Bacterial cellulose matrix and acellular dermal matrix seeded with fibroblasts grown in platelet-rich plasma supplemented medium, compared to free gingival grafts: a randomized animal study

PURPOSE

Mucogingival defects (MGDs), such as dental root recessions, decreased vestibular depth, and absence of keratinized tissues, are commonly seen in dental clinics. MGDs may result in functional, aesthetic, and hygienic concerns. In these situations, autogenous soft tissue grafts are considered the gold-standard treatment. This study compares the healing process of free gingival grafts (FGGs) to bacterial cellulose matrix (BCM) and human acellular dermal matrix (ADM) seeded with fibroblasts from culture supplemented with platelet-rich plasma in a rat model.

METHODS

Surgical defects were made in rats, which received the following treatments in a randomized manner: group I, negative control (defect creation only); group II, positive control (FGG); group III, BCM; group IV, BCM + fibroblasts; group V, ADM; and group VI, ADM + fibroblasts. Clinical, histological, and immunological analyses were performed 15 days after grafting. Clinical examinations recorded epithelium regularity and the presence of ulcers, erythema, and/or edema.

RESULTS

The histological analysis revealed the degree of reepithelization, width, regularity, and presence of keratin. The Fisher exact statistical test was applied to the results (P<0.05). No groups showed ulcers except for group I. All groups had regular epithelium without erythema and without edema. Histologically, all groups exhibited regular epithelium with keratinization, and myofibroblasts were present in the connective tissue. The groups that received engineered grafts showed similar clinical and histological results to the FGG group.

CONCLUSIONS

Within the limitations of this study, it was concluded that BCM and ADM can be used as cell scaffolds, with ADM yielding the best results. This study supports the use of this technical protocol in humans.

Clinicopathological Features of Metastasis to the Oral and Maxillofacial Region-Multicenter Study

BACKGROUND

This study aimed to investigate the clinicopathological features of metastases in the oral and maxillofacial regions.

METHODS

In this retrospective study, biopsy records were obtained from referral centers for oral and maxillofacial diagnosis in Brazil, Guatemala, Mexico, and South Africa.

RESULTS

A total of 120 cases were evaluated. Of these, 53.78% affected female patients, with a mean age of 57.64 years. Intraosseous lesions were more frequent, particularly in the posterior region of the mandible (49.58%). Clinically, most cases presented with symptomatic swelling, with an average evolution time of 25 months. The clinical diagnostic hypothesis in most instances was that of a malignant lesion. Breast cancer was the most common primary tumor location in females, while lung origin was most common in males. In most cases, the primary cancer was an adenocarcinoma (44.73%). The follow-up period was available for 29 cases, and out of these, 20 had died due to the disease.

CONCLUSION

Although this is a rare condition, clinicians should be aware that any oral lesions have the possibility of being metastatic, particularly in individuals with a previous history of cancer. The findings from this study could assist clinicians in prompt diagnosing these lesions and subsequent conducting oncologic assessments and treatment.

Microvascular density analysis and histological parameters of oral cancer progression

OBJECTIVES

This study aimed to investigate the role of blood and lymphatic microvascular density in the progression of oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

The sample was composed of 54 cases of OSCC. The immunoexpression to anti-alpha-smooth muscle actin (α-SMA) and to anti-endoglin (CD105) was used to determine the microvessel density (MVD); anti-podoplanin (D2-40) was used to assess the lymphatic vessel density (LVD); vascular endothelial growth factor (VEGF) was evaluated in malignant cells. The histological differentiation, the worst pattern of invasion (WPOI), tumour thickness and tumour budding (TB) intensity were assessed using haematoxylin-eosin and anti-pan-cytokeratin (AE1/AE3). Patients' age and sex, TNM classification and follow-up time were collected from the medical records.

RESULTS

MVD markers presented a similar pattern of expression in blood vessels. However, only α-SMA + MVD was significantly higher among women and in tumours ≤4 cm. LVD was lower in tumours with lymph node metastasis. Regarding the histological parameters, high TB intensity was associated with histological differentiation, advanced clinical stage, greater tumour thickness and reduced disease-free survival. No difference was found in VEGF.

CONCLUSIONS

The decrease in OSCC LVD could be related to pathological node involvement, whereas high TB intensity could indicate OSCC progression and worse patient outcomes.

Prevalence of oral and maxillofacial lesions in children and adolescents at a regional Brazilian oral pathology service: a retrospective study and the relevant literature review

PURPOSE

This study assessed the prevalence of maxillofacial lesions in children, i.e., 0-9 years, and adolescents, i.e., 10-19 years, in a Brazilian Oral Pathology Service and compared results with available literature.

METHODS

Clinical and histopathological records from January 2007 to August 2020 were analysed and a literature review investigating maxillofacial lesions in paediatric populations was also performed.

RESULTS

Overall, "reactive salivary gland lesions" and "reactive connective tissue lesions" were the most prevalent group of soft tissue lesions, affecting children and adolescents equally. From these, mucocele and pyogenic granuloma were the most prevalent histological diagnoses, respectively, regardless of age. These findings were consistent with the 32 studies included. Considering intraosseous lesions, "odontogenic cysts" and "periapical inflammatory lesions" were the most prevalent groups, with no relevant differences between age groups, except for the odontogenic keratocyst, which was more prevalent in adolescents. Moreover, several odontogenic tumours, such as ameloblastic fibroma and odontogenic myxoma, were significantly more prevalent in children.

CONCLUSION

Most maxillofacial lesions presented a similar prevalence between children and adolescents. Reactive salivary gland lesions and reactive connective tissue lesions were the prevailing diagnostic categories, regardless of age. Some odontogenic tumours and the odontogenic keratocyst showed significantly different frequencies across these age groups.

Tomographic and Histologic Analysis of Different Socket Sealing Approaches for Alveolar Ridge Preservation: A Randomized Controlled Pilot Clinical Trial

Purpose: To compare different socket sealing approaches for alveolar ridge preservation and assess the dimensional changes and histologic characteristics of soft and hard tissues in a 4- to 6-month period. Material and Methods: A total of 22 patients with indicated single-tooth extraction in the maxillary nonmolar region were eligible for this study. After CBCT scanning and minimally traumatic tooth extraction, the alveolar sockets were filled with demineralized bovine bone mineral with collagen (DBBM-C) in patients from all groups except for those in the control group. Patients were divided into groups for socket sealing as follows: unsealed/spontaneous healing (control; n = 6), collagen matrix (n = 5), collagen membrane (n = 5), and autogenous graft (n = 6). A second CBCT scan was taken 4 to 6 months after extraction, and a trephine biopsy of soft and hard tissues was collected during implant placement. Tomographic dimensional changes were compared between groups. Intragroup tomographic evaluation and histological analysis were also performed. Results: Analysis of dimensional changes did not detect differences between the socket sealing groups (P > .05). In an intragroup evaluation, the height of the buccal bone and cross-sectional area of the alveolar ridge were significantly lower 4 to 6 months after extraction for the control group (P = .031). Histological analysis revealed that the socket sealing approach had no impact on hard and soft tissue formation. Conclusion: The data from the present study suggest that socket sealing with a collagen matrix, a collagen membrane exposed to the oral cavity, or an autogenous punch graft had no difference in the effects on volumetric maintenance and tissue formation in a period of 4 to 6 months.

Comparison of tobacco and alcohol consumption in young and older patients with oral squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVE

To compare the proportion of young (up to 45 years of age) and older (over 45 years of age) oral squamous cell carcinoma (OSCC) patients who report tobacco and alcohol consumption.

METHODS

Observational studies reporting tobacco and alcohol consumption among young and older OSCC patients were selected in a two-phase process. Search strategies were conducted on five main electronic databases and complemented by grey literature. The risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated with the software R Statistics version 4.0.2 (The R Foundation).

RESULTS

From 6675 records identified, 38 studies met the eligibility criteria and were selected for qualitative synthesis and meta-analysis, encompassing 2439 young and 13,393 older patients. Tobacco smoking was reported by 39.5% (confidence interval (CI) = 31.7% to 47.9%, I² = 78%) of the young patients and 48.4% (CI = 37.8% to 59.2%, I² = 94%) of the older patients. Alcohol consumption was reported by 30.9% (CI = 22.7% to 40.5%, I² = 83%) of the young and 45.8% (CI = 35.6% to 56.5%, I² = 95%) of the older patients (P < 0.05).

CONCLUSION

The comparison in the proportion of individuals reporting tobacco and alcohol consumption demonstrated that these habits were more prevalent in the older group (48.4% and 45.8% respectively) than in the young group (39.5% and 30.9%, respectively).

CLINICAL RELEVANCE

As a significant proportion of patients with OSCC reported no habits, novel risk factors for OSCC need to be investigated in further research.

Anticancer effects of putative and validated BH3-mimetic drugs in head and neck squamous cell carcinomas: An overview of current knowledge

The purpose of this review was to summarise available literature concerning the anticancer effects of both putative and validated BH3-mimetics in head and neck squamous cell carcinomas. A literature search was performed and studies assessing malignant cell lines, xenograft models, and/or humans were considered eligible. A total of 501 studies were identified, of which 40 were included. One phase-II clinical trial assessing gossypol (combined with docetaxel) was found. The remaining 39 preclinical studies investigated cell lines and/or xenograft models involving the use of six validated BH3-mimetics (A-1210477, A-1331852, ABT-737, navitoclax, S63845, venetoclax) and six putative BH3-mimetics (ApoG2, gossypol, obatoclax, sabutoclax, TW-37, and YC137). In preclinical settings, most validated BH3-mimetics were capable of inducing apoptosis (in-vitro) and tumour growth inhibition (in-vivo). The majority of putative BH3-mimetics were also capable of inducing cell death, although important off-target effects, such as autophagy induction, were also described. Combinations with conventional anticancer drugs, ionising radiation, or multiple BH3-mimetics generally resulted in enhanced anticancer effects, such as increased sensitivity to apoptotic stimuli, especially considering some cell lines that showed resistance to either treatment alone. In conclusion, although clinical data are still insufficient to evaluate the anticancer effects of BH3-mimetics in head and neck squamous cell carcinomas, promising results in preclinical settings were observed concerning induction of cell death and inhibition of tumour growth. Therefore, further clinical trials are highly encouraged.

Impact of the COVID-19 pandemic on Public University Laboratories of oral and maxillofacial pathology - a Brazilian multicenter study

OBJECTIVE

To evaluate the impact of the COVID-19 pandemic on the number of diagnoses of oral and maxillofacial lesions in public laboratories after one year of COVID-19 outbreak in Brazil.

MATERIAL AND METHODS

This is a cross-sectional study. Biopsies submitted to histopathologic examination from March 2019 to February 2020 (pre-pandemic period) and from April 2020 to March 2021 (pandemic period) in nine Brazilian public oral pathology laboratories were retrieved and the number of diagnoses, types of lesion, and percentage changes during both periods were analyzed.

RESULTS

There were 7,389 diagnoses in the pre-pandemic period and 2,728 in the pandemic era, indicating a reduction of 63.08%. The reduction was 64.23% for benign lesions and 49.48% for malignant lesions, with a 50.64% reduction in squamous cell carcinoma. The largest decreases were observed in April 2020 and January 2021.

CONCLUSION

An important reduction in the diagnoses of benign and malignant lesions was noted in the Brazilian public oral pathology laboratories during the first year of the COVID-19 pandemic.

Persistent pain after successful endodontic treatment in a patient with Wegener’s granulomatosis: a case report

Wegener’s granulomatosis (WG) is a condition with immune-mediated pathogenesis that can present oral manifestations. This report describes the case of a patient diagnosed with WG 14 years previously, who was affected by persistent pain of non-odontogenic origin after successful endodontic treatment. A 39-year-old woman with WG was diagnosed with pulp necrosis and apical periodontitis of teeth #31, #32, and #41, after evaluation through a clinical examination and cone-beam computed tomography (CBCT). At the first appointment, these teeth were subjected to conventional endodontic treatment. At 6- and 12-month follow-up visits, the patient complained of persistent pain associated with the endodontically treated teeth (mainly in tooth #31), despite complete remission of the periapical lesions shown by radiographic and CBCT exams proving the effectiveness of the endodontic treatments, thus indicating a probable diagnostic of persistent pain of non-odontogenic nature. After the surgical procedure was performed to curette the lesion and section 3 mm of the apical third of tooth #31, the histopathological analysis suggested that the painful condition was likely associated with the patient's systemic condition. Based on clinical, radiographic, and histopathological findings, this unusual case report suggests that WG may be related to non-odontogenic persistent pain after successful endodontic treatments.

Prognostic biomarkers for malignant transformation of oral potentially malignant disorders: a scoping review protocol

OBJECTIVE

This scoping review aims to identify and systematically map the available evidence concerning the prognostic biomarkers for malignant transformation of oral potentially malignant disorders (OPMDs), and to identify and analyze possible knowledge gaps in this field of literature.

INTRODUCTION

It is hypothesized that diagnosis and treatment of oral cancer in its early stages may be the key to improving the prognosis and reducing treatment-related consequences. Oral potentially malignant disorders represent tissue alterations with a higher risk of malignant transformation compared to the normal mucosa. Therefore, the study of prognostic biomarkers for OPMD could represent new diagnosis and therapeutic targets and, consequently, contribute to the reduction of oral cancer burden worldwide.

INCLUSION CRITERIA

Longitudinal studies investigating prognostic biomarkers regarding the malignant transformation of OPMD will be included. The initial OPMD diagnosis and the malignant transformation must have been confirmed by histopathological analysis. To achieve minimal heterogeneity, studies that assess biomarkers in other locations (blood, plasma or others) will be excluded.

METHODS

Five electronic databases and three grey literature databases will be consulted. No restrictions regarding publication date will be applied. Only studies published in the Latin (Roman) alphabet, which comprises most of the European languages, will be included. Study selection will be performed by two authors in a two-phase process; if any disagreement arises, a third author will be consulted to make a final decision. Data extraction will be performed by two authors using a standardized extraction tool. The results will be described in details accordantly with the aims of this scoping review.

Prevalence of oral mucosal lesions in patients with pemphigus vulgaris: A systematic review and meta-analysis

OBJECTIVE

To assess the prevalence of oral mucosal lesions in patients with Pemphigus Vulgaris.

METHODS

Observational studies reporting the prevalence of oral lesions in pemphigus vulgaris patients, without restriction to language and year of publication, were selected in a two-phase process. Search strategies were applied to PubMed, Scopus, Livivo, Web of Science, LILACS, Google Scholar, and OpenGrey databases. Articles assessing the prevalence of oral lesions in patients with conditions other than pemphigus vulgaris were excluded. Risk of bias analysis was performed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated by the software R Statistics version 4.0.2 (The R Foundation). Confidence in cumulative evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From 1957 studies identified, 40 were included in qualitative synthesis and 38 in meta-analyses. The pooled prevalence of patients with oral lesions solely or concurrent with other mucocutaneous lesions was 90.3%. The prevalence of patients with exclusive oral mucosal lesions was 50.8%. Risk of bias was considered low, and the certainty of evidence was very low.

CONCLUSION

Oral lesions were present in approximately nine out of 10 patients with pemphigus vulgaris. The oral mucosa was the most common site of disease onset. Further longitudinal studies are urged to assess the prevalence of oral lesions at different disease stages.

Effectiveness of marsupialisation and decompression on the reduction of cystic jaw lesions: a systematic review

In this study, we aimed to systematically review and critically appraise the available literature concerning the effectiveness of marsupialisation and decompression on the reduction of cystic jaw lesions. The 'Preferred Reporting Items for Systematic Reviews and Meta-Analysis' guidelines were followed and the study protocol was registered at the 'International Prospective Register of Systematic Reviews' (CRD42019116099). Six main databases were searched: Embase, LILACS, PubMed, Scopus, The Cochrane Library, and Web of Science. Searches were complemented with three grey literature sources: Google Scholar, ProQuest, and Open Grey. Any reduction measures, compared with preoperative status or other procedures, were considered. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tool. Thirty-one studies were included, of which five were judged with low, 24 with moderate, and two with high risk of bias. Considering surgical approach, 20 studies assessed the decompression and 11 the marsupialisation technique. Most studies considered these techniques as preliminary treatments, followed by enucleation. From 1088 lesions found, most were odontogenic keratocysts (33.8%), followed by unicystic ameloblastomas (21.0%), dentigerous cysts (20.6%), and radicular cysts (8.4%). Large lesions and younger individuals frequently presented more favourable responses to treatment and anatomical location was not associated with lesion reduction overall. The intervention duration generally ranged between one to two years. In conclusion, marsupialisation and decompression were mostly considered as preliminary treatments, followed by enucleation. Lesion reduction was generally considered insufficient for these techniques to be used as definitive therapies, although benefits concerning the diminished invasiveness of the secondary surgery were often proposed.

Prevalence of mucoepidermoid carcinoma among intraoral minor salivary gland tumors: A systematic review and meta-analysis

This study aimed to synthetize and critically appraise available evidence regarding mucoepidermoid carcinoma (MEC) prevalence among intraoral minor salivary gland tumors (MiSGT). Five main electronic databases and three grey literature databases were searched. The risk of bias (RoB) was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Proportion meta-analyses were performed. From 1321 studies identified, 82 were included in qualitative synthesis and 80 in meta-analyses. Sixteen were classified as high, 33 as moderate, and 33 as low RoB. A total of 12 774 MiSGT were found, of which overall MEC prevalence was 16.5% (95% Confidence Interval [95% CI] = 14.8%-18.4%). Most MiSGT were found in the palate (n = 7115), although MEC pooled prevalence in this anatomic location was only 13.6% (95% CI = 11.7%-15.6%). The retromolar area presented the highest pooled prevalence (58.9%; 95% CI = 47.0%-70.3%), followed by gingiva (28.8%; 95% CI = 22.7%-35.4%) and tongue (27.2%; 95% CI = 21.2%-33.6%). Regarding geographic location, Middle East presented the highest pooled prevalence (20.8%; 95% CI = 14.8%-27.6%), followed by America (20.0%, 95% CI = 17.2%-23%) and Europe (15.6%; 95% CI = 9.2%-23.5%). Among MiSGT, the MEC overall prevalence was approximately 16.5%. Although most MiSGT were found in the palate, the retromolar area was proportionally more affected by MEC.

Prognostic and clinicopathological significance of podoplanin immunoexpression in oral and oropharyngeal squamous cell carcinoma: A systematic review

BACKGROUND

Podoplanin (PDPN) is a glycoprotein associated with epithelial-mesenchymal transition, invasion, and metastasis in several types of malignancies, including oral and oropharyngeal squamous cell carcinoma (OSCC). The aim of this systematic review (SR) was to summarize and critically appraise the available evidence about the association between PDPN immunoexpression and clinicopathological features and its utility as a prognostic marker in OSCC.

METHODS

Five electronic databases and three gray literature databases were searched for immunohistochemical studies, which were selected in a two-phase process.

RESULTS

From 721 records identified, 22 cohort and seven analytical cross-sectional studies were included. Few studies reported that PDPN expression was associated with poorer survival rates in OSCC: overall survival = 4/12, disease-free survival = 4/7, and cancer-specific survival = 2/4 studies. Positive associations were most frequently reported on lymph node involvement, higher histopathological grade, and advanced clinical stages.

CONCLUSION

Within limitations of this SR, PDPN may be associated with lymph node involvement, histopathological grade, and clinical stage of OSCC. Current evidence suggests that PDPN could be a useful prognostic marker for OSCC that needs further exploration.

Dystrophic calcification and respiratory metaplasia in the epithelial lining of odontogenic cysts: a study of 362 odontogenic cysts in a Brazilian population and literature review

PURPOSE

Main study: undertake a histological study of odontogenic cysts (OC) to determine the prevalence of dystrophic calcification and metaplasia to respiratory epithelium on a Brazilian population.

LITERATURE REVIEW

to review the literature for studies that investigated the prevalence of respiratory metaplasia and dystrophic calcification on OC.

METHODS

Main study: a retrospective histopathological evaluation was made of the archives from a pathology laboratory. A total of 362 cases diagnosed as OC were identified; they were analyzed by two expert observers to determine the presence of dystrophic calcification and respiratory metaplasia. The association with sex, age and anatomic location was performed through statistical analysis.

LITERATURE REVIEW

a critical literature review was undertaken. Two main electronic databases (PubMed and LILACS) were searched. Retrospective studies of histological evaluation that determined the prevalence of epithelial metaplasia and dystrophic calcification on OC, with at least 10 cases, were included; their findings were summarized and discussed.

RESULTS

Main study: the histological evaluation of OC revealed the presence of respiratory epithelium in 25 cases (6.9%) and dystrophic calcification in 24 cases (6.6%). Positive association was found to dystrophic calcification on residual cyst and age; respiratory metaplasia on OC and sex; respiratory metaplasia on residual cyst and gnatic bone; respiratory metaplasia in OC and gnatic bone; dystrophic calcification in OC and anatomic site of mandible.

LITERATURE REVIEW

eleven studies were included in the literature review, and respiratory metaplasia ranged from 0.0% to 19.2% while dystrophic calcification ranged from 2.5% to 40.5%.

CONCLUSIONS

the histological evaluation of this study found 6.9% of prevalence of respiratory metaplasia and 6.6% of dystrophic calcification, which is in accordance with the literature reviewed. Therefore, these phenomena must be taken into account in routine diagnosis services.

Cell-block as ancillary tool for the diagnosis of cystic and cyst-like jaw lesions

BACKGROUND

The cell-block technique is a cytological diagnostic method that decreases cellular dispersion; however, its usefulness regarding intraosseous lesions is underexplored. Therefore, this study aimed to assess the diagnostic usefulness of cell-block for cystic and cyst-like jaw lesions.

METHODS

Individuals with cystic or cyst-like jaw lesions who underwent aspiration biopsy were considered eligible. Aspiration of luminal content was prepared and processed by the cell-block technique. Cytological evaluations were blindly performed by two trained PhD students (in a single evaluation) and one oral and maxillofacial pathologist (OMP). Cohen's kappa statistic was used to measure inter-rater agreement.

RESULTS

The sample was composed of 52 lesions, represented by 25 radicular cysts (RC), 17 odontogenic keratocysts (OKC), 5 idiopathic bone cavities (IBC), and 5 unicystic ameloblastomas (UA). The kappa coefficient of cell-block compared to histopathological diagnosis was 0.390 (95% confidence interval [95%CI], 0.195-0.585) for PhD students and 0.612 (95%CI, 0.433-0.791) for the OMP. The highest concordance rates between cell-block and histopathological diagnosis were observed for RC (PhD = 76.0%; OMP = 80.0%) and OKC (PhD = 58.8%; OMP = 76.5%). Conflicting results were found regarding IBC (PhD = 40.0%; OMP = 80.0%) and UA, that presented the overall lowest concordance rates (PhD = 20.0%; OMP = 40.0%).

CONCLUSION

The cell-block technique presented a high diagnostic usefulness for detecting RC and OKC and, if associated with clinical and radiographic characteristics, might be sufficient for final diagnosis of these diseases. Regarding IBC and UA, an analysis with a higher number of cases is recommended to determine the true usefulness of the cell-block as ancillary tool for the diagnosis of these lesions.

A Brazilian multicentre study of 2,497 isolated cases of odontogenic keratocysts

We present the frequency of cases of isolated odontogenic keratocysts submitted to microscopic examination at 10 Brazilian referral centres in Oral and Maxillofacial Pathology. In a retrospective (1953-2017) analysis, data on clinicoradiographic features and treatment of these lesions were collected and analysed descriptively. Among the 258,867 cases retrieved, 2,497 (0.96%) were isolated odontogenic keratocysts. In summary, an overview of individuals affected with isolated odontogenic keratocysts is reported herein. This lesion showed predilection for the posterior mandible of young adult men.

Comparative analysis between developmental and inflammatory odontogenic cysts: retrospective study and literature review

PURPOSE

To assess epidemiological, clinical, and radiographic characteristics of odontogenic cysts (OCs) in a South Brazilian sample and to compare the results with international literature.

METHODS

For the main study purposes, biopsy and histopathological records were retrospectively analyzed from December 2006 to December 2018, OC cases were selected, and data about clinical characteristics were evaluated. Further, a literature review was performed for similar studies.

RESULTS

In the main study, the prevalence of OCs was 11.26% (n = 406), the majority of patients was male (56.73%), and the mean age was 39 ± 17.33 years. Radicular cyst was the most common OC (46.06%), followed by the odontogenic keratocyst (15.02%), dentigerous cyst (14.04%), and paradental cyst (13.55%). Inflammatory OCs were more prevalent in the maxilla (54.84%) and developmental cysts in the mandible (69.92%) (p < 0.05). Individuals with inflammatory OCs were usually older (41.0 ± 15.34 years) than the ones with developmental OC (28.0 ± 19.68 years) (p < 0.05). Regarding the literature review, 22 articles were included. Analysis of pooled data showed that global prevalence of OCs was 11.62% (95%CI = 9.97-13.37), from which radicular cyst was the most common (54.26%; 95%CI = 49.30-59.18), followed by dentigerous cyst (22.94%; 95%CI = 19.22-26.89) and odontogenic keratocyst (11.99%; 95%CI = 8.88-15.49). Furthermore, studies from Asia (72.40%; 95%CI = 70.30-74.40) and South America (68.48%; 95%CI = 64.07-72.72) presented the highest frequencies of inflammatory OCs.

CONCLUSION

The main study showed that the prevalence of OCs was 11.26%, which corroborates with international literature. Considering geographic variability of OC distribution, public health authorities and researchers could use these data for the development of focused prevention interventions, especially with regard to inflammatory OCs.

The synergistic effect of tobacco and alcohol consumption on oral squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVES

This systematic review (SR) aimed to summarise and critically appraise available evidence about the association between the synergistic consumption of alcohol and tobacco and the occurrence of oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Observational studies investigating the association between the synergistic consumption of alcohol and tobacco and OSCC occurrence were included. Studies were selected in a two-phase process and searches were conducted on five main electronic databases, complemented by three grey literature databases.

RESULTS

From 3260 records identified, 33 articles were included for qualitative analysis, of which 15 were included in the meta-analyses. Overall, the synergistic consumption was positively associated with the occurrence of OSCC (odds ratio [OR] = 5.37; 95% confidence interval [95%CI] = 3.54-8.14). Increased odds for OSCC occurrence were observed regarding the synergistic consumption of alcohol and smoked tobacco (OR = 4.74; 95%CI = 3.51-6.40), alcohol and smokeless tobacco (OR = 7.78; 95%CI = 2.86-21.14), and alcohol, smoked tobacco, and smokeless tobacco (OR = 16.17; 95%CI = 7.97-32.79).

CONCLUSIONS

According to the results of this SR, the synergistic consumption of alcohol and tobacco (both smoked and smokeless) significantly increased the odds for the occurrence of OSCC.

CLINICAL RELEVANCE

The knowledge provided by this SR may be useful for a better understanding of differences in the effect of synergistic consumption of alcohol and tobacco products in OSCC development. These data might aid healthcare authorities to develop measures for tobacco and alcohol control considering the needs of their population.

Fibrous dysplasia with secondary aneurysmal bone cyst-a rare case report and literature review

INTRODUCTION

Fibrous dysplasia (FD) and aneurysmal bone cyst (ABC) are uncommon non-neoplastic intraosseous lesions, and the occurrence of concomitant FD and ABC is extremely rare.

CASE REPORT

An 11-year-old boy presented with gradual progressive enlargement of his right zygomatic bone over 4 years prior to presentation. Computed tomography revealed a lesion with a central bony area showing a ground-glass appearance surrounded by a well-defined expansile lesion with internal septations. An incisional biopsy was performed and suggested a fibro-osseous lesion. Resection was performed, followed by immediate reconstruction using autogenous bone graft from the iliac crest. Histopathological examination revealed irregularly shaped trabeculae comprising immature woven bone in a fibroblastic cell-rich stroma. Blood-filled sinusoidal spaces lined by fibrous septa containing scattered multinucleated giant cells were observed peripherally. These findings were compatible with concomitant FD and ABC. The patient was disease-free at the time of his 10-month follow-up.

CONCLUSIONS

Based on our literature search, this report is the first to describe concomitant monostotic FD and ABC in the zygomatic bone. Accurate diagnosis requires careful investigation and examination of clinical, radiographical, and histopathological features. The treatment of choice should provide an esthetic and functional improvement in the patient.

Inhibition of cancer stem cells promoted by Pimozide

Over the past years, studies have described that users of antipsychotics are less likely to develop cancer than the population in general due to cytotoxic properties of this class of drugs on cancer cells. For this reason, Pimozide has been widely studied as a potential anticancer treatment, and satisfactory results in melanoma, central nervous system tumours, osteosarcoma, neuroblastoma, myeloproliferative neoplasms, breast, lung, prostate, ovarian, colorectal, pancreatic, and hepatocellular carcinoma have been showed. Moreover, advantages as clinical use approved by the Food and Drug Administration (FDA), high clinical safety, low side effects, and reasonable price have stimulated the treatment with Pimozide instead of other agents. The action mechanism remains unclear, but three vias associated to cancer stem cell (CSC) hypothesis show that Pimozide: (a) blocks CSC features, as epithelial-to-mesenchymal transition (EMT), through inhibition of Wnt-β/catenin signalling; (b) acts as an inhibitor of signal transducer and activator of transcription (STAT-3 and 5), pathway which is activated and up-regulated in CSCs; (c) inhibits ubiquitine specific protease (USP1) and WD repeat-containing protein 48 (WDR48), that are proteins responsible to inhibit the differentiation and to maintain the cell in an undifferentiated state. Based on this perspective, the aim of this manuscript is to review the antineoplastic role of Pimozide during tumorigenesis and its potential to revert the process of undifferentiation and proliferation of CSC through different vias.

Maté consumption association with upper aerodigestive tract cancers: A systematic review and meta-analysis

Maté is a beverage regularly consumed by Latin American populations. Upper aerodigestive tract (UADT) cancers are frequent in this region and are suspected to be associated with maté consumption. The aim of this systematic review and meta-analysis was to answer a focused question: "Is there an association between maté consumption and occurrence of the UADT cancer?". Studies investigating any association between maté consumption and occurrence of UADT cancer were included. Out of the 569 studies, 18 met the inclusion criteria for qualitative and 15 for quantitative analysis. An increased odds was observed regarding maté consumption and overall occurrence of UADT cancer (OR = 2.24; 95%CI = 1.74-2.87). Consistent evidence of a positive association was found for all UADT subsites, oral, pharynx, esophagus and larynx. No differences in effect were found between consumption of cold/warm and hot/very hot mate (OR = 1.08; 95%CI = 0.83-1.41). Consumption of more than one liter of maté per day was associated with increased odds of having UADT cancer compared to an intake of less than one liter per day (OR = 1.72; 95%CI = 1.47-2.01). According to published data, regardless of the temperature, maté consumption significantly increased the odds of occurrence of UADT cancer.

Prevalence of oral potentially malignant disorders: A systematic review and meta-analysis

Oral potentially malignant disorders (OPMD) are chronic conditions, which have a higher risk of transformation to oral squamous cell carcinoma. The aim of this systematic review and meta-analysis was to answer the question: "What is the prevalence of oral potentially malignant disorders among adults?" Studies reporting the prevalence of these conditions (leukoplakia, erythroplakia, oral submucous fibrosis [OSMF], and actinic cheilitis) were selected, only studies in which a clinical assessment and histopathological confirmation were performed were included. Of the 5513 studies, 22 met the inclusion criteria for qualitative and quantitative analyses. The risk of bias (RoB) of the selected studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Seven studies were classified as high risk, 12 as moderate risk, and 3 as low RoB. The meta-analysis showed that the prevalence of OPMD was 4.47% (95% CI = 2.43-7.08). The most prevalent OPMDs were OSMF (4.96%; 95% CI = 2.28-8.62) and leukoplakia (4.11%; 95% CI = 1.98-6.97). OPMDs were identified more commonly in males (59.99%; 95% CI = 41.27-77.30). Asian and South American/Caribbean populations had the highest prevalence rates of 10.54% (95% CI = 4.60-18.55) and 3.93% (95% CI = 2.43-5.77), respectively. The overall prevalence of OPMD worldwide was 4.47%, and males were more frequently affected by these disorders. The prevalence of OPMD differs between populations; therefore, further population-based studies may contribute to the better understanding of these differences.

The Role of the Complex USP1/WDR48 in Differentiation and Proliferation Processes in Cancer Stem Cells

BACKGROUND

Recently, some studies identified the Basic-Helix-Loop-Helix (bHLH) transcription factor as a significant regulator for the evolution of neoplasms. The binding between bHLH proteins and DNA is restricted by heterodimerization with Inhibitors of DNA binding (ID). IDs prevent cellular differentiation, promote growth and sustain tumor development. The wide presence of stem cells in cancers suggests that genes ID are essential to cancer stem cells (CSC) progress. The enzyme Ubiquitin-specific protease 1 (USP1) is reported to deubiquitinate and stabilize IDs. Considering the action of the proteins ID, USP1 contributes to prevent differentiation mediated by bHLH and, consequently, keep CSC original characteristics. USP1 has its activity potentiated when bound to protein WD repeat-containing protein (WDR48).

OBJECTIVE

To identify the influence of the complex USP1/WDR48 during the CSC tumorigenesis process, and whether this complex is a possible therapeutic target.

METHODS

A literature search regarding the role of the complex USP1/WDR48 in inhibiting differentiation and increasing proliferation of CSC was performed, and possible selective molecule inhibitors of these deubiquitinase proteins were investigated.

RESULTS

There is evidence that USP1/WDR48 complex promotes stem cell conservation and regulation of DNA damage repair. For this reason, inhibitors as Pimozide, GW7647, C527, SJB2-043, ML323 have been studied to inhibit USPs in cases of treatment intervention.

CONCLUSION

It is consolidated in the literature the role of USP1/WDR48 during tumorigenesis. However, these studies are not enough to completely clarify the process; but certainly, the researchers are converging towards a promising direction to provide a new treatment option for cancer.

Evaluation of Mandibular Bone After Dental Extraction in Rats Treated With Antiresorptive Drugs

PURPOSE

Zoledronic acid (ZOL) and denosumab (Dmab) are commonly used to treat bone pathologies. Because these drugs suppress bone metabolism, this study sought to compare their effect on bone repair after tooth extraction.

MATERIALS AND METHODS

Four-week-old male Wistar rats were randomly assigned to 1 of 3 groups: ZOL 0.125 mg/kg, Dmab 0.25 mg/kg, or saline solution 10 mL/kg (control). After 1 week of treatment, the first left molar was extracted; the rats were euthanized at 28 days. The jaws were removed and photographed for macroscopic analysis of wound healing and then subjected to tomographic and histologic analyses. Immunohistochemistry was carried out against the receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG).

RESULTS

No difference in wound healing, presence of inflammatory infiltrate and bone sequestration, or osteocyte expression of RANKL and OPG was found among groups. Tomographic analysis showed that the ZOL group had less alveolar resorption and more complete alveolar repair compared with the other groups. There was a statistically significant difference in the OPG marker in the control (P = .008) and ZOL (P = .05) groups when comparing the extracted and non-extracted sides.

CONCLUSION

Systemic use of ZOL can improve alveolar bone healing; however, the potential risk for the development of osteonecrosis should be considered. Higher expression of OPG seems to be associated with the control of osteoclastogenesis during bone repair.

Tissue integrity, costs and time associated with different agents for histological bone preparation

The selection of an appropriate demineralizing solution in pathology laboratories depends on several factors such as the preservation of cellularity, urgency of diagnostic and financial costs. The aim of this study was to test different decalcification bone procedures in order to establish the best value of these in formalin-fixed and paraffin-embedded samples. Femurs were removed from 13 adult male Wistar rats to obtain 130 bone disks randomly divided into five groups that were demineralized in different concentrations of nitric acid (Group I); formic acid (Group II); acetic acid (Group III); EDTA, pH7.4 (Group IV) and Morsés solution (Group V). Serial, 3-μm-thick sections were obtained and stained with hematoxylin-eosin to calculate the percentage of osteocyte-occupied lacunae. The sections were also stained with Masson's trichrome in conjunction with picrosirius red under polarized light followed by a semi-quantitative analysis to verify the adjacent muscle-to-bone integrity and preservation of collagen fibres. The highest percentage of osteocyte-occupied lacunae was found with 10% acetic acid solution (95.64 ± 0.95%) and Group I (nitric acid) demanded the shorter time (0.8-5.7days). Of all solutions, 5% nitric acid incurred the lowest cost to achieve complete demineralization compared with other solutions (p < .001). Group IV (EDTA) had the highest integrity of muscle and collagen type I and III (P < 0.01). Demineralization with 10% acetic acid was the most effective at preserving bone tissue, while 5% EDTA was the best at maintaining collagen and adjacent muscle to bone. In conclusion, nitric acid at 5% showed the most efficient result as it balanced both time and cost as a demineralizing solution.

Myositis Ossificans of the Temporalis Muscle

Traumatic myositis ossificans (TMO) is a rare ossifying disease that occurs in the muscle or soft tissues. A case of TMO isolated in the temporalis muscle is reported. In the case described, calcification in the temporalis muscle was confirmed after computed tomography. Surgery, physiotherapy, and histopathological analysis were performed. One year after treatment, further ossification was present but without interference in function. The most accepted treatment for TMO in the maxillofacial region is excision followed by physiotherapy. The high rate of non-recurrence may be concealed due to the short follow-up period. TMO is a lesion that may frequently recur and long-term follow-up must be provided.

A Rare Case of Mucoepidermoid Carcinoma ex Pleomorphic Adenoma arising in Minor Salivary Gland: Histopathological and Immunohistochemical Analysis

Mucoepidermoid carcinoma ex pleomorphic adenoma (MCxPA) is a rare salivary gland tumor predominantly found in major salivary glands. A case of MCxPA involving the soft tissue and bone of the retromolar region of a 26-year-old man is presented. The histopathological features revealed a neoplasm with predominance of pleomorphic adenoma (PA) elements, and presence of mucoepidermoid carcinoma malignant epithelial cells in several areas. Histochemical and immunohistochemical studies were positive for periodic acid Schiff, alcian blue, cytokeratins 7, 13, 14, and 19, Bcl-2, c-erbB-2, FGF-2 and maspin in the malignant areas. The patient underwent a partial resection of the left side of the mandible with neck dissection and MCxPA diagnosis was confirmed.

Incidência de anormalidades histológicas em tecido correspondente ao espaço pericoronário de terceiros molares inclusos e semi-inclusos

INTRODUÇÃO: O Folículo Pericoronário envolve a coroa do germe dental durante seu desenvolvimento. Quando o dente permanece incluso, alterações do folículo podem originar doenças, como cistos e tumores odontogênicos. OBJETIVO: Analisar as alterações histológicas no tecido mole circundante a terceiros molares inclusos e semi-inclusos, independentemente de alterações patológicas aparentes em suas radiografias correspondentes, além de relacionar o diagnóstico histológico com o diagnóstico radiográfico dos casos. MATERIAL E MÉTODO: A partir de terceiros molares extraídos de 26 pacientes, foram analisados espécimes histológicos de folículos pericoronários por dois examinadores calibrados. O diagnóstico histopatológico obtido foi relacionado ao radiográfico, sendo este realizado por meio de radiografias periapicais e, quando necessário, complementado por radiografias panorâmicas. RESULTADO: Dos 37 folículos pericoronários avaliados, 30% mostraram alterações histológicas compatíveis com cistos dentígeros; 51% eram folículos normais, e 19% continham apenas fragmentos de mucosa. Radiograficamente, 100% dos casos demonstraram características de folículos sem alterações. CONCLUSÃO: Esses dados exemplificam que anormalidades podem estar presentes nos tecidos pericoronários sem que haja evidências clínicas e radiográficas. O exame histopatológico provê um diagnóstico mais preciso e deve ser considerado para a construção do diagnóstico definitivo.

Avaliação do metabolismo epitelial em cistos radiculares pela técnica de AgNORS

Introdução: A formação do Cisto Radicular (CR) está associada à proliferação dos restos epiteliais de Malassez por estímulos inflamatórios, provenientes da proliferação bacteriana do canal radicular de um dente não vital. Quando o dente é removido, esse cisto passa a ser denominado Cisto Residual (CRe). O tratamento de escolha para o CR é endodôntico, com o objetivo de eliminar a inflamação presente no periápice. No entanto, em alguns casos, o cisto pode continuar a crescer, necessitando de tratamento cirúrgico, o que ocorre na maioria dos casos de CRe. Objetivo: Avaliar o metabolismo do epitélio de revestimento de CR e CRe, utilizando a quantificação das AgNORs, e verificar a influência da presença de inflamação sobre o crescimento desses cistos. Material e método: Vinte casos de CR e dez de CRe foram submetidos à técnica de AgNOR. A análise quantitativa das NORs foi realizada utilizando-se o software 'Contando células'. O teste estatístico pós-hock de Newman-keuls foi realizado para a comparação do número médio de AgNORs entre CR e CRe, e entre áreas inflamadas e não inflamadas. Resultado: Diferença estatisticamente significante (p=0,0094) foi observada entre áreas inflamadas (1,86±0,26) e não inflamadas (1,65±0,20). Na comparação entre CR (1,81±0,28) e CRe (1,73±0,16), não houve diferença estatisticamente significante (p=0,37). Conclusão: A inflamação interfere no metabolismo epitelial de CR e CRe, o que reflete a ação de fatores de crescimento na proliferação do epitélio, contribuindo para o crescimento do cisto, independentemente da presença do fator etiológico associado com a origem da lesão.

Cell block technique as a complementary method in the clinical diagnosis of cyst-like lesions of the jaw

OBJECTIVE

To evaluate the applicability of the cell block technique as a complementary method for presumptive diagnosis in the analysis of cyst-like aspirates from jaw lesions prior to histopathological diagnosis.

MATERIAL AND METHODS

The sample was made up of 17 cyst-like jaw lesions. After puncture, the aspirates were centrifuged, fixed in formalin, embedded in paraffin and processed. All lesions were biopsied and submitted to histopathological examination.

RESULTS

In 9 cases, the cytopathological analysis using the cell block method showed a predominant presence of erythrocytes, inflammatory cells and few epithelial cells. In the other 8 cases, the cell block technique demonstrated the presence of parakeratin, whose histopathological analysis confirmed the occurrence of keratocystic odontogenic tumors (KOTs).

CONCLUSIONS

According to the studied cases, the cell block method was proven to be a simple, fast and low-cost technique to effectively differentiate KOTs from other lesions with similar clinical and radiographic features. The cell block technique comprises cellular preparations useful to determine a clinical diagnosis and help to develop a therapeutic plan for those lesions.

Techniques for precancerous lesion diagnosis

The development of the oral squamous cell carcinoma (OSCC) is a multistep process that requires the accumulation of multiple genetic alterations usually preceded by detectable mucosal changes, most often leukoplakias and erythroplakias. The clinical appearance of oral precancerous lesions and their degree of epithelium dysplasia suggests the malignization potential. Several techniques have been developed to improve the clinical and cytological diagnosis of oral precancerous lesions. The present paper reviews the main techniques used to improve premalignant lesion diagnosis.

Immunohistochemical expression of DNA methyltransferases 1, 3a and 3b in oral leukoplakias and squamous cell carcinomas

Over-expression of DNA methyltransferases DNMT1, DNMT3a and DNMT3b has been reported in various cancers and precancerous lesions.

OBJECTIVE

To investigate DNMT1, DNMT3a and DNMT3b enzymes in oral squamous cell carcinoma (SCC) and leukoplakia, and their relationship with histopathologic/clinical parameters.

STUDY DESIGN

Immunohistochemistry was carried out to evaluate the three DNMTs in 60 samples of oral SCC and 37 samples of oral leukoplakia.

RESULTS

DNMT3a immunoreactivity in the three groups of oral SCC (39.8%) was significantly higher than in control (22.6%) (ANOVA, Student-Newman-Keuls test, P<0.05), but not when compared to oral leukoplakia groups (28.2%). For DNMT1 and DNMT3b, there were no statistically significant differences between oral SCC groups (65% and 74.7%), oral leukoplakia groups (68.3% and 70.9%) and control (65.4% and 76.5%). There was a significantly higher mean percentage of DNMT1 immunoreactivity in non-smokers (ANOVA, P=0.048), and a higher DNMT3a immunoreactivity in alcohol users (ANOVA, P=0.01).

CONCLUSIONS

Higher DNMT3a immunopositivity may be associated with oral SCC and alcohol use, whilst lower levels of DNMT1 may be related with smoking habit. However, there was a significantly higher mean percentage of DNMT1 immunoreactivity in non-smokers (ANOVA, P=0.048), and a higher DNMT3a immunoreactivity in alcohol users (ANOVA, P=0.010).