Deep Learning-Based Microscopic Diagnosis of Odontogenic Keratocysts and Non-Keratocysts in Haematoxylin and Eosin-Stained Incisional Biopsies

Background: The goal of the study was to create a histopathology image classification automation system that could identify odontogenic keratocysts in hematoxylin and eosin-stained jaw cyst sections. Methods: From 54 odontogenic keratocysts, 23 dentigerous cysts, and 20 radicular cysts, about 2657 microscopic pictures with 400× magnification were obtained. The images were annotated by a pathologist and categorized into epithelium, cystic lumen, and stroma of keratocysts and non-keratocysts. Preprocessing was performed in two steps; the first is data augmentation, as the Deep Learning techniques (DLT) improve their performance with increased data size. Secondly, the epithelial region was selected as the region of interest. Results: Four experiments were conducted using the DLT. In the first, a pre-trained VGG16 was employed to classify after-image augmentation. In the second, DenseNet-169 was implemented for image classification on the augmented images. In the third, DenseNet-169 was trained on the two-step preprocessed images. In the last experiment, two and three results were averaged to obtain an accuracy of 93% on OKC and non-OKC images. Conclusions: The proposed algorithm may fit into the automation system of OKC and non-OKC diagnosis. Utmost care was taken in the manual process of image acquisition (minimum 28–30 images/slide at 40× magnification covering the entire stretch of epithelium and stromal component). Further, there is scope to improve the accuracy rate and make it human bias free by using a whole slide imaging scanner for image acquisition from slides.

Unicystic Ameloblastoma of Mandible: A Case Report

Ameloblastoma is a neoplasm that originates from odontogenic epithelium. It is the second most common neoplasm of the oral cavity. Unicystic ameloblastomas refer to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst, but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/ or mural growth. Even though the lesion is not that aggressive as the solid ameloblastoma, an accurate diagnosis should be made. This lesion needs to be treated more aggressively than any other periapical lesions.

Can Vitamin D Therapy Contribute to the Conservative Resolution of Osteolytic Lesions of the Jaws?

Osteolytic lesions of the jaw are not uncommon. Such lesions usually arise from local pathologies, but some have systemic backgrounds. We describe a 12-year-old girl who presented with an asymptomatic left mandibular swelling. The bony swelling was corresponding to a radiolucent lesion in the left premolar/molar region. This lesion could have represented an inflammatory and developmental odontogenic jaw cyst, giant cell lesion, and odontogenic tumor. However, the workup investigations revealed secondary hyperparathyroidism due to vitamin D deficiency. A vitamin D replacement was initiated with a single I.M. injection of 300,000 I.U followed by 10,000 I.U orally, weekly. Six weeks later, her Vitamin D and parathyroid hormone were normalized, and she showed significant clinical and radiological improvement of the jaw lesion. At 18 months, follow-up the panoramic image revealed complete resolution of the radiolucency and stable normal parathyroid hormone and vitamin D levels. In conclusion, Jaw bone lesions can develop secondary to hyperparathyroidism due to vitamin D deficiency, and this should be ruled out before any surgical intervention. Treatment of such lesions lies in the correction of parathyroid excess with a careful and systematic approach. This may prevent unnecessary surgical intervention in such patients.

Minimally Invasive Technique for Removal of a Mandibular Radicular Cyst : A Case Report

The removal of an odontogenic jaw cyst usually requires at least elevation of the mucoperiosteal flap for adequate access to the cystic lesion and its complete enucleation. In this report, we present a simple intra-socket flapless cystic removal technique for a radicular cystic lesion related to the mandibular first molar. This technique produces an optimal outcome and gives the patient the most comfortable surgical experience.

A volumetric prediction model for postoperative cyst shrinkage

Objectives With only limited information available on dimensional changes after jaw cyst surgery, postoperative cyst shrinkage remains largely unpredictable. We aimed to propose a model for volumetric shrinkage based on time elapsed since cyst surgery. Material and methods We used data from patients that underwent cyst enucleation or decompression between 2007 and 2017 and had at least three computed tomography (CT) scans per patient. We fitted one simple exponential decay model [V(t) = V0 · e−ɑt] and one model with a patient-specific decay rate [Vk(t) = V0 · e−βt + γkt]. Results Based on 108 CT scans from 36 patients (median age at surgery: 45.5 years, IQR: 32.3–55.3, 44% female), our simple exponential decay model is V(t) = V0· e−0.0035t where V(t) is the residual cyst volume after time t elapsed since surgery, V0 is the initial cyst volume, and e is the base of the natural logarithm. Considering a patient-specific decay rate, the model is Vk(t) = V0· e−0.0049t + γkt where γk is normally distributed, with expectation 0 and standard deviation 0.0041. Conclusions Using an exponential regression model, we were able to reliably estimate volumetric shrinkage after jaw cyst surgery. The patient-specific decay rate substantially improved the fit of the model, whereas adding specific covariates as interaction effects to model the decay rate did not provide any significant improvement. Clinical relevance Estimating postoperative cyst shrinkage is relevant for both treatment planning of jaw cyst surgery as well as evaluating the clinical success of the surgical approach.

Preservation the Pulp Activity of the Involved Teeth in Jaw Cyst: an Observational Study

Background: Jaw cyst is the most common disease of the oral and maxillofacial region. In addition to the pathogenic tooth, the roots of some teeth are often located in the cavity of the cystic capsule. Whether these involved teeth require root canal therapy and apicoectomy is still inconclusive. In the present study, we aimed to preserve the pulp activity of involved teeth in jaw cyst by improved operation.Methods: In our improved surgical method, the root canal therapy was not performed on the involved teeth, and no apical excision was performed during the operation. 63 involved teeth in 20 cases of jaw cyst treated by our department were selected between September 2015 and October 2017. The involved teeth were diagnosed by X-ray, CBCT, and a pulp vitality test before surgery. We observed the pulps' activity in the involved teeth and the efficacy of surgery for 12-36 months.Results: Electrical activity test of 63 involved teeth pulp in 20 patients with jaw cyst was normal or insensitively before operation. The involved teeth were preserved by improved surgical method. After 12-36 months’ follow-up, the pulp activity of 53 involved teeth (84.1%) were preserved, whereas 10 teeth (15.9%) showed adverse symptoms such as redness and swelling in the apical area, fistula, and pain. These symptoms resolved after postoperative root canal therapy. Chewing function was restored well. There was no recurrence and the bone cavity gradually reduced and finally disappeared, and bone density returned to normal after long term follow-up.Conclusion: Our results showed that to preserve the activity of the involved teeth for the treatment of jaw cyst by performing an improved operation method was effective.

Unique case of glandular odontogenic cyst showing mucoepidermoid carcinoma-like islands in cystic wall

Glandular odontogenic cyst (GOC) is a very rare jaw cyst accounting for 0.2% of all odontogenic cysts. It presents usually in adults with a slight male predominance. It shows radiological, histopathological and even immunohistochemical overlap with low grade intraosseous mucoepidermoid carcinoma (MEC) but their distinction is crucial. A 57-year-old woman with bilocular radiolucency in the anterior mandible crossing the midline is described here. Microscopy features were consistent with glandular odontogenic cyst but multiple MEC-like islands were seen in the capsule, creating a diagnostic head trip with low grade intraosseous MEC. However, the absence of cellular atypia and epidermoid and intermediate cells led to a final diagnosis of GOC, with close follow-up of the patient recommended. This rare finding shows the relation between GOC and MEC or the origin of MEC from GOC.

Post-Operative Outcomes of Radiological and Histopathological Findings after Hydroxyapatite and Allogenic Bone Graft among Jaw Cyst Patients: A Randomized Clinical Trial

Background: Post-surgical outcomes of jaw cyst is very crucial. Objective: The purpose of the present study was to observe the radiological and histological finings as postoperative outcomes after hydroxyapatite and allogenic bone graft among jaw cyst patients. Methodology: This single centre, parallel, randomized clinical trial was conducted in the Department of Oral and Maxillofacial Surgery at Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from July 2006 to June 2008 for a period of two (02) years. Patients presented with radicular and dentigerous cyst with the size of the lesion between 2 cm to 7 cm. in diameter and relatively non infected cystic lesion were selected as study population. The study population were divided into two groups designed as group A treated with hydroxyapatite alloplastic material and group B treated with allogenic-bone graft after enucleation of the cystic lesion. The standard surgical procedure was to be performed meticulously in sterile environment. Post-operative radiograph were taken after one month, three months and six months. Histopathological examination was done after six month of operation which was done in the department of Pathology, BSMMU. Scintigraphic examination was performed after 6 months of the operation to evaluate the viability of the bone graft in the graft site. Result: A total number of 28 patients were recruited for this study of which 14 patients were treated with hydroxyapatite crystals bone graft in group A and 14 patients were treated with allogenic bone graft in group B. The age of patients of both groups ranged between 14 and 58 years. In histopathological examination marked presence of cementing line, woven bone and osteoblast cell was found in patients who were grafted with hydroxyaptite and this had indicated good osteoblastic activity. Increased technetium-99m labeled diphosphonate uptake was found in the patient with allograft. There was a smaller lesion diameter of hydroxyapatite group in comparison with allogenic bone graft group which had indicated comparatively better healing than that of the hydroxyapatite group. Conclusion: In conclusion hydroxyapatite alloplastic material has better radiological and histopathological outcomes than allogenic bone graft after surgery of jaw cyst. Journal of National Institute of Neurosciences Bangladesh, 2020;6(1): 48-53

Clinico-Radiological assessment of Unicystic Ameloblastoma of mandible – a case report

Ameloblastoma is a most common benign odontogenic tumour. It is slow growing but aggressive tumour which causes destruction of jaw bones. Clinically it is asymptomatic and can be noticed when the tumour increases gradually in size and causes facial asymmetry or detected during dental radiographic procedures for evaluating the missing or impacted teeth, especially third molar. Unicystic ameloblastomas account for 10-15 % of all intraosseous ameloblastomas. Here we discuss a case report of unicystic ameloblastoma with its clinical and radiological features along with emphasizing the three-dimensional imaging assessment of the case. Key words Ameloblastoma, jaw cyst, Odontogenic tumor, adamantinoma