Congenital Unilateral Zygomatico-Maxillo-Mandibular Fusion.

Congenital fusion of the jaws (syngnathia) is a rare and severe disorder. The authors report a case of bony fusion of the left mandible with the maxilla and zygomatic complex in a 5-day-old male who was not able to feed and open his mouth normally. Early surgery was performed to release the bony fusion on the tenth day of life. The authors present a new technique based on the intraoperative use of 3-dimensional surgical guides.

Immune cell infiltration in head and neck squamous cell carcinoma and patient outcome: a retrospective study.

BACKGROUND: Human papillomavirus (HPV) prevalence in oropharynx squamous cell carcinoma (OPSCC) is on the rise. HPV-linked OPSCCs represent a distinct clinical entity with a better treatment response and patient survival compared to tumors not linked to HPV. An emerging role in treatment response has been attributed to immune cell infiltration in human tumors. In this study, we investigated immune cell infiltration in human SCC of the head and neck region and its relation to overall survival after treatment with surgery (with or without radiotherapy) or concomitant chemo (or cetuximab)-radiotherapy. MATERIALS AND METHODS: Paraffin-embedded tumor samples of 136 patients with SCC of the larynx, hypopharynx, oral cavity and oropharynx were processed for immunohistochemical detection of CD3+ T-cells, CD8+ cytotoxic T-cells, CD20+ B-cells and CD163+ M2 macrophages within the tumor infiltrated area. Clinico-pathological data were analyzed as a function of tumor location and p16-status. Immune cell infiltration was represented as stained area on the whole tumor infiltrated area, compared for the different tumor locations and correlated to patient survival. RESULTS: Patients with oropharynx tumors expressing significant p16 levels (p16-sg) had a 5-year overall survival of 85% compared to 43% for patients with no significant p16 (p16-ns) expression (HR: 0.3 - 95% CI: 0.1-0.6). Median immune cell infiltration (T- and B-lymphocytes) was significantly elevated in p16-sg oropharyngeal tumors, compared to p16-ns oropharyngeal tumors and to all other head and neck tumor locations. No difference in CD163+ macrophage infiltration was observed across the different patient groups. In the whole population, a high infiltration by CD3+ T-lymphocytes was associated to a significantly (p = .03; HR: 0.6, 95% CI: 0.4-0.97) better overall survival. CONCLUSION: Oropharynx cancer with significant p16 expression showed an increased overall survival and elevated T- and B-lymphocyte infiltration, which suggests a prognostic relevance of immune cell infiltration.

Microradiographic and histological evaluation of the bone-screw and bone-plate interface of orthodontic miniplates in patients.

OBJECTIVES: To describe the tissue reactions at the bone-titanium interface of orthodontic miniplates in humans. MATERIALS AND METHODS: Forty-two samples, consisting of tissue fragments attached or not to miniplates or their fixation screws, were collected from 24 orthodontic patients treated with miniplate anchorage, at the time of removal of their miniplates. The samples were embedded in methylmethacrylate and cut into undecalcified sections which were submitted to microradiographic analysis. The sections were also stained and examined under ordinary light. RESULTS: Three types of reactions were observed both on the histological sections and on the microradiographs. 1. The majority of the stable miniplates were easy to remove (34/42). The tissue samples collected consisted mainly in mature lamellar bone with some medullary spaces containing blood vessels, 2. two screws were highly osseointegrated and required the surgeon to remove them by trephining (2/42). They were surrounded by bone tissue which extended to the miniplate. The histological features were similar to the previous group, though the bone-screw contact was higher, and 3. in six samples obtained after unstable miniplate removal during the treatment, we observed either some woven bone trabeculae or loose connective tissue, without any histological sign of inflammation. LIMITATIONS AND CONCLUSION: For evident ethical reasons, our data were limited by the size of the tissue fragments and the limited number of patients and variety of clinical presentations. The healing reactions consisted mainly in mature lamellar bone tissue sparsely in contact with the screw or the miniplate, with signs of a moderate remodelling activity.

Study of the PD-L1 expression, T-cells density and immunoscore in paired baseline tumor biopsies and surgical specimens in squamous cell carcinoma of the oral cavity.

OBJECTIVES: Primary objective was to evaluate the correlation between immune marker expression in baseline tumor biopsies and their respective surgical specimens in squamous cell carcinoma of the oral cavity (OCSCC). Secondary objective was to assess the impact of these markers on overall (OS) and disease-free survival (DFS). MATERIALS AND METHODS: Patients with a histological diagnosis of oral squamous cell carcinoma treated surgically between 2012 and 2020 were included in this retrospective, translational monocentric study. The expression of PD-L1, T-cells markers and an OCSCC-adapted immunoscore were evaluated by multiplex immunohistochemistry. RESULTS: One hundred and four patients (mean: 58 years) were included. Seventy patients had paired samples available. Poor correlation was highlighted for PD-L1-positive surface expression (r = 0.29) and combined positive score (CPS). For CPS ≥ 20 and CPS ≥ 1, correlation coefficient r was 0.24 and 0.46 respectively. T-cells density showed also poor correlation with a r of 0.57 and 0.31 for CD3 and CD8 T-cells, respectively. Univariate survival analyses showed significant better OS and DFS (P < 0.05) for patients with stage III-IV OCSCC with a high compared to a low immunoscore, based on surgical samples only. CONCLUSION: Our study showed poor correlation in PD-L1 expression, CPS, T-cells density and immunoscore between baseline tumor biopsies and surgical resection specimens. In addition, the immunoscore may emerge as a potential prognostic factor in advanced squamous cell carcinoma of the oral cavity. If surgical specimens are available, they may be of interest for clinical practice decision.

Comparative pharmacokinetics, biodistribution, metabolism and hypoxia-dependent uptake of [18F]-EF3 and [18F]-MISO in rodent tumor models.

BACKGROUND AND PURPOSE: [18F]-EF3 allows non-invasive detection of hypoxia. In the framework of its validation, we aimed at comparing its pharmacokinetics, biodistribution, metabolism and specificity for hypoxia with the hypoxia tracer [18F]-FMISO. MATERIALS AND METHODS: C3H mice were injected IV with 3.7-18.5 MBq of one of the two tracers. For pharmacokinetics experiments, blood, urines and feces were collected. For biodistribution experiments, 13 different organs were harvested. To assess the hypoxia-specificity of the tracers, intramuscular syngeneic FSA II tumor bearing mice breathing air or carbogen were used. Animals were sacrificed from 5 to 440 min after injection. Radioactivity was assessed ex-vivo in a gamma counter. Tracer metabolites were assessed with radio-HPLC of acetonitrile soluble fractions of tissues. RESULTS: Elimination half-life in blood (mono-exponential fit) reached 81.8 and 99.7 min for [18F]-EF3 and [18F]-MISO, respectively (NS). After 440 min, 71+/-7% (mean+/-SD) of injected activity of [18F]-EF3 was collected in the urine while 9+/-2% was collected in the feces, compared to 71+/-15% and 23+/-15% for [18F]-MISO (NS). Biodistribution was similar with a homogeneous distribution in most organs as early as 5 min after injection. With time, an increased activity in organs involved in excretion (kidney, bladder, liver and GI tract) was measured for both tracers; however, an increased background activity in "oxic" normal tissues (brain, lung, and esophagus) was also observed for [18F]-MISO. The percentage of metabolites was higher for [18F]-MISO compared to [18F]-EF3 in nearly all samples. Tumor-to-muscle ratios (TMRs) ranging from 2 to 4 were obtained under air-breathing condition for both tracers. CONCLUSION: Both tracers exhibited a similar pharmacokinetics and biodistribution in mice and accumulated in an hypoxia-dependent manner in tumors. However, more aspecific activity was observed with [18F]-MISO at late time points after tracer injection in normal tissues.

Modified miniplates for temporary skeletal anchorage in orthodontics: placement and removal surgeries.

PURPOSE: Skeletal anchorage systems are increasingly used in orthodontics. This article describes the techniques of placement and removal of modified surgical miniplates used for temporary orthodontic anchorage and reports surgeons' perceptions of their use. PATIENTS AND METHODS: We enrolled 97 consecutive orthodontic patients having miniplates placed as an adjunct to treatment. A total of 200 miniplates were placed by 9 oral surgeons. Patients and surgeons completed questionnaires after placement and removal surgeries. RESULTS: Fifteen miniplates needed to be removed prematurely. Antibiotics and anti-inflammatories were generally prescribed after placement but not after removal surgery. Most surgeries were performed with the patient under local anesthesia. Placement surgery lasted on average between 15 and 30 minutes per plate and was considered by the surgeons to be very easy to moderately easy. The surgery to remove the miniplates was considered easier and took less time. The patients' chief complaint was swelling, lasting on average 5.3 +/- 2.8 days after placement and 4.5 +/- 2.6 days after removal. CONCLUSIONS: Although miniplate placement/removal surgery requires the elevation of a flap, this was considered an easy and relatively short surgical procedure that can typically be performed with the patient under local anesthesia without complications, and it may be considered a safe and effective adjunct for orthodontic treatment.

Validation of a windowing protocol for accurate in vivo tooth segmentation using i-CAT cone beam computed tomography.

BACKGROUND: Validation of three-dimensional (3D) reconstructions of full dental arches with crowns and roots based on cone beam computed tomography (CBCT) imaging represents a key issue in 3D digital dentistry. OBJECTIVES: The aim of the study was to search for the most accurate in vivo windowing-based manual tooth segmentation using CBCT. The null hypothesis was that all applied windowing protocols were equivalent in terms of in vivo tooth volume measurement using CBCT. MATERIAL AND METHODS: This retrospective study was based on preoperative CBCT images from patients who underwent further tooth extractions for reasons independent of this study. Written informed consent was obtained from all the participants, and the study was approved by the Ethics Committee of Cliniques Universitaires Saint Luc (Brussels, Belgium). The radiological protocol was I-CAT CBCT, 0.3 mm slice thickness, 8 cm × 16 cm field of view, 120 kVp, and 18 mAs. A total of 36 teeth were extracted from 14 patients between the ages of 18 and 68 years. Using 3D Slicer software, segmentations were performed twice by 2 independent observers, with a 1-month time period between the 2 segmentations to study intraand inter-observer repeatability and reproducibility. Four windowing protocols (level/window) were applied: 1. 1131/1858, 2. 2224/4095, 3. 1131/4095, and 4. AUTO, an automatic protocol provided by default by the software. A total of 576 segmentations were performed. Tooth volumes were automatically calculated using the software. To compare the volumes obtained from CBCT segmentations with a gold-standard method, we laser-scanned the extracted teeth. RESULTS: Excellent intraand inter-observer intraclass correlations were found for all of the protocols used. The best windowing protocol was 1131/1858 for both observers. Tooth volumes were obtained by manual segmentation of the CBCT images and using windowing protocol 1131/1858. No significantly different tooth volumes were found by laser scanning. CONCLUSIONS: Our null hypothesis was rejected. Only windowing protocol 1131/1858 allowed for significantly closer 3D in vivo segmentation of a tooth compared to I-CAT CBCT, with excellent intra-observer repeatability and inter-observer reproducibility.

Closure of radial forearm free flap donor site defect with a local meshed full-thickness skin graft: a retrospective study of an original technique.

INTRODUCTION: Closure of the radial free flap donor site remains a problem. Donor site morbidity is related to poor skin graft taking, inaesthetic appearance and hand sensory dysfunction. PATIENTS AND METHODS: From January 1998 to December 2002, 41 radial free flaps were harvested. The donor site closure technique consisted of a combination of: flexor tendons coverage, purse string and local meshed full-thickness skin graft. RESULTS: The mean time of wound healing of the donor site was 4.68 weeks. Four patients (16%) developed a partial necrosis of the skin graft. Nine patients (36%) showed a definitive hypoaesthesia in the dorsal region of the thumb. Neither total necrosis of the skin graft nor exposure of flexor carpi radialis tendon was noted. The average visual analogue scale of the aesthetics was 6 (patients), 4.18 (students) and 7.2 (first author) out of 10. CONCLUSION: This technique for closing a small-to-medium sized radial donor site defect is recommended.

Microsatellite alterations in head and neck squamous cell carcinoma and relation to expression of pimonidazole, CA IX and GLUT-1.

BACKGROUND AND PURPOSE: Because the locoregional control for HNSCC is still disappointing, research efforts focus on the exploration of new molecular markers located in both tumour and microenvironment, which could help stratify patients. The aim of the present work was therefore first to assess microsatellite alterations and hypoxia in HNSCC as possible molecular markers. Second, a relation between both was investigated, as hypoxia is known to select for genetic alterations. MATERIAL AND METHODS: Forty-eight patients with advanced HNSCC treated by surgery+/-radiotherapy were included. MSI and LOH were investigated with microsatellite markers using automatic fragment analysis. The presence of hypoxia was assessed by immunohistochemistry for pimonidazole, CA IX and GLUT-1. The mutual relationship between MSI/LOH and hypoxia was evaluated. RESULTS: No MSI was detected in this patient group. LOH occurred mostly on chromosomal arms 3p, 5q, 9p, 17p and 17q. Patients with LOH at D17S799, located in the near environment of p53, showed a higher CA IX expression (p=0.01). CONCLUSIONS: LOH is a possible molecular marker in HNSCC. The positive correlation between LOH at D17S799 and CA IX is in full concordance with previous publications linking hypoxia to selective pressure on the p53 gene.

Relative biologic effectiveness determination in mouse intestine for scanning proton beam at Paul Scherrer Institute, Switzerland. Influence of motion.

PURPOSE: To determine the relative biologic effectiveness (RBE) of the Paul Scherrer Institute (PSI) scanning proton beam in reference conditions and to evaluate the influence of intestine motion on the proton dose homogeneity. METHODS AND MATERIALS: First, RBE was determined for crypt regeneration in mice after irradiation in a single fraction. Irradiation was performed at the middle of a 7-cm spread out Bragg peak (SOBP; reference position), as well as in the proximal part of the plateau and at the distal end of the SOBP. Control gamma-irradiation was randomized with proton irradiation and performed simultaneously. Second, motion of mouse intestine was determined by radiographs after copper wire markers had been placed on the jejunum and intestinal wall. RESULTS: Proton RBE (reference (60)Co gamma) was equal to 1.16 for irradiation at the middle of the SOBP and to 1.11 and 1.21 for irradiation in the initial plateau and end of the SOBP, respectively. The confidence intervals for these RBE values were much larger than those obtained in the other proton beams we have tested so far. They exceeded +/-0.20 (compared with the usual value of +/-0.07), which resulted from the unusually large dispersion of the individual proton data. The instantaneous positions of the mice intestines varied by +/-2 mm in the course of irradiation. CONCLUSION: The results of this study have shown that the RBE of the PSI proton beam is in total accordance with the RBE obtained at the other centers. This experiment has corroborated that proton RBE at the middle of the SOBP is slightly larger than the generic value of 1.10 and that there is a slight tendency for the RBE to increase close to the end of the SOBP. Also, excessive dispersion of individual proton data may be considered to result from intestine motion, taking into account that irradiation at the PSI is delivered dynamically by scanning the target volume with a pencil proton beam ("spot scanning"). Because 2-mm movements resulted in significant variations in local dose depositions, this should be considered for moving targets. Strategies to reduce this effect for the spot scanning technique have been developed at the PSI for radiotherapy of humans.

In vivo colocalization of 2-nitroimidazole EF5 fluorescence intensity and electron paramagnetic resonance oximetry in mouse tumors.

BACKGROUND AND PURPOSE: The primary objective of this study was to establish in vivo the relationship between 2-2-nitro-1H-imidazol-1yl-N-(2,2,3,3,3-pentafluoropropyl)-acetamide (EF5) adduct formation and intratumoral oxygen concentrations measured by electron paramagnetic resonance (EPR) in a tumor model mimicking a clinical situation. The secondary objective was an attempt to calibrate in situ the immunofluorescence (IF) signal with EPR oximetry. MATERIALS AND METHODS: IM syngeneic fibrosarcoma (NFSA) bearing C3H mice were used. Three days after injection of a paramagnetic charcoal into the tumor, the mice were anesthetized, injected with the hypoxic marker EF5, and monitored every 20 min for 3 h with a low-frequency EPR spectrometer. Animals were allowed to breath either under 21 or 100% O(2). Tumors were then harvested, frozen, cut into sections including the charcoal and processed for EF5 adducts detection using monoclonal antibodies. Slices were viewed with a fluorescence microscope and 190x140 micrometer areas surrounding the charcoal were digitized and analyzed with the NIH-Image and Adobe Photoshop software. The fluorescence intensity (FI) was measured in the whole pictures and in strips of 10 micrometer around the charcoal. RESULTS: EF5 binding increased with decreasing pO(2), most substantially at pO(2) below 5 mm Hg. Baseline (ambient air) pO(2) reached 3.2+/-2.1 mm Hg in NFSA tumors. It increased to 9.8+/-3.2 mm Hg under 100% O(2). A statistically significant correlation was observed on an individual tumor basis between the FI in the first 10 micrometer strip around the charcoal and the pO(2) determined by EPR oximetry (Wilcoxon signed rank test: P<0.001). CONCLUSIONS: The present study confirms the intrinsic relationship between EF5 adduct binding and intratumoral pO(2) in an in vivo environment under biologically-relevant pO(2) values of less than 10 mm Hg.

Design of a cylindrical brachytherapy implant applicator for the irradiation of an intestinal segment in mice.

YingExperimental determination of the RBE of new isotopes for brachytherapy implants (e.g. iodine-125 and palladium-103) remains a very difficult problem, especially in small animals, where the seeds cannot be implanted easily in the planned geometry in a reproducible way. This technical note describes an original device that makes it possible to irradiate a segment of the intestine in mice for the purpose of determining the RBE for crypt regeneration. The device is a length of tube (3.4 mm and 7 mm internal and external diameter, respectively) whose external surface has been longitudinally grooved and into which the seeds can be squeezed (each groove holds either one or two seeds). The tube is composed of two sections. This seed container can be surgically positioned around an intestinal ansa while the mice are anesthetized. The mean dose rates in the intestine (for eight seeds) were found to be 86.3 +/- 5.9 and 79.0 +/- 5.4 cGy/h for 29.2 MBq (1 U) iodine and 28.6 MBq (1 U) palladium seeds, respectively. So far, more than 100 mice have been irradiated successfully. Full dose-effect relationships can be obtained using the same seeds and applying them successively in different groups of animals (which ensured the accuracy of the relative doses).

Determination of tumour hypoxia with the PET tracer [18F]EF3: improvement of the tumour-to-background ratio in a mouse tumour model.

PURPOSE: The 2-(2-nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)acetamide (EF3) is a 2-nitroimidazole derivative which undergoes bioreductive activation under hypoxic conditions. Using the PET tracer [18F]EF3 in mice, tumour-to-muscle ratios ranging from 1.3 to 3.5 were observed. This study investigated the impact of various interventions aimed at increasing [18F]EF3 elimination, thus potentially increasing the tumour-to-noise ratio in mice, by increasing the renal filtration rate (spironolactone, furosemide), decreasing tubular re-absorption (metronidazole, ornidazole, amino acid solution) or stimulating gastro-intestinal elimination (phenobarbital). METHODS: C3H mice were injected i.v. with an average of 12.95 MBq of [18F]EF3. Drugs were injected i.v. 15 min before the tracer or daily 4 days prior to the experiment (phenobarbital). Anaesthetised mice were imaged from 30 to 300 min with a dedicated animal PET (Mosaic, Philips). Regions of interest were delineated around the tumour, bladder, heart, liver and leg muscle. Radioactivity was expressed as a percentage of injected activity per gram of tissue. RESULTS: Ornidazole decreased the urinary excretion and increased the liver uptake of [18F]EF3, but without causing any changes in the other organs. Phenobarbital significantly increased the liver concentration and decreased radioactivity in blood and muscle without affecting the tracer uptake in tumour. Consequently, a small but non-significant increase in tumour-to-noise ratio was observed. Although some effects were observed with other drugs, they did not modify the tumour-to-noise ratio. CONCLUSION: Only phenobarbital induced a trend toward an increased tumour-to-noise ratio that could possibly be tested in the clinical situation.

Accessory or sublingual salivary gland biopsy to assess systemic disease: a comparative retrospective study.

Minor salivary gland biopsies are commonly performed as part of the diagnosis of Sjögren's syndrome or other systemic diseases. Until now, a lip biopsy taken from inside the inferior lip has been the most often performed method to assess the accessory salivary glands. Because of the risk of damaging the inferior alveolar nerve and of harvesting non-contributive biopsies, for the past several years we have chosen the sublingual biopsy described by Adam. The aim of this study was to describe the indication and diagnosis and to evaluate work incapacity, pain and the complication rate among our salivary gland biopsies. In this retrospective study, we evaluated 79 biopsies (lip, n=24, and sublingual, n=55) taken at the Department of Oral and Maxillofacial Surgery of the University Hospital St-Luc, Brussels, by multiple junior trainees and senior surgeons (n=17). Data were collected from record study and from telephonic patient questionnaires. The three major indications were: sicca syndrome (24%), suspicion of Sjögren's syndrome (32%) or exclusion of other systemic diseases (44%). The histology results of the lip and sublingual biopsies, respectively, were: normal tissue (29%, 24%), chronic inflammation (29%, 41%), compatible, but not characteristic for Sjögren (8%, 7%), Sjögren's syndrome (13%, 24%), salivary gland atrophy (13%, 0%) or non-contributive (8%, 0%). The procedures were both almost painless (time during which painkillers had to be taken: 0.33 vs. 0.69 days, NS) and work incapacity was not encountered in any group. After one lip biopsy we had to deal with a permanent anesthesia of the lower lip (6.6%), and after one sublingual biopsy a swelling of the floor of the mouth had to be incised under local anesthesia (2.7%). Thus, sublingual biopsy is an easy procedure with low morbidity and excellent reliability in comparison to lip biopsy. No salivary gland atrophy and no non-contributive biopsies were encountered; no important bleeding or nerve lesion was recorded after sublingual biopsies.