Perioperative anticoagulation in head and neck free flap reconstructions: Experience of an anticoagulative scheme and its modification.

OBJECTIVES: Microvascular anastomoses in microvascular reconstructions induce rheological changes in the anastomosed vessels and are usually counteracted by anticoagulative medication. There is no regimen commonly agreed on. This study provides an easy to use anticoagulative regimen. PATIENTS AND METHODS: Consecutive cases of either anticoagulative regimen between 2013 and 2018 that underwent microvascular reconstruction in the head and neck area were included in this retrospective study, resulting in 400 cases in total. Two different anticoagulative regimens were applied to 200 patients in each group: (a) intraoperatively administered unfractionated 5000 I.U. high molecular weight heparin (HMWH) and postoperatively low molecular weight heparin (LMWH, Enoxaparin) 1 mg/kg/body weight postoperatively and (b) intraoperatively LMWH 0.5 mg/kg/body weight as well as 12 h later and 1 mg/kg/body weight postoperatively. RESULTS: The LMWH cohort showed fewer overall thromboembolic (8.5% vs. 11%; p = .40) and peripheral thrombotic events (1% vs. 3.5%; p = .18) and lung embolisms (3% vs. 4%; p = .59). The number of thromboses at the site of the anastomosis was equally distributed. In regard to flap-specific complications, LMWH was associated with a positive effect, in particular with respect to total flap losses (5% vs. 7%; p = .40) and wound-healing disorders (14.5% vs. 20%; p = .145). CONCLUSION: Findings indicate that intra- and postoperatively administered LMWH as the only anticoagulative medication seems reliable in our clinical routine of head and neck free flap reconstructions.

Retrospective analysis of complications in 190 mandibular resections and simultaneous reconstructions with free fibula flap, iliac crest flap or reconstruction plate: a comparative single centre study.

OBJECTIVES: The purpose of this study was to evaluate the incidence of complications following mandibular reconstruction and to analyse possible contributing factors. MATERIALS AND METHODS: Clinical data and computed tomography scans of all patients who needed a mandibular reconstruction with a reconstruction plate, free fibula flap (FFF) or iliac crest (DCIA) flap between August 2010 and August 2015 were retrospectively analysed. RESULTS: One hundred and ninety patients were enrolled, encompassing 77 reconstructions with reconstruction plate, 89 reconstructions with FFF and 24 reconstructions with DCIA flaps. Cutaneous perforation was most frequently detected in the plate subgroup within the early interval and overall (each p = 0.004). Low body mass index (BMI) and total radiation dosage were the most relevant risk factors for the development of analysed complications. CONCLUSIONS: Microvascular bone flaps have overall less skin perforation than reconstruction plates. BMI and expected total radiation dosage have to be respected in choice of reconstructive technique. CLINICAL RELEVANCE: A treatment algorithm for mandibular reconstructions on the basis of our results is presented.

Alterations in Surgically Created Intimal Lesions: An Observation Study in the Aortic Rat Model.

BACKGROUND: Intimal injury in microvessels due to common risk factors such as atherosclerosis or inadequate manipulation are known to have a major impact on developing thrombosis and eventually vascular obstruction. Understanding of these injuries is therefore of great significance to prevent far-reaching consequences such as flap loss in free tissue transfer. It was the aim of this study to evaluate artificially induced intimal lesions with focus on alteration in size and configuration. METHODS: Intimal defects were created surgically in the abdominal aorta of 30 male Wistar rats. After planimetric measurement of the defect sizes, configuration of defects were classified as round, horizontal, or vertical. Seven days postoperatively, the rats underwent a second-look surgery. Finally, the abdominal aorta was harvested, and the endothelial defects were reevaluated concerning size and configuration using a defined pattern. RESULTS: The mean defect size created intraoperatively was 1.68 ± 0.6 mm2. The classification of the defects configurations resulted in 43.3% round, 20% horizontal, and 36.7% vertical defects. Reevaluation at 7 days after surgery showed defect shrinkage in 96.7% in total and 42.8% averaging due to reendothelialization. A shift in defect configuration was detected in 56.7%, the strongest being in vertical defect configurations (100%). Vascular occlusion did not occur in any of the specimen. CONCLUSION: Intimal injuries undergo a fast repair process in terms of size reduction and configuration modification due to reendothelialization. Especially vertical defects, representing a great risk for thrombus formation, convert into lower risk horizontal defect configurations. In high-flow vessels such as the rat aortas, small endothelial damage seems to have no significant impact to produce complete vascular occlusion. Still, all efforts should be made to avoid any kind of intimal injury.

Clinical performance of tooth- or implant-supported veneered zirconia single crowns: 42-month results.

OBJECTIVES: The objective of this clinical study was to compare and assess the clinical performance of tooth-supported and implant-supported zirconia single crowns with sintered veneering caps. METHODS: In this prospective study, 118 patients with a total of 220 single crowns placed on 106 teeth (69 vital teeth, 37 endodontically treated teeth) and 114 implants in molar and premolar regions were examined during a mean observation period of 42 months. The restorations were evaluated for technical failures such as veneering porcelain fractures (chipping), surface quality, marginal fit, and the interface quality of the coping and sintered veneering. The soft tissue status was assessed using the modified Silness and Löe's plaque and gingival index (mPI) and the modified Muhlemann sulcus bleeding index (mSBI). Tooth-supported crowns were checked for secondary caries and hypersensitivity during the follow-up period. Recalls were performed every 6 months. RESULTS: The 3-year Kaplan-Meier success probability was 98.2% and 100% for implant- and tooth-supported crowns, respectively. A significant difference could be detected between the implant-supported and tooth-supported zirconia single crowns, in terms of their chipping rate (p = 0.039). Veneering material fractures were recorded on two implant-supported restorations (1.8%). No veneering fractures occurred on tooth-supported single crowns. The plaque and gingival index and sulcus bleeding index showed stable and healthy soft peri-implant and periodontal tissues. Neither loss of vitality nor secondary caries occurred on tooth-supported crowns. CONCLUSIONS: Zirconia-based single crowns with a sintered veneering cap showed promising clinical results on both tooth and implant abutments; however, the dental implants were more prone to complications. In terms of clinical significance, high-strength ceramic with a sintered veneering cap can be recommended for prosthetic treatment of both tooth- and implant-supported single crowns in molar regions. CLINICAL RELEVANCE: This study provides valuable information for further application of all-ceramic restorations.

Effect of Segment Length and Number of Osteotomy Sites on Cancellous Bone Perfusion in Free Fibula Flaps.

BACKGROUND: Indocyanine green (ICG) videoangiography is routinely used to evaluate skin and organ perfusion and to assess patency rates of microvascular anastomoses. This study uses ICG angiography as a novel approach to qualitatively and quantitatively evaluate bone perfusion of microvascular fibula grafts intraoperatively and to assess the effect of fibula segment length and number of osteotomies on bone perfusion. METHODS: All patients planned for mandible reconstruction using a microvascular fibula graft between January 2013 and May 2017 were considered for this study. ICG videoangiography of cancellous bone perfusion was performed using a handheld ICG camera. Videos were analyzed, and a perfusion curve was generated. Peak enhancement, time to peak, slope, and wash-in area under the curve were extracted; rise time, wash-in rate (WiR), and wash-in perfusion index were calculated. Results were statistically analyzed with regard to distal fibula segment length and number of osteotomy sites. RESULTS: Thirty-nine patients (age 59 ± 8 years) were included in the study. Mandible reconstruction was achieved with 1 (n = 15), 2 (n = 13), or 3 (n = 11) fibula segments. The WiR was 6.4 ± 2.3 and 4.4 ± 0.2 before and after proximal osteotomy, respectively. The wash-in perfusion index was 114.2 ± 48.4 before and 84.4 ± 20.0 after proximal osteotomy. Bone perfusion was significantly reduced after additional proximal osteotomies. Both the segment length and number of proximal osteotomies correlated with bone perfusion, with longer segments and fewer osteotomies showing higher perfusion. CONCLUSION: This study demonstrates the feasibility of cancellous bone perfusion analysis using ICG and can serve as a basis for future bone perfusion studies. Additional osteotomies and short segment length negatively affects cancellous bone perfusion of the distal fibula segment in free fibula flaps. The extent to which the observed decrease in arterial inflow to the distal fibula segment affects the further course of healing needs to be addressed in future studies.

Dental implant surfaces after insertion in bone: an in vitro study in four commercial implant systems.

OBJECTIVES: Primary healing of dental implants is influenced by their surface morphology. However, little is known about any alterations in morphology during their insertion. Therefore, the aim of this study was to evaluate the surface morphology of four different implant systems, following their insertion in porcine jaw bones. METHODS: Four fresh porcine mandible specimens were used. Six new implants of four systems (Ankylos® 4.5 × 14 mm, Frialit Synchro® 4.5 × 15 mm, NobelReplace ® Tapered Groovy RP 4.3 × 13 mm, Straumann SLA® Bone Level 3.3 × 14 mm) were inserted, whereas one implant of each system served as a control. After their removal, implants were cleaned in an ultrasonic bath. All 28 implants were examined quantitatively by 3D confocal microscopy for surface characteristics. RESULTS: In the evaluated zones, implants of the Ankylos, Frialit, and Straumann systems showed mostly a reduction of the mean surface roughness Sa, the maximal surface roughness Sz, and the developed surface area ratio Sdr; Nobel implants showed an increase in these parameters. With respect to all three parameters Sa, Sz, and Sdr, statistical analysis revealed that differences between the four systems were highly significant in the apical region of implants. Controls showed no morphologic alterations. CONCLUSION: The insertion process had an impact on the surface of all four implant systems. Anodized implant surface modification seems to result in more alterations compared with subtractive surface modifications. Therefore, surgical planning should take into consideration the choice of surface treatment because the characteristics of the implants may be modified during the installation process. CLINICAL RELEVANCE: The given information is of value for daily implantation practice and the course of osseointegration.

Clinical performance of screw-retained and cemented implant-supported zirconia single crowns: 36-month results.

OBJECTIVES: The objective of this clinical study was to evaluate the clinical performance of implant-supported zirconia crowns with a sintered veneering cap. Furthermore, the influence of the type of retention (screw-retained vs cemented single crowns) was analysed. MATERIALS AND METHODS: Fifty-eight patients were accommodated with 114 implants, inserted in the molar and premolar regions. Zirconia-based crowns with a sintered veneering cap were either screw-retained (n = 53) or cemented (n = 61) on the implant. Recalls were performed every 6 months. The state of soft tissue was documented by the modified plaque and gingiva index (mPI) and sulcus bleeding index (mSBI). The restorations were evaluated for technical failures like veneering porcelain fractures, surface qualities and marginal fitting. RESULTS: Neither implant loss nor crown fractures occurred. After a mean clinical service time of 36.9 months, fractures of the veneering porcelain were registered in 1.8 % of the cases. The Kaplan-Meier survival probability regarding eventless restorations was 98.2 %. Chipping of the veneering porcelain was registered in two cemented crowns without statistical influence of the type of retention. The indices showed healthy soft periimplant tissues in both groups. CONCLUSIONS: Implant-supported zirconia crowns with a sintered veneering cap demonstrated good clinical performance. The type of retention had no influence on technical complications.

Indocyanine green videoangiography-assisted prediction of flap necrosis in the rat epigastric flap using the flow® 800 tool.

BACKGROUND: The decision to re-operate on a potentially ischemic free flap remains challenging. Indocyanine green videoangiography (ICG) with the FLOW® 800 tool is a method which allows an immediate qualitative conclusion about the patency of an anastomosis. Is it also able to predict the outcome of potentially compromised vascular free flaps? MATERIALS AND METHODS: An epigastric flap was raised and repositioned in 79 rats. Intraoperative fluorescence angiography was performed using ICG videoangiography and the FLOW® 800 tool was applied. Six regions of interest were positioned systematically over the flap, changes of the ICG fluorescence were color coded with respect to time and 474 measurements were performed. The flap was clinically monitored for one week and the resulting necrotic areas were correlated with the ICG/FLOW® 800 results. RESULTS: Mean intensity of clinically vital areas was 83.39 ± 50.96 arbitrary units (AU) and 37.33 ± 15.14 AU in necrotic areas. The receiver operating characteristic curve and Youden-Index analysis revealed that the optimal cutoff for the maximal intensity of ICG after FLOW® 800 analysis was ≤ 61.733 for the prediction of flap necrosis and > 61.733 for the prediction of flap survival (P < 0.0001; 95% CI = 0.85-0.91; Youden-Index: 0.67). The maximal intensity of ICG angiography had a specificity of 96.1% and sensitivity of 71.4%. The positive predictive value was 97.46% and the corresponding negative predictive value was 61.34%. CONCLUSION: This demonstrates the potential additional value of ICG videoangiography including FLOW® 800 analyses in the postoperative monitoring of transplanted flaps. © 2016 Wiley Periodicals, Inc. Microsurgery 37:235-242, 2017.

Form and Size Matter: Increased Risk of Thrombosis in Microvessels with Surgically Created Endothelial Lesions.

Background Atherosclerosis is a known risk factor for flap loss in microsurgery. Several microsurgical techniques, like plaque removal, have been proposed for atherosclerotic vessels, but these techniques often induce intimal injuries. The aim of this study was to investigate the impact of various endothelial defects on the risk of thrombosis in a rat acute intimal injury model. Methods Endothelial defects of various forms and sizes were created in the abdominal aorta of 30 male Wistar rats following a strict protocol. Defect sizes were measured and classified as round, horizontal, or vertical based on their configuration. An hour after reestablishing the blood flow, the abdominal aorta was harvested and the operation site was assessed for signs of thrombosis clinically and using light microscopy. Univariate and multiple linear regression analysis were performed to identify possible influencing factors on thrombosis. Results The mean defect size was 2.65 ± 1.19 mm2. Intimal lesions were classified as round in 36.7%, horizontal in 33.3%, and vertical in 30% of specimens. Thrombus formation was detected in 46.7% clinically and in 50% histologically. Univariate regression analysis revealed that defect size (p = 0.048) and vertical form (p = 0.017) were significantly associated with thrombus formation. Multiple regression analysis corroborated vertical defects as a risk factor for thrombosis (p = 0.03). Conclusion Endothelial injuries are associated with a high risk of thrombosis with highest risks associated with vertical defects. Arteries should be carefully examined for intimal defects before microvascular anastomosis, especially in the atherosclerotic patient.

Functional Outcome of CAD/CAM-Assisted versus Conventional Microvascular, Fibular Free Flap Reconstruction of the Mandible: A Retrospective Study of 30 Cases.

Background Different advantages of virtually planned and guided mandibular reconstructions have been described. Functional analyses and comparisons with conventionally reconstructed patients. Methods We retrospectively analyzed 30 cases of mandibular reconstructions that involved virtually planned or conventional microvascular, fibular free flaps that occurred between April 2011 and December 2014 at a single center. The results were also compared with a healthy cohort of 30 participants. Axiographic measurements were performed postoperatively, and uni- and multivariate regressions analyses were performed to determine the association between possible predictor variables on functional outcome. Results Operation time, hospital stay, number of osteotomies, incidence of postoperative temporomandibular joint pain, noise, and tension did not differ significantly between the conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) groups (each p > 0.05). Mouth opening and protrusion and laterotrusion also did not differ significantly (each p > 0.05) but were significantly reduced compared with the healthy group. Univariate analysis showed a significant influence of postoperative irradiation on mouth opening and laterotrusion in the conventional group (p = 0.047 and p = 0.028). In addition, multivariate analysis showed a significant influence of indication and number of osteotomies on laterotrusion (p = 0.005 and p = 0.043). Uni and multivariate analyses revealed a significant influence of indication, preoperative irradiation, and number of osteotomies on protrusion and mouth opening in the CAD/CAM group (p = 0.016, p = 0.044, and p = 0.028). Conclusion CAD/CAM-assisted reconstructions of the mandible give comparable functional results with those of the conventional technique, but no functional superiority has been established. Nevertheless, the integration of virtual planning and guided surgery is definitely of significant value but should be indicated individually case by case.

Bisphosphonate and Medication-Related Osteonecrosis of the Jaw: A Review.

For patients with malignant disease taking bisphosphonates and denosumab, the incidence of medication-related osteonecrosis of the jaw (MRONJ) is up to 15% in contrast to 0.01% in patients with osteoporosis. Clinical presentation of MRONJ extends from asymptomatic exposure of bone in 94% of patients to severe cases of mandibular fractures in a minority of 4.5%. The strongest risk factors for MRONJ are invasive dental procedures and dental infections. Advances in imaging provide more preoperation information compared with panoramic radiograph. Prevention strategies are the elimination of potential risk factors leading to invasive dental procedures and maintenance of good oral hygiene prior to the administration of antiresorptive agents. Management of MRONJ depends on the underlying disease, extent of the necrosis, and the presence of contributing therapy. Conservative therapies include topical anti-infective rinses and systemic antibiotic therapy. The most important part of surgical therapy is to remove the exposed and necrotic bone. Several options for defect closure are possible from local tissue flaps to microvascular free flap procedures. The development of MRONJ in conjunction with dental implants is a severe side effect and should be avoided if potentially harmful medication has already been administered.

Elective neck dissection in patients with head and neck adenoid cystic carcinoma: an international collaborative study.

BACKGROUND: Adenoid cystic carcinoma (ACC) accounts for 3-5 % of all head and neck malignancies. Investigations of outcomes from elective neck dissection (END) for patients with ACC are sparse. This study aimed to assess the impact of END on the survival of patients with ACC. METHODS: This retrospective multicentered study investigated 270 patients who underwent neck dissection. A multivariate analysis assessed associations of clinical and histopathologic characteristics with survival outcomes. RESULTS: The primary tumor sites included the oral cavity in 250 patients (55 %), the major salivary glands in 133 patients (29 %), the sinonasal mucosa in 68 patients (15 %), and the larynx in six patients (1 %). The overall rate of occult nodal metastases among the patients who underwent END was 17 % (38/226). The highest incidence of occult nodal metastases was with the oral cavity (66 %). The 5-year overall survival (72 and 79 % for patients with or without END, respectively) and disease-specific survival (74 and 81 % for patients with or without END, respectively) were similar in the two groups. The subgroup analysis of patients according to the primary site showed no significant impact of END on outcome. In the multivariate analysis, primary site, T classification, and N classification were the only variables associated with outcome. CONCLUSIONS: The incidence of occult neck metastases among patients with ACC is 17 %. The highest incidence of occult metastases is with the oral cavity. Statistical analysis showed no survival advantage for patients who underwent END compared with those who did not.

Trigeminal nerve injuries after mandibular oral surgery in a university outpatient setting--a retrospective analysis of 1,559 cases.

BACKGROUND: In general, trigeminal nerve injury is known as a potential risk of many surgical procedures in the oral cavity. Recent literature demonstrated that the risk of nerve injury is correlated with the experience of the surgeon. Therefore, the purpose of this study was to evaluate retrospectively the incidence of trigeminal nerve injuries in a teaching university setting. MATERIAL AND METHODS: From January 2000 to December 2009, a total of 1,559 patients underwent one intervention in the postcanine region of the mandible. Interventions included extractions, osteotomies, periradicular surgery, and implant surgery. In 2010, all 1,559 patient charts were screened. A record was made if trigeminal nerve injury was documented within the first month following surgery. These patients were re-evaluated. RESULTS: Documentation in the charts revealed that sensorial disturbance following surgery was seen in 42 patients (2.69 %). Among them, nine patients were clinically re-evaluated by the authors and 12 were interviewed by phone and observed by their dentist without any problems. Persistence of sensory disturbance was found in 5 of the 21 patients (0.32 %), and four of these five lesions were in the lingual nerve (0.25 %). Related to the type of surgery, most sensory disturbances were seen following periradicular surgery. DISCUSSION: Within the limitations of this study, it may be stated that oral surgery in an outpatient setting of a teaching university hospital resulted in very low rates of trigeminal nerve injuries. It may be concluded that adequately surveyed trainees can perform mandibular surgery without an increased risk of trigeminal sensorial disturbance.

The value of perioperative antibiotics on the success of oral free flap reconstructions.

The subject of the presented study was to monitor and compare problems and outcomes of reconstructive surgery with microvascular free flaps in the head and neck region between groups of patients treated with perioperative antibiotics and a group of patients without antibiotics. Patients requiring oral reconstructive surgery following cancer resections with microvascular free flaps were prospectively evaluated (2007-2012). Antibiotic therapy was started 30 min before the operation and administered for 10 days. Three hundred and fifty patients were included (208 male, 59.4%; 142 female, 40.6%; mean age 59.8 ± 13.2 years). 330 patients received perioperative antibiotics. Twenty patients (5.7%) who received no antibiotics for specific reasons served as the control group. Wound infections developed in 33 of 122 patients (27%) who received benzylpenicillin, 17 of 88 patients (19.3%) who received amoxicillin combined with sulbactam and 25 of 120 patients (20.8%) who received cefuroxime. Ten patients (50%) who did not receive antibiotics developed wound infections. Receiving no antibiotics or penicillin showed no benefit (P = 0.11). Those receiving cefuroxime showed significantly lower incidence of wound infections (P = 0.034; risk decreased by the factor 2.88). The use of amoxicillin combined with sulbactam showed the lowest rate of wound infections (P = 0.018; risk decreased by the factor 3.46). The use of amoxicillin combined with sulbactam appears to be the most appropriate prophylactic antibiotic followed by cefuroxime in oral microsurgical free flap reconstructions. These data may serve as a guide until a controlled multicenter prospective trial is performed comparing newer antibiotics against current standards.

Ketamine-Xylazine Anesthesia in Rats: Intraperitoneal versus Intravenous Administration Using a Microsurgical Femoral Vein Access.

BACKGROUND: Ketamine-xylazine is a frequently used combination for anesthesia in microsurgically operated rats and can be administered by intraperitoneal (IP) or intravenous (IV) injection. Both methods are associated with relatively high misadministration rates. In the present study, we want to introduce a femoral vein access that requires microsurgical cannulation but enables a 100% administration rate. METHODS: In this study, the maximal time of anesthesia was analyzed, time to response, latency time, and the total need for anesthetic agents in IP (n = 200) and IV (n = 40) anesthesia in Wistar rats for the purpose of microvascular operations. IV injections were achieved with an inserted microcatheter that was applied via a microsurgical femoral vein access. RESULTS: The time needed for the placement of the microcatheter was 5.76 ± 0.89 minutes. Maximal time of anesthesia (IP vs. IV) was 7.02 ± 1.92 versus 21.78 ± 5.77 hours (p < 0.0001), time to response was 137.5 ± 3.91 versus 18 ± 2.18 seconds (p < 0.0001), latency time 35.53 ± 3.21 versus 27.8 ± 2.88 minutes (p < 0.0001), and total volume of anesthetic 1.42 ± 0.39 versus 2.78 ± 0.73 mL (p < 0.0001), respectively. CONCLUSION: IV administration using the microsurgical femoral vein access is a feasible method with a quicker response rate and a 100% administration rate. Furthermore, it enables longer anesthesia, for example, complex microsurgical or other experimental procedures in the rat.

Are selected IL-1 polymorphisms and selected subgingival microorganisms significantly associated to periodontitis in type 2 diabetes patients? a clinical study.

BACKGROUND: We evaluated the periodontal conditions in patients with type 2 diabetes mellitus compared to metabolically healthy controls, and determined whether periodontal interleukin genotypes and microorganisms differed between participants with and without type 2 diabetes mellitus. METHODS: From April 2011 to July 2012, we prospectively enrolled healthy controls and patients with type 2 diabetes mellitus. Evaluation included assessment of medical and periodontal findings. We also recorded the presence of several interleukin gene variants and specific microorganisms, both available through commercially available diagnostic kits. Statistical significance was tested by the chi-square test and student's t-test. RESULTS: We enrolled 52 patients with type 2 diabetes mellitus and 52 healthy controls. Compared with controls, periodontal disease was significantly more severe in patients with type 2 diabetes mellitus for the following: plaque index, bleeding on probing, pocket probing depth, clinical attachment loss, severe periodontal destruction (i.e., clinical attachment loss ≥ 5 mm), and number of teeth. However, statistical analysis failed to detect significant differences with respect to the periodontal-related interleukin genotypes (p ≥ 0.58) or the selected oral microbiota (p ≥ 0.15). CONCLUSION: Based on these results, it may be assumed that chronic periodontitis in patients with type 2 diabetes mellitus is most strongly associated with inadequate oral hygiene. Periodontal interleukin genotypes and differences in oral microbiota seem to play a subordinate role.

Erosive esophageal reflux vs. non erosive esophageal reflux: oral findings in 71 patients.

BACKGROUND: The purpose of this clinical study was to assess the prevalence of acidic oral mucosal lesions and periodontal conditions in patients suffering from erosive esophageal reflux disease (ERD) compared with non erosive esophageal reflux disease (NERD) patients, both treated with long term proton pump inhibitors (PPI). METHODS: Seventy-one patients with diagnosed GERD were studied: i.e. 29 ERD and 42 NERD patients. Thorough visual examination of the oral mucosa and a periodontal evaluation was performed. The primary outcome was defined as a statistically significant difference, between the two groups, in the presence of acidic lesions of the oral mucosa and specific periodontal parameters. RESULTS: This study failed to demonstrate statistically significant differences between ERD and NERD patients with respect to the prevalence of oral mucosal lesions. However, significantly more ERD patients suffered from severe periodontitis (CAL ≥ 5 mm) as compared to NERD patients. Accordingly, it may be assumed that PPI-use had no adverse effects on the prevalence of acidic oral mucosal lesions and on periodontal destruction. CONCLUSIONS: Within the limitations of this study it may be concluded that ERD and NERD patients need separate evaluation with respect to periodontal destruction. Moreover, long term PPI medication had no adverse clinical impact on acidic oral mucosal lesions and periodontal destruction. Further studies are necessary to elucidate the role of reflux in the periodontal destruction of ERD individuals.

Incidence and outcome for patients with occult lymph node involvement in T1 and T2 oral squamous cell carcinoma: a prospective study.

BACKGROUND: The evidence base to inform the decision making process in patients with early stage oral cancer and a clinical and radiological N0 neck remains insufficient to answer the question when it is safe to "watch and wait" and when to proceed with a selective neck dissection. METHODS: A total of 327 consecutive cases of histopathologically staged T1-2, N0-1 and M0, but clinically N0, squamous cell carcinoma of the tongue were prospectively analysed. Univariate and multivariate analyses were used for statistical analysis and are represented as Kaplan-Meier analyses or Cox proportional hazard regression analysis. RESULTS: In 61 patients (18.65%) lymph node involvement was found in the histopathological processing. The mean survival of all patients was 73.3 ± 48.6 months. The 2-year and 5-year overall survival rates of all patients were 87.5% and 68.4%, respectively. The 2-year and 5-year survival rates for stage N0 were 89.1% and 70.7% compared to 83.3% and 62.9% in N1 situations. The 2-year and 5-year survival rates for stage T1 were 87.9% and 73.6% compared to 87.2% and 65.3% in stage T2, respectively. The time to recurrence in stage N0 was 35.1 ± 30.5 months compared to 25.63 ± 24.6 months in cases with N1 disease. Stage T1 was associated with a time to recurrence of 38.1 ± 33.9 months compared with 27.2 ± 22.7 months in patients classified T2.Variables found to be strongly associated with survival in the univariate analysis included older age, higher tumour and N stage, and grading. Age, tumour stage (p = 0.011, 95% CI, 1.09 to 2.0), nodal stage (p = 0.038, 95% CI, 1.02 to 2.07), and recurrence were independently and significantly associated with survival in the multivariate analysis. CONCLUSIONS: This confirms a high overall disease free survival for patients with T1 and N0 treated with single modality surgery and in common with the literature confirms the poor impact on prognosis of the N positive neck.

Diagnostic value of retrospective PET-MRI fusion in head-and-neck cancer.

BACKGROUND: To assess the diagnostic value of retrospective PET-MRI fusion and to compare the results with side-by-side analysis and single modality use of PET and of MRI alone for locoregional tumour and nodal staging of head-and-neck cancer. METHODS: Thirty-three patients with head-and-neck cancer underwent preoperative contrast-enhanced MRI and PET/CT for staging. The diagnostic data of MRI, PET, side-by-side analysis of MRI and PET images and retrospective PET-MRI fusion were systematically analysed for tumour and lymph node staging using receiver operating characteristic (ROC) analysis. The results were correlated to the histopathological evaluation. RESULTS: The overall sensitivity/specificity for tumour staging for MRI, PET, side-by-side analysis and retrospective PET-MRI fusion was 79%/66%, 82%/100%, 86%/100% and 89%/100%, respectively. The overall sensitivity/specificity for nodal staging on a patient basis for MRI, PET, side-by-side analysis and PET-MRI fusion was 94%/64%, 94%/91%, 94%/82% and 94%/82%, respectively. MRI, PET, side-by-side analysis and retrospective image fusion were associated with correct diagnosis/over-staging/under-staging of N-staging in 70.4%/18.5%/11.1%, 81.5%/7.4%/11.1%, 81.5%/11.1%/7.4% and 81.5%/11.1%/7.4%, respectively.ROC analysis showed no significant differences in tumor detection between the investigated methods. The Area Under the Curve (AUC) for MRI, PET, side-by-side analysis and retrospective PET-MRI fusion were 0.667/0.667/0.702/0.708 (p > 0.05). The most reliable technique in detection of cervical lymph node metastases was PET imaging (AUC: 0.95), followed by side-by-side analysis and retrospective image fusion technique (AUC: 0.941), which however, was not significantly better then the MRI (AUC 0.935; p > 0.05). CONCLUSIONS: We found a beneficial use of multimodal imaging, compared with MRI or PET imaging alone, particular in individual cases of recurrent tumour disease. Side-by-side analysis and retrospective image fusion analysis did not perform significantly differently.

Opened end-to-side technique for end-to-side anastomosis and analyses by an elastic true-to-scale silicone rubber model.

The end-to-side anastomosis is frequently used in microvascular free flap transfer, but detailed rheological analyses are not available. The purpose of this study was to introduce a new modified end-to-side (Opened End-to-Side, OES-) technique and compare the resulting flow pattern to a conventional technique. The new technique was based on a bi-triangulated preparation of the branching-vessel end, resulting in a "fish-mouthed" opening. We performed two different types of end-to-side anastomoses in forty pig coronary arteries and produced one elastic, true-to-scale silicone rubber model of each anastomosis. Then we installed the transparent models in a circulatory experimental setup that simulated the physiological human blood flow. Flow velocity was measured with the one-component Laser-Doppler-Anemometer system, recording flow axial and perpendicular to the model at four defined cross-sections for seven heart cycles in each model. Maximal and minimal axial velocities ranged in the conventional model between 0.269 and -0.122 m/s and in the experimental model between 0.313 and -0.153 m/s. A less disturbed flow velocity distribution was seen in the experimental model distal to the anastomosis. The OES-technique showed superior flow profiles distal to the anastomosis with minor tendencies of flow separation and represents a new alternative for end-to-side anastomosis.