Report of intraosseous intravascular papillary endothelial hyperplasia associated with an odontogenic cyst in the maxilla and literature review.

Intravascular papillary endothelial hyperplasia (IPEH) represents an uncommon reactive endothelial hyperplastic proliferation. A 46-year-old man experienced increased volume in the right maxilla, elevation of the nasal ala, and swelling of the hard palate with a reddish hue for 3 months. Computed tomography revealed an expansive hypodense region and cortical bone destruction associated with an impacted supernumerary tooth and an endodontically treated tooth. Under the differential diagnoses of a radicular cyst, dentigerous cyst, and ameloblastoma, an exploratory aspiration and incisional biopsy were performed. This revealed the formation of blood vessels of various diameters lined by endothelium, forming intravascular papillae positive for CD-34. The definitive diagnosis was IPEH, and the patient was treated by embolization and surgery. Histological analysis confirmed the presence of IPEH associated with an odontogenic cyst. After 12 months of follow-up, no recurrence was observed. Also, we reviewed case reports of IPEH affecting the maxilla and mandible. Fourteen intraosseous cases were reported in the maxilla and mandible, with a preference for males and affecting a wide age range. Complete surgical excision was the treatment of choice, and recurrences were not reported. The pathogenesis of IPEH is controversial and may originate from trauma or inflammatory processes. To the best of our knowledge, this is the first report of an association of IPEH with an odontogenic cyst. The importance of IPEH in the differential diagnosis of intraosseous lesions in the jaws is emphasized, and preoperative semiotic maneuvers are needed to prevent surgical complications.

Heat-killed Limosilactobacillus reuteri ATCC PTA 6475 prevents bone loss in ovariectomized mice: A preliminary study.

Osteoporosis is an important health problem that occurs due to an imbalance between bone formation and resorption. Hormonal deficiency post-menopause is a significant risk factor. The probiotic Limosilactobacillus reuteri has been reported to prevent ovariectomy (Ovx)-induced bone loss in mice and reduce bone loss in postmenopausal women. Despite the numerous health benefits of probiotics, as they are live bacteria, the administration is not risk-free for certain groups (e.g., neonates and immunosuppressed patients). We evaluated the effects of L. reuteri (ATCC PTA 6475) and its heat-killed (postbiotic) form on Ovx-induced bone loss. Adult female mice (BALB/c) were randomly divided into four groups: group C-control (sham); group OVX-C-Ovx; group OVX-POS-Ovx + heat-killed probiotic; group OVX-PRO-Ovx + probiotic. L. reuteri or the postbiotic was administered to the groups (1.3x109 CFU/day) by gavage. Bacterial morphology after heat treatment was accessed by scanning electron microscopy (SEM). The treatment started one week after Ovx and lasted 28 days (4 weeks). The animals were euthanized at the end of the treatment period. Bone microarchitecture and ileum Occludin and pro-inflammatory cytokines gene expression were evaluated by computed microtomography and qPCR techniques, respectively. The Ovx groups had lower percentage of bone volume (BV/TV) and number of bone trabeculae as well as greater total porosity compared to the control group. Treatment with live and heat-killed L. reuteri resulted in higher BV/TV and trabecular thickness than the Ovx group. The heat treatment caused some cell surface disruptions, but its structure resembled that of the live probiotic in SEM analysis. There were no statistical differences in Occludin, Il-6 and Tnf-α gene expression. Both viable and heat-killed L. reuteri prevented bone loss on ovariectomized mice, independently of gut Occludin and intestinal Il-6 and Tnf-α gene expression.

Clinicopathologic analysis of oral dermoid and epidermoid cysts: a Brazilian multicenter study.

Dermoid cysts (DCs) and epidermoid cysts (ECs) are uncommon developmental cysts affecting the oral cavity. This study aims to evaluate patients with oral DCs and ECs and their demographic and clinicopathologic features. A retrospective descriptive cross-sectional study was performed. A total of 105,077 biopsy records of oral and maxillofacial lesions from seven Brazilian oral pathology centers were analyzed. All cases diagnosed as oral DCs and ECs were reviewed, and clinical, demographic, and histopathological data were collected. The series comprised 32 DCs (31.4%) and 70 ECs (68.6%). Most of the DCs occurred on the floor of the mouth (n = 14; 45.2%) of women (n = 17; 53.1%) with a mean age of 34.6 ± 21.6 years. All DCs were lined partially or entirely by stratified squamous epithelium (100%). Chronic inflammatory cells, melanin pigmentation, multinucleated giant cell reaction, and cholesterol clefts were observed in the fibrous capsule . Most of the ECs affected the labial mucosa (n = 20; 31.7%) of men (n = 39; 56.5%) with a mean age of 48.0±19.8 years. Microscopically, most ECs (n = 68; 97.1%) were lined entirely by stratified squamous epithelium. Two cysts (2.9%) showed areas of respiratory metaplasia. Chronic inflammatory cells, melanin pigmentation, multinucleated giant cell reaction, and cholesterol clefts were also observed in the fibrous capsule. Conservative surgical excision was the treatment of choice in all cases. Oral DCs and ECs are uncommon and often clinically misdiagnosed lesions. Clinicians should consider DCs and ECs in the differential diagnosis of soft tissue lesions in the oral cavity, mainly located on the floor of the mouth and labial mucosa.

Contribution of public oral pathology services to the diagnosis of oral and oropharyngeal cancer in Brazil.

This study aimed to evaluate the contribution of oral and maxillofacial pathology laboratories (OMPLs) in Brazilian public universities to the diagnosis of lip, oral cavity, and oropharyngeal squamous cell carcinoma (SCC). A cross-sectional study was performed using biopsy records from a consortium of sixteen public OMPLs from all regions of Brazil (North, Northeast, Central-West, Southeast, and South). Clinical and demographic data of patients diagnosed with lip, oral cavity, and oropharyngeal SCC between 2010 and 2019 were collected from the patients' histopathological records. Of the 120,010 oral and maxillofacial biopsies (2010-2019), 6.9% (8,321 cases) were diagnosed as lip (0.8%, 951 cases), oral cavity (4.9%, 5,971 cases), and oropharyngeal (1.2%, 1,399 cases) SCCs. Most cases were from Brazil's Southeast (64.5%), where six of the OMPLs analyzed are located. The predominant profile of patients with lip and oral cavity SCC was Caucasian men, with a mean age over 60 years, low schooling level, and a previous history of heavy tobacco consumption. In the oropharyngeal group, the majority were non-Caucasian men, with a mean age under 60 years, had a low education level, and were former/current tobacco and alcohol users. According to data from the Brazilian National Cancer Institute, approximately 9.9% of the total lip, oral cavity, and oropharyngeal SCCs reported over the last decade in Brazil may have been diagnosed at the OMPLs included in the current study. Therefore, this data confirms the contribution of public OMPLs with respect to the important diagnostic support they provide to the oral healthcare services extended by the Brazilian Public Health System.

Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study.

OBJECTIVE: To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America. METHODS: A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square. RESULTS: In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD. CONCLUSIONS: In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

Oral solitary fibrous tumors: A collaborative clinicopathologic study of 19 cases.

OBJECTIVE: To report the clinicopathologic features of 19 oral solitary fibrous tumors (SFTs). METHODS: Clinical data were collected from the records of seven pathology services. All cases were re-evaluated by HE staining and confirmed by immunohistochemistry. RESULTS: The series comprised 11 females (57.9%) and 8 males (42.1%), with a mean age of 47.3 ± 14.7 years (range: 22-71 years) and a 1.3:1 female-to-male ratio. Most tumors affected the buccal mucosa (n = 7; 36.8%) and presented clinically as an asymptomatic solitary submucosal well-circumscribed nodule with coloration similar to the oral mucosa. Morphologically, most SFTs (n = 10; 52.6%) exhibited a classic hybrid pattern characterized by a well-circumscribed proliferation of densely cellular areas alternating with hypocellular areas in a variably collagenous vascular stroma. Remnants of accessory salivary glands were observed in two cases (n = 2; 10.5%). All tumors were positive for STAT6 and CD34 (n = 19; 100%). Outcome information was available from 6 patients (31.6%), with clinical follow-up ranging from 6 to 24 months (mean ± SD, 9.5 ± 6.8 months), and none developed local recurrence. CONCLUSIONS: Oral SFTs are rare and often clinically misdiagnosed. Pathologists should consider SFT in the differential diagnosis of oral spindle cell tumors. Accurate diagnosis requires careful morphological evaluation supported by immunohistochemical analysis.

Clinicopathologic analysis of oral dermoid and epidermoid cysts: a Brazilian multicenter study

Abstract Dermoid cysts (DCs) and epidermoid cysts (ECs) are uncommon developmental cysts affecting the oral cavity. This study aims to evaluate patients with oral DCs and ECs and their demographic and clinicopathologic features. A retrospective descriptive cross-sectional study was performed. A total of 105,077 biopsy records of oral and maxillofacial lesions from seven Brazilian oral pathology centers were analyzed. All cases diagnosed as oral DCs and ECs were reviewed, and clinical, demographic, and histopathological data were collected. The series comprised 32 DCs (31.4%) and 70 ECs (68.6%). Most of the DCs occurred on the floor of the mouth (n = 14; 45.2%) of women (n = 17; 53.1%) with a mean age of 34.6 ± 21.6 years. All DCs were lined partially or entirely by stratified squamous epithelium (100%). Chronic inflammatory cells, melanin pigmentation, multinucleated giant cell reaction, and cholesterol clefts were observed in the fibrous capsule . Most of the ECs affected the labial mucosa (n = 20; 31.7%) of men (n = 39; 56.5%) with a mean age of 48.0±19.8 years. Microscopically, most ECs (n = 68; 97.1%) were lined entirely by stratified squamous epithelium. Two cysts (2.9%) showed areas of respiratory metaplasia. Chronic inflammatory cells, melanin pigmentation, multinucleated giant cell reaction, and cholesterol clefts were also observed in the fibrous capsule. Conservative surgical excision was the treatment of choice in all cases. Oral DCs and ECs are uncommon and often clinically misdiagnosed lesions. Clinicians should consider DCs and ECs in the differential diagnosis of soft tissue lesions in the oral cavity, mainly located on the floor of the mouth and labial mucosa.

Contribution of public oral pathology services to the diagnosis of oral and oropharyngeal cancer in Brazil

Abstract This study aimed to evaluate the contribution of oral and maxillofacial pathology laboratories (OMPLs) in Brazilian public universities to the diagnosis of lip, oral cavity, and oropharyngeal squamous cell carcinoma (SCC). A cross-sectional study was performed using biopsy records from a consortium of sixteen public OMPLs from all regions of Brazil (North, Northeast, Central-West, Southeast, and South). Clinical and demographic data of patients diagnosed with lip, oral cavity, and oropharyngeal SCC between 2010 and 2019 were collected from the patients' histopathological records. Of the 120,010 oral and maxillofacial biopsies (2010-2019), 6.9% (8,321 cases) were diagnosed as lip (0.8%, 951 cases), oral cavity (4.9%, 5,971 cases), and oropharyngeal (1.2%, 1,399 cases) SCCs. Most cases were from Brazil's Southeast (64.5%), where six of the OMPLs analyzed are located. The predominant profile of patients with lip and oral cavity SCC was Caucasian men, with a mean age over 60 years, low schooling level, and a previous history of heavy tobacco consumption. In the oropharyngeal group, the majority were non-Caucasian men, with a mean age under 60 years, had a low education level, and were former/current tobacco and alcohol users. According to data from the Brazilian National Cancer Institute, approximately 9.9% of the total lip, oral cavity, and oropharyngeal SCCs reported over the last decade in Brazil may have been diagnosed at the OMPLs included in the current study. Therefore, this data confirms the contribution of public OMPLs with respect to the important diagnostic support they provide to the oral healthcare services extended by the Brazilian Public Health System.

Proliferative verrucous leukoplakia mimicking oral lichen planus: case report and literature review

This report presents the clinical, microscopic and immunohistochemical aspects of a case of proliferative verrucous leukoplakia (PVL) mimicking oral lichen planus (OLP) in a 66-year-old woman. We also review the literature reporting cases of PVL mimicking OLP, where we found a higher prevalence in women who do not consume tobacco or alcohol. The initial manifestation of lichenoid areas was around the age of 59, with the diagnosis of PVL being established on average 6 years later, while malignant transformation occurred in 8 of the 22 cases at an average of 3.7 years after the final diagnosis of PVL. We emphasize the need for a close follow-up of any patient presenting white lesions of the oral mucosa. Lesions that are clinically and microscopically compatible with lichenoid reactions or OLP must be investigated and differentiated from PVL, which has a worse prognosis.

Este relato apresenta os aspectos clínicos, microscópicos e imuno-histoquímicos de um caso de leucoplasia verrucosa proliferativa (LPV) mimetizando líquen plano oral (LPO) em uma paciente do sexo feminino de 66 anos. Também revisamos a literatura relatando casos de LPV mimetizando LPO, onde encontramos maior prevalência em mulheres que não consomem tabaco ou álcool, com manifestação inicial de áreas liquenoides por volta dos 59 anos, sendo estabelecido o diagnóstico de LPV em média 6 anos depois, enquanto a transformação maligna ocorreu em 8 dos 22 casos em média 3,7 anos após o diagnóstico final de LPV. Ressaltamos a necessidade de acompanhamento rigoroso de qualquer paciente que apresente lesões brancas da mucosa oral, devendo ser investigadas lesões clinicamente e microscopicamente compatíveis com reações liquenóides ou LPO e diferenciadas da LPV, que tem pior prognóstico

Este reporte presenta los aspectos clínicos, microscópicos e inmunohistoquímicos de un caso de leucoplasia verrugosa proliferativa (LVP) simulando liquen plano oral (LPO) en una paciente de 66 años. También revisamos la literatura reportando casos de LVP simulando LPO, donde encontramos una mayor prevalencia en mujeres que no consumen tabaco ni alcohol, con una manifestación inicial de áreas liquenoides alrededor de los 59 años, estableciéndose el diagnóstico de LVP en promedio 6 años después, mientras que la transformación maligna ocurrió en 8 de los 22 casos en un promedio de 3,7 años después del diagnóstico final de LVP. Resaltamos la necesidad de un seguimiento estrecho de todo paciente que presente lesiones blanquecinas de la mucosa oral, que las lesiones clínica y microscópicamente compatibles con reacciones liquenoides o LPO deben ser investigadas y diferenciadas de la LVP, que tienen peor pronóstico.

Effects of α and ß-adrenergic signaling on innate immunity and Porphyromonas gingivalis virulence in an invertebrate model.

To investigate the role of adrenergic signalling (AS) in the host immune response and Porphyromonas gingivalis virulence, we compared norepinephrine (NE) and isoproterenol (ISO) responses in Galleria mellonella. P. gingivalis infection was evaluated by survival; humoral immune responses (i.e. melanization and cecropin and gloverin mRNA expression); cellular immune responses (i.e. haemocyte count, nodulation by histology); and P. gingivalis recovery (CFU/mL). P. gingivalis was cultivated in the presence of ISO (PgISO) or NE and injected into the larvae for survival evaluation. Finally, we co-injected ISO and PgISO to evaluate the concomitant effects on the immune response and bacterial virulence. None of the ligands were toxic to the larvae; ISO increased haemocyte number, even after P. gingivalis infection, by mobilizing sessile haemocytes in a ß-adrenergic-specific manner, while NE showed the opposite effect. ISO treatment reduced larval mortality and the number of recovered bacteria, while NE increased mortality and showed no effect on bacterial recovery. ISO and NE had similar effects on melanization and decreased the expression of cecropin. Although co-cultivation with NE and ISO increased the gene expression of bacterial virulence factors in vitro, only the injection of PgISO increased larval death, which was partially reversed by circulating ISO. Therefore, α- and ß-adrenergic signalling had opposite effects after P. gingivalis infection. Ultimately, the catecholamine influence on the immune response overcame the effect of more virulent strains. The effect of AS directly on the pathogen found in vitro did not translate to the in vivo setting.

Outside the limits of bacterial viability: Postbiotics in the management of periodontitis.

Periodontitis is a major cause of tooth loss in adults worldwide and is caused by an unbalanced oral microbiota in a susceptible host, ultimately leading to tissue breakdown and bone loss. Traditionally, the treatment for periodontitis is scaling and root planing; however, some cases require adjuvant therapy, such as antibiotics administration or surgery. Various factors are involved in the pathogenesis and interact in an unpredictable way, increasing the complexity of the disease and making it difficult to manage. In this context, the administration of probiotics aimed at resolving bacterial dysbiosis and the associated dysregulation of the immune system has been employed in clinical trials with encouraging results. However, the use of viable microorganisms is not risk-free, and immunocompromised patients may develop adverse effects. Therefore, the use of inactivated microbial cells, cell fractions, or soluble products and metabolites of probiotics, known as postbiotics, has gained increasing attention. In this commentary, we present the current literature assessing the impact of postbiotics on the growth and metabolism of periodontal pathogens, as well as on the progression of periodontitis in rodents and humans. We also discuss the limitations of the available data and what the scientific community should consider in order to transfer this innovative therapeutic modality from the bench to the bedside.

Jaw osteosarcoma and pregnancy: a rare coexistence.

Osteosarcoma of the jaw represents less than 1% of all head and neck malignancies. This malignancy in pregnant women occurs in one per 1000 deliveries. We report a case of a 29-year-old woman, in the 33rd week of gestation, who presented with an expansive tumor destroying the maxillary alveolar bone, histologically composed of pleomorphic, round, spindle, or epithelioid cells and osteoid/chondroid matrix. Upon final diagnosis of osteosarcoma, the lesion was excised. To the best of our knowledge, only 10 cases of jaw osteosarcoma in pregnant women have been reported to date in the English language literature. The use of ancillary examinations, malignancy diagnosis, and cancer treatment can be challenging during pregnancy. Knowledge about jaw osteosarcoma in pregnancy can increase healthcare providers' awareness, avoid delays and misdiagnosis and potentially improve maternal and neonatal outcomes.

Erratum: Orofacial overgrowth with peripheral nerve enlargement and perineuriomatous pseudo-onion bulb proliferations is part of the PIK3CA-related overgrowth spectrum.

[This corrects the article DOI: 10.1016/j.xhgg.2020.100009.].

Oral Lymphoepithelial Cyst: A Collaborative Clinicopathologic Study of 132 Cases from Brazil.

The oral lymphoepithelial cyst (OLC) is an uncommon lesion whose pathogenesis remains poorly understood. The aim of this study was to report the clinicopathologic features of the OLCs and to verify a possible association between OLCs and subgemmal neurogenous plaque (SNP) in the posterior lateral region of the tongue. A retrospective descriptive cross-sectional study was carried out. A total of 106,282 biopsy records of oral and maxillofacial lesions from six oral pathology services in Brazil were analyzed. All cases of OLCs were reviewed, and clinical and histopathological data were collected. Immunohistochemical reactions for S-100 protein were performed to confirm the diagnosis of SNP. Among all lesions, there were 132 (0.11%) cases of OLCs. The series comprised 83 females (62.9%) and 49 males (37.1%), with a 1.7:1 female-to-male ratio and a mean age of 45.8 ± 17.7 years. Most cases involved the tongue (n = 80; 62.0%) and presented clinically as asymptomatic papules or nodules with a yellow or whitish color. Microscopically, most of the cysts were entirely lined by parakeratinized stratified epithelium (n = 89; 67.4%) and filled with desquamated cells, keratin debris, amorphous eosinophilic material, and inflammatory cells in varying amounts. Connection with the epithelium of oral mucosa was observed in 18 cases (13.6%). SNP was found in 9/80 (11.2%) cases involving the tongue. The clinical and demographic features of OLCs were similar to those described in previous studies. Overall, this lesion has a predilection for the posterior region of the tongue of female adults. Clinicians must include the OLC in the differential diagnosis of yellow/white papules and nodules of the oral cavity.

Jaw osteosarcoma and pregnancy: a rare coexistence

Osteosarcoma of the jaw represents less than 1% of all head and neck malignancies. This malignancy in pregnant women occurs in one per 1000 deliveries. We report a case of a 29-year-old woman, in the 33rd week of gestation, who presented with an expansive tumor destroying the maxillary alveolar bone, histologically composed of pleomorphic, round, spindle, or epithelioid cells and osteoid/chondroid matrix. Upon final diagnosis of osteosarcoma, the lesion was excised. To the best of our knowledge, only 10 cases of jaw osteosarcoma in pregnant women have been reported to date in the English language literature. The use of ancillary examinations, malignancy diagnosis, and cancer treatment can be challenging during pregnancy. Knowledge about jaw osteosarcoma in pregnancy can increase healthcare providers' awareness, avoid delays and misdiagnosis and potentially improve maternal and neonatal outcomes.

Response of the periodontal tissues to ß-adrenergic stimulation.

AIMS: Stimulation of ß-adrenergic receptors (ßAR) in osteoblasts by isoproterenol (ISO) was shown to induce Vascular Endothelial Growth Factor (VEGF) and angiogenesis in long bones. We thus aimed to determine the vascular response of mandibular tissues to ßAR stimulation regarding blood vessel formation. MAIN METHODS: Six-week-old wild-type C57BL6 female mice received daily intraperitoneal injections of ISO or phosphate buffered saline (PBS) for 1 month. Hemimandibles and tibias were collected for immunolocalization of endomucin, tyrosine hydroxylase (TH), neuropeptide Y (NPY) and norepinephrine transporter (NET). Moreover, Vegfa, Il-1 ß, Il-6, Adrb2 and Rankl mRNA expression was assessed in mandibles and tibias 2 h after PBS or ISO treatment. KEY FINDINGS: Despite similar sympathetic innervation and Adrb2 expression between mandibular tissues and tibias, with TH and NPY+ nerve fibers distributed around blood vessels, ISO treatment did not increase endomucin+ vessel area or the total number of endomucin+ vessels in any of the regions investigated (alveolar bone, periodontal ligament, and dental pulp). Consistent with these results, the expression of Vegfα, Il-6, Il-1ß, and Rankl in the mandibular molar region did not change following ISO administration. We detected high expression of NET by immunofluorescence in mandible alveolar osteoblasts, osteocytes, and periodontal ligament fibroblasts, in addition to significantly higher Net expression by qPCR compared to the tibia from the same animals. SIGNIFICANCE: These findings indicate a differential response to ßAR agonists between mandibular and tibial tissues, since the angiogenic potential of sympathetic outflow observed in long bones is absent in periodontal tissues.

Oral pyogenic granuloma: An 18-year retrospective clinicopathological and immunohistochemical study.

BACKGROUND: Pyogenic granuloma (PG) is a lesion characterized by the proliferation of blood vessels, commonly affecting the skin and the mouth. We aimed to compare clinical, microscopic, and immunohistochemical features of the two types of oral PG: lobular capillary hemangioma (LCH) and non-LCH (NLCH). METHODS: Epidemiological and clinical data from 2000 to 2018 were collected from the archives of our institution, and histopathological sections of PG were reviewed. Immunohistochemical analyses (CD34, D2-40, SMA, mast cell, and Ki-67) were performed in 34 cases. RESULTS: Sixty-two LCH and 107 non-LCH samples were included. The mean (±SD) age of the patients was 38.59 ± 16.96 years; 55.62% were female; 39.64% of cases occurred in the gingiva, 44% of the nodules were pedunculated, and 13.02% of patients reported a history of trauma. NLCH was more prevalent among older patients than LCH. The most prevalent site of LCH was the lips, while NLCH occurred more in the gingiva (P < 0.05). Epithelial atrophy, microvessels, SMA-positive areas, and Ki-67-positive nuclei were more prevalent in LCH (P < 0.05). CONCLUSIONS: PG accounted for 2.25% of lesions archived in the pathology service and most cases were NLCH. LCH and NLCH exhibited clinicopathological differences in terms of age, site, epithelial atrophy, vascularization, and proliferation rate.

Central Odontogenic Fibroma with the Presence of Large Fibroblasts of Varying Morphology.

A patient with an odontogenic fibroma (OF) with the presence of fibroblasts of varying morphology is presented, and the main microscopic differential diagnosis is discussed. Case report: a 51-year-old man complained of a swelling in the anterior region of the mandible. The panoramic radiograph showed a radiolucent, well-defined multilocular image, with displacement of the roots of the left mandibular incisors and canine. A cone beam computed tomography examination revealed a hypodense image, with delicate bone spicules inside, divergence of the tooth roots and destruction of the buccal cortical bone. Under the differential diagnosis of a desmoplastic ameloblastoma or a squamous odontogenic tumor, an incisional biopsy was made. Microscopically, deeply collagenized tissue with scarce odontogenic epithelium islands, large fibroblasts of varying morphology and calcified material was observed. A diagnosis of OF was made. Surgical removal was carried out, and the specimen was examined. Identical aspects were found, and the immunohistochemical reaction for pan-cytokeratin was carried out to identify the odontogenic epithelial cells. The definitive diagnosis of OF was confirmed, and we emphasize the importance of the correlation of all characteristics for a definitive diagnosis.

Live and heat-killed Lactobacillus reuteri reduce alveolar bone loss on induced periodontitis in rats.

OBJECTIVE: Lactobacillus reuteri is reported as a beneficial adjunct to conventional periodontitis treatment or as monotherapy for gingivitis in several clinical trials. However, probiotics are not free from the risk of adverse effects. We investigated the effects of live and heat-killed (paraprobiotic) L. reuteri during the development of ligature-induced periodontitis in rats. METHODS: Thirty-two male rats were divided into four groups-control group: healthy rats, LIP group: rats with ligature induced periodontitis, LIP/PRO group: rats with periodontitis that received live L. reuteri, LIP/PARA group: rats with periodontitis that received heat-killed L. reuteri. Treatment was administered for 30 days prior to ligation and continued for 14 days until euthanasia. The hemimandibles were removed and submitted to radiographic analysis, microcomputerized microtomography (µCT) and histomorphometric analysis. RESULTS: Radiographic analysis revealed that pro- and paraprobiotics enhanced the percentage of mesial bone support. The µCT analysis showed that paraprobiotic treatment increased bone volume and trabecular number while decreasing total bone porosity and trabecular separation. Live probiotic led to higher trabecular thickness. In the histomorphometric analysis, paraprobiotics significantly prevented furcation bone loss and collagen breakdown, although both pro- and paraprobiotics similarly reduced mesial bone loss. There were no significant differences in attachment loss or the number of tartrate-resistant acid phosphatase -positive cells across treatments. CONCLUSIONS: Although viable and heat-killed bacteria reduced mesial alveolar bone loss and ameliorated furcation microarchitecture parameters, paraprobiotics presented the most pronounced results preventing periodontitis development. This can contribute to the future use of paraprobiotics in the prevention and treatment of periodontitis.