Bone characteristics in condylar hyperplasia of the temporomandibular joint: a microcomputed tomography, histology, and Raman microspectrometry study.

Unilateral condylar hyperplasia (UCH) of the temporomandibular joint is a progressive deformation of the mandibular condyle of unknown origin. UCH is characterized by excessive growth of the condylar head and neck, leading to an increase in size and volume. The aim of this study was to investigate the characteristics of the bone in patients with UCH using microcomputed tomography (micro-CT), histology, and Raman microspectroscopy. The mandibular condyles of six patients with UCH were analysed using micro-CT, histology, and Raman microspectrometry and imaging, and the results were compared with those obtained for a normal control subject. Three-dimensional micro-CT models revealed focal abnormalities of the bone microarchitecture, with foci of osteosclerosis. Histological sections showed that these foci included islands of calcified cartilage matrix with live chondrocytes. Raman analysis revealed that the cartilage matrix was more heavily calcified than the bone matrix and that the cartilage could be identified by the phenylalanine (PHE) band of its matrix, as well as by its glycosaminoglycan (GAG) content. The persistence of foci of live and active chondrocytes within the bone matrix is intriguing and appears to be pathognomonic of UCH. These new findings on UCH could help to determine its pathophysiology and thus prevent this disease, which can lead to major facial deformity.

Significant decrease of facial cellulitis admissions during COVID-19 lockdown in France: A multicentric comparative study.

During the 2020 coronavirus pandemic, a lockdown was imposed in France during the first wave. An apparent decrease in incidence of cellulitis of odontogenic origin was noticed then. This study aimed to compare the incidence of cellulitis during this extraordinary period with the same period in 2018 and 2019, based on retrospective multicentric data. All maxillofacial surgery departments in French public hospitals were contacted. Responders were asked to include all patients admitted for the surgical drainage of a head and neck abscess of odontogenic origin during the first 2020 lockdown period, and in a similar time frame in 2018 and 2019 (control group), based on screening the French diagnostic and therapeutic classification of medical acts. We report a 44% significant nationwide decrease in the incidence of admissions for cellulitis. There were 187 patients in 2020 for 334 and 333 patients in 2018/2019 respectively. The reasons to explain this finding are hypothetical (organizational reasons leading to earlier management, patients' fear to seek for medical management, usual excess in surgical indications or concomitant decrease of non-steroidal anti-inflammatory drugs delivery). Whatever the explanation, it would be of great interest to find it out in order to improve the prevention of cellulitis.

Cavernous venous malformation of the lacrimal gland.

BACKGROUND: Cavernous venous malformation (CVM) is a common benign vascular lesion of the orbit. It was previously known as "orbital cavernous hemangioma". Localization within the lacrimal gland is extremely rare. CASE PRESENTATION: We describe the case of a 76-year-old man with an asymptomatic CVM of the left lacrimal gland incidentally discovered on a routine MRI. A curative and diagnostic en bloc surgical resection was performed, allowing for histological diagnosis. CONCLUSIONS: CVM of the lacrimal gland is extremely rare and usually asymptomatic. Proptosis is the main symptom. On MRI, the lesion appears hypointense with heterogeneous enhancement after Gadolinium injection on T1-weighted imaging and hyperintense on T2 STIR-weighted imaging. Histological examination is mandatory for the diagnosis. Surgical resection is usually performed.

Medication-related osteonecrosis and osteoradionecrosis of the jaws: Update and current management.

Medication related osteonecrosis of the jaws (MRONJ) and osteoradionecrosis of the jaws (ORNJ) are two different diseases of quite similar appearance. MRONJ is mainly due to antiresorptive or antiangiogenic drug therapy and ORNJ to radiotherapy. The present work aimed at presenting and comparing the current knowledge on MRONJ and ORNJ. They both present as an exposure of necrotic bone and differ in some clinical or radiological characteristics, clinical course and mostly in treatment. They share similar risk factors. A tooth extraction is more frequently found as a triggering factor in MRONJ. The frequency of a maxillary localisation seems higher for MRONJ. On computed tomographic images, a periosteal reaction seems characteristic of MRONJ. More frequent pathological fractures seem to occur in ORNJ. It is mandatory, for ORNJ diagnosis, to exclude a residual or recurrent tumour using histological examination. Both MRONJ and ORNJ are challenging to treat and cannot be managed similarly. For both, it would still be worth to optimise awareness within the medical community, patients' oral hygiene and dental cares to improve their prevention and make their incidences decrease. Conservative therapy is more frequently achieved for MRONJ than ORNJ and surgical resection is more often performed for ORNJ. For both diseases, the last treatment possible in refractory cases is a surgical extensive resection with free flap reconstruction. A MRONJ classification is widely used today, whereas no consensus exists to date for ORNJ classification. We propose a classification that could play this role.

Impact of the COVID-19 lockdown on the epidemiology of maxillofacial trauma activity: a French multicentre comparative study.

The coronavirus disease 2019 (COVID-19) outbreak has had a major impact on medical and surgical activities. A decline in facial trauma incidence was noticed during the lockdown period. The aim of this study was to evaluate the decline in maxillofacial trauma in France during this particular period. A retrospective multicentre comparative study was initiated in 13 major French public hospital centres. The incidence of facial trauma requiring surgery during the first month of lockdown was compared to that during equivalent periods in 2018 and 2019. Differences in the types of trauma were also analysed. Thirteen maxillofacial departments participated in the study. A significant decline in maxillofacial trauma volumes was observed when compared to equivalent periods in 2018 and 2019 (106 patients compared to 318 and 296 patients, respectively), with an average reduction of 65.5% (P=0.00087). The proportion of trauma due to sports and leisure was reduced when compared to reports in the literature. As a consequence, in the context of a pandemic, the material and human resources related to this activity could be reallocated to the management of other pathologies that cannot be postponed.

An extremely rare case of a displaced third molar into the infratemporal fossa associated with a textiloma.

BACKGROUND: Third molar extraction is one of the most common procedures performed by oral surgeons, however with rare complications. The accidental displacement of a maxillary third molar into the infratemporal fossa (ITF) is a rare complication that can occur even with experienced surgeons. CASE PRESENTATION: We describe the case of a 17-year-old patient whose right upper third molar was accidentally pushed to the ITF associated with a cellulitis and the late discovery of a textiloma (a surgical gauze). CONCLUSIONS: Extraction of third molars is a safe surgical procedure when performed in appropriate conditions. The diagnosis of textiloma following a maxillo-facial surgery is extremely rare. It is important to take into account this possibility in order to avoid delaying treatment when it occurs.

Anatomical and functional rehabilitation after total bilateral maxillectomy using a custom-made bone-anchored titanium prosthesis.

Surgical reconstruction after a total maxillectomy remains challenging. The standard treatment is the microvascular free flap. In cases of surgical contraindication, oral rehabilitation is usually performed with a palatal obturator prosthesis (PAP). Acceptable anatomical and functional outcomes in terms of speech, mastication, aesthetic appearance, stability, and comfort are not often achieved with a PAP. This technical note describes a technique for reconstruction after total bilateral maxillectomy involving the implantation of a custom-made bone-anchored titanium prosthesis obtained by 3D printing. Good functional and anatomical outcomes were achieved with this technique. It combines the advantages of the obturator prosthesis (short duration of surgery and hospitalization, low morbidity) and free flap (aesthetic/anatomical reconstruction and irremovable comfortable functional rehabilitation). This technique constitutes a new therapeutic alternative for the restoration of large defects after total maxillectomy when free flaps are contraindicated.

Alveolar distraction osteogenesis of a fibula free flap in maxillary reconstruction.

In maxillary reconstruction, it is challenging to obtain satisfactory maxillary projection and to optimizate the dental implant-prosthetic rehabilitation. We report a case of sagittal distraction of a fibula free flap used to reconstruct maxilla after a ballistic trauma. Distraction began seven days after implantation of the device. The distraction protocol was 0.9mm per day during a total period of 2 months. Cone beam computed tomography acquisitions were performed at 3 months after the end of the distraction. The distractor device was removed 5 months after the end of the distraction protocol to allow bone consolidation. A satisfactory total distraction of 7mm was obtained with an esthetic variation of the projection of the upper lip and closure of the nasolabial angle.

Associated relaps factors in Le Fort I osteotomy. A retrospective study of 54 cases.

PURPOSE: The Le Fort I osteotomy (LFI) procedure is commonly used to restore morpho-functional balance. The goal of maxillofacial surgeons with this procedure is to achieve occlusal stability. To identify factors associated with relapse after maxillary advancement in cleft lip and palate patients, the one-year post-operative stability of Le Fort I osteotomy was evaluated. METHODS: Horizontal and vertical relapse were analysed on lateral cephalograms by retrospectively using tracing paper in an orthonormal landmark in 54 patients undergoing unilateral cleft lip and palate surgery who were monitored at Nantes University Hospital. The lateral cephalograms were performed pre-operatively, immediately post-operatively, and after one year. Several variables were studied such as population data, intra-operative and post-operative surgical treatment, and surgical movement. RESULTS: At point A, the subspinale point, the mean advancement during surgery was 4.2 mm, with a relapse of 0.8 mm (20.1%). The mean downward movement was 2.0 mm in 26 patients who had a clockwise rotation of the maxilla, with a relapse of 0.6 mm (28.4%). The mean upward movement was 2.3 mm in 27 patients who had a counterclockwise rotation, with a deterioration of 0.2 mm (7%). A 7-millimetre surgical advancement corresponded to the threshold value beyond which relapse appeared to be significantly greater but still less than two millimetres in 75% of cases. CONCLUSION: The degree of advancement appears to be the only variable correlated with the amplitude of the relapse.

The mucous cyst, a rare and delayed complication after rhinoplasty.

INTRODUCTION: Rhinoplasty is frequently performed worldwide, and patients and surgeons both expect good cosmetic results without any deformity recurrence. We report a rare case of mucous cyst occurred after post-traumatic rhinoseptoplasty. OBSERVATION: A 27-year old woman presented a median mass of the nose root 7 years after prior rhinoseptoplasty. Investigations showed a subcutaneous lesion of 10.5×24.5mm. The surgery consisted on an external rhinoplasty allowing cyst removal, bilateral osteotomies and reconstruction of the nasal dorsum by deep temporal fascia graft. Histological examination confirmed the diagnosis of begnin mucous cyst. No recurrence was observed at 1-year follow-up. DISCUSSION: Mucous cyst post rhinoplasty is rare and is probably due to accidental mucosal material implantation into the subcutaneous plane during rhinoplasty. This complication can be avoided by adequate infiltration and hydrodissection, careful dissection, and avoidance of unnecessary trauma during osteotomies.

Microcomputed tomography (microCT) and histology of the mandibular canal in human and laboratory animals.

The inferior alveolar nerve (IAN) is a sensitive branch of the trigeminal nerve. It has an intra-bone path in the mandible, inside the mandibular canal, where it is accompanied by lymph, venous and arterial vessels. We have studied the mandibular canal in human mandibles and in some laboratory animals (mice, rats, rabbits and cats). Microcomputed tomography evidenced that the walls of the canal are made with thin plates of trabecular bone with numerous fenestrations. This aspect is evidenced in dentate subjects and become more evident in edentulous subjects with atrophy of the alveolar bone. In rats and mice, the wall of the canal is also clearly composed of trabecular plates coming from the surrounding alveolar bone of the mandible. In the rabbit, similar findings are also observed but the trajectory of the canal is more difficult to identify. In the cat, the floor of the canal is composed of the cortical bone from the basilar cortex of the mandible and the roof has a trabecular nature. Vascular injections of gelatin-barium evidenced the arterial trajectories inside the bone in rats and humans. Undecalcified bone sections in human evidenced the histological aspect of the IAN and its connective sheets. Some nervous bundles can be observed outside the epineurium. Bone remodeling is observed on the wall of the mandibular canal. These descriptive findings have a clinical relevance in dental implantology or mandibular surgery.

Cholesterol granuloma of the maxilla.

Intra-osseous cholesterol granuloma (CG) is a rare and benign lesion. Very few cases of CG of the jaws have been described in the literature. CG of the jaws seems to be due to the accumulation of cholesterol of hematogenous origin in odontogenic cysts. We report on one case of CG of the maxilla treated by surgical enucleation in a 46-year-old man who presented an asymptomatic swelling of the maxilla.

A rare location for a common tumor: Lingual lipoma.

Lipomas are the most common benign tumors in human body but their occurrence in the oral cavity is very rare. They present as a slow growing, yellowish submucosal and painless mass. The treatment consists of a simple surgical excision. The histopathologic examination confirms the diagnosis. We present a case of tongue lipoma.

[Temporo-mandibular ankylosis]. / L'ankylose temporo-mandibulaire.

Ankylosis of the temporomandibular joint is defined as a permanent constriction of the jaws with less than 30mm mouth opening measured between the incisors, occurring because of bony, fibrous or fibro-osseous fusion. Resulting complications such as speech, chewing, swallowing impediment and deficient oral hygiene may occur. The overall incidence is decreasing but remains significant in some developing countries. The most frequent etiology in developed countries is the post-traumatic ankylosis occurring after condylar fracture. Other causes may be found: infection (decreasing since the advent of antibiotics), inflammation (rheumatoid arthritis and ankylosing spondylitis mainly) and congenital diseases (very rare). Management relies on surgery: resection of the ankylosis block in combination with bilateral coronoidectomy… The block resection may be offset by the interposition temporal fascia flap, a costochondral graft or a TMJ prosthesis according to the loss of height and to the impact on dental occlusion. Postoperative rehabilitation is essential and has to be started early, to be intense and prolonged. Poor rehabilitation is the main cause of ankylosis recurrence.

[Inferior alveolar nerve reconstruction after segmental resection of the mandible]. / Réhabilitation sensitive du nerf alvéolaire inférieur après mandibulectomie interruptrice.

INTRODUCTION: The sacrifice of inferior alveolar nerve (IAN) is usual in case of resection of mandibular tumors and is responsible for disabling sensory disorders, drooling and lip incompetence. We report the case of a reconstruction of the IAN by means of an autologous nerve graft after segmental resection of the mandible. OBSERVATION: A 27-year-old man presented with a recurrence of mandibular ameloblastoma. Treatment consisted in segmental mandibulectomy with resection of the IAN. Bone reconstruction was performed with a fibula free flap and IAN reconstruction was obtained by mean of a 7-cm nerve graft obtained from the greater auricular nerve (GAN). At the 6th postoperative month, the patient had recovered a normal sensitivity of his lower lip and chin. Latency of somatosensory evoked potentials was similar for both sides. DISCUSSION: The repair of the IAN by nerve autograft is a simple procedure that allows for good sensitive rehabilitation. The use of the GAN is well suited from its anatomy and from the moderate ear sensory sequelae.

Facial features in Harlequin ichthyosis: Clinical findings about 4 cases.

We report 4 cases of Harlequin ichthyosis, which is a rare and severe congenital ichthyosis involving the face. Facial appearance consists in severe ectropion, conjonctival edema, eclabium, flattened ears, broadened nose and large, thick, plate-like skin scales. Recent advances in neonatal care have been made, such as retinoid therapy, and have led to an increased survival rate. Early surgical correction of ectropion may be required because of ocular complications.