Herpesviruses in periodontal pocket and gingival tissue specimens

Correlation between different genotypes of human cytomegalovirus and Epstein-Barr virus and peri-implant tissue status

BACKGROUND

The purpose of this study was to estimate the prevalence of different genotypes of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in peri-implantitis and mucositis sites, and to evaluate the correlation between herpesvirus presence and clinical parameters.

METHODS

A total of 80 dental implants (mean time of loading, 4.16 ± 1.8 years) were evaluated during the course of the study (30 peri-implantitis, 25 mucositis and 25 healthy peri-implant sites). The following clinical parameters were assessed: visible plaque index, bleeding on probing, suppuration and probing depth. A polymerase chain reaction (PCR) assay was used to identify the presence of different HCMV and EBV genotypes in peri-implant tissue plaque samples.

RESULTS

HCMV-2 was detected in 53.3% and EBV-1 in 46.6% of the 30 peri-implantitis sites evaluated. By contrast, HCMV-2 was not detected in healthy periodontal sites and EBV-1 was detected in one healthy site. A statistically significant correlation was found between the presence of HCMV-2 and EBV-1 genotypes and clinical parameters of peri-implantitis.

CONCLUSIONS

The results from the present study confirmed the high prevalence of HCMV-2 and EBV-1 in the peri-implant tissue plaque of peri-implantitis sites and suggests a possible active pathogenic role of the viruses in peri-implantitis.

Correlation of cytomegalovirus and human herpesvirus 7 with CD3+ and CD3+ CD4+ cells in chronic periodontitis patients

BACKGROUND AND OBJECTIVE

Human chronic periodontitis is an inflammatory process characterized by dense accumulation of immune cells in the periodontal tissue. The periodontitis can lead to loss of teeth in the patient and the pathogenesis of this disease is not completely known. This study tested the hypothesis that chronic periodontitis-affected sites can harbor betaherpesviruses and that viruses are linked to a profile of the inflammatory infiltrate.

MATERIAL AND METHODS

Biopsies of periodontal tissue were taken from periodontitis-affected patients and from healthy subjects. Immunohistochemistry was performed to count CD19(+) B cells, CD3(+) total T cells, T-CD4(+) and T-CD8(+) cell subsets, and PCR was performed to detect cytomegalovirus and human herpesvirus 6 and 7 in the samples. One slide of each sample was stained with Giemsa for histopathological examination and to evaluate the quality of the cellular infiltrate.

RESULTS

As expected, tissues collected from healthy subjects presented no significant level of inflammatory infiltration and were therefore excluded from immunostaining procedures. Results showed that CD19(+) B cells were in higher number than CD3(+) T cells in the periodontitis-affected tissue, but this was not statistically significant. The T-CD4(+) lymphocyte subset was significantly higher than the T-CD8(+) lymphocyte subset (p = 0.004) in the samples. Cytomegalovirus and human herpesvirus 7 were found at periodontitis-affected sites, but not in tissue collected from healthy subjects (p = 0.04 and p = 0.04, respectively). Human herpesvirus 6 was rarely detected. We found a correlation between cytomegalovirus and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and between human herpesvirus 7 and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and higher CD4(+) /CD8(+) ratios (ratio > 1.1, p = 0.002).

CONCLUSION

This study shows that cytomegalovirus and human herpesvirus 7 can be present at periodontitis-affected sites but are uncommon at healthy periodontal sites. Moreover, our data suggest that cytomegalovirus can be related to an inflammatory infiltrate with predominance of CD3(+) T cells, whereas human herpesvirus 7 can be associated with an infiltrate with predominance of T-CD4(+) cells. However, further studies are necessary to support this hypothesis. Herpesviruses could play a role in human chronic periodontitis by modulation of the T cell response.

Identification of herpesviruses types 1 to 8 and human papillomavirus in acute apical abscesses

INTRODUCTION

It has been suggested that viruses, especially herpesviruses, can play a role in the pathogenesis of marginal and apical periodontitis. This study aimed to detect herpesviruses types 1 to 8, namely herpes simplex virus (HSV-1/2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus-6 (HHV-6), human herpesvirus-7 (HHV-7), and human herpesvirus-8 (HHV-8) as well as human papillomavirus (HPV) in acute apical abscesses.

METHODS

Twenty-four samples were taken by aspiration of the purulent exudate from acute apical abscesses. DNA extracted from clinical samples served as a template in single or nested polymerase chain reaction (PCR) assays for the detection of the target viruses.

RESULTS

Control PCR reactions with β-globin gene primers revealed that all samples but one had detectable human DNA. Of the 23 abscess samples positive for the β-globin gene, 14 (61%) were positive for at least one of the target human viruses. Thirteen (56.5%) cases had herpesvirus: HHV-8 occurred in 11 (48%), VZV and HHV-6B in two (9%), and HHV-7 and HSV-1/2 in one (4%). EBV and HCMV were not present in any of the examined samples. HPV was detected in three (13%) abscess samples. Viral coinfection was found in five cases, with one case harboring three of the targeted viruses.

CONCLUSION

A large number of abscess samples were positive for at least one target virus. Unexpectedly, HHV-8 was for the first time detected and in a high prevalence. Papillomavirus and other herpesviruses were also found for the first time in endodontic abscesses. Although these findings suggest an association, the specific role of viruses in the pathogenesis of acute apical abscesses awaits further clarification.

Human papillomavirus-16 prevalence in gingival tissue and its association with periodontal destruction: a case-control study

BACKGROUND

Human papillomavirus (HPV)-16 is detected in normal oral mucosa and several oral lesions, including squamous cell carcinoma, condyloma acuminatum, verruca vulgaris, focal epithelial hyperplasia, and periodontal diseases. It was hypothesized that HPV may be involved in periodontal breakdown and that periodontal tissue acts as a reservoir for the virus. Therefore, in this study, the prevalence of HPV-16 in the gingival tissue of Brazilians with periodontal health or disease is investigated.

METHODS

Fifty-six gingival samples from subjects with chronic periodontitis, 26 samples from subjects with gingivitis, and 22 samples from subjects with healthy peridontium were analyzed. Total DNA was extracted, and the presence of HPV-16 was assessed using a real-time polymerase chain reaction. Positive and negative controls were included in the reactions.

RESULTS

HPV-16 was not detected in any of the 104 gingival samples evaluated; therefore, this virus showed no association with periodontal disease in this study.

CONCLUSION

In the population studied, HPV-16 may not have participated in the pathogenesis of chronic periodontitis, and the gingival tissue did not act as a reservoir for this virus.

Detection of herpetic viruses in gingival crevicular fluid of patients suffering from periodontal diseases: prevalence and effect of treatment

BACKGROUND/AIM

Although the role of bacteria in the etiology of periodontitis is well established, it has been suggested that herpetic viruses could contribute to the initiation and progression of this disease. The aim of this study was to determine the prevalence of human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) and herpes simplex virus (HSV) in gingival crevicular fluid (GCF) samples obtained from periodontally healthy, gingivitis and periodontitis patients. In addition, the effect of periodontal treatment (scaling and root planing) on the persistence of herpetic viruses was evaluated in a sub-group of patients suffering from chronic periodontitis.

METHODS

The presence of viruses in GCF samples was assessed by a nested PCR amplification technique. The persistence of viruses in periodontal sites was evaluated following a scaling and root planing therapy.

RESULTS

A statistically significant higher prevalence of HCMV was observed in periodontitis patients as compared to healthy control subjects (35 vs. 8%, respectively; P = 0.0377). A trend for a higher prevalence of HSV was also noted in the periodontitis group, in comparison with healthy control subjects. In addition, a higher prevalence of HCMV was associated with deep periodontal pockets in subjects suffering from periodontitis. In the sub-group of periodontitis patients, periodontal therapy resulted in the elimination (HCMV and EBV) or reduction (HSV) of the herpetic viruses.

CONCLUSIONS

This study showed that the prevalence of HCMV and HSV viruses in GCF is higher in patients suffering from periodontitis compared to periodontally healthy subjects, and that the prevalence of HCMV is higher in deep periodontal pockets. It also brought evidences that periodontal therapy may be associated with virus elimination in diseased sites.

EBV and CMV in chronic periodontitis: a prevalence study

Periodontitis is an infectious disease involving specific bacteria and viruses. Herpesviruses believed to play roles in it. The present study examines the presence of Epstein-Barr virus (EBV) and cytomegalovirus (CMV) in subgingival and supragingival plaque of 61 patients with chronic periodontitis and 40 healthy controls. A nested polymerase chain reaction method was used. The clinical parameters, clinical attachment level (CAL), probing depth (PD) and bleeding on probing (BOP) were examined. Prevalence of EBV- 1, EBV-2 and CMV were 73.8%, 4.9% and 59%; respectively. There was no association between the presence of EBV-1, EBV-2 and CMV with bleeding on depth.

Prevalence of Epstein-Barr virus type 1 in patients with chronic periodontitis by nested-PCR

The present study evaluated the subgingival presence of Epstein-Barr virus type 1 (EBV-1) in patients with chronic periodontitis with nested-PCR. Subgingival plaque samples from 61 patients with chronic periodontitis with Probing Depth (PD) > or = 6 and 40 healthy controls were collected by sterile curette. DNA was extracted. A nested Polymerase Chain Reaction (PCR) method determined presence of EBV-1. The study included 61 patients (34 women, 27 men; 24-69 years of age; mean 43) and 40 periodontally health controls (22 Women, 18 men, 21-69 years in age; mean 41.35%). EBV type 1 was detected in 37 samples (60.7%) and 1 samples (2.5%) of chronic periodontitis patients and healthy subjects, respectively. This study demonstrated that EBV-1 infection is associated with the activity of chronic periodontitis.

EBV-1 and HCMV in aggressive periodontitis in Brazilian patients

The purpose of the present investigation was to compare the presence of Epstein-Barr virus type 1 (EBV-1) and of Human Cytomegalovirus (HCMV) in crevicular fluid samples from deep and shallow periodontal pocket sites of Brazilian patients with aggressive periodontitis. A total of 30 systemically healthy patients with aggressive periodontitis participated in the study. Paper points were inserted into 2 gingivitis sites (< 3 mm) and into 2 periodontitis sites (> 5 mm) in each patient. PCR assay was used to identify genomic copies of HCMV and EBV-1. Twenty-three patients (77%) were positive for EBV-1, while only 2 patients (6%) were positive for HCMV. The McNemar test revealed a positive association between EBV-1 and periodontal lesions (p = 0.043). Thirty-four (57%) out of 60 periodontitis sites were positive for EBV-1, whereas 18 (30%) gingivitis sites were positive (p = 0.01). Only two sites (6.7%) were positive for HCMV. No positive association was found between HCMV and periodontitis or gingivitis (p = 0.479). The elevated occurrence of EBV-1 DNA in periodontal pockets of patients with aggressive periodontitis supports a possible periodontopathic role of this virus.

Correlation between infections with different genotypes of human cytomegalovirus and Epstein-Barr virus in subgingival samples and periodontal status of patients

Accumulating evidence indicates that herpesviruses may be putative pathogens in various types of periodontal diseases. The present study was performed to examine infections with different genotypes of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in subgingival samples from a Chinese population and to analyze the correlation with periodontal status. A nested PCR assay was used to identify the presence of HCMV, EBV type 1 (EBV-1), and EBV-2; and the amplicons were further analyzed by restriction fragment length polymorphism analysis. HCMV was detected in 79.0% of 143 chronic periodontitis (CP) patients, 78.5% of 65 gingivitis patients, and 76.3% of 76 periodontally healthy individuals, while EBV was found in 63.6%, 32.3%, and 30.3% of the three groups of subjects, respectively. The HCMV-positive PCR products from all the samples were identified as corresponding to gB genotype I (gB-I) or gB-II. HCMV gB-II (62.9%), EBV-1 (43.4%), and EBV-2 (18.2%) were associated with CP at higher frequencies (P < 0.05), whereas HCMV gB-I was more often observed in gingivitis patients (40.0%) and healthy individuals (40.8%) (P < 0.05). Furthermore, a higher rate of coinfection with HCMV and EBV was shown in CP patients (52.4%), especially dual infections with HCMV gB-II and EBV-1 (30.8%) or HCMV gB-II and EBV-2 (12.6%), compared with the rates of single infections with HCMV or EBV (P < 0.05). Infection with HCMV gB-II, EBV-1, or EBV-2 was correlated with higher rates of bleeding on probing (P < 0.05). In patients infected with HCMV gB-II or both HCMV and EBV, including HCMV gB-II and EBV-1, a deeper probing depth or more serious attachment loss was found (P < 0.05). These findings clearly indicate that HCMV gB-II is the dominant genotype detected in subgingival samples in CP. HCMV gB-II infection and HCMV gB-II coinfection with EBV-1 are closely associated with periodontal tissue inflammation and destruction.

Interleukin 18 and periodontal disease

Cytokines are of major importance in periodontal disease progression. It is generally agreed that control of the Th1/Th2 balance is central to the immunoregulation of periodontal disease. There is increasing evidence in humans that the stable periodontal lesion is mediated by Th1 cells, while the progressive lesion sees a shift toward Th2 cells. Equally, there is conflicting evidence, mainly in animal models, that bone loss is mediated by Th1 responses, and that Th2 responses are protective. In the presence of IL-12, IL-18 induces Th1 responses while, in the absence of IL-12, it promotes Th2 responses. It is clear, therefore, that since IL-18 has the ability to induce either Th1 or Th2 differentiation, it becomes important to consider its role in periodontal disease. This review endeavors to give an overview of this cytokine and its relevance for periodontal disease.

Herpesviral-bacterial synergy in the pathogenesis of human periodontitis

PURPOSE OF REVIEW

Periodontitis is an infectious disease, but the specific mechanisms by which tooth-supportive tissues are lost remain obscure. This article proposes an infectious disease model for periodontitis in which herpesviral-bacterial interactions assume a major etiopathogenic role.

RECENT FINDINGS

Epstein-Barr virus type 1, cytomegalovirus and other herpesviruses occur at a high frequency in aggressive periodontitis lesions. Also, herpesvirus-infected periodontitis lesions tend to harbor elevated levels of classic periodontopathic bacteria, including Porphyromonas gingivalis, Dialister pneumosintes, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Treponema denticola and Actinobacillus (Aggregatibacter) actinomycetemcomitans.

SUMMARY

Conceivably, a herpesvirus active infection in the periodontium impairs local defenses, thereby permitting overgrowth and increased aggressiveness of periodontopathic bacteria. In turn, periodontal pathogenic bacteria may augment the virulence of periodontal herpesviruses. It is suggested that interactions among herpesviruses and specific bacterial species constitute an important pathogenetic feature of periodontitis and maybe also of various non-oral infections.

Infection frequency of Epstein-Barr virus in subgingival samples from patients with different periodontal status and its correlation with clinical parameters

OBJECTIVE

To detect the infection frequencies of different genotypes of Epstein-Barr virus (EBV) in subgingival samples from chronic periodontitis (CP) patients, and to discuss the correlation between infection with EBV and clinical parameters.

METHODS

Nested-PCR assay was used to detect EBV-1 and EBV-2 in subgingival samples from 65 CP patients, 65 gingivitis patients and 24 periodontally healthy individuals. The amplicons were further identified by restriction fragment length polymorphism analysis (RFLP) with endonucleases Afa I and Stu I. Clinical parameters mainly included bleeding on probing (BOP), probing depth (PD), attachment loss (AL) in six sites of the dentition.

RESULTS

In CP patients, gingivitis and periodontally healthy individuals, the infection frequencies were 47.7%, 24.6% and 16.7% for EBV-1, and 15.4%, 7.7% and 0% for EBV-2, respectively. In 2 out of the 65 CP patients co-infection of EBV-1 and EBV-2 was found. The positive rate of EBV-1 in chronic periodontitis patients was higher than that in gingivitis patients (P=0.01) and periodontally healthy individuals (P=0.01). But no significant difference was shown in EBV-1 frequency between gingivitis patients and healthy individuals (P>0.05) or in EBV-2 frequency among the three groups (P>0.05). In CP patients, higher mean BOP value was found in EBV-1 or EBV-2 positive patients than that in EBV negative ones (P<0.01), but with no statistical difference in the mean PD or AL value between EBV positive and negative patients (P>0.05). After initial periodontal treatment, 12 out of the 21 EBV-1 positive CP patients did not show detectable EBV-1 in subgingival samples.

CONCLUSION

nPCR plus RFLP analysis is a sensitive, specific and stable method to detect EBV-1 and EBV-2 in subgingival samples. Subgingival infection with EBV-1 is closely associated with chronic periodontitis. Infection of EBV in subgingival samples was correlated with BOP.

Epstein-Barr virus in oral diseases

Epstein-Barr virus (EBV), a B-lymphotropic gamma-herpesvirus, causes infectious mononucleosis and oral hairy leukoplakia, and is associated with various types of lymphoid and epithelial malignancies. Saliva is the main vehicle for EBV transmission from individual to individual. Recent studies have also implicated EBV in the pathogenesis of advanced types of periodontal disease. EBV DNA is detected in 60-80% of aggressive periodontitis lesions and in 15-20% of gingivitis lesions or normal periodontal sites. The periodontal presence of EBV is associated with an elevated occurrence of periodontopathic anaerobic bacteria. Moreover, EBV active infection occurs in approximately 70% of symptomatic and large-size periapical lesions. EBV and cytomegalovirus often co-exist in marginal and apical periodontitis. Periodontal therapy can markedly suppress the EBV load in periodontal pockets as well as in saliva, which has the potential to reduce the risk of viral transmission between close individuals. EBV proteins up-regulate cytokines and growth factors, which seem to play a central role in the proliferative response of tongue epithelial cells in oral hairy leukoplakia and in the cell-transformation process of EBV-associated malignancies. Further research is needed to identify the full range of EBV-related diseases in the human oral cavity.

Prevalence of some herpesviruses in gingival crevicular fluid

BACKGROUND

The herpesviruses, ancient pathogens which have co-evoluted with human, are etiologically associated with a number of diseases, from asymptomatic to oncogenic and mortal diseases. It seems that some of them have also an important role in the pathogenesis of human periodontal disease.

OBJECTIVE

This study aimed to determine the prevalence of Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), human herpesvirus 8 (HHV-8) and human cytomegalovirus (HCMV) in gingival crevicular fluid (GCF) and, eventually, to find the correlation between specific virus types and clinical parameters which are important in periodontitis, like plaque index (PI), gingival index (GI) and probing depth (PD).

STUDY DESIGN

A polymerase chain reaction (PCR) and digestion of PCR products with restriction endonuclease were employed to identify the presence of EBV, HHV-6, HHV-8 and HCMV.

RESULTS

Out of 66 samples of GCF taken from the patients with periodontal disease, EBV was found in 29 (43.9%), HHV-6 in 16 (24.2%) and HCMV in 2 (3%) samples, while in the samples of healthy persons, these viruses were not found. HHV-8 was detected neither in the patients with periodontitis nor in healthy control group. More positive results were found in clinical samples taken from people with higher PI and GI and in the samples taken from the patients with medium PD (PD=3-6mm). In all HHV-6 positive samples, we found only variant A; as for EBV positive samples, type A and type B were identified and also co-infection with the two types. It seems that there is a correlation between PI, PD and EBV types, but no correlation was found between EBV types and GI or HHV-6 types and PI, PD, GI.

CONCLUSIONS

The present findings confirm some association between herpesviruses and human periodontitis.

Viruses in periodontal disease - a review

The purpose of this review was to evaluate the evidence supporting the hypothesis that viral infection plays a role in the development of periodontitis. An involvement in periodontal diseases has been suspected specifically for human immunodeficiency virus (HIV) and herpes viruses. An association has been demonstrated between HIV infection and some distinct forms of periodontal infection, i.e. necrotizing lesions. Furthermore, reports of increased prevalence and severity of chronic periodontitis in HIV-positive subjects suggests that HIV infection predispose to chronic periodontitis. Several studies, most of them from the same research group, have demonstrated an association of herpesviruses with periodontal disease. Viral DNA have been detected in gingival tissue, gingival cervicular fluid (GCF) and subgingival plaque from periodontaly diseased sites. In addition markers of herpesviral activation have been demonstrated in the GCF from periodontal lesions. Active human cytomegalovirus (HCMV) replication in periodontal sites may suggest that HCMV re-activation triggers periodontal disease activity. Concerns regarding sampling, methods and interpretation cast doubts on the role of viruses as causes of periodontal disease.

Real-time polymerase chain reaction quantification of Epstein-Barr virus in chronic periodontitis patients

BACKGROUND

Although herpes viruses have been implicated in the pathogenesis of chronic and aggressive periodontitis, few data in the literature refer to quantification of these viruses in periodontal sites, especially in relation to serological findings.

OBJECTIVE

The aim of the present study was to compare Epstein--Barr virus (EBV) DNA load in subgingival specimens from chronic periodontitis patients and in periodontally healthy subjects, in relation to serologic testing of IgM and IgG antibodies to EBV.

METHODS

A total of 22 chronic periodontitis patients and 13 controls participated in the present study. Seventy-nine subgingival specimens (one pooled, one from a deep and one from a shallow site), sampled with paper points, were analysed with real-time polymerase chain reaction for EBV. Subjects were also examined for anti-EBV IgG and IgM levels in serum, using an enzyme-linked immunosorbent assay.

RESULTS

One subject was seronegative for EBV. Three subjects (one patient and two controls) displayed anti-EBV IgM. Their data were excluded from further analysis. All three displayed EBV in their subgingival samples. Nine out of the remaining 20 chronic periodontitis patients and 10 out of 11 controls did not display EBV subgingivally. A statistically significant difference in viral load was observed between pooled and shallow-pocket samples from periodontitis patients but not between samples from deep and shallow pockets (Kruskall--Wallis anova, Dunn's multiple comparisons test).

CONCLUSIONS

Data from the present study do not strongly support the pathogenetic significance of EBV in chronic periodontitis lesions. The data do, however, suggest that parallel serological assessments provide a useful insight into the association of viruses with periodontal disease.

Photodynamic therapy for periodontal diseases: State of the art

BACKGROUND

Photodynamic killing of periodontopathogenic bacteria may be an alternative to the systemic application of antibacterial drugs used in the treatment of periodontal diseases. Even though the method is still in the experimental stage, increasing bacterial resistance problems may promote the introduction of photodynamic therapy (PDT) into periodontal practice.

AIM

In this review a literature survey is given of PDT as seen from a periodontal perspective.

METHODS

In this review, the present knowledge and experience of PDT is summarized. Literature data are presented on drawbacks of conventional antibiotics, the mechanism of PDT, bactericidal effects of PDT as well as results of clinical efforts. The future prospects of the method are discussed.

RESULTS

The application of photosensitizing dyes and their excitation by visible light enables effective killing of periodontopathogens. Encouraging studies using PDT in periodontitis and in peri-implantitis are known.

CONCLUSION

Even though PDT is still in experimental stages of development and testing, the method may be an adjunct to conventional antibacterial measures in periodontology. Clinical follow-up studies are needed to confirm the efficacy of the procedure.

Association between human herpesviruses and the severity of periodontitis

BACKGROUND

Herpesviruses may play roles in the development of periodontal diseases. The present study evaluated the relationships between herpesviruses and the severity of periodontitis.

METHODS

Periodontal status in terms of gingival inflammation, bleeding on probing, probing depth, and clinical attachment loss of 20 participants was evaluated. The presence of herpes simplex virus (HSV), human cytomegalovirus (HCMV), or Epstein-Barr virus type 1 (EBV-1) in six subgingival plaques from each participant was examined by nested-polymerase chain reaction techniques.

RESULTS

Among the 120 sites examined, the prevalence of HCMV (51.7%) was higher than HSV (30.8%) followed by EBV-1 (4.2%). The prevalence of HSV or HCMV was significantly higher in the subgroups that had lower plaque index (<1). However, the prevalence of HSV was significantly higher in the subgroup that had higher gingival index (> or =2), positive bleeding on probing, deeper probing depth (> or =4 mm), or higher clinical attachment loss (> or =4 mm). Moreover, the prevalence of EBV-1 was significantly higher in the subgroup that had higher probing depth (> or =4 mm). Coinfection of HSV and HCMV was significantly associated with the sites that had higher gingival index (> or =2) or positive bleeding on probing. Coinfection of any two herpesviruses was also associated with higher probing depth (> or =4 mm) or higher clinical attachment loss (> or =4 mm).

CONCLUSIONS

This study demonstrated that HSV is related to the severity of periodontal diseases in terms of clinical attachment loss. Coinfection of any two herpesviruses may also play roles.

TT virus infection of periodontal tissues: a controlled clinical and laboratory pilot study

BACKGROUND

A novel single-strand, circular DNA virus has been recently isolated and named TT virus (TTV). It has been demonstrated that peripheral blood cells harbor TTV DNA, suggesting that the virus might replicate in lymphoid cells and contribute to lymphocyte imbalances with consequent immunosuppressive effects. The purpose of this study was to investigate the prevalence of TTV DNA in healthy and periodontally compromised subjects, evaluating the presence of the virus in the gingiva and saliva, and comparing virological results with clinical data.

METHODS

Twenty-one patients (seven males and 14 females, aged 25 to 76 years) were enrolled in the study. Eleven subjects were diagnosed with moderate periodontitis, while 10 were periodontally healthy. A sample of saliva was taken from each patient before recording the periodontal data; subsequently, a gingival biopsy was performed. A real-time polymerase chain reaction was used to quantify the presence of TTV DNA in saliva and gingival specimens.

RESULTS

A statistically significant association was found between TTV in gingival tissue and the presence of periodontitis (P = 0.0351), while no association was observed between TTV in saliva and the presence of periodontitis (P = 0.4762).

CONCLUSIONS

A new DNA virus (TTV) was first identified in the gingival tissue and was found to be significantly associated with the presence of periodontitis. These findings need to be investigated in further studies.

Human cytomegalovirus-associated periodontitis in renal transplant patients

BACKGROUND

Human cytomegalovirus (HCMV) infection is associated with renal transplant failure. Periodontal pockets may be reservoirs for HCMV replication.

OBJECTIVES

This study was done to determine active HCMV replication in saliva and gingival crevicular fluid of renal transplant patients affected by periodontitis.

METHODS

HCMV pp67-mRNA amplification was analyzed in oral fluids of 38 transplant recipients at 6 months' posttransplantation. Patients received antiviral therapy until 3 months' posttransplantation. The HCMV-positive cell line VR-977 was the positive control, and oral fluids from healthy volunteers served as the negative control. Periodontitis was diagnosed by clinical examination. Serum HCMV IgG and IgM were analyzed to differentiate recent and latent infection.

RESULTS

Prevalence of gingival overgrowth was 68.4%. HCMV gene transcripts were detected in the saliva of 21% and the gingival crevicular fluid of 18% of patients. All patients (100%) with HCMV pp67-mRNA detected in saliva demonstrated clinical manifestations of viral infection, as did 86% of patients with HCMV pp67-mRNA detected in the gingival crevicular fluid. Serum IgM was positive in 7.9% of patients and IgG in 65.8%; however, associations with active mRNA replication were not statistically significant.

CONCLUSIONS

Renal transplant patients affected by periodontitis are at risk of viral replication within the periodontal tissues despite antiviral therapy. This study suggests that use of HCMV pp67-mRNA detection in saliva and gingival crevicular fluid provides markers of active viral infection, and evidence for a link between HCMV-associated periodontitis and renal transplant complications.

Detection of Epstein-Barr virus in saliva by real-time PCR

The purpose of this investigation was to assess the salivary levels of Epstein-Barr virus (EBV) in patients with periodontitis using real-time PCR. EBV was detected in 16 out of 33 (48.5%) periodontitis patients and in 3 out of 20(15%) healthy subjects. The baseline mean values for bleeding on probing in EBV-positive patients were significantly higher than those in EBV-negative patients. A significant decrease in EBV levels was observed after initial periodontal treatment. Our findings indicate that levels of EBV in saliva may reflect the status of periodontal inflammation.

Relationship between Porphyromonas gingivalis, Epstein-Barr virus infection and reactivation in periodontitis

The aim of this study was to assess the relationship-between Porphyromonas gingivalis, Epstein-Barr virus (EBV) infection and reactivation in periodontitis using real-time PCR. The mean proportion of P. gingivalis cells to total bacterial cells in the saliva from EBV-positive periodontitis patients was significantly higher than that in saliva from EBV-negative patients. An EBV-positive B-cell line was used to determine whether P. gingivalis sonicate induced reactivation of EBV, using real-time PCR to measure the virus genome in the culture medium. A significant increase in EBV numbers was observed after the stimulation with P. gingivalis sonicate. These findings suggest that the interaction between EBV and P. gingivalis is bi-directional, with EBV reactivation suppressing host defenses and permitting overgrowth of P. gingivalis, and P. gingivalis having the potential to induce EBV reactivation.

Update on general health risk of periodontal disease

OBJECTIVES

To review the potential of periodontal infections to cause nonoral diseases. Therapeutic recommendations are provided to help patients and dental practitioners prevent systemic complications from periodontal infections.

FINDINGS

Systemic diseases from oral bacteria are mostly caused by transient bacteraemias, which can occur spontaneously from dental foci of infection, from mastication, brushing, flossing or other daily manipulations, or from dental treatments. Examples of systemic infections that may involve oral microorganisms include infective endocarditis, aspiration pneumonia, HIV-related disseminated candidiasis and cancrum oris, septicaemia associated with cancer chemotherapy and radiotherapy, necrotising faciitis and various other life-threatening infections. Inflamed gingiva constitutes a significant reservoir for herpes viruses, which have the potential to cause serious systemic diseases in immunocompromised patients. Periodontal disease may also aggravate chronic insulin insensitivity and thus interfere with glycaemic control in diabetic patients. Controversy surrounds the involvement of periodontal infections in coronary heart disease.

CONCLUSIONS

Cumulative evidence suggests that periodontal disease can be an important cause of morbidity and mortality of various systemic diseases, especially in individuals exhibiting compromised host defence. Maintaining a healthy dentition and periodontium by means of daily oral hygiene practice and regular professional care is the most effective way of preventing systemic diseases from oral infections.

Cytomegalovirus-induced gingival hyperplasia

We report a rare presentation of gingival hyperplasia associated with cytomegalovirus infection in a 33-year-old human immunodeficiency virus-infected man.

Gingival and other oral manifestations in measles virus infection

BACKGROUND

Measles is a highly contagious, viral infectious disease affecting mainly children and young adults. It is characterized by high fever, maculopapular rash, keratoconjunctivitis and pathognomonic oral Koplik's spots.

METHODS

During an outbreak of measles among soldiers in the Israeli military, patients were referred to one medical center where they were also examined for oral signs and symptoms of their illness.

RESULTS

We present a case of measles infection with distinct oral findings. These included Koplik's spots, various forms of ulcerations of the free mucosa, -like gingivitis and pericoronitis. All oral lesions resolved after cessation of systemic illness.

CONCLUSIONS

The measles virus is associated with a transient inhibition of the host response. Immunosuppression may create the necessary condition for the proliferation of pathobacteria associated with the observed pericoronitis and the other gingival lesions.

A TEM/SEM study of the microbial plaque overlying the necrotic gingival papillae of HIV-seropositive, necrotizing ulcerative periodontitis

The purpose of this study was to examine by transmission (TEM) and scanning electron microscopy (SEM) the supragingival microbial plaque overlying the ulcerated gingival papillae of necrotizing ulcerative periodontitis (NUP) lesions in HIV-seropositive patients. The microbiota of NUP and HIV-seropositive patients with periodontitis has been reported to be similar to that of conventional periodontitis in non-infected subjects, although several investigators have also reported high recovery rates of microbes not generally associated with the indigenous oral microbial flora. Light and electron microscopic observations and microbial culture studies indicate a similar high prevalence of spirochetes in both necrotizing ulcerative gingivitis (NUG) and NUP. In addition, several studies have reported more frequent isolation of Candida albicans from diseased periodontal sites in HIV-seropositive patients than from non-diseased sites. Ten male and six female patients, each HIV-seropositive and exhibiting NUP, constituted the study population. Two biopsies of involved gingival papillae from between posterior teeth were obtained from each patient and processed for examination by both TEM and SEM. Microscopic examination revealed a surface biofilm comprised of a mixed microbial flora of various morphotypes in 81.3% of biopsy specimens. The subsurface flora featured dense aggregations of spirochetes in 87.5% of specimens. Zones of aggregated polymorphonuclear leukocytes and necrotic cells were also noted. Yeasts were observed in 65.6% of specimens and herpes-like viruses in 56.5% of the specimens. Collectively, except for the presence of yeast and viruses, the results suggest that the microbial flora and possibly the soft tissue lesions of NUP and necrotizing ulcerative gingivitis are very similar.

Activation of interleukin 1beta gene transcription by human cytomegalovirus: molecular mechanisms and relevance to periodontitis

In recent years, studies have demonstrated an association between human cytomegalovirus (HCMV) and destructive periodontal disease. It has been shown that reactivation of HCMV in periodontitis lesions may be related to progressing periodontal disease. Several possible mechanisms by which HCMV exerts periodontopathic potential have been previously proposed. These are reviewed and include the upregulation of bone resorptive cytokines such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) by active HCMV infection at the periodontitis site. This review focuses on the molecular basis of IL-1beta gene activation by HCMV immediate early (IE) gene products. A novel hypothesis is also described whereby HCMV plays a significant role in the pathogenesis of periodontal disease by the ability of its IE proteins to strongly transactivate IL-1beta gene expression. More studies are needed to further explore this hypothesis and clarify the association between HCMV and periodontitis.

HHV-6, HHV-7, HHV-8 in gingival biopsies from chronic adult periodontitis patients. A case-control study

BACKGROUND

Recent reports have suggested that various herpesviruses may be involved in the occurrence and progression of different forms of periodontal disease.

OBJECTIVE

The objective of the present study was to investigate the presence of the novel herpesviruses HHV-6, HHV-7 and HHV-8 in gingival biopsies from patients affected by chronic adult periodontitis. As control, gingival biopsies from periodontally healthy subjects were analysed.

MATERIALS AND METHODS

Gingival biopsies were harvested from 23 volunteers: 13 patients affected by chronic adult periodontitis (CAP) and 10 periodontally healthy subjects. Each CAP patient contributed two biopsies involving the epithelium and connective tissue facing the sulcus/periodontal pockets: one biopsy from a site having a probing pocket depth (PPD) > or =5 mm and presenting with bleeding upon probing (affected site) at the time of biopsy collection, and the other biopsy from a site with PPD< or =3 mm and without bleeding on probing (nonaffected site). After DNA extraction, nested PCR was used in herpesvirus identification.

RESULTS

HHV-6 DNA sequences were detected in one non-affected site (8%) and no affected sites (0%) of CAP patients. One biopsy (10%) in healthy subjects revealed HHV-6 positivity. Tissue specimens in 10/13 CAP patients (77%) and 7/10 healthy subjects (70%) contained HHV-7 DNA. HHV-7 prevalence in affected and nonaffected sites of CAP patients was 77% and 54%, respectively. HHV-8 was detected in 7.7% of CAP patients and 0% of healthy subjects.

CONCLUSIONS

Gingival tissue may act as a reservoir for HHV-7. A high prevalence of HHV-7 was detected in both periodontally diseased and healthy individuals. The prevalence of HHV-6 and -8 was similarly low in both groups. Our data do not support an association of investigated herpesvirus species with destructive periodontal disease.

In vitro effect of oral antiseptics on human immunodeficiency virus-1 and herpes simplex virus type 1

AIM

The antiviral effectiveness of widely used commercial mouthrinses has not been well studied. A project was undertaken to evaluate and compare the in vitro antiviral effectiveness of essential oil-containing mouthrinses (LA & TLA) and chlorhexidine mouthrinses (PX & CHX) on 2 different enveloped viruses, human immunodeficiency virus (HIV-1) and Herpes simplex virus (HSV-1) McIntyre strain.

METHOD

HIV-1(89.6) (1x10(5)/ml) and HSV-1 (1x10(6)/ml) in RPMI-1640 medium were treated with two commercially available forms of LA & TLA (tartar control LA), and 2 formulations of chlorhexidine [(PX), 0.12% chlorhexidine & (CHX), 0.2% chlorhexidine] for 30 sec. The antiviral effect was estimated by inhibition of the syncytia formation or the cytopathic effect (CPE) for HIV-1 on MT-2 cells and by inhibition of the plaque formation for HSV-1 on Vero cell monolayers.

RESULTS

Undiluted LA, TLA, PX and CHX completely inhibited both HIV-189.6 and HSV-1 McIntyre strain. PX and CHX inhibited HIV-1 up to 1:4 dilution, whereas, LA and TLA inhibited HSV-1 up to 1:2 dilution. The antiviral effects of LA and TLA were found to be similar and also the antiviral effect of PX and CHX were also found to be comparable.

CONCLUSIONS

The methods used in this investigation allow easy and reproducible evaluations of antiviral efficacy. The anti-HIV-1 and anti-HSV-1 effects of LA, TLA, PX and CHX as evidenced in our in vitro study suggest that we should investigate potential in vivo effects during the use of essential oil-containing or chlorhexidine containing products when used by patients as mouthrinses. If the clinical studies confirm the in vitro data, pre-procedural use by clinicians may be beneficial in reducing viral contamination of bio-aerosols during the delivery of dental care.

Is herpes simplex virus associated with pulp/periapical inflammation?

OBJECTIVES

This study focuses on the detection of herpes simplex virus (HSV) DNA in dental pulp and inflamed periapical tissue.

STUDY DESIGN

Dental pulp tissue (vital and necrotic) and periapical tissue samples were collected under strictly sterile conditions and examined for the presence of HSV DNA. Saliva samples were also examined for the presence of the viral DNA. The polymerase chain reaction assay was used to detect viral DNA. Blood samples were collected, and the enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies against HSV was carried out.

RESULTS

According to the ELISA test, 19 of the 23 blood samples were IgG-positive and IgM-negative to HSV, whereas 4 were IgG-negative and IgM-negative. HSV DNA was not detected in the tissue and the saliva samples tested.

CONCLUSION

HSV is not present and therefore is probably not involved in the pathology of tooth neural tissue.

Herpesviruses in HIV-periodontitis

BACKGROUND/AIMS

Human herpesvirus-associated diseases exhibit elevated morbidity and mortality in patients infected with human immunodeficiency virus (HIV). This study aimed to investigate the occurrence of herpesviruses in HIV-periodontitis.

METHOD

Gingival biopsies from periodontitis lesions of 21 HIV-patients and 14 non HIV-patients were studied. Nested-polymerase chain reaction methods were employed to detect human cytomegalovirus, Epstein-Barr virus type 1 and 2 (EBV-1, EBV-2), herpes simplex virus, human herpes virus (HHV)-6, HHV-7 and HHV-8.

RESULTS

Gingival biopsies from HIV-periodontitis lesions showed on average 4.0 herpesvirus species and gingival biopsies from HIV periodontitis lesions of non-HIV patients revealed an average of 1.9 herpesvirus species (p<0.001). Occurrence of 4 to 6 different herpesviruses was more common in HIV- than in non HIV-gingival biopsies (71% vs. 7%) (p<0.001). EVB-2 was detected in 12 (57%) biopsies from HIV-periodontitis but was absent in non HIV-periodontitis biopsies (p= 0.002). HHV-6 also occurred in significantly higher frequency in HIV-periodontitis (71%) than in non HIV-periodontitis (21%) (p=0.01). HHV-8 was detected only in biopsies from HIV-periodontitis lesions..

CONCLUSION

HIV-periodontitis seems to be associated with elevated occurrence of EBV-2, HHV-6 and herpesvirus co-infections compared to periodontitis in non-HIV-patients. The periodontopathic significance of herpesviruses in HIV-periodontitis constitutes a research topic of considerable interest.

Herpesviruses: a unifying causative factor in periodontitis?

Human cytomegalovirus and Epstein-Barr virus type 1 are discussed in this review as they relate to destructive periodontal disease in humans. Genomes of the two herpesviruses occur frequently in severe adult periodontitis, localized and generalized juvenile periodontitis, Papillon-Lefèvre syndrome periodontitis, Down's syndrome periodontitis, HIV-associated periodontitis and acute necrotizing ulcerative gingivitis. Herpesvirus infections generally involve a mild or asymptomatic primary phase followed by an asymptomatic latent phase interrupted sporadically by periods of activation, where viral replication and possibly clinical disease become manifest. Herpesvirus reactivation is triggered by a number of immunosuppressing factors, some of which have also been shown to be risk indicators of periodontal disease. Available evidence argues for the involvement of active cytomegalovirus infection in the initiation and progression of localized juvenile periodontitis and possibly other types of periodontal disease. In periodontal disease, herpesviruses may cause release of tissue-destructive cytokines, overgrowth of pathogenic periodontal bacteria, and initiation of cytotoxic or immunopathogenic events. Understanding the significance of herpesviruses in the causation and pathogenesis of destructive periodontal diseases may have important implications in future prevention and treatment of the diseases.