Accuracy of cone-beam computed tomography in determining gingival thickness: a systematic review and meta-analysis.

OBJECTIVE: To assess the accuracy of cone-beam computed tomography (CBCT) for determining gingival thickness. MATERIAL AND METHODS: Searches were undertaken in PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO, and gray literature (Google Scholar and ProQuest) for studies considered eligible according to the following criteria: cross-sectional observational studies, which compared CBCT accuracy with that of transgingival probing when determining gingival thickness, in adult patients with good periodontal health. No language or time restrictions were applied in this systematic review. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for analytical cross-sectional studies. RESULTS: Six articles were included for qualitative synthesis, involving a pooled sample of 132 patients with a mean age of 29 years (18-51 years). Of these 6 studies, 5 were eligible for quantitative analysis. The meta-analysis showed no statistically significant difference between CBCT and transgingival probing measures of gingival tissue (mean difference of 0.10 (95% CI-0.17-0.38). No significant level of heterogeneity was detected (Tau2-P = 0.0662; I2 = 0%; H2-P = 1.000; Q-P = 1.134). According to the GRADE criterion, confidence in the cumulative evidence was considered low. CONCLUSIONS: CBCT is an accurate method for determining gingival tissue thickness, comparable to the reference standard (transgingival probing). CLINICAL RELEVANCE: CBCT could be considered for gingival thickness measurement when bone thickness is also needed, and thereby aid in the assessment of gingival biotype without the discomfort and anesthesia needed in transgingival probing. TRIAL REGISTRATION: This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42022326970. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326970 .

Impact of Fracture Line Width on Radiographic Diagnosis of Vertical Root Fractures: Analysis of the Generalised Estimating Equation Model.

OBJECTIVE: To undertake a joint analysis of the influence of fracture width, dental thickness and distance of the fracture from the cortical bone on the radiographic diagnosis of vertical root fractures. METHODS: Thirty-six uniradicular bovine teeth were endodontically treated and distributed into three groups according to the remaining root dentine thickness: 1.2 mm, 1.5 mm and 1.8 mm. Each group comprised 12 teeth, six with vertical root fracture and six without. Scanning electron microscopy (SEM) images of the fractured tooth groups were obtained and the fracture lines were measured. All specimens were inserted into bone defects created in bovine ribs, at different distances from the external cortical bone. Digital periapical radiographs were randomly evaluated by three blinded examiners (presence or absence of fractures). RESULTS: The specificity for periapical radiography was found to be 89% and the accuracy rate was 57.4%. The mixed-model regression using the generalised estimating equation (GEE) model showed that the width of the fracture line and the thickness of the dental remnant play an important role in radiographic detection of vertical root fractures. There is a lower chance of correct diagnosis with fracture line widths < 0.2 mm (odds ratio [OR] 0.294, 95% confidence interval [CI] 0.103 to 0.836; P = 0.022) and tooth thicknesses < 1.2 mm (OR 0.342, 95% CI 0.157 to 0.747; P = 0.007). CONCLUSION: Fracture line widths < 0.2 mm and smaller root thicknesses lead to a less accurate diagnosis of vertical root fractures on periapical radiographs.

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions.

Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions.

Stem Cell Marker Expression in Persistent Apical Periodontitis.

INTRODUCTION: This study evaluated the expression of CD90 (mesenchymal stem cell) and Sox2 (progenitor stem cell) markers in persistent apical periodontitis (PAP) (n = 16) and primary periapical lesions (PPLs) (n = 10). METHODS: All samples were classified histologically according to the intensity of inflammatory cell infiltrate in the periapical lesion. Immunohistochemistry was used to detect CD90 and Sox2 in PAP and PPLs. The Spearman correlation coefficient and the Mann-Whitney U test were used to analyze data at the 5% significance level. RESULTS: CD90 expression was found in mesenchymal cells and vascular endothelial cells of 68.5% of all cases of PAP. There was no correlation between CD90 expression and histopathological diagnosis (P = .053) or inflammatory cell infiltrate intensity (P = .112). CD90 staining was predominantly found in the vascular endothelial cells of 30% (n = 3) of PPLs. CD90 expression was significantly higher in PAP than in PPLs (Mann-Whitney U test, P < .05). Sox2 expression was found in all cases of PAP. Eventually, all mesenchymal and chronic inflammatory cells exhibited Sox2 expression. There was no correlation between Sox2 expression and histopathological diagnoses (P = .749), inflammatory cell infiltrate intensity (P = .510), or acute or chronic inflammatory cell infiltrate (P = .256). Sox2 expression was found in 100% of PPLs. There was no difference in Sox2 expression between PAP and PPLs (P = .477). CONCLUSIONS: Mesenchymal stem cells may contribute to the immunosuppressive environment in PAP. Additionally, distinct stem cell sources may be associated with the chronic nature of PAP as well as with the development of PPLs.

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions

Abstract Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions.

Osteonecrose dos maxilares associada ao uso de bisfosfonatos: recidiva após radioterapia de cabeça e pescoço / Bisphosphonates osteonecrosis of the jaws: Recurrence after head and neck radiotherapy

O processo natural de remodelação óssea ocorre através de atividadescelulares, mediada principalmente por osteoblastos e osteoclastos.A interrupção desse processo pode levar a ocorrência de alterações como a osteonecrose. A osteonecrose é causada por diversos fatores, dentre eles locais e sistêmicos, destacando-se o uso de medicamentos e radioterapia. A osteonecrose dos maxilares associada ao uso de bisfosfonatos (ONB) é caracterizada pela presença de um osso necrótico exposto na cavidade bucal, por mais de 8 semanas, em pacientes tratados com este medicamento, sem o histórico de terem sido submetidos à radioterapia de cabeça e pescoço. Já osteorradionecrose (ORN), em conseqüência da radioterapia para tratamento de neoplasias malignas, reduz o potencial de vascularização do tecido ósseo, afetando a atividadecelular, a formação de colágeno e a capacidade de reparo do tecido, podendo levar à necrose. A ONB e ONR apresentam como principais sinais e sintomas: dor intensa, edema, parestesia, infecções, ulceração dos tecidos moles e alterações radiográficas. Por apresentarem características semelhantes, clinicamente a diferenciação entre a ONB e ORN se dá apenas pela história de uso ou não de bisfosfonatos. Este trabalho teve como objetivo abordar um caso sem precedentes, em que descreveu-se a recidiva de uma osteonecrose mandibular, após o debridamento cirúrgico e a infusão de PRP, em uma paciente que posteriormente foi submetida à radioterapia de cabeça e pescoço para tratamento de um caso de reincidência de um mieloma múltiplo (MM).

The natural bone remodeling process occurs mediated by osteoblasts and osteoclasts. Disturbances in this process may lead to osseous changes as osteonecrosis. Osteonecrosis is caused by several factors, including local and systemic factors, highlighting the use of drugs or radiation. The Bisphonates related osteonecrosis of the jaw (BRONJ) is characterized by the presence of an exposed necrotic bone in the oral cavity for more than 8 weeks in patients treated with this drug, with no history of being subjected to radiotherapy. Osteoradionecrosis (ORN), as a result of radiotherapy, reduces the vascularization potencial of bone, affectingcellular activity, the collagen formation and the capacity of tissue repair, leading to necrosis. As signs and symptoms of BRONJ and ONR is described: intense pain, edema, paresthesia, infection, ulceration, soft tissue and radiographic changes. Because they have similar characteristics, clinical differentiation between the BRONJ and ORN is given only by the history of bisphosphonates intake. This study aimed to discuss an unprecedented case in which was described an mandibular osteonecrosis relapse, after surgical debridement and the PRP infusion, in a patient who has subsequently submitted to radiotherapy for the treatment of a recurrence of multiple myeloma (MM) in head and neck region.

Ultrastructural and immunohistochemical study of early repair of alveolar sockets after the extraction of molars from alendronate-treated rats.

The aim of the present research was to analyze ultrastructural and immunohistochemical aspects of the alveolar repair after the extraction of molars of alendronate (ALN)-treated rats. Wistar rats received 2.5mg/kg body wt/day of ALN during 14 days previously and 7, 14 and 21 days after the extraction of the second mandibular molar. Specimens were fixed in 2% glutaraldehyde + 2.5% formaldehyde under microwave irradiation, decalcified in 4.13% EDTA and paraffin embedded for TRAP histochemistry and immunohistochemistry for OPN, BSP and endoglin, or embedded in Spurr epoxy resin for TEM analysis. Additional specimens had their soft tissues removed and were processed for scanning electron microscopy. The ALN group presented latent TRAP-positive osteoclasts and nonresorbed alveolar crests with bacterial infection. Mild bone necrosis signs were observed at all time points studied. Ultrastructurally, empty osteocyte lacunae were observed and bone trabeculae surface presented hyalinized aspect. A significant delay in alveolar repair occurred, as well as decreased angiogenesis. ALN treatment provoked mild signs of bone necrosis, despite the high dose employed. The present findings add new information about the ultrastructural aspect of the early repair of rats under ALN treatment and highlight for giving attention when oral surgeries are performed in patients using this drug.