Efficacy of complementary treatment with autologous platelet concentrates and/or mesenchymal stem cells in chemical osteonecrosis of the jaw. Systematic review of the literature.

The aim of this systematic review was to establish the current status of the subject and find out what scientific evidence we have on the use of autologous plasma concentrates (APCs) and mesenchymal stem cells (MSCs) as complementary therapies at the management of Medication-related Osteonecrosis of the jaw (MRONJ). We performed a literature search of articles published between December 2019 to January 2020 in electronic databases, in accordance to PRISMA system. The variables analyzed were: the number of patients, age, sex, medical history, origin of MRONJ, imaging studies, treatment performed, and evolution of MRONJ. The articles included in the review were grouped into two groups (Group A "Therapy with APCs" and Group B "Therapy with APCs and MSCs"). Newcastle-Ottawa scale (NOS) was used to assess the quality of the articles. Fisher's exact test was used to evaluate eventual differences between groups. Of the 306 patients who were included, 297 belonged to Group A and 9 to Group B. In our sample, women predominated against men and no significant differences in age were observed. Osteoporosis was the most frequent underlying disease in both groups. The most common origin of MRONJ was oral surgery in group A. Conservative surgery was performed in all patients, but complementary treatment was applied in different ways in each group. The resolution of the pathology was achieved in 90% of cases in both groups without significant differences between them. The mean score of the reviewed studies at NOS was 4. There are currently no published scientific data that can sufficiently support the use of APCs and MSCs for the treatment of established MRONJs.

Mediastinitis of odontogenic origin. A serious complication with 80 years of history.

We performed a systematic review of the literature about descending necrotising mediastinitis (DNM) of odontogenic origin. In parallel, a retrospective review of this pathology was carried out in an Oral and Maxillofacial Surgery Service of a reference hospital for a population of 1,100,000 inhabitants. The main objectives were to determine changes in mortality and prevalence of this serious complication. The systematic review included 51 articles with 89 patients and our study comprised seven patients. The period of time with the highest number of cases was between 2000-2009 (38 patients). The percentage of mortality observed was 20.2% in diffuse DNM and 4.9% in localised DNM. Thirty-one patients with DNM in our review were admitted for more than 41 days. Despite evidence of a decrease in DNM cases, publications have increased over the years, but it does not appear to be due to an increase in those of odontogenic origin. The survival of DNM has improved since 1998 and remained stable since then. Despite the low prevalence of this disease, multicentre control studies are needed to achieve better evidence about this entity.

The juxta-oral organ of Chievitz (organum yuxtaorale) updated: Embryology, anatomy, function and pathology.

BACKGROUND: The Chievitz's organ or juxta-oral organ is a mysterious bilateral structure, phylogenetically preserved, which develops from the mouth epithelium as an invagination that loses connection to it in the prenatal period. It is located laterally to the walls of the oral cavity in an imprecise anatomical location and receives abundant innervation from the buccal nerve. Structurally it consists of non-keratinizing squamous-like neuroepithelial cells surrounded by two layers of connective tissue with nerve fibers and different morphotypes of sensory corpuscles. Its function is completely unknown although based on its rich innervation it is assumed that works as a mechanoreceptor. METHODS: We have performed immunohistochemistry for axonal and Schwann cells, and the putative mechanoproteins ASIC2, TRPV4 and Piezo2 in sections of fetal juxta-oral organ. RESULTS: Intraparenchymatous nerve fibers and sensory corpuscles were observed as well as immunoreactivity for Piezo2 in both nerve fibers and epithelial parenchymatous cells. CONCLUSIONS: We add indirect evidence that the juxtaoral organ is a mechanoreceptor because in addition to its dense innervation, the epithelial cells and sensory nerve fibers display immunoreactivity for the mechanogated ion channel Piezo2. Based on current knowledge, the functional and clinical importance of the juxta-oral organ should be further investigated.

Medication-related osteonecrosis of the jaw. Implant presence-triggered osteonecrosis: Case series and literature review.

PURPOSE: The aim of this study was to review the characteristics of 'implant presence-triggered osteonecrosis' (IPTO) in the literature and identify possible differences between IPTOs and 'implant surgery-triggered osteonecrosis' (ISTO). MATERIALS AND METHODS: Reviews using PubMed and the Cochrane Database of Systematic Reviews were performed from 2009-2018; the focus was on medication-related osteonecrosis of the jaw (MRONJ) and dental implants. In addition, the hospital records of all patients presented in our department with IPTO were retrospectively reviewed. In both studies, the following data were collected: the number of patients with ISTO or IPTO, age, gender, location, stage of MRONJ, number of implants involved in MRONJ, the elapsed time between the placement of the implants and the development of MRONJ, applied treatment and the presence of mandibular fractures and progress. RESULTS: The literature review provided 111 articles. Nine of the articles were selected for bibliographic review. The number of osteonecrosis cases was significantly higher in the IPTO group (74 cases) compared with the ISTO group (27 cases). The duration of the anti-resorptive treatment (oral and intravenous) was also longer in the IPTO group. In our centre, seven patients with IPTO were chosen; however, no patients with ISTO were selected. The significant differences between the patients in our series and the information collected in the literature for the IPTO group were the time of ingestion of alendronate, the elapsed time from the placement of the implants to the development of the MRONJ and the number of implants linked to the development of a complication. CONCLUSIONS: The use of antiresorptives causes osteonecrosis in patients with implants that are subjected to functional loading, and this occurs at a higher frequency than what is observed after implant placement surgery.

Molecular basis of dental sensitivity: The odontoblasts are multisensory cells and express multifunctional ion channels.

Odontoblasts are the dental pulp cells responsible for the formation of dentin. In addition, accumulating data strongly suggest that they can also function as sensory cells that mediate the early steps of mechanical, thermic, and chemical dental sensitivity. This assumption is based on the expression of different families of ion channels involved in various modalities of sensitivity and the release of putative neurotransmitters in response to odontoblast stimulation which are able to act on pulp sensory nerve fibers. This review updates the current knowledge on the expression of transient-potential receptor ion channels and acid-sensing ion channels in odontoblasts, nerve fibers innervating them and trigeminal sensory neurons, as well as in pulp cells. Moreover, the innervation of the odontoblasts and the interrelationship been odontoblasts and nerve fibers mediated by neurotransmitters was also revisited. These data might provide the basis for novel therapeutic approaches for the treatment of dentin sensibility and/or dental pain.

In vivo behavior of complete human oral mucosa equivalents: characterization in athymic mice.

BACKGROUND AND OBJECTIVE: The interest in tissue engineering as a way to achieve repair of damaged body tissues has led to the carrying out of many studies whose results point to the potential effectiveness of these methods. In a previous study, we reported the obtaining of complete autologous oral mucosa equivalents (CAOMEs), characterized by oral immature keratinocytes and stem cells on an autologous plasma and fibroblast scaffold. The purpose of this study is to show their behavior in vivo, by using them as free grafts in experimental animals, and to demonstrate their potential capacity to regenerate oral mucosa. MATERIAL AND METHODS: We engineered CAOMEs, as previously described. All CAOMEs thus obtained were used as free grafts in nu/nu mice. To assess their evolution in vivo, we studied their histological and immunohistochemical features by using AE1/AE3 pancytokeratin, the 5/6 cytokeratin pair, cytokeratin 13, laminin 5, collagen IV, vimentin, p-63 and Ki-67, at 7, 14 and 21 d. RESULTS: The structure became progressively closer to that of oral mucosa samples. Cytokeratin 5/6 staining became increasingly intense in the basal and suprabasal layers, and cytokeratin 13 was exclusively positive in the superficial layers. The basal membrane was completed in 21 d. Vimentin showed a correct formation of the chorion. The increasingly positive staining of p-63 and Ki-67 indicated that the regeneration process was taking place. CONCLUSION: The present study shows the potential regenerative capacity of the CAOMEs by their ability to reach maturity similar to that seen in oral mucosa.

In vitro engineering of complete autologous oral mucosa equivalents: characterization of a novel scaffold.

BACKGROUND AND OBJECTIVE: Restoration of oral mucosa defects by means of in vitro-cultured equivalents has become a valid alternative in the field of oral and periodontics surgery. Although different techniques have been described, none has been able to provide an equivalent with an autologous scaffold for the epithelium. The purpose of this study was to obtain complete autologous oral mucosa equivalents (CAOME) using the patient's own fibroblasts and plasma and to characterize these equivalents both morphologically and immunohistochemically. MATERIAL AND METHODS: We acquired cell types (keratinocytes and fibroblasts) from the same mucosal samples, which were taken from healthy patients who underwent oral surgery. To construct the CAOME, a small sample of blood was obtained from the patient and subsequently processed to obtain a fibrin glue scaffold. All CAOME thus obtained were stained using the standard hematoxylin and eosin method to study their morphological characteristics. To establish the type of cells in the epithelial layer, CAOME were stained with pancytokeratin AE1/AE3, cytokeratins 5/6 and 13, p-63 and Ki-67. Finally, laminin 5 and collagen IV were used to reveal the presence of a basal membrane. RESULTS: The CAOME featured a monolayer of cube-shaped epithelial cells similar to that found on the basal layer of the oral mucosa. Close to the epithelial layer lay the fibrin and fibroblasts-embedded scaffold. The CAOME was positive to pancytokeratin AE1/AE3, cytokeratin 5/6 and p-63. No reaction was found to cytokeratin 13 and Ki-67. There was staining to laminin 5 but not to collagen IV. CONCLUSIONS: It is possible to engineer a CAOME with an epithelium of basal-like and immature keratinocytes, which could potentially reconstruct in vivo loss of tissue.

Histomorphometric evaluation of guided bone regeneration around implants with SLA surface: an experimental study in beagle dogs.

The aim of this study was to evaluate the efficacy of collagen membranes, either alone or combined with a human demineralized freeze-dried bone allograft (DFDBA) or natural bovine bone graft, in bone defects around dental implants with an SLA (sand-blasted, large grit, acid-etched) surface. The experiments were carried out in three beagle dogs using a split-mouth design. On one side of the jaw, three implants were placed and intra-bony defects were created and covered with a collagen membrane, randomly combined in two of the defects with human DFDBA or inorganic bovine bone graft. A control implant, without membrane covering or defect filling, was also placed. On the other side of the jaw, three implants were placed and the bone defects were treated in a similar fashion, but without membrane covering. The studied variables were the percentage of bone-to-implant contact within the limits of the initial bony defect and percentage of the original bony defect occupied by bone tissue. Although no statistically significant differences were found in this study between the membrane and nonmembrane groups, bone defects augmented with anorganic bovine bone and membranes showed the most promising results from a histological and histomorphometric perspective.

Vascularization of the peroneal muscles. Critical evaluation in fibular free flap harvesting.

This anatomical study was carried out in order to discover the etiology of partial necrosis of the peroneus longus and brevis muscles after fibular osteocutaneous flap harvest. The vascular supply to the lateral compartment peroneal muscles was investigated in 10 fresh cadaveric lower limbs. The peroneal muscles are supplied by two principal sources arteries, the anterior tibial artery (ATA) and the peroneal artery (PA). The ATA is the dominant artery and supplies the proximal and middle thirds of these muscles. The PA is considered to be a supplementary vascular source and supplies the distal thirds of these muscles. After harvesting the PA in a fibular flap, regions of the peroneal muscles preoperatively vascularized by its branches become supplied through the anastomotic "choke" vessels between the ATA and the PA. Primary closure of the cutaneous defect increases the possibility of developing a pseudo-compartment syndrome with necrosis of the more precariously vascularized portions of the peroneal muscles. This complication is difficult to diagnosis early and the reason why we advocate that direct skin closure following composite harvest must be avoided. Moreover, conservation of the inferior and superior lateral branches of the ATA is imperative in order to preserve the peroneal muscles vascularization.

Effect of occlusal splint and transcutaneous electric nerve stimulation on the signs and symptoms of temporomandibular disorders in patients with bruxism.

A crossed-design experimental study has been made involving simple blind paired data and random assignment to treatment, with the aim of evaluating the action of an occlusal splint with transcutaneous electric nerve stimulation (TENS) upon the manifestations of temporomandibular disorders (TMD) in patients with bruxism. The prevalence of TMD in the 24 patients with bruxism was 62.5%%; the corresponding severity, as determined by the pantographic reproducibility index (PRI), was mild (mean value: 20.71). Clicking and pain in the lateral pterygoid muscle were the most frequent clinical manifestations. The occlusal splint and TENS did not significantly improve the signs and symptoms of TMD in these patients with bruxism.

Maxillary undifferentiated carcinoma with rhabdoid features.

The rhabdoid malignant tumor was individualized by Haas et al. as an independent entity within the kidney malignant neoplasms in 1981. From its histopathological characteristics, different cases of rhabdoid extra-renal tumor were documented. This aspect has been also recognized in a wide heterogeneous group of tumors (carcinoma, melanoma, mesothelioma and mesenchymal tumors). The diagnosis of extrarenal rhabdoid tumor is based on the presence of a proliferation of epithelioid cells with large nuclei, prominent nucleoli, abundant eosinophilic cytoplasm, and conspicuous cytoplasmic intermediate filaments, which compress the nuclei. In this article we present the case of a 50-year-old male patient with a malignant maxillary tumor with characteristic rhabdoid features. Its differential diagnosis will be discussed. The literature will also be reviewed.

Intracranial placement of a nasogastric tube after severe craniofacial trauma.

Complications of intracranial placement of a nasogastric tube in patients with complex facial and skull base fractures are infrequent, though the associated morbidity and mortality are high. In such situations some authors advocate craniotomy to allow removal of the tube in several linear segments under direct visualization. Others advise tube removal nasally under antibiotic coverage. We present a case of complex craniofacial fracture in which a nasogastric tube was positioned intracranially 48 hours after admission. The tube was quickly removed through the nose, and the patient was discharged without neurologic problems.

Study of mandibular fracture repair using quantitative radiodensitometry: a comparison between maxillomandibular and rigid internal fixation.

PURPOSE: This prospective study evaluated mandibular fracture repair after either maxillomandibular fixation (MMF) or rigid internal fixation (RIF) using the computer-assisted densitometric image analysis (CADIA) system. PATIENTS AND METHODS: Fifty-two patients, 32 treated by MMF and 20 by RIF, were studied. Five postoperative panoramic radiographs were performed on each patient (immediately postoperatively and at 15, 30, 60, and 90 days) and the changes occurring in the optical density of the bone at and around the fracture line were analyzed. RESULTS: An increase in optic density was observed in both groups at 15 days after treatment. At 30 days, a decrease in optical density was observed in both groups, being significantly greater in the MMF group. In the measurements performed at 60 days, an increased density was found in the RIF group, but the rate of optical density increase was more rapid in the MMF group. During the third month, the rates of optical density increase were similar in the 2 groups. CONCLUSIONS: The use of RIF results in more rapid bone mineralization than the use of MMF.

Traumatic optic neuropathy. A case report.

A case of visual loss following cranio-maxillofacial trauma is reported. The patient had a sudden partial blindness associated with a fracture of the roof, medial and lateral orbital walls. Access to the orbit was achieved through a transethmoidal approach using the Howarth-Lynch medial incision and resecting the bone fragments which impinged on the optic nerve. The patient had total return of visual acuity, without surgical complications. The role of orbital and optic decompression in the management of patients with traumatic optic neuropathy is discussed. Its indications are controversial and the procedure should be considered only within the context of the specific needs of the individual patient.

Stafne bone cyst. Revision of four cases, one of them with bilateral affectation.

Stafne bone cyst of the mandible is the only described destructive bone lesion that is highly localized, nonprogressive, but nonhealing. Such defects usually occur unilaterally, however, bilateral defects are occasionally reported. This paper reports 4 cases of Stafne's bone cyst, one of which showed bilateral presentation. Only four previous cases of bilateral Stafne bone cyst have been reported in the literature. The bibliography is reviewed with regard to the incidence, plausible etiologic factors and methods of diagnosis of such lesions.

Radiodensitometric study of resorption in the site of mandibular fractures.

PURPOSE: The area of bone resorption resulting from a fracture varies widely. This study was performed to determine the magnitude of this area in mandibular fractures by means of quantitative radiodensitometry and to determine the influence of the kind of treatment applied, location of fracture, and the age and sex of the patient on this zone. PATIENTS AND METHODS: In successive panoramic radiographs after mandibular fracture (postoperatively and at 15, 30, 60, and 90 days), optical density changes occurring in the region of the fracture were analyzed. An area of 2 cm on each side of the fracture was studied, divided into 31 concentric regions of equal size (4 pixels thick). RESULTS: The magnitude of the area of necrosis in mandibular fractures is 7.7 mm in cases treated by maxillomandibular fixation and 5.8 mm in those cases treated with rigid internal fixation. CONCLUSIONS: The area of resorption in mandibular fractures is determined, in part, by the type of treatment used and the location of the fracture.