Exfoliated oral mucosa cells as bioindicators of short- and long-term systemic titanium contamination.

BACKGROUND: Humans are exposed to exogenous sources of titanium-containing particles that can enter the body mainly by inhalation, ingestion, or dermal absorption. Given the widespread use of biomaterials in medicine, the surface of a titanium (Ti) biomedical device is a potential endogenous source of Ti ions and/or Ti-containing particles, such as TiO2 micro-(MPs) and nano-particles (NPs), resulting from biotribocorrosion processes. Ti ions or Ti-containing particles may deposit in epithelial cells of the oral mucosa, and the latter may therefore serve as bioindicators of short and long-term systemic Ti contamination. The aim of the present study was to histologically and quantitatively evaluate the presence of Ti traces in cells exfoliated from the oral mucosa as possible bioindicators of systemic contamination with this metal at short and long-term experimental time points METHODS: Thirty Wistar rats were intraperitoneally injected with a suspension of titanium dioxide (TiO2) (0.16 g/100 g body weight of TiO2 in 5 ml of NaCl 0.9%) using 5 nm NPs (Group: TiO2-NP5; n = 10), 45 µm MPs (Group: TiO2-MP45; n = 10), or vehicle alone (Control group; n = 10). At one and six months post-injection, right-cheek mucosa cells were obtained by exfoliative cytology using a cytobrush; they were spray fixed and stained using Safranin or the Papanicolaou technique. The smears were cytologically evaluated (light microscopy) to determine the presence of particulate material, which was also analyzed microchemically (SEM-EDS). Left-cheek mucosa cells were similarly obtained and re-suspended in 5 ml of PBS (pH: 7.2-7.4); the samples corresponding to each group were pooled together and analyzed spectrometrically (ICP-MS) to determine Ti concentration in each of the studied groups. Blood samples were obtained for histological determination of the presence of particulate material on Safranin-stained blood smears and determination of plasma concentration of Ti by ICP-MS RESULTS: Different size and shape metal-like particles were observed inside and outside epithelial cells in TiO2-NP5 and TiO2-MP45 cytological smears at both one and six months post-injection. EDS analysis showed the presence of Ti in the particles. ICP-MS revealed higher Ti concentrations in both TiO2 injected groups compared to the control group. In addition, Ti concentration did not vary with time or particle size. Monocytes containing particles were observed in blood smears of TiO2-exposed animals one- and six-months post-injection. Plasma levels of Ti were significantly higher in TiO2-NP5- and TiO2-MP45- exposed animals than in controls (p < 0.05), and Ti concentration was significantly higher at one month than at six months in both TiO2-exposed groups (p < 0.05). CONCLUSIONS: Cells exfoliated from the oral mucosa could be used as bioindicators of short- and long-term systemic contamination with Ti. Exfoliative cytology could be used as a simple, non-invasive, and inexpensive diagnostic method for monitoring biotribocorrosion of Ti implants and patient clinical follow-up.

Detection of Oral Human Papillomavirus (HPV) and its Clinical Importance.

Statement of the Problem: Human papillomavirus (HPV) has a tropism for the squamous epithelium and cause a wide range of diseases, from benign lesions to invasive tumors that can affect the oral cavity. Purpose: This study aimed to estimate HPV infection in compatible stomatological lesions. Materials and Method: A cross-sectional study was carried out from March 2017 to August 2019, which included patients who attended the Oral Medicine Department of the School of Dentistry of the University of Buenos Aires who presented oral manifestations compatible with HPV infection that accepted to be studied by histopathology and determination of viral genotype by polymerase chain reaction (PCR). The study was carried out from the biopsy fixed in formalin and included in paraffin, for histopathological study and the genotypification of HPV by genotype-specific PCR and/or sequencing of the L1 fragment. To confirm the negative cases hybrid capture method was also used. The 95% OR-IC was estimated. Results: 108 patients, 76 women and 32 men were studied, who underwent a clinical stomatological examination and genotyping of HPV (PCR-specific genotype), being positive for 60 patients and negative for 48. Among the positive cases (n= 60) 46.7% (n= 28) corresponded to elevated lesions infected with high-risk HPV genotypes, 43.3% (n= 26) to elevated lesions with low-risk HPV genotypes, regarding flat lesions it was found that 5% (n=3) corresponded with high-risk HPV genotypes and another 5% (n=3) with low-risk genotypes, with OR 1,076 95% CI (0.1993-5.818). The HPV genotypes found were 2, 6, 11, 13, 16, 18, 26, 31, 32, 33, 35, 51, 58, 64 and 72. Conclusion: Our results estimated an association between white, bright, and elevated oral lesions and the presence of high-risk HPV.

Exfoliative cytology and titanium dental implants: a pilot study.

BACKGROUND: Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri-implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri-implant oral mucosa around titanium dental implants. METHODS: The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri-implantitis. Cytologic samples of the peri-implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma-mass spectrophotometry. RESULTS: Metal-like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri-implant mucosa of both patients with and without peri-implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri-implantitis group compared with the group without peri-implantitis; no traces of titanium were observed in controls. CONCLUSIONS: Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri-implant mucosa.

Miasis bucal: revisión de la literatura y presentación de dos casos clínicos / Oral myiasis: a review of the literature and report of two clinical cases

La miasis bucal es una enfermedad tropical, producida por ectoparásitos que se encuentra en resurgimiento, de acuerdo a diversos reportes. Se manifiesta como tumores ulcerados dolorosos, principalmente de localización palatina. Debido a esto, es importante que el odontólogo tenga conocimiento de sus aspectos epidemiológicos, clínicos, diagnósticos, terapéuticos y preventivos, ya que en la cavidad bucal se pueden presentar manifestaciones de dicha patología. En este artíciulo se expondrán las manifestaciones clínicas de dos pacientes que estudiamos y tratamos en la Cátedra de Clínica Estomatológica de la Facultad de Odontología de Buenos Aires.

Ameloblastoma desmoplásico: diagnóstico precoz: presentación de un caso clínico / Desmoplastic ameloblastoma: early diagnosis: report of a clinical case

El ameloblastoma es una neoplasia benigna, localmente invasora, originada a partir de restos de epitelio odontogénico o del revestimiento epitelial de un quiste dentígero. Es la neoplasia odontogénica más frecuente de la mandíbula. Actualmente la OMS reconoce 4 tipos de ameloblastomas: el sólido multiquístico, el periférico o extraóseo, el desmoplásico y el uniquístico. El tipo desmoplásico es poco frecuente y presenta características clínicas, radiográficas e histológicas distintivas , aunque su comportamiento es similar al del tipo sólido-multiquístico, por lo que el tratamiento quirúrgico recomendado no varía. Se presenta un caso clínico donde el diagnóstico precoz fue fundamental para realizar un tratamiento conservador, rápido y con mínimas consecuencias estéticas y psicológicas para el paciente.(AU)

Ameloblastoma desmoplásico: diagnóstico precoz: presentación de un caso clínico / Desmoplastic ameloblastoma: early diagnosis: report of a clinical case

El ameloblastoma es una neoplasia benigna, localmente invasora, originada a partir de restos de epitelio odontogénico o del revestimiento epitelial de un quiste dentígero. Es la neoplasia odontogénica más frecuente de la mandíbula. Actualmente la OMS reconoce 4 tipos de ameloblastomas: el sólido multiquístico, el periférico o extraóseo, el desmoplásico y el uniquístico. El tipo desmoplásico es poco frecuente y presenta características clínicas, radiográficas e histológicas distintivas , aunque su comportamiento es similar al del tipo sólido-multiquístico, por lo que el tratamiento quirúrgico recomendado no varía. Se presenta un caso clínico donde el diagnóstico precoz fue fundamental para realizar un tratamiento conservador, rápido y con mínimas consecuencias estéticas y psicológicas para el paciente.

Estudio de la prevalencia del secundarismo sifilítico bucal en dos servicios de estomatología de la ciudad de Buenos Aires / Study of prevalence of oral second-stage Syphilis, in two departments of stomatology, in the city of Buenos Aires

Las manifestaciones bucales del secundarismo sifilítico, son una de las formas clínicas que ermiten el diagnóstico presuntivo de la enfermedad. Estas lesiones son patognomónicas, pero no se han encontrado estudios que relacionen estas lesiones con su distribución y localización en la mucosa bucal. El objetivo de este estudio, es el de distinguir las lesiones bucales observadas, relacionándolas con las adenopatías y los niveles serológicos de V.D.R.L.

Amiloidosis localizada en lengua: presentación de un caso clínico / Localized tongue amyloidosis: report of a clinical case

La amiloidosis es una enfermedad definida por la presencia de acumulaciones de una glucoproteína fibrosa en los espacios extracelulares. Estos depósitos se tiñen con rojo Congo y tienen una característica birrefringencia de color verde manzana a la luz polarizada. El compromiso de la lengua es, casi universalmente, secundario a la afectación sistémica. El promedio de sobrevida de los pacientes con amiloidosis sistémica es entre 5 a 15 meses, mientras que aquellos con forma localizada tienen un excelente pronóstico. Clinicamente, cuando afecta mucosa bucal, la lengua es la localización electiva, donde el signo clínico más relevante es la macroglosia. En este artículo se presenta un caso con amiloidosis localizada en lengua como hallazgo clínico realico únicamente por la palpación de los nóduloso amiloides. La ausencia de amilodosis sistémica ofrece un pronóstico mucho más favorable y puede ser tratado con un tratamiento quirúrgico localizado

Amiloidosis localizada en lengua: presentación de un caso clínico / Localized tongue amyloidosis: report of a clinical case

La amiloidosis es una enfermedad definida por la presencia de acumulaciones de una glucoproteína fibrosa en los espacios extracelulares. Estos depósitos se tiñen con rojo Congo y tienen una característica birrefringencia de color verde manzana a la luz polarizada. El compromiso de la lengua es, casi universalmente, secundario a la afectación sistémica. El promedio de sobrevida de los pacientes con amiloidosis sistémica es entre 5 a 15 meses, mientras que aquellos con forma localizada tienen un excelente pronóstico. Clinicamente, cuando afecta mucosa bucal, la lengua es la localización electiva, donde el signo clínico más relevante es la macroglosia. En este artículo se presenta un caso con amiloidosis localizada en lengua como hallazgo clínico realico únicamente por la palpación de los nóduloso amiloides. La ausencia de amilodosis sistémica ofrece un pronóstico mucho más favorable y puede ser tratado con un tratamiento quirúrgico localizado (AU)