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Fractures of the mandibular condyle account for a significant proportion of mandibular fractures. The specific functional loads require particular specifications for the implant design used for open reduction and internal fixation of such fractures. The clinical and radiographic outcomes in patients treated using a single rhombic 3D condylar fracture plate for open reduction and internal fixation at a single institution, and who fulfilled the inclusion and exclusion criteria, are presented. The primary outcome variables were: occlusion, maximum interincisal distance and mandibular excursion at 1, 3, and 6 months postoperatively, and radiographic measurements for mandibular height and gonion angle. In total, 263 patients were included, of whom 173 (65.8%) were male and 90 (34.2%) female. The mean age was 40.4 ± 18.9 years. There was satisfactory occlusion in 98.9% of patients at the 6-month follow-up, and a significant improvement in all parameters for mandibular excursion (p < 0.001), with a reduced ramus height and an increase in the gonion angle on the fractured side. Excellent clinical and radiographic results were achieved using the rhombic-shaped implant, deeming it appropriate for the osteosynthesis of mandibular condyle fractures., Competing Interests: Declaration of competing interest The authors have no direct or indirect interests relating to the work submitted for publication, including any financial or non-financial interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

There have been unprecedented advances in the identification of new treatment targets for chronic hepatitis B that are being developed with the goal of achieving functional cure in patients who would otherwise require lifelong nucleoside analogue treatment. Many of the new investigational therapies either directly target the immune system or are anticipated to impact immunity indirectly through modulation of the viral lifecycle and antigen production. While new viral biomarkers (HBV RNA, HBcAg, small, middle, large HBs isoforms) are proceeding through validation steps in clinical studies, immunological biomarkers are non-existent outside of clinical assays for antibodies to HBs, HBc and HBe. To develop clinically applicable immunological biomarkers to measure mechanisms of action, inform logical combination strategies, and guide clinical management for use and discontinuation of immune-targeting drugs, immune assays must be incorporated into phase I/II clinical trials. This paper will discuss the importance of sample collection, the assays available for immunological analyses, their advantages/disadvantages and suggestions for their implementation in clinical trials. Careful consideration must be given to ensure appropriate immunological studies are included as a primary component of the trial with deeper immunological analysis provided by ancillary studies. Standardising immunological assays and data obtained from clinical trials will identify biomarkers that can be deployed in the clinic, independently of specialised immunology laboratories., Competing Interests: Conflict of interest Please refer to the accompanying ICMJE disclosure forms for further details., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

The current surgical techniques used in cleft repair are well established, but different centers use different approaches. To determine the best treatment for patients, a multi-center comparative study is required. In this study, we surveyed all craniofacial departments registered with the German Society of Maxillofacial Surgery to determine which cleft repair techniques are currently in use. Our findings revealed much variation in cleft repair between different centers. Although most centers did use a two-stage approach, the operative techniques and timing of lip and palate closure were different in every center. This shows that a retrospective comparative analysis of patient outcome between the participating centers is not possible and illustrates the need for prospective comparative studies to establish the optimal technique for reconstructive cleft surgery., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: Approximately one quarter of persons exposed to hepatitis C virus (HCV) will spontaneously clear infection. We undertook this study to investigate the impact of alcohol on likelihood of HCV spontaneous viral clearance stratified by sex groups., Methods: Pooled data from an international collaboration of prospective observational studies of incident HIV and HCV infection in high-risk cohorts (the InC3 Study) was restricted to 411 persons (or 560.7 person-years of observation) with documented acute HCV infection and data regarding alcohol use. The predictor of interest was self-reported alcohol use at or after estimated date of incident HCV infection and the outcome was HCV spontaneous clearance. Sex stratified Cox proportional hazards models were used to evaluate the association between alcohol and spontaneous clearance, adjusting for age, race/ethnicity, and IFNL4 genotype., Results: The median age was 28.5 years, 30.4% were women, 87.2% were white, and 71.8% reported alcohol use at or after incident infection. There were 89 (21.6%) cases of spontaneous clearance observed, 39 (31.2%) among women and 50 (17.5%) in men (p<0.01). Overall, spontaneous clearance occurred less frequently among participants who drank alcohol compared to those who did not drink (18.9% v. 28.5%, p=0.03). After adjustment for other covariates, alcohol was significantly and independently associated with lower relative hazards for spontaneous clearance of HCV in women (AHR=0.35; 95% CI: 0.19-0.66; p=0.001) but not in men (AHR=0.63; 95% CI: 0.36-1.09; p=0.10)., Conclusion: Results indicate that abstaining from drinking alcohol may increase the likelihood of spontaneous clearance among women., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Transmission of HIV across mucosal barriers accounts for the majority of HIV infections worldwide. Thus, efforts aimed at enhancing protective immunity at these sites are a top priority, including increasing virus-specific antibodies (Abs) and antiviral activity at mucosal sites. Mucin proteins, including the largest cell-associated mucin, mucin 16 (MUC16), help form mucus to provide a physical barrier to incoming pathogens. Here, we describe a natural interaction between Abs and MUC16 that is enhanced in specific disease settings such as chronic HIV infection. Binding to MUC16 was independent of IgG subclass, but strongly associated with shorter Ab glycan profiles, with agalactosylated (G0) Abs demonstrating the highest binding to MUC16. Binding of Abs to epithelial cells was diminished following MUC16 knockdown, and the MUC16 N-linked glycans were critical for binding. Further, agalactosylated VRC01 captured HIV more efficiently in MUC16. These data point to a novel opportunity to enrich Abs at mucosal sites by targeting Abs to MUC16 through changes in Fc glycosylation, potentially blocking viral movement and sequestering the virus far from the epithelial border. Thus, next-generation vaccines or monoclonal therapeutics may enhance protective immunity by tuning Ab glycosylation to promote the enrichment of Abs at mucosal barriers.

Even though modern surgical techniques are dominating reconstructive facial procedures, the capability to use facial epitheses for reconstruction is still an important skill for the maxillofacial surgeon. We present an international multicenter analysis to clarify which techniques are used to fixate facial prostheses. We contacted all maxillofacial departments in Germany, Austria, Switzerland and Norway which were registered with the German society for oral and maxillofacial surgery (DGMKG). These centers were asked via electronical mail to provide information on the type of epithesis fixation systems currently in use. The return rate from 58 departments was 43.1% (n = 25). Overall, implant fixation was the preferred fixation system (92%). Plates were the second most common fixation technique (32%). No centers reported the standard use of non-invasive fixation techniques for permanent epithesis fixation. The main retention systems in use were magnets (24/25), other retention systems are used much less often. The current preferred fixation technique for facial epitheses consists of implant-based, magnet-fixated epitheses. For nasal prostheses, a plate-based, magnet-fixated system is often used., (Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Unlabelled: The development of sufficient tissue engineered bone grafts for alveolar cleft osteoplasty could reduce the necessity of autogenous bone grafts and its donor site morbidity. The aim of the study was to evaluate tissue engineered bone grafts in an artificially created bone defect. Bone grafts were created in vitro colonizing a synthetic hydroxyapatite-tricalciumphosphate scaffold (BONITmatrix(®)) with either undifferentiated mesenchymal stromal cells (group 1) or osteogenic differentiated mesenchymal stromal cells (group 2). Cells were multiplied from bone marrow of donor rats. Unmodified scaffolds (group 3) and the tissue engineered bone grafts were inserted into artificial maxillary defects of 54 Lewis rats. In 18 animals the defects remained unfilled (control). After one, three and six weeks the rats were sacrificed. The defect was evaluated radiologically and histologically with regard to the remaining defect volume and diameter. Statistical analysis followed. The bone grafts led to a specific bone formation at the defect margin. No complete reunion of any defect was observed within the healing time. After six weeks, the remaining defect volume was 6.86 ± 3.21 mm(3) (control), 4.08 ± 1.36 mm(3) (group 1), 5.00 ± 0.84 mm(3) (group 2) 5.50 ± 1.05 mm(3) (group 3). The remaining defect diameter measured 2.63 ± 0.52 mm (control), 2.39 ± 0.23 mm (group 1), 2.53 ± 0.22 mm (group 2) and 2.70 ± 0.66 mm (group 3). In all experimental groups the defect volume and diameter decreased over time, which was significant for group 1 (p = 0.014), group 2 (p = 0.025) and group 3 (p = 0.048). The defect volume and width was significantly reduced for bone grafts containing undifferentiated cells compared to control (p = 0.035) or scaffolds only (p = 0.05)., Conclusion: Tissue engineered bone grafts induce a pronounced bone formation in artificial bone defects compared to unfilled controls or scaffolds only., (Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Objectives: The reconstruction of mandibular continuity defects by bridging plates often leads to complications. Customized mandibular implants might be an alternative option. In the present study, the stability at the bone-implant-interface of customized two-piece implants was compared to one-piece implants., Methods: Thirty pig mandibles were randomly divided into three groups. One group (A) was left untreated and served as reference. In groups B and C, a continuity defect was created in the left mandibular side. The defects were reconstructed by customized pure titanium implants, manufactured using the LaserCUSING(®) technology. Group B received a one-piece implant; in group C a two-piece implant was inserted to reconstruct the continuity defect. The bonding strength was examined statically and dynamically under standardized conditions. Digital Image Correlation was used for distortion measurement. Different dynamic measurements were performed for orientation purposes., Results: The highest bonding strength was measured for the reference group. The two-piece implant showed an increased bonding strength when compared to the one-piece design. In all pig mandibles treated with individual implants a fracture occurred on the non-operated side. This indicates a high primary stability of the bone-implant-interface., Conclusion: The two-piece individual mandibular implant manufactured by LaserCUSING(®) technology should be further analyzed in future studies., (Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: This retrospective study comprises an exploratory analysis of 10 years of surgical treatment of symphysis (S) and parasymphysis/body (P/B). Correlations of complications, as well as dependencies of surgical concepts, are investigated., Materials and Methods: All surgically treated patients in the period of 1995 to 2005 with at least one mandibular fracture mesial to the mandibular angle were included in this study. A total of 63 patients (46 men, 17 women) with 63 symphysis fractures were included and 497 patients (369 men, 128 women) with 553 P/B were included; 99.27% (549) of these fractures were included in the study, 4 had to be dismissed because of inconclusive documentation., Results: Of patients with P/B, 96.04% were successfully treated with 1 open reduction, 3.76% had 2, and 0.20% had 3 surgeries. Of the surgically treated patients, 75.77% (416) were completely free of complications, whereas the other 24.23% of the P/B showed 1 or more complications. The main complication was mild nerve damage (24.8%). Osteosynthesis failure rate (OFR) was 2.4% (7 of 298) for 2 miniplates, 5.7% (3 of 53) for 1 tension screw, and 8.4% (9 of 107) for 1 miniplate. Regarding OFR, 2 miniplates showed to be superior in a Fisher exact test (P = .018, adjusted P = .132). Symphysis fractures were completely free of complications in 81.8% and showed 2 major complications, i.e., 1 severe nerve damage and 1 osteosynthesis failure., Discussion: This study has the limitations of a retrospective study., Conclusion: A high success rate of open reduction and osteosynthesis with 2 miniplates can be guaranteed., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Background: Osteosynthesis failure rates of 11.3% with 1 miniplate, 6.7% with 2 miniplates, and 4.4% with a single Medartis condyle plate were reported in previous studies of our clinic. Current science is still focused on the osteosynthesis material. Besides clinical parameters, conventional radiographs are still the first choice to detect osteosynthesis failures. This study scrutinized several factors assessable in postoperative orthopantomographs which might elevate the risk of osteosynthesis failure., Study Design: A total of 136 patients (22 with osteosynthesis failure, 114 without) with 151 mandibular condyle fractures were included in this study. Eight parameters were assessed in postoperative orthopantomographs., Results: The best predictor of osteosynthesis failure was a simplified concept of ramus height. In cases of reduced or normal ramus height, the odds of osteosynthesis failure was significantly (P = .000001) reduced to a 10th. Isolated fractures were significantly more error prone (P = .0009)., Conclusions: Postoperative orthopantomographs depict factors which increase the risk of osteosynthesis failure., (Copyright © 2011 Mosby, Inc. All rights reserved.)

To bridge the cleft in the alveolar bone and to allow for physiologic eruption of the canine teeth, alveolar bone grafting is often necessary in patients with cleft lips and palates. Instead of autogenous bone, biomaterial seeded with autogenous osteogenic cells has found some clinical application. However, so far no real functional proof has been available to demonstrate that this technique also allows further physiologic features such as tooth eruption to occur. This report describes the results of grafting tissue-engineered bone into the alveolar cleft of a 10-year-old boy. Immediate postoperative healing was uneventful. Eight months after grafting, erupting teeth had moved into the newly formed bone. Eighteen months postoperatively at the site where the tissue-engineered graft had been inserted, the canine had erupted spontaneously in its proper place. The data suggest that tissue-engineered bone can lead to the ossification of the alveolar cleft and allow for physiologic spontaneous tooth eruption.

Aim: While functionally stable osteosynthesis is a generally accepted method to treat all dislocated fractures of the skull, open reduction and rigid fixation of fractures of the mandibular condyle are still controversial. The risks involved in the surgical approaches and the difficulties during reposition are the main controversies. Improvements made in surgical access and osteosynthesis materials as well as the development of special instruments were the reasons for re-evaluating the surgical results., Methods: Forty patients with displaced or dislocated fractures of the mandibular condyle were re-examined. In 20 patients (21 fractures) an intraoral approach, in 20 more patients (24 fractures) an extraoral perimandibular approach was applied. The results were compared by means of axiography and radiology as well as clinically with regard to function 6 months postoperatively., Results: While almost all fractures were correctly reduced following application of an extraoral access, reduction was correct in only 50% of the patients treated with an intraoral approach. Re-displacement and complications during osteosynthesis were the reasons. The group of patients treated via the intraoral approach showed less favourable results radiologically, clinically, and as judged by the patients' subjective feelings. Especially axiographical examination of the latter fractures revealed a restricted translation indicating that the fractures had not healed primarily., Conclusion: In order to avoid complications, the only fractures which should be treated intraorally are those which allow exact reduction even under the conditions of a limited view and reduced possibilities of surgical manipulation during reduction. This applies in general to fractures of the mandibular condyle with a laterally displaced condyle and a shortened ascending ramus. For all other dislocated or displaced fractures, extraoral reduction and osteosynthesis are the methods of choice.

Purpose: Gingival hyperplasia is a well known side effect of Cyclosporine A therapy. The aetiology of this is not totally understood and there is debate whether it is hyperplasia of the gingival epithelium or of the submucosal connective tissue, or both, and what roles play factors like age and gender of the patients, duration and dosage of the drug., Material and Methods: The influence of different Cyclosporine A concentrations (10(-6) g/ml; 5 x 10(-7) g/ml; 10(-9) g/ml) and of no medication (controls) on growth and proliferation of cultured human gingival keratinocytes was investigated after a culture period of 3, 6 and 9 days. Cell proliferation was assessed by counting anti Ki-67 stained nuclei, cell growth by counting total number of nuclei and by the EZ4U-assay., Results: There was no significant correlation of the cell proliferation rate and cellular growth with either gender (p > 0.568) or duration of medication (p > 0.876); but Cyclosporine A concentration showed a highly significant influence on cellular growth (p = 0.0001). Inhibition of cell growth was dependent on drug dosage, but a low concentration of 10(-9) g/ml even stimulated cell growth., Conclusions: There is evidence that Cyclosporine A in low concentrations (10(-9) g/ml as applied in long-term therapy) stimulates gingival keratinocyte growth and therefore might be related to hyperplasia of the gingiva. However, high Cyclosporine A concentrations may inhibit cell growths and factors like gender of the patient did not show any influence in-vitro.

Introduction: Surgical correction of malocclusion changes the force to moment ratio of masticatory muscles inserting at the mandible caused by shortening, lengthening and rotation of the bone following osteotomy. During muscle adaptation the expression of mRNA for the myosin heavy chain (MyHC) of type I and type II fibres may be changed., Material and Methods: The adaptation of the masseter muscle was investigated at the mRNA level in 10 patients 6 months after orthognathic surgery in the mandible. The competitive polymerase chain reaction (cPCR) is a suitable method for quantification of MyHC mRNA. For application of this minimal invasive method an amount of 35 mg muscle tissue was sufficient., Results: 6 month postoperatively there was a deficiency of about 87% of MyHC mRNA for fibre type I and II in both groups of patients. The deficiency in patients with mesial position of the mandible was higher but not significant different to patients with distal malocclusion., Conclusion: Patients should use the postoperative interval for training their masticatory muscles. This improves the stability of treatment result and prevents relapse.

Purpose: The aim of this study was to evaluate the ectopic bone formation using tissue engineered cell-seeded constructs with two different scaffolds and primary human maxillary osteoblasts in nude rats over an implantation period of up to 96 days., Material and Methods: Collagen I-coated Poly(3)hydroxybutyrate (PHB) embroidery and hydroxyapatite (HAP) collagen tapes were seeded with primary human maxillary osteoblasts (hOB) and implanted into athymic rnu/run rats. A total of 72 implants were placed into the back muscles of 18 rats. 24, 48 and 96 days after implantation, histological and histomorphometric analyses were made. The osteoblastic character of the cells was confirmed by immunocytochemistry and RT-PCR for osteocalcin., Results: Histological analysis demonstrated that all cell-seeded constructs induced ectopic bone formation after 24, 48 and 96 days of implantation. There was more mineralized tissue in PHB constructs than in HAP-collagen tapes (at day 24; p < 0.05). Bone formation decreased with the increasing length of the implantation period. Osteocalcin expression verified the osteoblastic character of the cell-seeded constructs after implantation time. No bone formation and no osteocalcin expression were found in the control groups., Conclusions: Cell-seeded constructs either with PHB embroidery or HAP-collagen tapes can induce ectopic bone formation. However, the amount of bone formed decreased with increasing length of implantation.

Purpose: In this study the efficacy of computer-assisted surgery (CAS) used for secondary orbital reconstruction after midfacial fractures was evaluated, comparing the clinical outcome with that after conventional surgery (CS). Special consideration was given to whether CAS can reduce the number of secondary corrections., Patients and Methods: Twenty consecutive patients (24 orbits; 12 in each group) were assessed for enophthalmos, diplopia, and aesthetics during a follow-up period of up to 3 years., Results: After CAS, enophthalmos was fully corrected in 8 of 11 orbits but after CS in only 6 of 10 orbits. Improvement of diplopia was achieved in 1 of 7 (CAS) and in 3 of 4 (CS) patients. The aesthetic result after secondary reconstruction and additional surgery was better in the CAS group. Additional surgery to correct bony structures was only necessary in 3 patients of the CS group. Additional soft tissue surgery was necessary in both groups., Conclusion: CAS can improve the clinical outcome of reconstructive bone surgery reducing the amount of additional hard tissue procedures. It was helpful during dissection of the scarred orbital tissue and placement of a graft. However, it had no impact on soft tissue correction especially with respect to function.

Objective: The aim of this study was to compare bone regeneration after grafting enucleated mandibular cyst cavities using either autogenous osteoblasts cultured on a biomaterial or autogenous spongiose iliac bone., Study Design: Twenty patients with 22 mandibular cysts were assessed. Eleven cysts were filled in with tissue-engineered bone (autogenous osteblasts cultured on demineralized bone matrix Osteovit) and 11 with spongiose iliac bone as controls. Panoramic radiographs were taken preoperatively, immediately postoperatively, and 3, 6, and 12 months after surgery. Radiolucency was computer analyzed using gray-level histograms., Results: In both groups bone regeneration took place in a similar fashion. After 3 and 6 months there were few differences in bone density between the groups. However, in radiographic controls after 12 months ossification was considerably stronger in cysts grafted with tissue-engineered bone., Conclusion: These results advocate for the clinical application of tissue-engineered bone as an alternative viable filling material for cysts.

Introduction: Non-syndromic cleft lip with or without cleft palate (CL/P), is one of the most common birth defects, but its aetiology is largely unknown. The aim of this study was to determine the sequence changes of the Cleft Lip and Palate Transmembrane Protein 1 (CLPTM 1) and Poliovirus Receptor Related 1 (PVRL 1) genes in patients with non-syndromic complete clefts of lip, alveolus and palate and to correlate these findings with clinical features., Patients and Methods: 25 patients were analysed (14 male and 11 female, aged 4-10 years) of European descent (9 patients with right, 9 with left and 7 patients with bilateral CLAP) and 25 controls, respectively. Exons 2-14 of the CLPTM1 and exons 1-6 of the PVRL1 gene were analysed by a direct sequencing method using DNA extracted from whole blood., Results: A novel in frame Glu441-Gly442 ins Glu mutation of the PVRL 1 gene in combination with novel exon mutations Gly331Gly, Ala88Ala, Pro309Pro and intron change IVS7-10G/A of the CLPTM 1 gene were found in 9 patients. The Glu441-Gly442 ins Glu mutation and the intron change IVS7-10G/A were not detected in 25 controls., Conclusion: These results suggest that a simultaneous occurrence of PVRL1 and CLPTM 1 gene mutations in cleft patients does not correlate with the type of cleft (left, right, bilateral) or the gender of the patients. If a combination of the intron change IVS7-10G/A, exon changes Gly331Gly, Ala88Ala and Pro309Pro of the CLMPT 1 gene and Glu441-Gly442 ins Glu mutation of the PVRL 1 gene could be a genetic factor for non-syndromic clefts of the primary and the secondary palates, it is important to investigate more patients and controls.

Aim: To simulate the surgery of dysgnathia, several forms of computer software allowing two-dimensional 'virtual' planning are frequently used. However, in many cases it is not possible to transfer the virtual plan accurately to the surgical site. It is the purpose of this study to find the errors likely to occur when transferring the data., Methods: In 22 bimaxillary osteotomies for dysgnathia, the results of preoperative planning were compared with the surgical outcomes. The programme WinCeph 4.19 (Compudent) was used for cephalometric analyses and simulation of the operations., Results: Six major skeletal parameters were evaluated when comparing both the planned and the actual outcome, and the following results were recorded: Delta-SNA 1.53 degrees (+/-1.20), Delta-SNB 1.67 degrees (+/-1.29), Delta-ANB 1.62 degrees (+/-1.47), Delta-NL-NSL 3.9 degrees (+/-2.30), Delta-ML-NSL 3.6 degrees (+/-3.7) and Delta-ArGoMe 6.1 degrees (+/-4.6)., Conclusion: It was anticipated that the most important differences between planned and surgical outcomes were found to be in the vertical changes. Planning and data transfer was comparatively accurate with regard to sagittal data. Apart from several mechanical methods for data transfer, systems using navigation are therefore being discussed and used increasingly. They ensure accurate data transfer to the surgical site.

Aim: The purpose of this study was to compute the load on different osteosynthesis plates in a simplified model using finite element analysis, and to find out whether miniplates were sufficiently stable for application at the mandibular angle., Patients: Data from 277 patients with 293 fractures of the mandibular angle have been evaluated., Methods: A computation model using finite elements was established in order to compute mechanical stress occurring in osteosynthesis plates used for fixation of fractures of the mandibular angle. In the second part of this study, the data from all in-patients treated for fracture of the mandibular angle were evaluated retrospectively. Age and sex of the patients, cause of fracture, state of dentition, type of therapy as well as complications were noted., Results: In those tests, both the 1.0 mm miniplate and the 2.3 mm module plate were sufficiently stable. The rate of major complications (requiring revisional surgery with general anaesthesia) amounted to approximately 17% in comminuted fractures, or in non-compliant patients in which primary stability with a single miniplate did not appear sufficient, so that other osteosynthesis methods were used in addition. This rate was considerably higher than that in simple mandibular fractures. Simple fractures of the mandibular angle were just treated with one miniplate following Champy's guidelines strictly. In these fractures the rate of major complications was only 2.3%., Conclusion: In comminuted fractures and in non-compliant patients, the use of a stronger osteosynthesis material should be considered while in all other cases application of a single 1.0 mm miniplate was regarded as sufficient for fixation using open reduction.

Introduction: There are reports that thrombosis in microsurgically anastomosed vessels occurred after the vessels were drawn into the suction drains., Aim: To study the effects of suction drainage on microvascular anastomosis., Patients and Methods: The authors compared the proportion of complications in 77 patients who had suction drainage (n=45) or no suction drainage (n=32) with microvascular free flap surgery in the head and neck region. Ultrasonography and Doppler flow ultrasonography were performed on five more patients 3 days after the operation., Results: There were no significant differences between the two retrospectively evaluated groups for incidence of postoperative complications. Ultrasound in the prospective study group revealed that vessels were neither sucked into the suction drain nor displaced towards the drain., Conclusion: These findings contravened the reports of vessels being sucked into drains and therefore the clinical use of suction drainage in conjunction with microsurgery in the head and neck region is still advocated., (Copyright 2001 European Association for Cranio-Maxillofacial Surgery.)

Objective: A prospective study was designed to compare computer-aided 3-D 99mTc-DPD-SPECT (Technetium-Dicarboxy propan-single photon emission CT) reconstruction with clinical examination, panoramic radiography, CT scan and conventional 99mTc-DPD-SPECT investigation in the assessment of mandibular bone invasion by squamous cell carcinoma., Patients and Methods: Between October 1997 and December 1999, 88 patients with intraoral squamous cell carcinoma of the regions adjacent to the mandible were enrolled in this study. In 50 cases, mandibular resection (segmental or marginal) was performed based on the pre-treatment diagnostic results. Imaging studies were read independently by four experienced observers., Results: No differences could be found between presurgical 3-D 99mTc-DPD-SPECT reconstruction and conventional 99mTc-DPD-SPECT investigation. Both techniques revealed a sensitivity of 100% whereas CT scan showed the greatest specificity (93.8%). SPECT investigation had a specificity of 91.6% and the greatest efficiency (95.4%). The greatest predictive positive value was found for CT scan (92.3%). Clinical examination and panoramic radiography displayed the lowest sensitivity, 82.5% vs. 85.0%, and specificity, 79.2% vs. 89.5% respectively., Conclusion: This investigation does not provide evidence that 3-D 99mTc-DPD-SPECT reconstruction has any advantages when compared to conventional 99mTc-DPD-ECT investigation in the assessment of mandibular invasion by squamous cell carcinoma. Despite a sensitivity of 100% the specificity is still in need of improvement. Until newer methods or techniques become available the combination of CT scanning and conventional 99mTc-DPD-SPECT investigation appears to be the best means of detecting tumour invasion preoperatively and is thus helpful in directing appropriate surgical procedure.

Objective: We conducted a prospective investigation to evaluate the diagnostic accuracy of computer-aided 3-dimensional (3-D) technetium 99m dicarboxypropane methylene diphosphonate ((99m)Tc-DPD) single photon emission computed tomography (SPECT) reconstruction in the evaluation of microvascular bone flaps used for maxillofacial reconstruction., Study Design: Twenty patients who received 20 autogenous microvascular bone flaps for reconstruction of the mandible and maxilla were evaluated. Forty bone scans with subsequent computer-aided reconstruction were performed. Each graft could be assessed within 48 to 72 hours after surgery. The second bone scan was performed between 12 and 14 days after surgery., Results: Complications were observed in 5 grafts. SPECT investigation performed at the 2 time points after reconstruction showed a significantly higher tracer uptake in grafts with an uncomplicated further course than in those that developed complications., Conclusions: Computer-aided 3D (99m)Tc-DPD SPECT reconstruction serves as a useful prognostic tool and helps in the very early recognition of complications. This technique adds significantly to the value of planar bone scintigraphy and conventional SPECT images.

Degradation of angiogenic mediators might be an underlying cause of chronic wounds. To test this hypothesis, we evaluated the expression and integrity of vascular endothelial growth factor, a potent angiogenic mediator, and its receptors, Flt-1 and KDR, in chronic venous leg ulcerations. Immunohisto- chemical, in situ hybridization, and semiquantitative reverse transcriptase polymerase chain reaction analyses all indicate that expression of vascular endothelial growth factor is elevated in ulcerative tissue, with vascular endothelial growth factor mRNA being especially pronounced in the hyperplastic epithelium of the wound margin. Flt-1 and KDR protein and mRNA were detected in the papillary vessels in close vicinity to the lesional epithelium of chronic wounds. Although increased expression of vascular endothelial growth factor protein was detected in the epidermis, the intensity of this staining was weak compared with the epidermal staining in psoriatic lesions and compared with the strong vascular endothelial growth factor mRNA signal in chronic wounds and psoriasis. To analyze whether this apparent decrease in immunoreactivity could be the result of degradation of vascular endothelial growth factor by proteolytic activities from the wound environment, we examined the stability of recombinant vascular endothelial growth factor in wound fluid from chronic leg ulcers. As demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, incubation of rVEGF165 with chronic, but not acute, wound fluid resulted in rapid proteolytic degradation of rVEGF165. Protease inhibitor studies indicate that serine proteases, such as plasmin, are involved in this degradation. Together, our data show that, although vascular endothelial growth factor expression is elevated in chronic wounds, increased proteolytic activity in this environment results in its degradation, which may contribute to an impaired wound healing response.

Background/aims: Immune-mediated mechanisms are believed to play an important pathogenetic role in chronic hepatitis C virus infection. Interleukin 4 (IL-4) and IL-10 are secreted by T helper-2 type cells (Th2) which may downregulate cell-mediated immune effector mechanisms important in the host defense against intracellular pathogens. This study aimed to determine Th2 cytokine levels in chronic hepatitis C virus infection., Methods: Serum IL-4 and IL-10 levels were measured in 74 patients with chronic hepatitis C virus infection and 20 healthy controls. The expression of CD30 in liver, a marker that is preferentially expressed in Th2 cells, was also determined by immunohistochemical staining in 37 patients., Results: Serum IL-4 and IL-10 were below the detection limit (5 pg/ml) in all 20 healthy controls. However, 36 patients (49%) had elevated serum IL-4 levels (range 5-106 pg/ml, p<0.001) and 23 patients (31%) had elevated serum IL-10 levels (range 5-37 pg/ml, p<0.05). There was no correlation between serum IL-4 and IL-10 levels. There was also no correlation between serum IL-4 and IL-10 levels and any of the clinical (age, gender, mode of acquisition), biochemical (serum alanine transaminase levels), virologic (viremia level, genotype), and histological parameters examined. Twenty of 37 liver biopsy specimens from patients with chronic hepatitis C virus infection showed occasional CD30+ lymphocytes, suggestive of Th2 phenotype. However, in 20 of the 37 patients with paired cryostat liver sections, IL-4 was not detected in any of these patients, suggesting that IL-4 was not produced in the liver in patients with chronic hepatitis C virus infection., Conclusions: This study showed that serum Th2 cytokines are elevated (but at a low level) in a proportion of patients with chronic hepatitis C virus infection. However, the elevated Th2 cytokine levels may represent a systemic response and not a result of increased local production within the liver.

In oral and maxillofacial surgery an adequate mucosa/gingiva transplant is often not available in the amount required. Use of cultured gingival keratinocytes is a possibility in overcoming this problem. Keratinocytes were cultured in primary culture from gingival biopsies without xenogenous feeder-cells. The cells grew out of explants and formed, within 4 to 6 weeks, a sheet of keratinocytes up to size of 75 cm2. We have a success rate of 65% in cultures of people older than 40 years. This and the culture without feeder-cells encouraged us to use the cultured gingival cells as an autologous transplant in pre-prosthetic surgery for anterior vestibuloplasty.

In cultivating gingival epithelium from people up to the age of 66 years it is possible to gain a differentiated mucosal tissue sheet that is more than 100 times the size of the original biopsy surface. The morphological characteristics are a prickle cell layer with polygonal cells and a basal cell layer with flattened cells. Desmosomes, tonofibrils and microplicae at the superficial side of the epithelium are typical features. There is a cell biological differentiation as the distinct binding of lectins and of a cytokeratin antibody proves. The multiplication in surface area, the possibility of using cells of senior patients and the morphological and cell biological differentiation of cultured gingival epithelium are advantages in its application for the autologous bridging of intraoral defects.

In the present study, we were particularly interested in distinguishing specific patterns of structural and functional proteins in the collecting duct system of neonatal and adult kidneys and in cultured renal collecting duct epithelia in order to ascertain the degree of differentiation in the cultures. We studied the distribution of specific renal collecting duct cell markers using morphological, immunohistochemical and biochemical procedures. Cultured renal collecting duct epithelium undergoes maturation in vitro. Examples of morphological differentiation include the appearance of cilia and microvilli at the apical cell pole, and a basement membrane at the basal aspect of the epithelium. Tight junctions with five to seven strands separate the wide intercellular spaces from the apical cell surface. Physiological maturation from a 'leaky' to a 'tight' epithelium is evident from the acquisition of the alpha-subunit of Na/K-ATPase and the development of a high transepithelial potential difference and resistance. Biochemical differentiation is revealed by the expression of specific proteins. The simple-epithelium cytokeratins, PKK1 and PKK2, which are typical intracellular-matrix proteins of mature collecting duct epithelium, maintain the same distribution in cell culture as in neonatal and adult kidneys. An indicator of maturation in vitro is the expression of the collecting duct-specific proteins, PCD2 and PCD3. Newly developed monoclonal antibodies against these antigens reacted similarly with cultured cells and cells of the mature collecting duct system, but they did not label the embryonic ampullae in the cortex of neonatal rabbit kidneys. In contrast, a third collecting duct-specific protein, PCD1, is not expressed by the cultured cells, which indicates the retention of an embryonic characteristic in vitro. Embryonic collecting duct ampullae of the neonatal kidney in situ contain laminin during their development. Laminin is, however, absent in cultured collecting duct epithelium. Biochemical stimulation of the adenylate cyclase system by arginine vasopressin resulted in a twofold stimulation of the enzyme activity. This degree of stimulation is similar to that found in maturing kidneys of neonatal rabbits and indicates another embryonic feature of the cultures.