Burning Mouth Syndrome: Aetiopathogenesis and Principles of Management.

Burning mouth syndrome (BMS) is a chronic debilitating oral condition characterised by a burning sensation of the oral mucosa in an otherwise apparently normal person. Its aetiology and pathogenesis are obscure, but both psychogenic factors and peripheral and central neuropathies appear to be implicated. There is no cure for BMS, and treatment with either local or systemic medications focuses on the relief of symptoms and on improving quality of life. In recalcitrant cases, psychological/psychiatric intervention may be helpful. In order to improve treatment outcomes, a better understanding of the pathogenesis of this syndrome might provide a basis for the development of more effective management strategies. In this short review, we discuss current knowledge of the diagnosis, aetiopathogenesis, and management of BMS.

Postherpetic Neuralgia and Trigeminal Neuralgia.

Postherpetic neuralgia (PHN) is an unpredictable complication of varicella zoster virus- (VZV-) induced herpes zoster (HZ) which often occurs in elderly and immunocompromised persons and which can induce psychosocial dysfunction and can negatively impact on quality of life. Preventive options for PHN include vaccination of high-risk persons against HZ, early use of antiviral agents, and robust management of pain during the early stage of acute herpes zoster. If it does occur, PHN may persist for months or even years after resolution of the HZ mucocutaneous eruptions, and treatment is often only partially effective. Classical trigeminal neuralgia is a severe orofacial neuropathic pain condition characterized by unilateral, brief but recurrent, lancinating paroxysmal pain confined to the distribution of one or more of the branches of the trigeminal nerve. It may be idiopathic or causally associated with vascular compression of the trigeminal nerve root. The anticonvulsive agents, carbamazepine or oxcarbazepine, constitute the first-line treatment. Microvascular decompression or ablative procedures should be considered when pharmacotherapy is ineffective or intolerable. The aim of this short review is briefly to discuss the etiopathogenesis, clinical features, and treatment of PHN and classical trigeminal neuralgia.

Oral mucosal melanoma: some pathobiological considerations and an illustrative report of a case.

Oral mucosal melanoma is a relatively rare malignancy with an aggressive clinico-pathological behaviour. The mean 5-year survival rate is about 15 %. It arises primarily from melanocytes found in the basal cell layer of the epithelium, but may sometimes arise from melanocytes residing in the lamina propria. The pathogenesis is complex, and few of the molecular mechanisms underlying the development of oral mucosal melanoma have been defined. The extraneous risk factors associated with oral mucosal melanoma, if any, are unknown. Oral mucosal melanomas account for about 25 % of all mucosal melanomas of the head and neck, and exhibit a profile of cytogenetic alterations, and a pathobiological behaviour and clinical course different from that of cutaneous melanomas. As they are usually painless and grow quickly, as a rule, they are diagnosed late in the course of the disease when the lesions are already large and have metastasized to regional lymph nodes. In this paper we discuss some aspects of the pathobiology of oral mucosal melanoma, and present an illustrative case report.

Osseointegration: biological events in relation to characteristics of the implant surface.

Osseointegration of titanium implants is a complex biological process involving interactions between immuno-inflammatory responses, angiogenesis and osteogenesis, all of which are influenced by the physical and chemical characteristics of the implant surface. An implant surface with moderately rough topography and high surface energy influences cellular activities, enhancing peri-implant bone wound healing. Primary mechanical stability of the implant is essential for osseointegration. In this article we review some of the more important biological events of peri-implant bone wound healing in the process of osseointegration, and discuss how the biophysical properties of implant surfaces influence cellular responses.

Oral medicine case book 64: Some aspects of the pathophysiology of angioedema with special reference to the upper aerodigestive tract.

Angioedema refers to a localized oedematous swelling of subcutaneous or submucosal tissues, caused by dilatation and increased permeability of blood vessels, usually mediated either by histamine or by bradykinin. Deficiency or loss of functional activity of the complement component C1 esterase inhibitor (C1-INH) affects multiple systems, including the kallikrein-kinin, complement, coagulation and fibrinolytic pathways, and in the context of angioedema, the result is increased production and release of bradykinin and other vasoactive substances such as C3a. Owing to impairment of C1-INH, factors Xlla and kallikrein, by a positive feedback mechanism, bring about persistent activation of the kallikrein-kinin pathway with amplification of production of bradykinin, resulting in angioedema. Histamine can cause histaminergic angioedema. As the name implies, this oedema is caused by degranulation of mast cells/basophils as a result of an IgE-dependant allergic reaction to extracts of food, drugs, infectious agents, or to physical stimulation; or as the result of direct degranulation of mast cells/basophils independently of IgE, caused by releasing agents such as opiates, antibiotics or radiocontrast media. As dental, oral and maxillofacial operative procedures may trigger the development of angioederria in susceptible individuals, the dental practitioner should be familiar with its

Oral mucosal immunity.

Oral keratinocytes and dendritic cells of the oral mucosa, through molecular pattern recognition receptors, distinguish between commensal and pathogenic microorganisms and mediate the generation of protective immunoinflammatory responses to potentially invading pathogens or mediate immune tolerance toward commensal microorganisms. Oral immune tolerance is the result either of lack of activation of T cells in response to immunogenic presentation of antigens or of suppression of activity of effector T cells by regulatory T cells. Secretory immunoglobulin A (sIgA) antibodies at oral mucosal sites contribute to oral immunity by limiting colonization of microorganisms and their invasion of the epithelium. Ig isotype class switching to IgA is either dependent on or independent of T helper cells and is facilitated by cytokines secreted by dendritic cells and monocytes.

Alveolar ridge preservation immediately after tooth extraction.

Ridge preservation procedures immediately after tooth extraction, are commonly used with a view to minimising remodelling and shrinkage of the alveolar ridge, associated with socket healing. These procedures may sometimes be effective, but they cannot completely prevent reduction in dimension of the ridge. Certain biomater als used may actually hamper normal deposition of bone within the healing socket, reducing bone trabeculae that can integrate with the implant surface. However, in extraction sockets in alveolar ridges of low bone density, particles of implanted bone substitute incorporated in the healing bone, may enhance the mechanical support for the implant, provided by normal healed bone of low trabecular density alone. This paper reviews biological rationales and procedures for ridge preservation immediately after extraction and comments on their clinical use.

Bisphosphonate-related osteonecrosis of the jaw.

Bisphosphonates are agents commonly used in the treatment of osteoporosis, and in the management of metastatic bone disease, and of hypercalcaemia of malignancy. Any oral surgical procedure or traumatic event exposing bone to bacterial infection may precipitate osteonecrosis of the jaw in subjects who have been treated with bisphosphonates which suppress bone turnover and inhibit the angiogenesis associated with healing. New guidelines for the treatment of bisphosphonate-related osteonecrosis of the jaw are emerging, but hitherto treatment has been empirically conservative.

A better view of the temporomandibular joint: a technical note.

The authors present a method of gaining access to the temporomandibular joint that improves visibility and surgical access. It should reduce operating times and improve results.

A short account of cancer--specifically in relation to squamous cell carcinoma.

Cancer is the outcome of a complex multifactorial process of cytogenetic and epigenetic changes that affect cell cycle progression, apoptosis, DNA repair mechanisms and cell differentiation. Cancer cells have the capacity to evade the immune system, to invade tissues and to metastasize. Cancer is treated by surgery, chemotherapy and radiotherapy, each as single treatment modalities or more often in combination. Failure of treatment to cure a patient of cancer may be owing to the fact that radiotherapy and chemotherapy can eradicate transit-amplifying cells which are characterized by uncontrolled proliferation and prolonged survival; but cannot eradicate all cancer stem cells that divide slowly, have a relatively unlimited self-renewal capacity and express anti-apoptotic genes; and also owing to the fact that surgery cannot always eliminate occult fields of pre-cancerization.

Adenomatoid odontogenic tumour: review of the literature and an analysis of 33 cases from South Africa.

The adenomatoid odontogenic tumour (AOT) is a benign lesion of odontogenic origin. It is a slow growing tumour that results in a painless expansion of the jaws. This is a retrospective review of the demographic, clinical and radiographic features of AOTs diagnosed in a black South African population over 20 years. Of the 746 odontogenic tumours diagnosed, 4% were AOTs. The patients' ages ranged from 9 to 37 years with a mean age of 15 years. The highest incidence was in the second decade of life (85%). The female to male ratio was 5.6:1. The maxilla was more commonly affected than the mandible in a ratio of 1.5:1. The sizes of the lesions ranged from 2 to 7cm, with 60% involving an entire quadrant. All were of the central follicular type and appeared as well-demarcated radiolucent lesions. The canine was the most common impacted tooth. The treatment of choice was enucleation of the lesion, with no recurrences being reported.

Osteosarcoma of the jaw. A brief review and a case report.

Osteosarcoma of the jaws accounts for 6-13% of all osteosarcomata. If not diagnosed early, it spreads extensively through the jaw and contiguous soft tissues into the nasal cavity, the maxillary sinus, the orbit and the infratemporal fossa, and may invade the oral soft tissues. A clinical finding of tooth displacement and tooth mobility associated with radiolucency/radiopacity should alert the practitioner to the possibility of osteosarcoma or some other malignancy.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia: review of the literature and report of a case.

This article documents an additional case of a rare syndrome, reported only in black persons in South Africa. It is characterised by hamartomatous atypical follicular hyperplasia with central odontogenic fibroma (WHO-type)-like features attached to multiple impacted teeth, and with generalized enamel dysplasia showing features of hypoplastic amelogenesis imperfecta. Other features associated with the syndrome, but not present in all reported cases, include open-bite malocclusion, gingival overgrowth, hypodontia, pulpal calcifications and aberrant root formation of the unerupted teeth. Our present case shows the additional feature of impacted supernumerary teeth. As we cannot find any reports in the literature of the occurrence of amelogenesis imperfecta-like enamel dysplasia associated with hamartomatous follicular hyperplasia showing the features of WHO-type central odontogenic fibroma, with or without the additional features mentioned above, we propose to name this syndrome Enamel Dysplasia with Hamartomatous atypical Follicular Hyperplasia (EDHFH) syndrome.

A clinical evaluation of dry sockets at the Medunsa Oral Health Centre.

Dry sockets, or alveolar osteitis, is one of the most common postoperative complications following the extraction of teeth. For the patient this is often a very painful and distressing condition. Most dental practitioners will experience this complication at some or other stage of their career. The aetiology of dry socket is multifactorial with several predisposing factors having been identified. The aims of this study were to assess the incidence of dry sockets at the Medunsa Oral Health Centre, to assess the demographic details of these patients and to explore the predisposing factors for the development of dry socket. It is hoped that this will help to minimize or prevent this condition from occurring. This was a prospective study conducted over an eight-month period in the Department of Maxillofacial and Oral Surgery, University of Limpopo, Medunsa Campus. The data was collected by means of a structured questionnaire. Of the 4077 patients that presented for dental extractions, 2% (79) developed a dry socket. The ages of the patients ranged from 12-79 years with a mean age of 35 years. There was a slight female preponderance (1.5:1). The mandibular second molar was the most common site to be affected (22%). Pain was the most common presenting symptom. Underlying systemic conditions were found in 19% of the patients, while 25% smoked, consumed alcohol or both. Identifying risk factors, attention to procedural details and patient education were found to be important in the prevention of dry socket.

Diffuse infiltrative CD8+ lymphocytosis syndrome: review of the literature and report of a case.

Diffuse infiltrative lymphocytosis syndrome (DILS) is an uncommon manifestation of HIV infection characterised by persistent circulating CD8+ lymphocytosis accompanied by visceral lymphocytic infiltration. The lungs and the salivary glands are the most common organs involved. Parotid enlargement in HIV-seropositive subjects may represent HIV-associated lymphoepithelial lesions, hyperplastic lymphadenopathy, lymphoma, bacterial and viral infections, Sjögren's syndrome and DILS. Therefore confirmatory histopathological diagnosis and immunohistochemical analysis following a biopsy is essential to determine the exact nature of the salivary gland enlargement. A review of the literature of DILS and a description of a typical case of bilateral cystic lymphoepithelial lesions of the parotid glands, in an HIV-seropositive subject with DILS, is presented.

Orbital abscess as a complication of odontogenic infection. A case report and review of the literature.

Orbital abscess is a rare complication of odontogenic infection. This report describes a case of an orbital abscess in a 42-year-old HIV-seropositive woman who developed this condition as a complication by direct spread via the maxillary sinus of a dento-alveolar abscess of the maxillary first premolar, resulting in the loss of her eye.

Intraorbital plexiform neurofibroma in an NF-1-negative patient.

A 52-year-old patient presented with an orbital swelling and exophthalmos that enlarged over a period of about 40 years. The clinical examination showed massive exophthalmos and ptosis of the right eye without diplopia. The radiological investigation (MRI, CT and ultrasound) showed an unclear intraorbital mass with erosion of the orbital floor, infraorbital rim and orbital roof. The lesion was diagnosed histologically as a plexiform neurofibroma. The patient did not present any features of neurofibromatosis type 1 (NF-1) and molecular genetic analysis was unable to uncover a pathogenic sequence alteration in the NF-1 gene. Owing to the absence of clinical and ophthalmologic symptoms and the improbability of complete removal, the patient refused surgical intervention.

A report of oral extramedullary acute myeloid leukaemia (AML) in an 8-year-old girl with newly diagnosed AML-M4Eo.

Acute myeloid leukaemia (AML), characterized by proliferation of immature neoplastic myeloid cells, is uncommon in childhood. We present a case of an 8-year-old girl with AML-M4Eo who had an extramedullary leukaemic tumour in the oral cavity.

Herpes zoster post-herpetic neuralgia.

Post-herpetic neuralgia (PHN) is the most frequent complication of herpes zoster and often results in significant morbidity and a reduction in the patient's quality of life. The peripheral nerve injury that occurs during the acute phase of herpes zoster (HZ) leads to an abnormal tonic impulse discharge from primary nociceptive afferent neurons which induce slow temporal summation. This "wind-up" phenomenon is responsible for continuous partial depolarisation of second-order neurons with increased spontaneous impulse discharge and expanded receptive fields within the dorsal horn nociceptive neurons. The abnormal central processing involves the activation of N-methyl-D-aspartate (NMDA) receptors resulting in neuropathic pain, characterized by spontaneous pain, hyperalgesia and allodynia which is typical of PHN. In addition, tonic input from non-nociceptive AB afferent neurons, maintained by sympathetic efferent activity, contribute to the development and maintenance of neuropathic pain in general, and a burning sensation in particular.

Calcifying epithelial odontogenic tumor with intracranial extension: report of a case and review of the literature.

The calcifying epithelial odontogenic tumor (CEOT) is a rare benign neoplasm, possibly of stratum intermedium origin and occurring predominantly in the mandible of adults. The treatment varies, depending on its size, location, and histology. A case of an advanced CEOT arising in the maxilla with intracranial extension is reported. The report is supplemented by a review of the literature.