significant when compared with the 4-hole TriLock(®) plate. The transplant failed mainly in the 6-hole TriLock(®) group, which suggests that the iliac crest graft works better with the miniplate as a more malleable osteosynthesis system.

Evaluation of a new optical measuring system for experiments on fractured human mandibles: a biomechanical feasibility study in maxillofacial surgery.

OBJECTIVES: Biomechanical loading on human mandibles was performed and a new optical measurement device was introduced for the quantification of interfragmentary movement in fractured mandibles stabilized with different osteosynthesis systems. MATERIALS AND METHODS: Comparison tests were performed with monocortical non-locking double plates and bicortical single locking plate. For the experiments on a specialized test bench, 18 ex vivo fractured human cadaveric mandibles were tested. Interfragmentary motion was detected in all three spatial dimensions using the optical measurement device PONTOS®. The movement was investigated over increasing incisal force and one summarized parameter was investigated. RESULTS: For the maximal tested load of 300 N m, the resultant interfragmentary movements in the two investigated groups were 2.96 ± 1.85° for the fixation with two conventional miniplates (six hole, profile 1.0 mm) and 4.53 ± 2.49° for single bicortically fixed locking plates (four hole, profile 1.5 mm). For both plate systems, we used the 2.0 mm screw system. CONCLUSIONS: The test bench in combination with the new optical device PONTOS(®) can test the primary stability of osteosynthesis. We offer a solution to the problem of rate of twist of the mandible as well as typical rotational problem in recent measurements. Further, the method can be used for development of new osteosynthesis products. CLINICAL RELEVANCE: Pseudoarthrosis formation is a common problem based on unsatisfying fixation of the fracture gap. The here presented combination of mechanical tests and numerical simulations can provide support for an improved treatment of fractured mandibles.

Prevalence of mistreatment and justice of grading system in five health related faculties in Jordan University of Science and Technology.

BACKGROUND: Many Jordanian university students complain of the behavior of some teaching staff. Also, they complain of the grading systems in universities. AIM: This study concerns the occurrence of different forms of student mistreatment and student mistrust of the grading system in the Jordan University of Science and Technology (JUST) as an example of universities in Jordan. METHOD: A total of 500 students in five health related faculties in JUST responded to a questionnaire. RESULTS: Our results were as follow: (i) 61% of the students had experienced at least one form of mistreatment; (ii) perceived mistreatment most often (52%) had taken the form of psychological mistreatment (shouting and humiliation); (iii) other forms of mistreatment such as physical harm (32%), mistreatment related to religion (36%), mistreatment related to external appearance (35%), sexual harassment (33%) and mistreatment related to specialty (29%) were also common; (iv) with the exception of mistreatment related to specialty which was high among the nursing students, perceived mistreatment did not vary significantly between the different faculties; (v) the male students (66%) complain more than female students (56%); (vi) perceived mistreatment was exceptionally high among the Israeli Arabs, 83% compared to 59% for the Jordanians and 65% for other non-Jordanian Arabs; (vii) fellow students (44%), professors (37%) and laboratory technicians (19%) were cited as major sources of mistreatment. Many students (66%) believe that grading system in JUST is unfair. Ninety seven percent of the Israeli Arabs did not trust the grading system compared to 64% of the Jordanians and 66% of the non-Jordanian Arabs. CONCLUSIONS: This study suggests that, feelings of mistreatment among university students is strong while their trust of the university grading system is low. Perceived mistreatment and an unfair grading system may be a major source of stress among our students and may affect the process of teaching and learning in our country. This should alert the university administration to face these issues and try to solve them.

Ovariectomy augments B lymphopoiesis and generation of monocyte-macrophage precursors in rat bone marrow.

To investigate the effects of estrogen depletion on hematopoiesis and bone turnover, female rats were either ovariectomized (OVX) or sham operated and killed at 1, 2, 3, and 4 wk postsurgery. Flow cytometric analysis of bone marrow cells (BMC) revealed that, in close temporal association with the rise in bone turnover as measured by bone histomorphometry, the number of Thy 1.1+ and KiB1R+ BMC increased two- to threefold in OVX rats relative to sham controls. The Thy 1.1+ BMC were further characterized as Thy 1.1+/KiB1R+ and Thy 1.1+/HIS24+ double-positive cells of the B cell lineage. A transient rise in ED1+ myeloid cells expressing a lysosomal antigen specific for the monocyte-macrophage and osteoclast lineage coincided with the upregulation of osteoclast numbers in OVX rats at 2 wk postsurgery, but the number of ED8+ myelomonocytic BMC remained unchanged. Administration of estradiol prevented the rise in Thy 1.1+, KiB1R+, and ED1+ BMC in OVX animals. Our study indicates that ovariectomy upregulates B lymphopoiesis in rat bone marrow and increases myeloid cell differentiation into the monocyte-macrophage and possibly also the osteoclast lineage.

[Step height measurement in the micrometer range by two-ray interferometry with adjustable light wavelength (author's transl)]. / Stufenhöhenmessung im Mikrometerbereich durch Zweistrahlinterferometrie mit einstellbarer Lichtwellenlänge.

The interferometric measurement of abrupt surface steps in the micrometer range requires additional means to give unique results. It will be shown, that advantageous interpretation of the interferometric fringes are possible by combining a two-ray interferometer with a monochromator.