A review and proposal for the etiology of acute necrotizing gingivitis

Acute periodontal lesions

This review provides updates on acute conditions affecting the periodontal tissues, including abscesses in the periodontium, necrotizing periodontal diseases and other acute conditions that cause gingival lesions with acute presentation, such as infectious processes not associated with oral bacterial biofilms, mucocutaneous disorders and traumatic and allergic lesions. A periodontal abscess is clinically important because it is a relatively frequent dental emergency, it can compromise the periodontal prognosis of the affected tooth and bacteria within the abscess can spread and cause infections in other body sites. Different types of abscesses have been identified, mainly classified by their etiology, and there are clear differences between those affecting a pre-existing periodontal pocket and those affecting healthy sites. Therapy for this acute condition consists of drainage and tissue debridement, while an evaluation of the need for systemic antimicrobial therapy will be made for each case, based on local and systemic factors. The definitive treatment of the pre-existing condition should be accomplished after the acute phase is controlled. Necrotizing periodontal diseases present three typical clinical features: papilla necrosis, gingival bleeding and pain. Although the prevalence of these diseases is not high, their importance is clear because they represent the most severe conditions associated with the dental biofilm, with very rapid tissue destruction. In addition to bacteria, the etiology of necrotizing periodontal disease includes numerous factors that alter the host response and predispose to these diseases, namely HIV infection, malnutrition, stress or tobacco smoking. The treatment consists of superficial debridement, careful mechanical oral hygiene, rinsing with chlorhexidine and daily re-evaluation. Systemic antimicrobials may be used adjunctively in severe cases or in nonresponding conditions, being the first option metronidazole. Once the acute disease is under control, definitive treatment should be provided, including appropriate therapy for the pre-existing gingivitis or periodontitis. Among other acute conditions affecting the periodontal tissues, but not caused by the microorganisms present in oral biofilms, infectious diseases, mucocutaneous diseases and traumatic or allergic lesions can be listed. In most cases, the gingival involvement is not severe; however, these conditions are common and may prompt an emergency dental visit. These conditions may have the appearance of an erythematous lesion, which is sometimes erosive. Erosive lesions may be the direct result of trauma or a consequence of the breaking of vesicles and bullae. A proper differential diagnosis is important for adequate management of the case.

NOMA: A Preventable "Scourge" of African Children

Noma is a serious orofacial gangrene originating intraorally in the gingival-oral mucosa complex before spreading extraorally to produce a visibly destructive ulcer. Although cases of noma are now rarely reported in the developed countries, it is still prevalent among children in third world countries, notably in sub-Sahara Africa, where poverty, ignorance, malnutrition, and preventable childhood infections are still common. This review summarizes historical, epidemiological, management, and research updates on noma with suggestions for its prevention and ultimate global eradication. The global annual incidence remains high at about 140,000 cases, with a mortality rate exceeding 90% for untreated diseases. Where the patients survive, noma defects result in unsightly facial disfigurement, intense scarring, trismus, oral incompetence, and social alienation. Although the etiology has long been held to be infectious, a definitive causal role between microorganisms cited, and noma has been difficult to establish. The management of noma with active disease requires antibiotics followed by reconstructive surgery. Current research efforts are focused towards a comprehensive understanding of the epidemiology, and further elucidation of the microbiology and pathogenesis of noma.Although a formidable public health challenge, noma can be prevented with a potential for subsequent global eradication. To achieve both desirable goals, detection of early disease is crucial because these early lesions respond to conventional antibiotic treatments when instituted side by side with nutritional rehabilitation, and obviates the necessity for extensive surgical reconstruction often indicated in late stage disease. The eradication of noma in the developed world in the mid 20(th) century bears out the notion of a similar outcome following effective preventive strategies in Africa. A fundamental and necessary step towards attaining this goal is for the international community to adopt a perception of noma as an urgent global public health challenge. Research effort toward deciphering the microbiology, molecular events, and pathogenesis of noma also should intensify.

An oro-facial disease 'noma (cancrum oris)' in a Japanese monkey (Macaca fuscata): clinical signs, clinicopathological features, and response to treatment

BACKGROUND

A Japanese monkey developed severe oro-facial lesions that were called noma in humans. Although extensive destruction of both the buccal regions occurred with rapid progress, author successfully treated the lesions with povidone-iodine, enrofloxacin, chymotrypsin, a glycyrrhizin preparation, and a basic fibroblast growth factor.

METHODS

Author clinicopathologically investigated this disease during the treatment.

RESULTS

In the subcutaneous and muscular tissues, the lesions developed characteristic changes such as dissolving collagen fibers and muscular tissues phagocytosed by giant and epitheloid cells. The monkey showed a notable increase in creatine kinase activities. The present examinations revealed severe invasive findings in muscular tissues, which were accompanied by infections of beta-hemolytic streptococcus Group C. This monkey was negative for simian immunodeficiency virus antibody; however, infection with simian D retrovirus was not ruled out.

CONCLUSIONS

Simian noma was a rapidly devastating disease, which destroyed the muscle tissues of oro-facial structure. Nonhuman primates are the only species that develop oro-facial lesions, corresponding to noma in humans.

Noma (cancrum oris)

Noma is an opportunistic infection promoted by extreme poverty. It evolves rapidly from a gingival inflammation to grotesque orofacial gangrene. It occurs worldwide, but is most common in sub-Saharan Africa. The peak incidence of acute noma is at ages 1-4 years, coinciding with the period of linear growth retardation in deprived children. Noma is a scourge in communities with poor environmental sanitation. It results from complex interactions between malnutrition, infections, and compromised immunity. Diseases that commonly precede noma include measles, malaria, severe diarrhoea, and necrotising ulcerative gingivitis. The acute stage responds readily to antibiotic treatment. The sequelae after healing include variable functional and aesthetic impairments, which require reconstructive surgery. Noma can be prevented through promotion of national awareness of the disease, poverty reduction, improved nutrition, promotion of exclusive breastfeeding in the first 3-6 months of life, optimum prenatal care, and timely immunisations against the common childhood diseases.

Noma: an "infectious" disease of unknown aetiology

Noma (cancrum oris) is a devastating gangrenous disease that leads to severe tissue destruction in the face and is associated with high morbidity and mortality. It is seen almost exclusively in young children living in remote areas of less developed countries, particularly in Africa. The exact prevalence of the disease is unknown, but a conservative estimate is that 770000 people are currently affected by noma sequelae. The cause remains unknown, but a combination of several elements of a plausible aetiology has been identified: malnutrition, a compromised immune system, poor oral hygiene and a lesion of the gingival mucosal barrier, and an unidentified bacterial factor acting as a trigger for the disease. This review discusses the epidemiology, clinical features, current understanding of the pathophysiology, and treatment of the acute phase and sequelae requiring reconstructive surgery. Noma may be preventable if recognised at an early stage. Further research is needed to identify more exactly the causative agents.

Detection of human viruses in patients with chronic periodontitis and the relationship between viruses and clinical parameters

BACKGROUND

Recent studies have demonstrated that various human viruses, especially cytomegalovirus (HCMV), Epstein-Barr virus type-1 (EBV-1), and herpes simplex virus (HSV), seem to play a part in the pathogenesis of human periodontitis. Little information is available on the relationship between these viruses and clinical periodontal parameters in patients with chronic periodontitis. This study examined the occurrence of HCMV, EBV-1, and HSV in patients with chronic periodontitis and the relationship between these viruses and clinical parameters.

METHODS

A nested polymerase chain reaction (PCR) method determined the presence of HCMV, EBV-1, and HSV. Subgingival plaque samples from 30 patients with chronic periodontitis and 21 randomly selected healthy controls were collected by paper points, and clinical measurements were recorded from both sampling sites and entire dentition. The following indices were measured: plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (CAL).

RESULTS

HCMV was detected in 44.3% of chronic periodontitis patients and 14.3% of healthy persons (P < 0.05); EBV-1 in 16.7% of chronic periodontitis patients and 14.3% of healthy persons (P = 1.00); and HSV in 6.7% of chronic periodontitis patients and in no healthy persons. HCMV and EBV-1 detected and undetected sites in patients with periodontitis showed statistically significant differences in sampling clinical depth (SPD) and sampling clinical attachment loss (SCAL). Differences in the measurements of PI of entire dentition and GI of entire dentition between HSV detected and undetected sites were statistically significant.

CONCLUSIONS

Findings of the present study confirm the frequent presence of HCMV in crevicular samples of chronic periodontitis lesions, and suggest a strong relationship between the presence of HCMV and EBV-1 in subgingival areas and the measurements of probing depth and probing attachment loss.

Cytomegalovirus and cyclosporin-induced gingival overgrowth in children with liver grafts

OBJECTIVE

To determine whether cytomegalovirus (CMV) is associated with gingival overgrowth in paediatric liver graft recipients treated with cyclosporin.

STUDY DESIGN

Thirty-four children, 25 of whom were under 5 years of age, who had undergone liver transplantation, were examined. An Index of Severity of Gingival Overgrowth was used to measure the prevalence and severity of the gingival overgrowth. The trough cyclosporin level was recorded and the CMV status of the patient matched to the dental findings. The association between the severity of gingival overgrowth and CMV infection was examined using the contingency coefficient. An anova was used to assess the association between the circulating trough cyclosporin concentration and the severity of gingival overgrowth. Pearson's Product Moment Correlation Coefficient was used to examine the association between the duration of exposure to cyclosporin and the severity of gingival overgrowth.

RESULTS

There was a significant inverse association between the duration of exposure to cyclosporin and the severity of gingival overgrowth. There was no relationship between the trough cyclosporin concentration and the severity of gingival overgrowth. There was no association between CMV and gingival overgrowth.

CONCLUSION

Gingival overgrowth was related to the duration of cyclosporin therapy but was neither more prevalent nor more severe in subjects who were CMV seropositive.

Oro-facial gangrene (noma/cancrum oris): pathogenetic mechanisms

Cancrum oris (Noma) is a devastating infectious disease which destroys the soft and hard tissues of the oral and para-oral structures. The dehumanizing oro-facial gangrenous lesion affects predominantly children ages 2 to 16 years, particularly in sub-Saharan Africa, where the estimated frequency in some communities varies from 1 to 7 cases per 1000 population. The risk factors are poverty, malnutrition, poor oral hygiene, residential proximity to livestock in unsanitary environments, and infectious diseases, particularly measles and those due to the herpesviridae. Infections and malnutrition impair the immune system, and this is the common denominator for the occurrence of noma. Acute necrotizing gingivitis (ANG) and oral herpetic ulcers are considered the antecedent lesions, and ongoing studies suggest that the rapid progression of these precursor lesions to noma requires infection by a consortium of micro-organisms, with Fusobacterium necrophorum (Fn) and Prevotella intermedia (Pi) as the suspected key players. Additional to production of a growth-stimulating factor for Pi, Fn displays a classic endotoxin, a dermonecrotic toxin, a cytoplasmic toxin, and a hemolysin. Without appropriate treatment, the mortality rate from noma is 70-90%. Survivors suffer the two-fold afflictions of oro-facial mutilation and functional impairment, which require a time-consuming, financially prohibitive surgical reconstruction.

Classifications of oral lesions in HIV infection

BACKGROUND

Manifestations of immunosuppression may take the form of opportunistic infection, and neoplasia. While this paper has focused on gingival and periodontal manifestations. these tissues cannot be evaluated in isolation. The presence of involvement of other oral tissues such as the cheek or tongue with manifestations associated with HIV such as hairy leukoplakia, Kaposi's sarcoma at these sites, and candidiasis in addition to periodontal manifestations may further increase the clincal suspicion of underlying immunosuppression and/or progression of the immunosuppressive state.

DISCUSSION

The periodontist plays an essential r le in identifying the periodontal status of an individual and has an important r le to play in early recognition of signs and symptoms of HIV disease or progression of the medical condition.

CONCLUSION

Only through such recognition can appropriate definitive diagnostic testing be conducted, and appropriate therapeutic intervention for the oral condition and the systemic condition be considered.

Noma (cancrum oris): questions and answers

Noma (cancrum oris) is an infectious disease which destroys the oro-facial tissues and other neighboring structures in its fulminating course. It affects predominantly children aged 2-16 years in sub-Saharan Africa where the estimated frequency in some communities may vary from one to seven cases per 1000 children. The key risk factors are poverty, malnutrition, poor oral hygiene, deplorable environmental sanitation, close residential proximity to livestock, and infectious diseases, particularly measles. Malnutrition acts synergistically with endemic infections in promoting an immunodeficient state, and noma results from the interaction of general and local factors with a weakened immune system as the common denominator. Acute necrotizing gingivitis (ANG) is considered the antecedent lesion. Current studies suggest that evolution of ANG to noma requires infection by a consortium of microorganisms with Fusobacterium necrophorum and Prevotella intermedia as the suspected key players. Without appropriate treatment, mortality rate is 70-90%. Survivors suffer the two-fold affliction of oro-facial disfigurement and functional impairment. Reconstructive surgery of the resulting deformity is time-consuming and financially prohibitive for the victims who are poor.

Living conditions of children at risk for noma: Nigerian experience

The study reported in this paper was carried out in the Northwestern and Southwestern regions of Nigeria, between October 1996 and April 1998. The study examined the possible contributory role of living conditions in the development of acute necrotizing gingivitis (ANG) or noma from oral lesions. Questionnaire data obtained from 42 fresh noma cases seen in the Northwest and four fresh cases seen in the Southwest were examined. In addition 46 cases of advanced ANG from the Southwest were included. The main focus was to compare some of the environmental living conditions of cases with advanced ANG and those with noma in these regions. All the noma and ANG cases were seen in children aged 2-12 years. The level of good oral hygiene practices and general environmental living conditions were significantly higher in the Southwest than in the Northwest. Data also showed that living in close proximity with livestock was significantly higher in the Northwest than in the Southwest (P < 0.05). The environmental living conditions of children in the Northwest were further compounded by poor sanitary faecal disposal practices as well as minimal access to potable water. The overall data indicated that living in substandard accommodations, exposure to debilitating childhood diseases, living in close proximity to livestock, poor oral hygiene, limited access to potable water and poor sanitary disposal of human and animal faecal waste could have put the children in the Northwest at higher risk for noma than the children in the Southwest. These could have been responsible for the higher prevalence of noma in the Northwest than in the Southwest.

Human Herpesviridae in acute necrotizing ulcerative gingivitis in children in Nigeria

Herpesviruses have been implicated in the pathogenesis of human periodontitis. The present study investigated whether herpesviruses are present in the lesions of acute necrotizing ulcerative gingivitis. Sixty-two Nigerian children, aged 3-14 years, were studied. Twenty-two children had acute necrotizing ulcerative gingivitis and were also malnourished, 20 exhibited no acute necrotizing ulcerative gingivitis but were malnourished and 20 were free of acute necrotizing ulcerative gingivitis and in a good nutritional state. Polymerase chain reaction methods were used to determine the presence of human cytomegalovirus (HCMV), Epstein-Barr virus type 1 and type 2 (EBV-1, EBV-2), herpes simplex virus (HSV), human herpes virus 6 (HHV-6), human papilloma virus and human immunodeficiency virus type 1 in crevicular fluid specimens collected by paper points. Of the 22 acute necrotizing ulcerative gingivitis patients, 15 (68%) revealed viral infection and 8 (36%) viral coinfection. Thirteen (59%) acute necrotizing ulcerative gingivitis patients demonstrated HCMV, 6 (27%) EBV-1, 5 (23%) HSV and 1 (5%) HHV-6. Only 2 (10%) subjects from each group not affected by acute necrotizing ulcerative gingivitis showed viral presence, and no control subject revealed viral coinfection. These findings suggest that HCMV and possibly other herpesviruses contribute to the onset and/or progression of acute necrotizing ulcerative gingivitis in malnourished Nigerian children.

Detection of human viruses in periodontal pockets using polymerase chain reaction

Even though viruses have been implicated in the etiology of several medical and dental disorders, little or no data are available on the possible involvement of human viruses in the pathogenesis of human periodontal disease. This study investigated the presence of human cytomegalovirus, Epstein-Barr virus, herpes simplex virus, human papillomavirus and human immunodeficiency virus (HIV) in crevicular fluid samples from 30 patients with advanced periodontitis and 26 subjects with gingivitis. Viral identification was performed on direct subgingival samples from 3 diseased sites in each patient using the polymerase chain reaction technique. Seventy-eight percent of advanced periodontitis patients were positive for at least one of the five test viruses. Cytomegalovirus was detected in 60% of the periodontitis patients, Epstein-Barr virus in 30%, herpes simplex virus in 20%, human papillomavirus in 17% and HIV in 7%. Forty percent of the periodontitis patients revealed coinfection by 2 to 5 viruses. Only 31% of the gingivitis subjects showed a positive viral identification in crevicular fluid, and infected individuals only revealed human cytomegalovirus. This study demonstrated that human viruses may occur in periodontitis lesions with relatively high prevalence. The pathogenetic significance of human viruses in destructive periodontal disease needs to be determined.

Periodontal diseases in HIV-infected patients

Periodontal diseases may be the first clinical sign of human immunodeficiency virus (HIV)-infection. Since the immunosuppression and subsequent susceptibility may alter the responses of the oral tissues as well as the microflora, both periodontal treatment and result of therapy may be modified. The periodontal diseases in HIV-seropositive patients include common as well as less conventional forms of gingivitis and periodontitis, and bacterial, mycotic and viral infections are seen. Neoplasias may also involve the periodontium; most common are Kaposi's sarcoma and non-Hodgkin's lymphoma. Recent studies of unselected groups of patients indicate that periodontal health in at least some groups of HIV-seropositive patients is better than previously reported.

Cytomegalovirus: a virus of increasing relevance to oral medicine and pathology

Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus, emerging as an opportunistic pathogen in immunocompromised persons, particularly those infected with human immunodeficiency viruses (HIV). Clinical syndromes caused by HCMV are usually not specifically identifiable without laboratory investigations. However, it is now apparent that HCMV may cause oral ulceration in immunocompromised persons and it may play a role in other diverse conditions in these and other patients.

Oral manifestations of cytomegalovirus infection

Disease caused by cytomegalovirus is reported with increasing frequency. Cytomegalovirus is an important pathogen in immunocompromised and immunosuppressed patients. The most common manifestation of cytomegalovirus infection of the gastrointestinal tract including the oral mucosa is ulceration. The role of cytomegalovirus in xerostomia, Sjögren's syndrome, and Kaposi's sarcoma is continuing to be investigated. This article reviews the oral manifestations of cytomegalovirus, including recently reported oral manifestations.

The impact of tobacco use and cessation on oral and dental diseases and conditions

Smoked and smokeless tobacco use produces profound effects on soft and hard tissues in and around the oral cavity. Because many of these changes are clinically observable, dentists, oral hygienists, and related health professionals are in ideal positions to give patients specific information concerning the oral ill effects of tobacco use. This article links tobacco use with a wide range of malignant, precancerous, and nonmalignant changes in the oral and perioral environment and addresses the documented benefits of quitting. Oral conditions less definitively linked to tobacco are also discussed.

Detection of high-risk groups and individuals for periodontal diseases: laboratory markers based on the microbiological analysis of subgingival plaque

Periodontal microbiology is reviewed with regard to the potential of certain characteristics to serve as markers of high risk groups or individuals for periodontal diseases. The generally accepted associations between particular organisms and the various periodontal diseases are discussed. The usefulness of various clinical study designs is reviewed. The ecology of the subgingival plaque microflora is discussed and a number of suggestions for future research are made. We have concluded that there is no monospecific aetiology to any of the various periodontal conditions. Nevertheless, we give particular attention to the role of the black-pigmented bacteroides based upon our belief that they, and Bacteroides gingivalis in particular, are fundamental to our understanding of the biology of periodontal diseases in humans and other animals. Consequently, the contribution of its various virulence factors and their potential as markers of disease susceptibility and activity is addressed.

Antibody testing and counseling of dental patients at risk for human immunodeficiency virus (HIV) infection and associated clinical findings

Two hundred six dental patients were tested between 1985 and 1987 for antibodies to human immunodeficiency virus (HIV) when a review of their medical histories revealed a high risk for infection. Serologic results are correlated with soft tissue and osseous findings recorded during routine head and neck and radiographic examination. Counseling recommendations for use in association with testing are outlined. A more active role for the dentist as a preventive agent is advocated to combat the spread of acquired immunodeficiency syndrome (AIDS).

Detection of high-risk groups and individuals for periodontal diseases. Evidence for the existence of high-risk groups and individuals and approaches to their detection

It is argued that the periodontal diseases can no longer be regarded as universally prevalent conditions to which all members of the world's population are at equal risk if they fail to practise good oral hygiene. Rather, they should be regarded as a range of different diseases for each of which certain individuals, which together comprise certain minority groups, are at relatively high risk. The epidemiological evidence for the existence of high-risk groups is reviewed, from which it is concluded that world-wide the prevalence of severe destructive periodontitis is of the order of only 7-15% of the adult dentate population. A working classification of the different types of gingivitis and periodontitis is offered, as is a summary of the theoretically possible approaches to the detection of high-risk groups and individuals which are explored in detail in subsequent papers. Successful identification of such individuals will permit scientifically valid, rational and targetted prevention and treatment.