3D assessment after maxillary sinus grafting with a porcine, a bovine and a synthetical bone substitute material. A randomized controlled clinical trial.

AIM: This randomized controlled clinical study focused on graft volume alterations after sinus floor augmentation with a deproteinized bovine bone mineral (DBBM, Geistlich Bio-Oss®), deproteinized porcine bone mineral (DPBM, THE GRAFT®) or a biphasic calcium phosphate (BCP, OSOPIA®). MATERIAL AND METHODS: 28 patients with edentulous situations in the posterior maxilla with less or equal to 5 mm of residual bone height received a two- staged external sinus grafting procedure with DBBM, DPBM or BCP. CBCT scans were performed prior surgery (CBCT1), directly after surgery (CBCT2) and after a healing period of 4-6 months prior implant placement (CBCT3). CBCT scans were used to analyze volumetric alterations of the sinus grafts by virtual 3D model matching of CBCT1- CBCT2 (situation after sinus grafting) and CBCT1 and CBCT2 (situation prior implant placement). RESULTS: The volume of the bone graft in the maxillary sinus (volume (VOL%) directly after grafting rated as 100%) was stable after the healing period in the DBBM (VOL%: 103±4%) and the PBBM groups (VOL%: 112± 23) with no statistically significant differences concerning 3D measurements. In the BCP group, the grafted volume declined to 66± 25% (VOL%), statistically inferior to the DBBM and DPBM groups. CONCLUSION: Concerning bone graft stability/ 25 volume DBBM and DPBM show comparable outcomes. Due to resorption, BCP showed inferior bone graft volume after healing (statistically significant) compared to DBBM and DPBM.

The impact of passive alveolar molding vs. nasoalveolar molding on cleft width and other parameters of maxillary growth in unilateral cleft lip palate.

OBJECTIVE: Passive alveolar molding (PAM) and nasoalveolar molding (NAM) are established presurgical infant orthodontic (PSIO) therapies for cleft lip palate (CLP) patients. PAM guides maxillary growth with a modified Hotz appliance, while NAM also uses extraoral taping and includes nasal stents. The effects of these techniques on alveolar arch growth have rarely been compared. MATERIAL AND METHODS: We retrospectively compared 3D-scanned maxillary models obtained before and after PSIO from infants with unilateral, non-syndromic CLP treated with PAM (n = 16) versus NAM (n = 13). Nine anatomical points were set digitally by four raters and transversal/sagittal distances and rotations of the maxilla were measured. RESULTS: Both appliances reduced the anterior cleft, but NAM percentage wise more. NAM decreased the anterior and medial transversal width compared to PAM, which led to no change. With both appliances, the posterior width increased. The alveolar arch length of the great and small segments and the sagittal length of the maxilla increased with PAM but only partially with NAM. However, NAM induced a significant greater medial rotation of the larger and smaller segment compared to PAM with respect to the lateral angle. CONCLUSIONS: NAM and PAM presented some significant differences regarding maxillary growth. While NAM reduced the anterior cleft and effectively rotated the segments medially, PAM allowed more transversal and sagittal growth. CLINICAL RELEVANCE: The results of this study should be taken into consideration when to decide whether to use PAM or NAM, since they show a different outcome within the first few months. Further studies are necessary regarding long-term differences.

Infantile human labial glands: Distribution of aquaporins and claudins in the context of paracellular and transcellular pathways.

Human labial glands consist of saliva-secreting cells which are formed by serous and predominantly mucous glandular cells. The following excretory duct system converts the isotonic saliva into a hypotonic fluid. Liquids are transported across the membrane of epithelial cells by paracellular or transcellular mode of action. We studied aquaporins (AQP) and tight junction proteins in the endpieces and duct system of human labial glands of 3-5-month-old infants for the first time. AQP1, AQP3, and AQP5 represent the transcellular transport; tight junction proteins like claudin-1, - 3, - 4, and - 7 regulate the permeability of the paracellular pathway. Specimens of 28 infants were included in this study and analyzed histologically. AQP1 was present in myoepithelial cells and in endothelial cells of small blood vessels. AQP3 showed basolateral plasmamembrane localization in glandular endpieces. AQP5 was localized at the apical cytomembrane in serous and mucous glandular cells and at the lateral membrane in serous cells. Ducts remained unstained with the antibody to AQP1, AQP3, and AQP5. Claudin-1, - 3, - 4, and - 7 were expressed mainly in the lateral plasmamembrane of serous glandular cells. In the ducts, claudin-1, - 4, and - 7 were detected at the basal cell layer, claudin-7 also at the lateral cytomembrane. Our findings provide new insights into the localization of epithelial barrier components necessary for regulating saliva-modification in infantile labial glands.

A clinical trial: Aqualizer ™ therapy and its effects on myopathies or temporomandibular dysfunctions. Part II: Subjective parameters.

OBJECTIVE: Temporomandibular dysfunction (TMD) reduces patients' quality of life (QoL). The aim was to assess the effects of initial Aqualizer™ therapy. METHODS: Group 1 (initial Aqualizer™ therapy) before definitive splint therapy or Group 2 (no initial therapy). Patients with arthrosis, partial/total prosthesis, or were undergoing splint therapy were excluded. Subjective parameters were evaluated: duration and intensity of pain, influence on wellbeing, changes in the head/neck area, handling and improvement of the Aqualizer™, improvement in QoL. The statistical significance level was 5% (p < 0.05). RESULTS: In 53 patients (Group 1 n = 25; Group 2 n = 28), the improvement in patients' well-being and intensity of pain in both groups was significant (p < 0.001). An improvement in QoL was found in 84% of patients in Group 1 and 75% in Group 2. CONCLUSION: Initial Aqualizer™ therapy can decrease the intensity of pain and increase patients'.

Recipient bed perfusion as a predictor for postoperative complications in irradiated patients with microvascular free tissue transfer of the head and neck area: a clinical analysis of 191 microvascular free flaps.

PURPOSE: Despite microvascular free tissue transfer being the mainstay of care in the reconstruction of larger maxillofacial defects, a significant number of patients experience postoperative complications due to impaired blood supply of the flap. In this context, the early influence of recipient bed perfusion remains unclear, but there is evidence that it is associated with free flap viability immediately after surgery. METHODS: We analyzed flap and recipient bed perfusion within the first 2 weeks after surgery by using the oxygen-to-see device. One hundred ninety-one patients who underwent free flap surgery in our department were included. RESULTS: Flow parameters were higher and postoperative complications were less frequent in radial forearm free flaps compared to any other type of flap. Flow parameters of the recipient bed were higher than transferred tissue at all times, implicating flap autonomization is not completed within 2 weeks. Previous radiotherapy significantly decreased flow parameters of the recipient bed but not of the flaps. Furthermore, irradiated patients with postoperative complications were found to have reduced flow parameters of their recipient bed compared to non-irradiated patients with postoperative complications. CONCLUSION: We conclude that monitoring of recipient bed perfusion is useful for detecting flap compromise of irradiated patients in the early postoperative period.

Pedicled buccal flaps as a backup procedure for intraoral reconstruction.

BACKGROUND: Intraoral soft tissue deficiency and impaired wound beds are common problems after cleft and tumour surgery or after dental trauma. Frequently, limited defects are overtreated with extensive microvascular reconstruction procedures, but pedicled flaps remain useful, as they are simple to harvest, and they provide a reliable outcome. The buccal flap, first described in the 1970s, has been used for palatine lengthening in cleft patients over decades. In the following, we present an expanded indication in cases of palatal fistula, complex vestibulum, exposed bone in orthognathic surgery, and osteoradionecrosis. METHODS: We conducted a retrospective chart review and report on all buccal flaps harvested in our department within the last 3 years with a follow-up period of at least half a year after flap surgery. Patients of all age groups and treatment indications in which a buccal flap was used were implicated in the evaluation. RESULTS: Sixteen buccal flaps were performed in 10 patients. The median age at the time of surgery was 42 years, reaching from 12 up to 66 years. Fourteen buccal flaps were used for upper jaw or palatal coverage; two buccal flaps were used in the mandible. In terms of complications (four flaps; 25%), there were two partial flap failures, one wound dehiscence and one wound dehiscence. There were no failures of the remaining mucosal flap islands after pedicle dissection. CONCLUSION: The buccal flap is a reliable and straightforward approach to challenging intraoral wound beds with soft tissue deficiency. We thoroughly discuss the additional indications for buccal flap surgery, describe the harvest technique, and provide strategies to prevent intra- and postoperative complications.

A Prospective Comparative Analysis Regarding the Assessment of Oral Mucosal Disease Using a Validated Questionnaire to Improve the Teaching of Dental Students.

Structured examination and treatment are essential in medicine. For dental students, a structured approach to the assessment of oral mucosal lesions is missing thus far. To validate an approach, a structured questionnaire was compared with the habitually used free description of oral lesions (white lesions, ulcers, hyperplasia). Thirty-three dental students were divided into two groups (Group 1 (n = 17) used the free description; Group 2 (n = 16) used a guided questionnaire) to characterize mucosal lesions in patients and make a tentative diagnosis. Although no difference was found between the groups regarding the suspected diagnosis or the histopathological findings, there was a significant advantage of the structured questionnaire in all aspects of the description compared to the free description (p = 0.000018). Thus, a structured description is an important aspect in the evaluation of oral mucosal changes, and a guided questionnaire should be implemented in the study of dentistry.

Preoperative Peroneal Artery Perforator Mapping Using Indocyanine Green Angiography: A Prospective Clinical Trial.

BACKGROUND: Perforator imaging is a prerequisite in preoperative planning of the peroneal perforator flap and the fibula skin island. Although reports indicate that indocyanine green angiography assessment method might be advantageous over conventional ultrasound-based techniques (i.e., Doppler and color duplex), in practice, clear evidence is lacking. Thus, a comparative assessment of the utility of indocyanine green angiography and ultrasound-based techniques in the identification of suitable lower leg skin perforators was performed. METHODS: A prospective clinical cohort study with a series of 12 consecutive patients was conducted to assess indocyanine green angiography, Doppler ultrasound, and color duplex ultrasound techniques for preoperative perforator detection in the lower leg before free fibula flap harvest. Anatomical dissection served as a reference. Parameters measured were perforator spatial distance to the reference (precision), operative time expenditure, and ease of device usage for assessment/outcomes. RESULTS: This study included 12 patients, with a total of 27 perforators. Exhibition of technique sensitivity and positive predictive values were as follows: indocyanine green angiography, 93 percent and 100 percent; Doppler ultrasound, 82 percent and 82 percent; and color duplex ultrasound, 89 percent and 86 percent, respectively. With regard to the indocyanine green angiography technique, the distance to the actual perforator location was significantly shorter, which aided detection and lesser time expenditure during operation. CONCLUSIONS: The indocyanine green angiography technique proved to have high precision, sensitivity, positive predictive value, and easy-to-use capabilities because of its exceptional spatial and temporal information, compared to the conventional, ultrasound-based techniques. Therefore, indocyanine green angiography is superior for preoperative perforator imaging of the lateral lower leg. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.

A Retrospective Data Analysis for the Risk Evaluation of the Development of Drug-Associated Jaw Necrosis through Dentoalveolar Interventions.

This study aimed to analyse the development of medication-related osteonecrosis of the jaw (MRONJ) in patients who underwent surgical intervention to identify potential risk factors between three different groups sorted by the type of oral surgery (single tooth extraction, multiple extraction, osteotomy). Data from patients with this medical history between 2010 and 2017 were retrospectively analysed. The following parameters were collected: sex, age, medical status, surgical intervention location of dentoalveolar intervention and form of medication. A total of 115 patients fulfilled the criteria and underwent 115 dental surgical interventions (female n = 90, male n = 25). In total, 73 (63.47%) of them had metastatic underlying diseases, and 42 (36.52%) had osteoporotic ones. MRONJ occurred in 10 patients (8.70%) (female n = 5, male n = 5). The occurrence of MRONJ was significantly correlated (p ≤ 0.05) with the mandible site and male sex. Tooth removal at the mandible site remains the main risk factor for the development of MRONJ. The risk profile of developing MRONJ after dentoalveolar interventions could be expected as follows: tooth osteotomy > multiple extractions > single tooth extraction.

A Retrospective Analysis of Postoperative Abscess Formation Following Wisdom Tooth Removal and Their Clinical Condition and Localization.

AIM: As a common procedure in oral surgery, the removal of wisdom teeth (3M) is associated with a variety of postoperative complications. This study reports of deep tissue abscesses after the removal of 3M in correlation to several factors. MATERIALS AND METHODS: Patients between 2012 and 2017 with removed 3M were retrospectively evaluated in terms of clinical condition and localization and thus assigned tog A (removal of asymptomatic 3M) or group B (removal of symptomatic 3M). Moreover, they were analyzed in terms of abscesses after the removal and correlation with various parameters: localization of the abscess, general diseases, perioperative antibiotic treatment, number of days from removal of the tooth to abscess formation, and postoperative complications after primary abscess incision. RESULTS: About 82 patients (male n = 44, female n = 38) were included, with 88 wisdom teeth removed and postoperative abscesses. Postoperative abscesses occurred more frequently in group B (n = 53) with n = 29 in IIB localization, without a significant correlation. Patients in this group were older, and there were more surgical abscess incisions needed, despite a longer treatment with oral and intravenous antibiosis that correlated with neurologic diseases and age. Younger patients reported significantly more pain. CONCLUSIONS: Detection of potential 3M pathologies at an early and asymptomatic stage is essential to avoid postoperative complications following 3M removal. Additional prospective studies are necessary to develop corresponding guidelines. CLINICAL SIGNIFICANCE: Wisdom tooth extraction is the most common operation in oral surgery, and therefore, adequate risk evaluation is still required.

An observational study of learning effects of peer-assisted learning tests in COVID-19 pandemic times.

PURPOSE: This study aimed to determine whether peer-assisted learning (PAL) is a more effective learning and test method in terms of oral- and maxillofacial surgery. MATERIAL AND METHODS: In July 2020, a total of 267 students took a PAL-based exam on fictional patients with surgical issues, in which they had to evaluate two fellow students and were themselves evaluated by two fellow students. The students evaluated their experience with the PAL-based exam through a questionnaire which consisted of five given statements (answer possibilities: agree, disagree, neutral) and two questions (answer possibilities: better, equal, worse) to rate. RESULTS: In the survey, 77.9% of the students rated PAL as a better learning method and 21% rated it as at least equally effective to the known multiple-choice (MC) test. A total of 74.9% of the students indicated that they learned more content with PAL and 20.2% said they learned the same amount; 83.7% said that their "clinical thinking has improved" through PAL. In the comments, 73% of the students noted that they think PAL is a good learning method, and at least 22% rated it as useful but in need of improvements. Only 5% did not see PAL as an acceptable learning method. In contrast to this, 1.3% saw PAL as a "bad alternative to MC tests." CONCLUSION: PAL, especially peer assessment, might represent a better learning method as it might encourage students to deal more intensively with the learning content and to improve clinical thinking.

A prospective comparative study to assess the risk of postoperative bleeding after dental surgery while on medication with direct oral anticoagulants, antiplatelet agents, or vitamin K antagonists.

BACKGROUND: The aim of this prospective study was to investigate the occurrence and severity of postoperative bleeding following dentoalveolar surgery in patients with uninterrupted anticoagulation therapy (AT). METHODS: Patients receiving AT (vitamin k antagonist (VK), direct oral anticoagulants (DOAC) or antiplatelet therapy (APT) and in need of surgical intervention classified as A, B or C (single or serial tooth extraction, osteotomy, or implant placement) were studied between 2019 and 2021. A healthy, non-anticoagulated cohort (CG) served as a control group. The main outcomes measured were the frequency of postoperative bleeding, the classification of the severity of postoperative bleeding (1a, 1b, 1c, 2, 3), and the correlation with the AT surgical intervention classification. RESULTS: In total, 195 patients were included in the study, with 95 patients in the AT group and 100 in the CG. Postoperative bleeding was significant in the AT group vs. the CG (p = 0.000), with a significant correlation with surgical intervention class C (p = 0.013) and the severity class of bleeding 1a (p = 0.044). There was no significant correlation with procedures of type A, B or C for the other postoperative bleeding gradations (1b, 1c, 2 and 3). There was a statistically significant difference in the occurrence of postoperative bleeding events between the DOAC/APT group and the VK group (p = 0.036), but there were no significant differences regarding the other AT agents. CONCLUSION: The continuation of anticoagulation therapy for surgical interventions also seems reasonable for high-risk interventions. Although significantly more postoperative bleeding occurs, the severity of bleeding is low. The perioperative management of anticoagulated patients requires well-coordinated interdisciplinary teamwork and detailed instruction of patients. Clinical trial registration The study is registered (29.03.2021) at the German clinical trial registry (DRKS00024889).

Thermal Imaging in a Clinically Non-assessable Free Flap Reconstruction of the Face.

Free flap monitoring and early detection of malperfusion are a central aspect in reconstructive surgery. Warm ischemia, measured as the time a certain tissue is able to survive without any additional medical or thermal treatment, ranges from hours in muscle and nerval tissue up to days in bony tissue. Hence, meticulous flap monitoring is essential to discover early signs of malperfusion and decide upon timely re-intervention. Besides clinical examination techniques and Doppler sonography, a multitude of mostly experimental procedures are available to evaluate free flap perfusion. Particularly in older patients, the assessment of the skin island in microvascular grafts is a demanding task because the natural loss of elasticity, the reduction of subcutaneous tissue, and the decrease in water content limit the visibility of capillary filling and favor hematomas. We report a case of a 90-year-old woman with an extensive cutaneous squamous cell carcinoma of the right zygomatic and lateral orbital region without any locoregional or distant metastasis. Due to the resilient health status, we decided for a surgical approach with consecutive microvascular radial forearm flap reconstruction. On account of the difficult assessment of elderly skin after microvascular transplantation, we decided on additional flap monitoring by thermal heat imaging during the operation and aftercare. This case report discusses the successful application of thermal heat imaging in a clinical non-assessable free flap and discusses the application of dynamic infrared thermography as a monitoring tool in microvascular free flap surgery.

Kobra Surgery Simulator-A Possibility to Improve Digital Teaching? A Case-Control Study.

Computer-aided simulations have long been of great importance in university teaching; however, to date, there is limited use of such simulations in the dental surgical sector. For this purpose, an oral surgery simulator, "Kobra", was implemented in student training and was evaluated for dental education. Dental students (group 1, third-year and group 2, fourth-year) and dentists of the faculty (control group) were trained to use the simulator. The outcomes for group 1 (apicoectomy of an upper lateral incisor with Kobra), group 2 (removal of an impacted lower wisdom tooth with Kobra) and the control group (both procedures with Kobra) were evaluated. For evaluation purposes, subjective parameters (improvement of practical skills, comparison between conventional training and Kobra simulation, and implementation of simulation-based teaching) and objective parameters (removal of bone, tooth substance and soft tissue measured while performing the Kobra simulation) were assessed using questionnaires with a scale ranging from 1-5. A total of 49 students (third-year n = 29, with 22 women and 7 men; fourth-year n = 20, with 17 women and 3 men) and 10 dentists (women n = 5 and men n = 5) participated. Compared to the Kobra simulation, the conventional training method with plastic models was still favored (the difference was non-significant). Compared to the dentists, the simulation data showed a less precise surgical performance of the students (the difference was not significant). The Kobra simulation may offer an additional method to conventional surgery training using plastic models, with benefits for students and faculty staff.

Management of anticoagulated patients in dentoalveolar surgery: a retrospective study comparing bridging with heparin versus unpaused vitamin K antagonist medication.

BACKGROUND: The aim of this study was to investigate the occurrence of postoperative bleeding following dentoalveolar surgery in patients with either continued vitamin K antagonist medication or perioperative bridging using heparin. METHODS: A retrospective study was performed analyzing patients who underwent tooth extraction between 2012 and 2017. Patients were retrospectively allocated into two comparative groups: un-paused vitamin K antagonist medication versus bridging using heparin. A healthy, non-anticoagulated cohort with equivalent surgery served as a control group. Main outcome measures were: the occurrence and frequency of postoperative bleeding, the number of removed teeth, the surgical technique of tooth removal (extraction/osteotomy/combined extraction and osteotomy) and the prothrombin time. RESULTS: In total, 475 patients were included in the study with 170 patients in the group of un-paused vitamin K antagonist medication VG, 135 patients in the Bridging group BG and 170 patients in the control group CG. Postoperative bleeding was significant: CG versus VG p = 0.004; CG versus BG p < 0.001, BG versus VG p < 0.001. A significant correlation of number of the extracted teeth in the BG (p = 0.014) and no significance in VG (p = 0.298) and CG (p = 0.210) and in the BG versus VG and CG with p < 0.001 in terms of surgical intervention extraction. No difference observed in terms of prothrombin time. CONCLUSIONS: Bridging with heparin increases the risk for bleeding compared to un-paused vitamin K antagonist medication. The perioperative management of anticoagulated patients requires a well-coordinated interdisciplinary teamwork to minimize or at best avoid both: postoperative bleeding and thromboembolic incidences.

A clinical trial: Aqualizer ™ therapy and its effects on myopathies or temporomandibular dysfunctions. Part I: Objective parameters.

OBJECTIVE: Symptoms of temporomandibular dysfunction (TMD) may include pain in the muscles or restrictions opening the mouth. The aim of this study was to assess the effects of initial Aqualizer™ therapy. METHODS: Group 1 received initial Aqualizer™ therapy before definitive hard splint; Group 2 received no initial therapy. Patients with arthrosis, partial/total prosthesis or undergoing splint therapy were excluded. Objective (temporomandibular joint palpation, temporomandibular joint auscultation, palpation of the chewing muscles, and mobility of the lower jaw) parameters were evaluated. The level of statistical significance was 5% (p < 0.05). RESULTS: In 53 patients (Group 1 n = 25; Group 2 n = 28), a significant improvement (p < 0.001) was found in Group 1 in pain on palpation (masseter muscle, temporal muscle, post-mandibular region, lateral pterygoid muscle, and suboccipital region), but no significant differences in jaw mobility were found. CONCLUSION: Aqualizer™ therapy produces significant improvement of primary symptoms.

Oxidative and Nitrosative Stress in Oral Squamous Cell Carcinoma.

INTRODUCTION: The incidence of oral squamous cell carcinoma (OSCC) shows a constant increase, while the long-term outcome remains poor over the last decades. Radical oxygen and nitrogen species (RONS) - initially released by carcinogens, such as alcohol and tobacco, and later maintained by the tumor microenvironment - appear to be strongly associated to chronic inflammation, tumor induction, progression, and metastatic spread. The aim of this study was to evaluate the role of oxidative and nitrosative stress in primary OSCC compared to healthy tissue specimens and to identify their impact on tumor carcinogenesis. MATERIALS AND METHODS: In this basic research study, tissue samples of 30 patients with primary OSCC were evaluated for the expression of pAKT, pERK, 3-NT, NOS1, NOS3, MAPK1, and IP-8 by immunohistochemistry and RT-PCR and compared to those of a healthy control group (n = 30). RESULTS: The results showed a significantly increased expression of pAKT (p < 0.001), pERK (p = 0.01), 3-NT (p = 0.039), NOS1 (p = 0.025), NOS3 (p = 0.046), and MAPK1 (p = 0.032) in OSCC tissue samples compared to healthy controls. CONCLUSION: The results of this study prove the tested stable degradation products to be suitable for the detection of RONS in OSCC. Moreover, the significantly increased expression underlines the role of RONS in carcinogenesis of OSCC, suggests specific mechanisms of detection, and anticipates supplementary research.

Diversity of mucins in labial glands of infants.

Mucins as highly glycosylated proteins comprise multiple functions like protection, homeostasis, immune defense, cell signaling. Various epithelial tissues including glandular structures express different specific mucin types. We investigated labial salivary glands in infants for the occurrence of MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, and MUC7 by immunohistochemistry. MUC1 and MUC4 were detected in serous and ductal glandular cells, partially intensified at the apical plasma membrane. MUC3 was found in ductal glandular cells and in myoepithelial cells. MUC5B exhibited a mosaic expression pattern in mucous glandular endpieces. MUC2 and MUC7 were abundant in serous acini. Glandular structures were negative for MUC5AC. A comprehensive study of specific mucins in labial salivary glands of infants was presented for the first time. As a representative of the minor salivary glands, labial glands are, due to their localization, directly exposed to environmental influences. The distribution of a broad spectrum of mucins in infantile labial glands indicates their importance early in human development to sustain oral health.

Evaluation of neck dissection with frozen section biopsy - Management of levels IV and V.

INTRODUCTION: Neck dissection is an essential component of oral cancer therapy. Based on a standardised approach to cervical lymph node management, we seek to define the relevance of neck dissection extension in cN + cases. MATERIAL AND METHODS: A retrospective analysis from January 2009 to February 2017 identified 84 patients with oral squamous cell carcinoma with a cN + neck or histologically proven lymph node involvement in intraoperative frozen sectioning and who received modified radical neck dissection according to the presented neck dissection algorithm. RESULTS: Overall 11 patients showed lymph node metastasis level IV or V, whereas 19 developed disease recurrence, of which 5 cases were neck recurrences. A total of 30 patients died within the time of observance (overall survival of n = 54). None of those patients with pN + status in levels IV and V reached a 5-year survival. DISCUSSION: With a look to the possibility of a 5-year survival in patients with a N+ status in level IV and V, the justification for a radical approach to the neck appears questionable. However, modified radical neck dissection appears to be a suitable for a high-risk oral cancer subgroup. A randomised controlled trial is needed to define guidelines for the neck dissection extent in c/pN + cases.

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.