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 7389 diagnoses in the pre-pandemic period and 2728 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.

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.

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.

A multicentre study of oral paracoccidioidomycosis: Analysis of 320 cases and literature review.

OBJECTIVES: To investigate the frequency of oral paracoccidioidomycosis from representative geographical regions of Brazil and to compare the data with a literature review. MATERIALS AND METHODS: A retrospective study was conducted on 108,304 biopsies obtained from 1953 to 2016 at six Brazilian oral and maxillofacial pathology services. Demographic data and clinical and histopathological diagnosis of oral paracoccidioidomycosis were evaluated. A literature review of oral paracoccidioidomycosis studies published in three electronic databases was carried out. Data were analysed descriptively. RESULTS: A total of 320 cases of oral paracoccidioidomycosis were surveyed (0.3% of the oral lesions at the centres studied). The lesions were more frequent among male patients. The gingiva/alveolar ridge was the most affected site. Mean age of affected individuals was 51.3 years (±11.7). The literature review showed a higher incidence of oral paracoccidioidomycosis in the south-east and south regions of Brazil. Male individuals and individuals between 50 and 59 years were most affected. CONCLUSIONS: Oral paracoccidioidomycosis is an uncommon lesion observed in oral biopsy samples. The differences in the relative frequency of oral paracoccidioidomycosis are related to geographical variations. Men between 50 and 59 years are more affected. This study provides helpful information for clinicians in the diagnosis of oral paracoccidioidomycosis.

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.

Immunohistochemical expression of matrix metalloproteinases in ameloblastomas and pericoronal follicles.

BACKGROUND: Ameloblastoma (AM) is a benign odontogenic neoplasm characterized by local invasiveness and recurrence. We compared the immunohistochemical expression of matrix metalloproteinases in different clinical types of AM as well as in normal odontogenic tissue. METHODS: Thirteen cases of solid AMs, five cases of unicystic AM and eight pericoronal follicles (PF) were selected and subjected to immunohistochemical investigation for matrix metalloproteinase-1, matrix metalloproteinase-2 and matrix metalloproteinase-9 expressions. RESULTS: The expressions of MMP-1 and MMP-2 were very high in the cytoplasm of cells throughout the entire epithelium and in fibroblasts from the adjacent connective tissue. MMP-9 expression was observed in the same location although with weaker staining. The Kruskal-Wallis test showed statistically significant differences in the epithelial expressions of MMP-1 and MMP-2; there was lower expression among solid AMs when compared with unicystic AM and PF. Compared to both types of AM, higher stromal expression of MMP-9 was found in PF. CONCLUSION: MMP-1, MMP-2 and MMP-9 seem to be associated with AM tumour behaviour as well as physiological tissue remodelling within PF.

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.

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.

Pharmacological therapy for central giant cell granuloma of the jaws: A systematic review.

Background: Pharmacological therapy has been used as an alternative or complementary approach to surgery in central giant cell granuloma (CGCG) of the jaws. This systematic review examined the effectiveness of pharmacological therapy for CGCG of the jaws, focusing on clinical outcomes. Material and Methods: Electronic searches were performed in six databases. Case reports and/or cases series were included. The Kaplan-Meier survival analysis method was used to evaluate outcomes related to clinical resolution and recurrence. The risk of bias was assessed using the Joanna Briggs Institute tool. Results: A total of 74 studies comprising 205 cases of CGCG were included. About 65.4% of cases occurred in individuals under 20 years of age. Most of the treated patients were women (61%) and the mandible (72.2%) was the most reported site. Curettage and enucleation before or after pharmacological therapy were reported in 28.3% and 19% of cases, respectively. The main pharmacological agent used was triamcinolone (37.5%). Complete resolution of CGCG was reported at a rate of 77.1%, while side effects were experienced by 9.8% of individuals. The recurrence rate was 6.8%. Conclusions: Pharmacological therapy may be an effective and safe option for managing CGCG, especially in the young population. Although the overall success rate in achieving complete resolution is encouraging, further controlled studies are needed to refine drug selection and protocols. Key words:Calcitonin, Central giant cell lesion, Denosumab, Interferon, Pharmacological therapy, Triamcinolone.

Association between epithelial-mesenchymal transition markers, proliferative index, and oral epithelial dysplasia: an immunohistochemical study.

OBJECTIVE: This study aimed to correlate the immunoexpression of epithelial-mesenchymal transition markers, vimentin and E-cadherin (E-CAD), and putative markers, podoplanin (PDPN) and osteopontin (OTPN), with the expression of interleukin (IL-6), P53, and Ki-67, and with clinical and histologic parameters of oral epithelial dysplasia (ED). STUDY DESIGN: Immunohistochemical reactions were performed in 61 cases of leukoplakia with ED, graded as low-risk (LRED = 38) and high-risk (HRED = 23) for malignant transformation. Odds ratios (OR) and 95% CI were calculated using logistic regression analysis. RESULTS: High-risk epithelial dysplasia was more frequently observed in non-homogeneous leukoplakia (OR:7.66; CI:1.43-41.04), lesions on the tongue/floor of the mouth (OR:3.37; 95% CI:1.14-9.94), and intense PDPN expression (OR:9.17; CI:1.0-83.77). High-risk epithelial dysplasia exhibited higher Ki-67 expression than LRED (P = .013). Non-continuous PDPN was more likely to exhibit extensive loss of E-CAD than continuous PDPN expression (OR:5.81; CI:1.18-28.55). Intense OTPN was more likely to exhibit intense IL-6 than mild/moderate OTPN expression (OR: 8.06, 95% CI: 1.33-48.85). P53 expression was higher in the intense IL-6 group than in the mild/moderate expression group (P = .021). CONCLUSIONS: Our data support the potential of PDPN as a biomarker for malignant transformation owing to its association with HRED and loss of E-CAD expression. Additionally, we demonstrated a possible shared regulatory mechanism between IL-6 and OTPN expression.

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.

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.

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.

Diagnostic performance of periapical and panoramic radiography and cone beam computed tomography for detection of circumferential gaps simulating osseointegration failure around dental implants: A systematic review.

OBJECTIVE: The objective of this study was to appraise the diagnostic performance of periapical (PR) and panoramic (PANO) radiographs and cone beam computed tomography (CBCT) in detecting artificial circumferential gaps simulating osseointegration failure around dental implants in ex vivo studies. STUDY DESIGN: Seven electronic databases and three gray literature sources were searched. Studies reporting diagnostic performance measures or data allowing calculation of those measures compared with the reference standard of in situ direct measurements were considered eligible. Either the area under the receiver operating characteristic curve or accuracy was chosen to summarize findings, with diagnostic performance interpreted as poor, acceptable, excellent, or outstanding. Risk of bias (RoB) was also assessed. RESULTS: The ten included studies mostly suggested overall excellent to outstanding diagnostic capability with PR and CBCT. Various enhancement filters, CBCT voxel sizes, and/or fields of view were associated with acceptable to outstanding efficacy. PANO had the poorest results, with most research demonstrating acceptable to excellent discrimination. The RoB was high for seven studies, moderate for two, and low for -one. CONCLUSIONS: PR and CBCT images were generally superior to PANO for the detection of artificial bone gaps. Results should be interpreted with caution because most studies had a high RoB.

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.

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.

Actinic cheilitis and lip squamous cell carcinoma: Literature review and new data from Brazil.

BACKGROUND: To investigate the prevalence of malignant and potentially malignant lesions of the lip in an oral pathology service and to compare these data with a literature review. MATERIAL AND METHODS: A total of 3173 biopsy reports and histopathological records were analyzed. Cases with a histological diagnosis of actinic cheilitis (AC) with or without epithelial dysplasia, in situ carcinoma, or lip squamous cell carcinoma (LSCC) were included. A comprehensive literature review was conducted to investigate the prevalence of AC and/or LSCC. RESULTS: 124 cases (3.91%) were included, 75 (60.5%) had some degree of epithelial dysplasia and 31 (25.0%) were LSCC. Clinically, most of the lesions were diagnosed as AC (50.8%); however, eight cases clinically reported as AC were histologically diagnosed as LSCC. Regarding clinical characteristics, most individuals were fair-skinned male, with mean age of 54.3±12.3 years, and with a history of long-term solar exposure. Furthermore, 18 articles were selected from the literature, showing that the lower lip was predominantly affected and that most individuals were males, fair-skinned, and older than 40 years. CONCLUSIONS: Since most of the cases diagnosed clinically as AC presented some degree of epithelial dysplasia, it is important to emphasize the value of biopsy and the histological evaluation of this lesion. Key words:Actinic cheilitis, Precancerous conditions, In situ carcinoma, Oral diagnosis, Mouth neoplasms.

Incidence of reactive hyperplastic lesions in the oral cavity: a 10 year retrospective study in Santa Catarina, Brazil.

INTRODUCTION: Reactive hyperplastic lesions develop in response to a chronic injury simulating an exuberant tissue repair response. They represent some of the most common oral lesions including inflammatory fibrous hyperplasia, oral pyogenic granuloma, giant cell fibroma, peripheral ossifying fibroma, and peripheral giant cell lesions. OBJECTIVE: The incidence of those lesions was investigated in an oral pathology service, and the clinical characteristics, associated etiological factors, concordance between the clinical and histopathological diagnostic was determined. METHODS: A total of 2400 patient records were screened from 2006 to 2016. Clinical features were recorded from biopsy reports and patients' files. RESULTS: A total of 534 cases of reactive hyperplastic lesions were retrieved and retrospectively studied, representing 22.25% of all diagnoses. The most frequent lesion was inflammatory fibrous hyperplasia (72.09%), followed by oral pyogenic granuloma (11.79%), giant cell fibroma (7.30%), peripheral ossifying fibroma (5.24%), and peripheral giant cell lesions (3.55%). Females were predominantly affected (74.19%), the gingiva and alveolar ridge were the predominant anatomical site (32.89%), and chronic traumatism was presented as the main etiological factor. The age widely ranges from the 1st decade of life to the 7th. Clinically, the reactive hyperplastic lesions consisted of small lesions (0.5-2cm) and shared a strong likeness in color to the oral mucosa. The concordance between the clinical and histopathological diagnostic was high (82.5%). CONCLUSION: Reactive hyperplastic lesions had a high incidence among oral pathologies. The understanding of their clinical features helps to achieve a clearer clinical and etiological diagnosis, and the knowledge of factors related to their development. This may contribute to adequate treatment and positive prognosis.

Prevalence of odontogenic cysts and tumors associated with impacted third molars: A systematic review and meta-analysis.

PURPOSE: This systematic review aimed to investigate the prevalence of odontogenic cysts and tumors associated with impacted third molars (ITM). METHODS: Only studies that performed histopathological diagnosis of lesions were eligible for inclusion. Five main electronic and three grey literature databases were searched. Risk of bias (RoB) of included articles was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. RESULTS: From 1,300 studies identified, 16 met the inclusion criteria. Seven studies were classified as high, seven as moderate, and two as low RoB. The prevalence of odontogenic cysts and tumors associated with ITM was 5.3% (95%CI: 3.1%-8.1%) of ITM. Odontogenic cysts in particular were found in 4.4% (95%CI: 2.5-6.8%) of the extracted ITM, whilst odontogenic tumors in 0.5% (95%CI: 0.2-0.9%). The dentigerous cyst was mentioned in eleven studies with a pooled prevalence of 2.1% (95%CI: 1.4-3.1%). The odontogenic keratocyst was cited by nine studies and had a prevalence of 0.5% (95%CI: 0.2-0.7%). The radicular cyst was mentioned only in three articles and the pooled prevalence was 4.7% (95%CI: 0.0-19.4%) CONCLUSION: Odontogenic cysts and tumors were found in 5.3% of ITM extracted. The most common lesions were the radicular cyst, dentigerous cyst, and odontogenic keratocyst.