Stability of maxillary expansion osteotomy using patient-specific fixation implants without necessitating removable appliances: a retrospective analysis.

OBJECTIVE: This study aimed to evaluate the long-term stability of surgical maxillary expansion using patient-specific fixation implants (PSFIs) without intraoral retention. MATERIALS AND METHODS: Fifteen patients who had undergone segmented Le Fort I osteotomy and PSFIs with available preoperative (t0) early (t1) and 1-year follow-up computed tomography (CT) scans (t2) were evaluated. The early and 1-year 3D models were superimposed to transfer the bony landmarks; the distances between each pair of landmarks at the different time points were then measured. The distances between the canines and second molars were also measured directly on the CT scans. RESULTS: The achieved maxillary expansions ranged from a median of 4.39 (2.00-6.27) mm at the greater palatine foramina to a median of 2.14 (1.56-2 > 83) mm at the canine level of the palatal bone. One year postoperatively, the changes in skeletal diameters ranged from a median of - 0.53 (- 1.65 to 0.41) mm at the greater palatine foramina (p = 0.12) to 0.17 (- 0.09 to 0.32) mm at the canine level of the palatal bone (p = 0.56). Changes in dental arch diameters ranged from a median of - 0.6 (- 2 to 0.00) mm between the second molars to - 1.3 (- 1.8 to - 0.25) mm between the canines (P < 0.05). CONCLUSION: This study showed the stability of maxillary expansion osteotomy using PSFIs, even without postoperative intraoral retention. CLINICAL RELEVANCE: PSFIs are a reliable method for the surgical treatment of transverse maxillary discrepancy. PFSIs are easy-to-use and improve surgical accuracy.

Evaluation of Proton MR Spectroscopy for the Study of the Tongue Tissue in Healthy Subjects and Patients With Tongue Squamous Cell Carcinoma: Preliminary Findings.

Purpose: To noninvasively assess spectroscopic and metabolic profiles of healthy tongue tissue and in an exploratory objective in nontreated and treated patients with tongue squamous cell carcinoma (SCC). Methods: Fourteen healthy subjects (HSs), one patient with nontreated tongue SCC (NT-SCC), and two patients with treated tongue SCC (T-SCC) underwent MRI and single-voxel proton magnetic resonance spectroscopy (1H-MRS) evaluations (3 and 1.5T). Multi-echo-times 1H-MRS was performed at the medial superior part (MSP) and the anterior inferior part (AIP) of the tongue in HS, while 1H-MRS voxel was placed at the most aggressive part of the tumor for patients with tongue SCC. 1H-MRS data analysis yielded spectroscopic metabolite ratios quantified to total creatine. Results: In HS, compared to MSP and AIP, 1H-MRS spectra revealed higher levels of creatine, a more prominent and well-identified trimethylamine-choline (TMA-Cho) peak. However, larger prominent lipid peaks were better differentiated in the tongue MSP. Compared to HS, patients with NT-SCC exhibited very high levels of lipids and relatively higher values of TMA-Cho peak. Interestingly, patients with T-SCC showed almost nonproliferation activity. However, high lipids levels were measured, although they were relatively lower than lipids levels measured in patients with NT-SCC. Conclusion: The present study demonstrated the potential use of in-vivo 1H-MRS to noninvasively assess spectroscopic and metabolic profiles of the healthy tongue tissue in a spatial location-dependent manner. Preliminary results revealed differences between HS and patients with tongue NT-SCC as well as tongue T-SCC, which should be confirmed with more patients. 1H-MRS could be included, in the future, in the arsenal of tools for treatment response evaluation and noninvasive monitoring of patients with tongue SCC.

Investigation of viral etiology in potentially malignant disorders and oral squamous cell carcinomas in non-smoking, non-drinking patients.

Head and neck squamous cell carcinomas (HNSCC) are the seventh most frequent cancers. Among HNSCCs, oral squamous cell carcinomas (OSCCs) include several anatomical locations of the oral cavity, but exclude the oropharynx. The known risk factors for OSCCs are mainly alcohol consumption and tobacco use for at least 75-80% of cases. In addition to these risk factors, Human papillomavirus (HPV) types 16 and 18, classified as high-risk (HR) HPV genotypes, are considered as risk factors for oropharyngeal cancers, but their role in the development of OSCC remains unclear. We tested the hypothesis of viral etiology in a series of 68 well-characterized OSCCs and 14 potentially malignant disorders (PMD) in non-smoking, non-drinking (NSND) patients using broad-range, sensitive molecular methodologies. Deep-sequencing of the transcriptome did not reveal any vertebrate virus sequences other than HPV transcripts, detected in only one case. In contrast, HPV DNA was detected in 41.2% (28/68) and 35.7% (5/14) of OSCC and PMD cases, respectively. Importantly, 90.9% (30/33) of these belonged to the Betapapillomavirus genus, but no viral transcripts were detected. Finally, high-throughput sequencing revealed reads corresponding to transcripts of the Trichomonas vaginalis virus (TVV), which were confirmed by RT-PCR in two OSCCs. Our results strongly suggest that Alphapapillomavirus genotypes classified as HR are not involved in the development of OSCCs in NSND patients and that known oncogenic infectious agents are absent in these specific OSCCs. Any possible direct or indirect role of Betapapillomavirus genus members and TVV in OSCCs remains speculative and requires further investigation.

[Dysfunction of the manducatory apparatus]. / Dysfonction de l'appareil manducateur.

Temporo-mandibular disorders -TMD- involve a whole set of anatomical, physiological and clinical disorders that exceed by far the sole temporo-mandibular joint. The main symptom of this condition, most frequent in female patients, is pain. Three syndromes are associated with TMD: a muscular syndrome, not only involving masticatory muscles but also muscles of the neck and pain in seemingly unrelated anatomical regions, which can be misleading; an inflammatory articular syndrome; a mechanical syndrome affecting mouth-opening path. The main treatment of this very common and benign disorder is based on physical therapy. However, physicians should be warned that some patients might exhibit similar symptoms in rare cases of malignant tumor.

DYSFONCTION DE L'APPAREIL MANDUCATEUR La notion de dysfonction de l'appareil manducateur doit être considérée selon un ensemble anatomoclinique et physiopathologique qui dépasse largement l'articulation temporomandibulaire. Cette symptomatologie essentiellement féminine et douloureuse s'exprime selon trois syndromes volontiers intriqués : un syndrome musculaire qui, au-delà des muscles de la mastication, peut intéresser la musculature cervicale et provoquer des douleurs dont le siège égare aisément le diagnostic ; un syndrome articulaire inflammatoire ; un syndrome mécanique qui altère le chemin d'ouverture de la mandibule. Le traitement est avant tout fonctionnel, s'appuyant sur la rééducation. Mais cette symptomatologie d'apparence et d'étiologie si banales ne doit pas laisser ignorer qu'elle peut avoir une cause plus sombre à type de tumeur maligne régionale.

Lack of efficacy of neoadjuvant chemotherapy in adult patients with maxillo-facial high-grade osteosarcomas: A French experience in two reference centers.

INTRODUCTION: Neoadjuvant chemotherapy (neo-CT) for osteosarcomas is the standard of care. Management of maxillo-facial osteosarcomas (MFOS) is challenging. In this rare disease, we collected a large cohort of patients with the aim to report the histological and radiological local response rates to neo-CT. PATIENTS AND METHODS: All consecutive adult patients treated between 2001 and 2016 in two French sarcoma referral centers (Pitié-Salpêtrière Hospital, APHP, RESAP France and Gustave Roussy Institute France), for a histologically proved MFOS were included. Clinical, histological and radiological data were independently reviewed. Tumor response to neo-CT was assessed clinically, radiologically with independent review using RECIST v1.1 criterion and pathologically (percentage of necrosis). Multivariate analysis was done for outcomes, tumor response and disease-free survival (DFS). RESULTS: A total of 35 high grade MFOS were collected. The clinical tumor response was 4% (1/24 receiving neo-CT), the radiological response was 0% (0/18 with available data) and the pathological response was 5% (1/20 with available data). Three patients (12.5%) initially resectable became unresectable due to clinical and radiological progression during neo-CT. Tumor size and R0 (clear margins) surgical resections were significantly associated with DFS. CONCLUSION: MFOS is a rare disease. This large retrospective cohort of MFOS indicates the lack of benefit and potentially deleterious effects of neo-CT. We suggest privileging primary surgery in initially localized resectable MFOS. The benefit of adjuvant chemotherapy should be prospectively studied.

The parapharyngeal adipose corpus: anatomic and radiologic study.

PURPOSE: Although the morphology of the parapharyngeal adipose corpus (PAC) has been already described, the clinical interest of its volume and weight in the genesis of obstructive sleep apnea syndrome (OSAS) is still controversial. The volume of the PAC has been determined in OSAS patients but not in a normal population. The aim of our study was to investigate the morphology of the PAC by dissection and MRI in a normal population and to determine if there is a relation between the dimensions and volume of the PAC and the Body Mass Index (BMI). METHODS: Thirty hemifaces of 15 fresh cadavers have been dissected after silicone injection with dissection of the external carotid artery and its main branches, with harvesting of the PAC. The PAC has been measured and weighed. Twenty-nine MRI of healthy subjects have been examined to determine the volume of the PAC, the palate-pharynx distance, and epiglottis-pharynx distance. RESULTS: In dissection study the weight of the PAC was 18.57 g ± 2.24, the vertical dimension (height) was 4.61 cm ± 0.51, the frontal dimension (width) was 1.62 cm ± 0.24. The blood supply of the PAC constituted of branches coming from the ascending palatal and ascending pharyngeal arteries. The volume of the PAC on the right side was 1.56 cm3 ± 0.38, on the left side 1.54 cm3 ± 0.37. Its horizontal greater dimension was 1.70 cm ± 0.07. CONCLUSIONS: There is a correlation between the volume of the PAC and the BMI in a normal population. A surgical resection of the PAC in OSAS patients by transoral robotic-assisted surgery can be proposed with preservation of the ascending palatal and ascending pharyngeal arteries.

[Surgery First : prediction for skeletal objectives through structural analysis. Comparison of Sassouni and Delaire analysis]. / Surgery First : détermination des objectifs squelettiques à partir des analyses structurales. Comparaison des analyses de Delaire et de Sassouni.

INTRODUCTION: The purpose of this study was to compare two structural cephalometric analysis (Delaire and Sassouni) as surgical decision tools. These two analyses do not include dental compensation for skeletal discrepancies and have been proven reliable especially for the Sendai surgery first protocol developed by Sugawara. MATERIAL AND METHOD: The two analysis were performed on 20 surgical cases and the proposed skeletal modifications were compared in order to measure the differences and see if those differences varied according to the facial type. For 10 cases the Virtual Surgical Planning (VSP) images obtained from Dolphin 11.95 Premium software (based on the presurgical CBCT and facial photographs) allowed a comparison of the two analyses as surgical decision indicators and to the realised surgical procedure. The VSP photographs obtained were graded by two panels: one professional and the other one non professional. RESULTS: Sassouni's analysis favored more forward movements for the maxilla (ENA +5,45) as well as more vertical modifications (Me 1,595). The facial type did not appear to have a significant effect. The quality of Dolphin VSP prediction was judged rather reliable above average (3.7/6) by the panels. The VSP photographs obtained from the two analyses were presented to the panels as well as the VSP obtained from the actual surgery. The three facial outcomes: Sassouni, Delaire and "Surgery Realised" called Dolphin showed some potentially interesting differences. The small size of the sample did not show any significant findings (t test) but a special analysis revealed a valid difference between the three outcomes. The most aesthetic being Dolphin (surgery realised) 17.4 then Sassouni 16.6 (diff 0.8) and finally Delaire 14 (diff 2.6). CONCLUSIONS: The two structural analysis Delaire and Sassouni did not give the same surgical objectives. Sassouni favored more forward movements for the maxilla as well as more vertical modifications. The Dolphin software appeared to be the quite reliable software to predict the facial outcomes of the surgery. The VSP photographs obtained using Sassouni's analysis were more balanced than when the Delaire analysis was followed (16.4/14 = +2.6). The VSP based on the actual surgery was judged to be even more aesthetic. This shows that beyond a cephalometric analysis the facial aesthetic details and the functional analysis are very important during the phase of surgical planning.

Mandibular advancement reveals long-term suppression of breathing discomfort in patients with obstructive sleep apnea syndrome.

Obstructive sleep apnoea syndrome (OSAS) patients do not report breathing discomfort in spite of abnormal upper airway mechanics. We studied respiratory sensations in OSAS patients without and with mandibular advancement device (MAD). Fifty-seven moderate to severe non obese OSAS patients were asked about breathing discomfort using visual analogue scales (VAS) in the sitting position (VAS-1), after lying down (VAS-2), then with MAD (VAS-3). Awake critical closing pressure (awake Pcrit) was measured in 15 patients without then with MAD. None of the patients reported breathing discomfort when sitting but 19 patients (33%) did when lying (VAS-2: -20% or less). A feeling of "easier breathing" with MAD was observed and was more marked in patients reporting breathing discomfort when supine (VAS-3: +66.0% [49.0; 89.0]) than in those not doing so (VAS-3: +28.5% [1.0; 56.5], p = 0.007). MAD-induced change in awake Pcrit was correlated to VAS-3. In conclusion, MAD revealed "latent dyspnea" related to the severity of upper airways mechanics abnormalities in OSAS patients.

[Benef its of innovation in orthognathic surgery for OSA]. / Place de l'innovation dans la chirurgie orthognathique du syndrome d'apnées obstructives du sommeil.

Obstructive sleep apnea (OSA) is a common, multifactorial disease resulting in high morbidity and mortality. Gold standard treatment is nocturnal positive airway pressure. Maxillomandibular advancement is a surgical technique used to treat obstructive sleep apnea. Development of guided surgery has modified patient care in cases of maxillomandibular dysgnathia. Two case reports illustrate the impact of new technologies on surgical treatment of this condition. New technologies such as the recent development of surgical guides help surgical management.

Immunological and classical subtypes of oral premalignant lesions.

Oral squamous cell carcinoma (OSCC) is a major cause of cancer-associated morbidity and mortality and may develop from oral premalignant lesions (OPL). An improved molecular classification of OPL may help refining prevention strategies. We identified two main OPL gene-expression subtypes, named immunological and classical, in 86 OPL (discovery dataset). A gene expression-based score was then developed to classify OPL samples from three independent datasets, including 17 (GSE30784),13 (GSE10174) and 15 (GSE85195) OPLs, into either one of the two gene-expression subtypes. Using the single sample gene set enrichment analysis, enrichment scores for immune-related pathways were different between the two OPL subtypes. In OPL from the discovery set, loss of heterozygosities (LOH) at 3p14, 17p13, TP53, 9p21 and 8p22 and miRNA gene expression profiles were analyzed. Deconvolution of the immune infiltrate was performed using the Microenvironment Cell Populations-counter tool. A multivariate analysis revealed that decreased miRNA-142-5p expression (P = 0.0484) and lower T-cell, monocytic and myeloid dendritic cells (MDC) immune infiltration (T-cells, P = 0.0196; CD8 T cells, P = 0.0129; MDC, P = 0.0481; and monocytes, P = 0.0212) were associated with oral cancer development in the immunological subtype only. In contrast, LOH at 3p14 (P = 0.0241), 17p13 (P = 0.0348) and TP53 (P = 0.004) were associated with oral cancer development in the classical subtype only. In conclusion, we identified 2 subtypes of OPLs, namely immune and classical, which may benefit from different and specific personalized prevention interventions.

Are elderly patients presenting with squamous cell carcinoma of the oral cavity given the appropriate treatment?

OBJECTIVES: There is no consensus for the specific management of elderly patients presenting with oral cavity squamous cell carcinomas (OC SCC). We report our findings in the treatment of primary OC SCC, for patients of 70 years of age or more, in a French university hospital center. PATIENTS AND METHODS: One hundred and twenty five patients diagnosed between 2000 and 2010, were included retrospectively. Independent risk factors of post-operative complications were identified using a logistic regression. The overall survival (OS) was estimated using the Kaplan Meier method. Independent factors of survival were calculated using a Cox model. RESULTS: The patient's median age was 78. Women presented significantly more premalignant lesions, less alcohol intoxication, and less tobacco consumption. Half of the population sample was staged T4 in the TNM classification. Eighty eight percent of the patients received a curative treatment. The independent risk factors for post-operative complications were T3/T4 stages (OR 4.3 [1.3-14.4]), lymph node metastasis (OR 6.9 [2.1-22.7]), and alcohol abuse (OR 3.5 [1.1-11.0]). The median OS was 14.0 months. The independent negative prognostic factors for OS for patients treated curatively were: age >79 years (HR 1.9 [1.2-3.2]), stage T2/T3/T4 tumor vs. T1 (HR = 3.0 [1.5-6.0], P = 0.001) and substandard surgery (HR = 1.8 [1.1-2.9], P = 0.03). CONCLUSIONS: The management of OC SCC in elderly patients is complex and requires collaboration among gerontologists, surgeons and oncologists. The treatment choice is related to the disease extent and preoperative morbid conditions.

Bibliometric analysis of a century of research on oral erythroplakia and leukoplakia.

BACKGROUND: Oral squamous cell carcinoma is a major cause of cancer-associated morbidity and mortality and may develop from oral erythroplakia and leukoplakia (OEL), the most common oral potentially malignant lesions. Our objective was to provide a descriptive overview of the global research activity on OEL over the past decades. METHODS: We performed a systematic bibliometric analysis of articles and reviews on OEL up to December 31st 2016 using the SCOPUS database. Contribution of each country was analyzed by density-equalizing mapping (DEMP). The overall scientific productivity was analyzed for each journal and country. RESULTS: A total of 5098 published items (articles or reviews) were identified. They are expected to double by 2040, with an expected number of 400 items per year. Only 4% of all research on oral oncology is focused on OEL. Together with the increasing number of publications since 1980s, an increasing number of international collaborative studies were observed. Journal of Oral Pathology and Medicine and Oral Oncology are the leading journals in terms of number of published items. The US, India, and the UK were the most prolific countries in terms of publications overtime. CONCLUSIONS: We identified the leading journals as well as the leading authors and countries contributing to the research on OEL. International collaborative studies in the field are to be encouraged to refine strategies of oral cancer prevention.

Comparative finite element analysis of skull mechanical properties following parietal bone graft harvesting in adults.

INTRODUCTION: Parietal bone grafts are commonly used in cranio-maxillo-facial surgery. Both the outer and the internal layer of the calvarium can be harvested. The bone defect created by this harvesting may induce significant weakening of the skull that has not been extensively evaluated. Our aim was to evaluate the consequences of parietal bone graft harvesting on mechanical properties of the skull using a finite element analysis. METHODS: Finite elements models of the skull of 3 adult patients were created from CT scans. Parietal external and internal layer harvest models were created. Frontal, lateral, and parietal loading were modeled and von Mises stress distributions were compared. RESULTS: The maximal von Mises stress was higher for models of bone harvesting, both on the whole skull and at the harvested site. Maximal von Mises stress was even higher for models with internal layer defect. CONCLUSIONS: Harvesting parietal bone modifies the skull's mechanical strength and can increase the risk of skull fracture, mainly on the harvested site. Outer layer parietal graft harvesting is indicated. Graft harvesting located in the upper part of the parietal bone, close to the sagittal suture and with smooth internal edges and corners should limit the risk of fracture.

Three-dimensional reconstructions of CT scans and cone beam CT of impacted maxillary canines in order to locate areas of ankylosis before orthodontic traction.

PURPOSE: The aim of this study was to model impacted maxillary canines and determine whether areas of ankylosis were present before undertaking orthodontic traction. MATERIAL AND METHODS: Amira/ResolveRT™ software, version 5.0, by FEI Company is a meshing and surface-rendering program that was used to produce three-dimensional reconstructions from CT scans and cone beam images of the impacted canines of 30 patients (10 cone beam files and 20 CT scan files). RESULTS AND DISCUSSION: The presence of zones of ankylosis on the roots of certain impacted canines is revealed by the inversion of the direction of meshing on the tooth surface and on a larger scale by invagination of bone tissue into the tooth tissue at various densities measured in Hounsfield units by the AMIRA™ software program. This observation can guide treatment towards extraction of the impacted tooth, its autotransplantation, or deep alveolar corticotomy, followed by mobilization when the canine is in a vestibular position. CONCLUSION: AMIRA™ software made it possible to detect zones of ankylosis on the roots of certain impacted canines and to adopt a treatment program different from conventional surgico-orthodontic traction. The final aim is to reposition the impacted canine without endangering the adjacent teeth.

A 13-gene expression-based radioresistance score highlights the heterogeneity in the response to radiation therapy across HPV-negative HNSCC molecular subtypes.

BACKGROUND: Radiotherapy for head and neck squamous cell carcinomas (HNSCC) is associated with a substantial morbidity and inconsistent efficacy. Human papillomavirus (HPV)-positive status is recognized as a marker of increased radiosensitivity. Our goal was to identify molecular markers associated with benefit to radiotherapy in patients with HPV-negative disease. METHODS: Gene expression profiles from public repositories were downloaded for data mining. Training sets included 421 HPV-negative HNSCC tumors from The Cancer Genome Atlas (TCGA) and 32 HNSCC cell lines with available radiosensitivity data (GSE79368). A radioresistance (RadR) score was computed using the single sample Gene Set Enrichment Analysis tool. The validation sets included two panels of cell lines (NCI-60 and GSE21644) and HPV-negative HNSCC tumor datasets, including 44 (GSE6631), 82 (GSE39366), and 179 (GSE65858) patients, respectively. We finally performed an integrated analysis of the RadR score with known recurrent genomic alterations in HNSCC, patterns of protein expression, biological hallmarks, and patterns of drug sensitivity using TCGA and the E-MTAB-3610 dataset (659 pancancer cell lines, 140 drugs). RESULTS: We identified 13 genes differentially expressed between tumor and normal head and neck mucosa that were associated with radioresistance in vitro and in patients. The 13-gene expression-based RadR score was associated with recurrence in patients treated with surgery and adjuvant radiotherapy but not with surgery alone. It was significantly different among different molecular subtypes of HPV-negative HNSCC and was significantly lower in the "atypical" molecular subtype. An integrated analysis of RadR score with genomic alterations, protein expression, biological hallmarks and patterns of drug sensitivity showed a significant association with CCND1 amplification, fibronectin expression, seven hallmarks (including epithelial-to-mesenchymal transition and unfolded protein response), and increased sensitivity to elesclomol, an HSP90 inhibitor. CONCLUSIONS: Our study highlights the clinical relevance of the molecular classification of HNSCC and the RadR score to refine radiation strategies in HPV-negative disease.

[Xerostomia]. / Sécheresse buccale (xérostomie).

Xerostomia is a frequent complaint and a real handicap for many patients, often drug-induced. Treatments, even if they are currently unsatisfactory, are aimed at improved oral comfort and quality of life for patients, and to prevent or treat local complications. It consists in humecting buccal mucous membranes with artificial saliva; or in stimulating the glands if functional salivary tissue still exists.