Relation between buccal protozoa and pH and salivary IgA in patients with dental prothesis

Abstract

Sir,Entamoeba gingivalis and Trichomonas tenax are human buccal protozoa. They live in dental tartar, in the necrotic mucosa of the cells and the gingival fringes of the gums 6 .The complexity of the oral environment and the multifactorial nature of the caries lesion, with the consequent loss of dental pieces, requires the cooperation of other disciplines such as Microbiology, Chemistry and Dietetics. Both partial and total loss of dental pieces produce modifications in buccal biotic conditions 1 . Some investigators think that E. gingivalis is an agent which causes periodontitis 7 , while others consider it an opportunist capable of survive in the medium induced by periodontal disease 5 .T. tenax, in spite of being considered as a commensal might take part in the first phases of the process of destruction of periodontal tissues 6 owing to the finding of an acid phosphatase 3 , a surface protein similar to fibronectine 6 and an important collagenolytic activity 6 .The objetive was to determine the frequency of these two protozoa and their relation with salivary IgA and with salivary pH in patients with dental prothesis.Fifty adult patients with either fixed or mobile prothesis were selected. Tartar and/or dental plaque samples of the 4 inferior incisors were obtained by means of a scaler, as well as a saliva sample was taken from each of the patients. Both were collected in the morning with no previous brushing or, in other cases, after a period of at last three or four hours after the last buccal hygiene.Tartar, as well as dental plaque were diluted with sterile physiologic solution and was observed through an optical microscope (100x and 400x).There was a previous microscopic observation of saliva followed by another observation after 2000 r.p.m. centrifugation during 5 minutes (100x and 400x) to identify protozoa.Both samples were coloured with Gomori trichromic stain 11 and cultured at 37 °C in the following specific media: Bacto Endamoeba Medium for E. gingivalis and Diamond medium 4 for T. tenax. Cultures were daily observed for 72 hours.In saliva samples, pH was determined by means of strips of indicant paper (V.N.: 6/0-7/5), and secretory IgA concentration was determined by the radial immunodiffusion method 10 (V.N.: 20-40 mg/dl).The statistical analysis was performed by the χ 2 test (signification level 0/05) so as to study the association between pH and IgA with the presence of parasite 2 .Out of the 50 examined patients, 36 (72%) presented parasites, 29 were monoparasitized, 26 presented E. gingivalis and 3 presented T. tenax; the other 7 presented both protozoa.The frequency of E. gingivalis in the population studied was 66% and 20% for T. tenax. Both protozoa were predominant in the tartar sample, and/ or the dental plaque.The cultures performed for the search of T. tenax increased significantly the diagnostic sensitivity, since out of the 10 positive patients, 5 were diagnosed only through the culture. However, for E. gingivalis, neither the culture nor the trichromic coloration increased sensitivi...

The occurrence of Entamoeba gingivalis among patients with periodontal disease

“…it does not have resistant forms (cysts) recognizable in the clinical specimens, but only trophozoites, which vary in size from 10 to 35 µm [2,5,11]. This parasite inhabits the area around the teeth and gums, including the spaces between teeth, and especially in teeth cavities, dental tartar, necrotic mucosa of cells and the gingival fringes of the gums [11,17].…”

“…According to some studies, this amoeba is also an important agent in the induction of periodontitis. Still other researchers consider it merely an opportunist capable of surviving in the medium induced by periodontal disease [11,17]. It is known, however, that Entamoeba gingivalis cooperates with synergistic, symbiotic bacteria in engendering periodontal disease in hosts with low immunity [8].…”

Observation of trichomonads infection in a child with periodontitis by direct microscopy at the dental office

“…A direct examination, using phase-contrast optical microscopy with a magnification X1000, was performed in order to search for motile flagellate Trichomonas species trophozoites (Ponce de Leon et al . 2001). This method was employed to enable the use of the X100 oil immersion objective before fixing the cover glass over the slide, thereby avoiding dryness or alteration of parasitic structures (Abdel-Hamid, 1997).…”

“…Faculté de Chirurgie-dentaire, 3 chemin des Maraîchers, 31069 Toulouse, France. E-mail: martymat@hotmail.fr (Ponce de Leon et al 2001). This method was employed to enable the use of the X100 oil immersion objective before fixing the cover glass over the slide, thereby avoiding dryness or alteration of parasitic structures (Abdel-Hamid, 1997).…”

Current Global Status and the Epidemiology of Entamoeba gingivalis in Humans: A Systematic Review and Meta-analysis

“…The amoeba has been found scavenging in the healthy oral cavity, but there are still discrepancies regarding the true effect of the E. gingivalis on the hygienic status of the oral cavity (7,8). Some researchers suggest that this organism provokes periodontitis, while others remark that the protozoan is only an opportunistic survivor in the molecular milieu elicited by periodontal disease (9)(10)(11). However, it is recognized that E. gingivalis acts synergistically with symbiotic bacteria to cause periodontal disease in immunocompromised hosts (12).…”