There are currently two distinct contexts in which the term 'periodontal medicine' is used - one that describes the study of the systemic effects of inflammatory periodontitis and another (the main focus of this volume) that describes periodontal tissue manifestations of systemic diseases. These two disciplines are distinctly different in their scope, method of study and impact on our patients and thus our clinical practice, and yet they are frequently confused. The title 'periodontitis and systemic disease' better describes the peripheral effects of periodontal bacteria and periodontal inflammation on the onset, clinical course and outcome of diseases of the body's major systems, such as the cardiovascular and cerebrovascular systems, metabolic control in people with diabetes, adverse pregnancy outcome, osteopaenia/osteoporosis and respiratory diseases. Whilst a body of evidence is developing globally to support a link between plaque-induced inflammatory periodontal disease (periodontitis) and some of the above conditions, a lack of prospective intervention studies that assess the impact of successful periodontal therapy on systemic disease outcomes currently limits these relationships to 'associations'. Intervention studies allow us to shed light on true causality or disease modification, but such studies have a long time-course and are thus expensive to run. However, the shorter time-course involved in studying the impact of periodontal therapy on adverse pregnancy outcome is such that studies like the currently active Oral Conditions and Pregnancy study in the United States should help clarify the nature of the periodontitis/adverse pregnancy outcome relationship in the near future. The term 'periodontal medicine' should be applied in a more focussed manner to the study of nonplaque- induced lesions affecting the periodontal tissues and systemic diseases and conditions that present with periodontal tissue manifestations. These largely involve the gingival tissues and associated muco-gingival complex, but may also involve the periodontal attachment, including alveolar bone. They represent a fascinating array of diseases and disorders, which present the clinician with often complex diagnostic challenges and a need for medical (and more rarely surgical) management, that frequently necessitates the establishment of collaborative care pathways with physicians in disciplines as diverse as dermatology and gastroenterology. There are far in excess of 100 such conditions, and the scope of this traditionally 'Cinderella' field of clinical practice is vast. Often these conditions are overlooked or misdiagnosed, due to the frequently subtle nature of presenting clinical signs, the existence of multiple pathology and the need for a forensic approach to the investigative process. This volume presents a focus article on the condition desquamative gingivitis to whet the reader's appetite and follows up with a series of illustrated clinical reports and a case conference. We hope that, having read this volume, you will be stimulated to learn more about this important and emerging clinical sub-discipline of periodontal practice. There are large numbers of our patients who suffer from these conditions, but if we don't look for the signs, we will not find the diseases. For readers who wish to learn more about periodontal medicine, the Quintessence textbook Periodontal Medicine: A Window on the Body (ISBN 1-85097-079-3) will be available in October 2005.

Much attention has recently been given to possible links between maternal periodontitis and pregnancy outcome. This paper aims to explore the potential explanatory mechanisms for such links, and the evidence from both in vitro and animal studies to support these concepts. Potential mechanisms rely on the role of proinflammatory molecules involved in the normal physiological process of parturition being influenced by distant or local inflammatory processes caused by infections in maternal tissues. However, there are a number of shared risk factors that may complicate analyses of any such relationship.

Keywords: periodontitis, pregnancy, complications, periodontal treatment

Possible links between maternal periodontitis and adverse pregnancy outcome have been proposed, and appear to be supported by experimental models based on data from animal studies, in vitro work and human obstetric studies. This paper aims to review the current literature on human clinical investigations into such a relationship, based on current knowledge and in light of proposed mechanisms.

Keywords: periodontitis, pregnancy, complications, periodontal treatment, epidemiology

Desquamative gingivitis is a fairly common disorder, with a wide range of causes, most commonly lichen planus and mucous membrane pemphigoid. It may be the initial symptom of the underlying disorder, and patients may therefore present to the general dental practitioner or specialist in periodontology. The presence of plaque-induced gingival inflammation may exacerbate the condition, mask histological features of the underlying disorder, and can lead to delays in diagnosis and misdiagnosis. A definitive histological diagnosis should be made to ensure optimal management. Direct and indirect immunofluorescence tests help to achieve a diagnosis. In cases where a hypersensitivity reaction is suspected, skin patch-testing may help identify allergens. Management of oral symptoms includes removal of contributing/ causative factors where possible and medication with topical or systemic immunosuppressants.

Keywords: desquamative gingivitis, lichen planus, pemphigoid, pemphigus, hypersensitivity, lupus erythematosus, plasma cell gingivitis, dermatitis herpetiformis, linear IgA disease, orofacial granulomatosis

Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive condition characterised by palmoplantar keratoderma and severe prepubertal periodontitis. Increased susceptibility to both pyogenic skin infections and liver abscesses have been reported in a minority of cases. Haim- Munk syndrome, reported in only two families worldwide, shows a constellation of periodontitis, keratoderma, skin infections, arachnodactyly, acro-osteolysis and onychogryphosis. Allelic mutations in the Cathepsin C ( CTSC) gene are reported in PLS and HMS. We report a boy presenting with recurrent staphylococcal abscesses at four months of age. Prepubertal periodontitis was noted at two years nine months, with additional thickening and cracking of his palms and soles. His father and two paternal aunts are similarly affected, his father being edentulous since the age of 18. Mutation analysis in the CTSC gene confirmed a homozygous R272P mutation in the proband and his father, his mother being heterozygous. The periodontal management strategy has aimed to eliminate periodontal pathogens from the child and parents using non-surgical periodontal therapy and adjunctive systemic antibiotics. The skin has been treated with emollients and topical antiseptics. Our patient has features of PLS and highlights the susceptibility to skin infections as an important presenting sign. The R272P mutation has been previously noted in families with PLS without documented skin infections, suggesting either phenotypic heterogeneity or under-reporting/lack of awareness of this feature. Tendency to skin infections has been reported in both PLS and HMS, whereas acro-osteolysis, arachnodactyly and pes planus appear unique to the two families with reported HMS. PLS and HMS may represent opposite ends of a phenotypic spectrum of allelic CTSC mutations, with factors including polymorphisms in disease-modifying loci and environmental influences underpinning the heterogeneity. However, given the previously reported co-inheritance of PLS with albinism, it is also possible that HMS is a variant of PLS, arising following co-inheritance of a further, yet to be identified gene mutation in the vicinity of the CTSC gene locus.

Keywords: cathepsin C, Haim-Munk, keratoderma, Papillon-Lefèvre, pre-pubertal periodontitis, pyogenic skin infections

This report describes a case of carcinoma cuniculatum that presented initially as keratosis and ulceration of the gingiva when the patient attended for extraction of a persistently painful tooth in the right mandible. A series of mucosal biopsies and subsequent reviews showed hyperkeratosis associated with chronic candidosis and mild dysplasia but no evidence of neoplasia. However, vague symptoms of pain persisted in the mandible over a six-year period when the clinical signs were then consistent with osteomyelitis. A later biopsy included bone and indicated a diagnosis of carcinoma cuniculatum, a tumour that only rarely presents in the mouth. This necessitated radical excision of bone and grafting. Gingival lesions that initially appear innocuous may have the potential for malignant change. Biopsies of what might appear to be pre-malignant lesions usually ensure that invasive pathology is detected early. In this instance, however, the nature of the lesion meant that the carcinoma cuniculatum was only diagnosed following the more radical biopsy of bone.

Keywords: carcinoma, papillary, verrucous, mandibular neoplasia

This report describes the investigation, diagnosis and management of multiple pyogenic granulomata of the maxillary and mandibular gingivae in a nine-year-old boy. The child presented with a history of spontaneous gingival haemorrhage, gastro-intestinal disturbance and a limp involving his left leg. Investigations revealed a neglected child with the unique oral presentation of multiple pyogenic granulomata and syringomyelia involving the spinal chord between the 5th and 8th thoracic vertebra, with a consequent motor function deficit that led to the development of a spastic diplegic gate. Joint management with paediatric neurology improved both oral and spinal lesions, but despite arriving at a definitive diagnosis of "disseminated pyogenic granuloma" of the oral cavity, the spinal lesion appeared avascular and was deemed likely to be un-related. The oral lesions were therefore definitively diagnosed and managed as multiple pyogenic granuloma's rather than disseminated lesions. This report focuses on multiple and disseminated pyogenic granulomata and syringomyelia as medical conditions, their management and the importance of collaborative care pathways between periodontal and neurological physicians in successful management.

Keywords: multiple pyogenic granulomata, disseminated pyogenic granulomata, syringomyelia, spontaneous gingival haemorrhage

This report describes the appearance and management of an oral squamous cell carcinoma (SCC), which arose within an area of gingival lichen planus in an 80-year old female patient. The patient was under regular recall to monitor an area of desquamative gingivitis, the underlying cause for which was gingival lichen planus. In this paper we describe the rapid appearance of a superficial spreading invasive SCC, the investigations performed and the clinical course and management of the tumour. This paper also discusses the possibility that utilisation of topical oral steroids in the symptomatic management of erosive or atrophic oral lesions, may play a role in the initiation or progression of the malignancy.

Keywords: gingival lichen planus, gingival squamous cell carcinoma, topical steroid therapy

A 13-year-old girl was referred by her orthodontist for pre-orthodontic management of her gingival condition that, despite the implementation of appropriate and targeted oral hygiene measures, had not improved and was inconsistent with her level of plaque control. We shall call her by a pseudo name, "Jane".

Keywords: self-inflicted trauma, factitious injury, psychosocial, behavioural analysis