Charge-symmetric and -asymmetric fragmentation dynamics of argon dimers in slow Ar8+-Ar2 collisions.

We present an experimental study of multiple-electron capture-induced fragmentation dynamics of Ar2m+ (4 ≤m≤ 7) dimer ions in 4 keV/u Ar8+-Ar2 collisions. The fragment recoil ion pairs and the charge-changing projectiles are coincidentally measured using a double coincidence technique. The branching ratios between the different charge-sharing fragmentation channels show an inherent enhancement of the asymmetric channels. The kinetic energy release (KER) distributions for the associated electron capture process show a shift in the mean KER values toward the higher side with increasing capture stabilization. The interplay between the different projectile autoionization processes sheds light on the energy depositions to the system during collisions. The Coulomb potential energy curves give a physical insight into the role of the projectile final states in the dimer fragmentation dynamics. The dimer-axis orientation-dependent cross sections for the asymmetric fragmentation channels reveal a forward-backward asymmetry that arises from the geometry of the collision system. Our findings thus give insight into the impact parameter-controlled fragmentation dynamics of multiply charged Ar2m+ dimer ions in highly charged ion-dimer slow collisions.

Human Urinary Metabolomics as Biomarkers in Tobacco Users: A Systematic Review.

Aim: Urine as a biofluid has been rarely used as a diagnostic fluid in oral diseases. The article aims to systematically review the utility of human urinary carcinogen metabolites as an approach for obtaining important information about tobacco and cancer. Materials and Methods: The following article reviews the use of urine and its metabolites as biomarkers in various lesions of the oral cavity including oral squamous cell carcinoma and as a screening method in evaluating tobacco and its components. A bibliographic comprehensive search was carried out in the main databases: PUBMED, SciELO, Google Scholar, VHL, and LILACS for articles that were published from 1985 to 2020. The inclusion criteria were "urinary metabolites," "oral cancer/HNSCC," "body fluids," "tobacco," and "metabolomics." A total of 55 articles were collected which included laboratory studies, systematic reviews, and literature of urinary metabolites in tobacco users. Results: Most of the studies carried out show accurate results with high sensitivity of urinary metabolite biomarkers in individuals with tobacco-based habits and lesions caused by them. Conclusion: The review indicates that urinary metabolite analysis demonstrates its applicability for the diagnosis and prognosis of disease. Urine is a remarkable and useful biofluid for routine testing and provides an excellent resource for the discovery of novel biomarkers, with an advantage over tissue biopsy samples due to the ease and less invasive nature of collection.

Assessment of neurovascular channels in lateral maxillary sinus wall using cone-beam computed tomography: An imperative clinicians guide for implant placements.

Background: The aim of this study is to evaluate the location and radio morphometric features of the posterior superior alveolar artery (PSAA) in patients undergoing rehabilitation of posterior maxilla and other sinus augmentation surgical procedures by cone-beam computed tomography (CBCT). Materials and Methods: A total of 816 CBCT scans were included. Various radio morphometric measurements were done to assess the PSAA location, diameter, and distances to the sinus floor and alveolar crest. Results: The PSAA was mostly intraosseous in the maximum in the age group 31-51 years (56%), in males (53.4%), and in dentate patients (57.4%). The artery tends to be wider in older patients. Distances to the sinus floor or the alveolar crest tend to be shorter in women. Conclusions: This study suggests that CBCT is a valuable pre-surgical tool and the evaluation of the PSAA on CBCT images could reduce the likelihood of excess bleeding during surgery in the maxillary posterior region.

Reliability of Grayscale Value for Bone Density Determination in Oral Rehabilitation using Dental Implants.

Introduction: Quality and quantity of jaw bones have been previously classified in literature using different methods. Imaging modalities such as computed tomography (CT), successfully determine bone density of jaws. This study aims to establish the role of cone-beam CT (CBCT) in determining the density of cortical and cancellous bones at different jaw sites. Materials and Methods: Eighty-three possible implant sites in healthy patients were evaluated using NewTomGiano CBCT machine. Cross-sections were obtained and cortical and cancellous bone densities on different aspects of the virtual implant in terms of Hounsfield unit (HU) were determined using New Net Technologies software version 6.1 and were classified according to software from D1 to D4. Data were entered into SPSS software (version 19.0) and were statistically analyzed. Results: The mean HU showed the highest value for cortical and cancellous in the anterior mandible (mean HU 1874.01 and 1131.73, respectively) followed by the posterior mandible (mean HU 1789.20 and 872.95, respectively) and least in posterior maxilla (mean HU 1068.26 and 830.04, respectively). Maximum D1 bone type was found in cortical bone and D2 bone type was noted in cancellous bone area. Males showed very highly significant cortical bone thickness (P < 0.001) whereas females showed more cancellous bone thickness but the results were nonsignificant. Conclusion: A high degree of concordance between different regions of jaw bones with a strong correlation between the four bone types was obtained. Bone density plays a pivotal role in determining the prognosis of the implant. CBCT has proven to be beneficial in bone density analysis.

Development of a cold target recoil ion momentum spectrometer and a projectile charge state analyzer setup to study electron transfer processes in highly charged ion-atom/molecule collisions.

We report the development and performance of a cold target recoil ion momentum spectrometer (COLTRIMS) setup at TIFR, which is built to study various atomic and molecular processes involving the interaction of slow, highly charged ions from an electron cyclotron resonance based ion accelerator. We give a detailed description of the experimental setup, as well as report some initial results on the electron-capture process in collisions of Ar8+ ions with helium and carbon monoxide targets. Here, we present the longitudinal momentum transfer and the sub-shell resolved Q-value spectrum in the case of 2, 4, and 6 keV/u Ar8+ beams in collision with helium. A longitudinal momentum resolution of 0.27 a.u. is achieved in the present system. We also report the state-selective scattering angle distributions for all the collision systems under investigation. We further discuss the fragmentation of the CO2+ molecular ions for different electron capture channels for the 5 keV/u Ar8+ beam. The combination of the COLTRIMS, along with the beam cleaner, the electrostatic deflectors, and the charge state analyzer, is shown to have certain advantages.

Evaluation of neurovascular anatomical variation in the anterior mandible in North Indian population: A CBCT assessment.

Introduction: The purpose of this retrospective study was to determine the visibility, location and other morphometric features of lingual foramina on CBCT along with its age wise and gender wise correlation. Material and methods: A total of 250 patients were included in the study. Cross-sectional CBCT images of the mandible in the midline were used to locate and define each detected lingual foramen and canal. Descriptive statistics including tables and graphs were used. Genderwise and Age wise correlations were analyzed using Chi-square tests. Results: The number, direction, length, diameter, distance from alveolar crest and inferior borders of mandible were evaluated. Genderwise Lingual foramen was most frequently located in the mandibular midline, above genial tubercle (81.7%). Agewise it was found to be significant (p = 0.019). Genderwise length of canal was found to be significant (p = 0.022). Genderwise diameter of canal at midpoint was found to be very highly significant (p < 0.001) and at innermost point was found to significant. (p = 0.037) Genderwise and Agewise distance between orifice of canal and alveolar crest was found to be very highly significant. (p < 0.001) Genderwise and Agewise distance between innermost point of canal and alveolar crest was found to be highly significant (p = 0.001) and very highly significant (p < 0.001) respectively. Conclusion: Clinicians may consider CBCT for procedures with a risk of hemorrhagic and neurosensory complications such as dental implant placement in the anterior mandible.

A novel approach in diagnosing multiple dentigerous cysts using CBCT illustration indicative of Mucopolysaccharidosis VI - a case report.

Mucopolysaccharidosis VI is a genetic disorder affecting multiple organs with sundry clinical presentations. The main etiological factor reflects the disturbances in mucopolysaccharide metabolism leading to deposition of acid mucopolysaccharide in various tissues. The pathognomonic features of the disease include a large head, short neck, corneal opacity, open mouth associated with an enlarged tongue, enlargement of the skull, and long anteroposterior dimension with unerupted dentition, dentigerous cyst-like follicles, condylar defects, and gingival hyperplasia. An 18-year-old boy with Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI) is described in this article, emphasizing the oral manifestations and radiographic illustration of lesions in the jaws. It also emphasizes the essential role of cone-beam computed tomography to identify and analyze multicentric pathologies in the jaws.

Significance of Morphometric and Anatomic Variations of Nasopalatine Canal on Cone-Beam Computed Tomography in Anterior Functional Zone - A Retrospective Study.

INTRODUCTION: Oral rehabilitation in maxillary anterior region has increased concerns in the dental fraternity to have detailed morphological examination in treatment planning. The nasopalatine canal (NPC) along with its contents plays an important role in determining the prognosis of implants and their associated surgeries. The present study was performed to evaluate morphometric anatomic variations of the NPC using focused small field of view on cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The study included 250 participants. CBCT examination was conducted using standard exposure and patient positioning protocols. Sagittal, coronal, and axial sections were reviewed to determine NPC morphology and dimensions. RESULTS: Single, round, incisive foramen with mean mesiodistal diameter of 3.23 (±1.00) mm, and mean anteroposterior dimension of 3.03 (±0.96) mm was found. Single Stenson's foramen along with funnel shaped, slanted NPC with mean angulation of 81.97 (±42.19), and mean length of 12.67 (±2.69) mm was found. Mean mesiodistal diameter at nasal fossa of NPC was 3.27 (±1.75) mm, at mid-level was 2.23 (±1.02) mm, at palate was 3.46 (±1.12) mm. At least one additional foramen was found. DISCUSSION: Anatomy of the NPC is highly variable. Age-wise and gender-wise correlations revealed statistically significant results for different parameters. The present study highlighted significance of NPC along with its variations. Therefore, a methodical three-dimensional presurgical assessment is mandatory before any surgical intervention in this region.

Cone-beam computed tomography assessment of bone using grayscale values in patients with diabetes mellitus. A case-control observational study.

BACKGROUND: The density of cortical and cancellous bone is a key reason for implant anchorage which might be severely affected during diabetes. AIM: The aim of the study was to establish the role of cone-beam computed tomography (CBCT) using grayscale values in determining bone density in different jaw sites and in comparing the values in healthy with diabetic patients. MATERIALS AND METHODS: Bone densities in 322 possible implant sites in healthy and diabetic patients were evaluated using NewTomGiano CBCT machine. Cross-sections obtained were assessed for bone densities in terms of Hounsfield Unit on different sites using New Net Technologies software version 6.1. STATISTICAL ANALYSIS: Data were statistically analyzed using SPSS software (version 19.0). RESULTS: Age-wise cortical and cancellous bone densities were compared and no statistical significance was obtained. Gender-wise bone density was compared and significant results were found in males. Jaw-wise bone density was compared and was found to be significantly high in the mandible. The mean cortical bone density in control group was 1608.572 (±380.36), whereas in diabetic group was 1395.368 (±296.97), and the mean cancellous bone density in control was 906.918 (±185.40) and in diabetic was 559.868 (±128.16). Teeth wise in cortical bone significant values were found at premolar region (P = 0.046) and in cancellous bone significant values were found at canine and premolar region (P = 0.012) and highly significant values were found at molar region (P = 0.001). CONCLUSION: CBCT unveils a distinct pattern of cortical and cancellous bone density. A high degree of concordance between different regions of the mouth in cortical and cancellous bones was obtained in different study groups. CBCT could be used for bone density analysis.

Hybrid Ameloblastoma of Anterior Maxilla: A Rare and Puzzling Pathologic entity - Case Report with Systematic Review.

Hybrid ameloblastoma has a variable clinical, radiological, and histopathological presentation. They contain two or more different histologic types and their biologic comportment is still arguable. We herein present a case of a hybrid variant of desmoplastic ameloblastoma which is the first of its kind to have ever been reported due to its unusual location in the maxillary anterior region, along with systematic review of clinicopathologic features of reported cases immunohistochemical markers may act as an adjunct in the accurate diagnosis of these lesions.

Palatal Mucormycosis Masquerading as Bacterial and Fungal Osteomyelitis: A Rare Case Report.

Mucormycosis is an acute, fulminating, fungal disease that frequently involves oral, cranial, and facial structures. It is an opportunistic fatal infection which occurs in debilitating and immunosuppressive states. This report documents a rare case of localized maxillary mucormycosis in a patient with uncontrolled diabetes, with emphasis on early and prompt diagnosis of the same.

Functional role of apoptosis in oral diseases: An update.

Cell death appears to be a basic biological phenomenon which is maintained by the human body. The term apoptosis, also known as programmed cell death, is characterized by several unique morphological and biochemical features. Apoptosis and its different forms are essential for tissue homeostasis. Alteration in molecular mechanisms involved in apoptotic signaling contributes to a vast range of oral diseases. An understanding of the regulation of apoptosis has led to the development of many therapeutic approaches and better management of oral diseases. The review updates us the correlation between apoptosis in normal oral tissues and oral diseases.

Diagnostic efficacy of color Doppler ultrasound in evaluation of cervical lymphadenopathy.

BACKGROUND: To evaluate the efficacy of color Doppler ultrasound (CDUS) in differentiating benign and malignant cervical lymph nodes by detecting differences in blood flow patterns. MATERIALS AND METHODS: In this cross-sectional prospective study, 25 untreated patients with clinical evidence of cervical lymphadenopathy were evaluated. CDUS was performed for 80 cervical lymph nodes. The gray scale parameters of the lymph node and intranodal perfusion sites were the key CDUS features used to differentiate between reactive and metastatic lymph nodes. Histopathological confirmations were obtained and compared with the results of CDUS. RESULTS: Initially, 53 cervical lymph nodes were evaluated by clinical examination. Twenty-seven additional lymph nodes (53 + 27 = 80) were discovered by CDUS evaluation. Gray scale parameters for lymph nodes such as size of lymph node, shape of lymph node, and presence or absence of hilum revealed highly significant results (P < 0.0001). Color Doppler flow signals revealed that central/hilar flow was characteristic for benign nodes whereas peripheral/mixed flow was characteristic for malignant nodes, the findings were highly significant (P < 0.0001). Gray scale and color Doppler features are used to differentiate benign and malignant nodes. CONCLUSION: Within the limitations of this study, CDUS evaluation was found to be highly significant with a high sensitivity and specificity over clinical evaluation CDUS examination provides a prospect to reduce the need for biopsy/fine needle aspiration cytology in reactive nodes.

Management of myofascial pain by therapeutic ultrasound and transcutaneous electrical nerve stimulation: A comparative study.

OBJECTIVE: The present comparative study was aimed to determine the effectiveness of Th US and TENS in the management of myofascial pain in TMD patients. MATERIALS AND METHODS: The present randomized comparative study was on 90 patients who were further assigned in three different groups each having 30 patients; Group I was healthy control patients, Group II was receiving Th US therapy, and Group III was receiving TENS therapy. All the 90 patients were further evaluated for maximum inter incisor subjective evaluation regarding muscle pain, impediment to daily life, massage impression on visual analog scale (VAS) scale, and intensity and duration used in Th US massage. RESULTS: The masseter muscle thickness in control group was 12.00 (standard deviation [SD] ±1.1) mm when compared with TMD patient of 13.00 (SD ± 1.1) mm before treatment. Statistical significant findings on VAS score of muscle pain, impediment to daily life, and massage impression were observed in Th US. After treatment, the anechoic areas disappeared or were reduced in Th US group by 95.6% and in TENS by 74.4%. CONCLUSION: Th US appeared to be subjectively better which was related to VAS score of massage impression, muscle pain, and impediment to daily life after treatment as well as sonographically related to existence of anechoic areas.

Computed Tomography in Diagnosis of Admantinoma.

CONTEXT: Admantinoma is second most common benign odontogenic tumor which clinically appears as an aggressive odontogenic tumor, often asymptomatic and slow growing, associated with symptoms such as swelling, dental malocclusion, pain, and paresthesia of the affected area. The radiographic appearance may vary from unilocular to multilocular radiolucencies, imparting a characteristic honey comb, soap bubble appearance or may resemble a caricature of spider. CASE REPORT: This report highlights the importance of conventional and advanced imaging in the diagnosis of large and invasive lesions. Patient reported with complaint of swelling in jaw, which progressively increased; and was found to be bony hard, both intra- and extraorally. Radiographs revealed large multilocular radiolucency on left body and ramus of mandible with soap bubble pattern and knife edged root resorption. Computed tomographic examination evaluated the extent of the lesion, internal structure, and relation to adjacent structures; further a reconstructed image was obtained to evaluate extent of destruction in three dimensions. CONCLUSION: Computed tomography has an important role in the diagnosis and treatment planning is imperative as it is superior in revealing the cortical destruction and extension into the neighboring soft tissues than conventional radiography.

A recoil ion momentum spectrometer for molecular and atomic fragmentation studies.

We report the development and performance studies of a newly built recoil ion momentum spectrometer for the study of atomic and molecular fragmentation dynamics in gas phase upon the impact of charged particles and photons. The present design is a two-stage Wiley-McLaren type spectrometer which satisfies both time and velocity focusing conditions and is capable of measuring singly charged ionic fragments up-to 13 eV in all directions. An electrostatic lens has been introduced in order to achieve velocity imaging. Effects of the lens on time-of-flight as well as on the position have been investigated in detail, both, by simulation and in experiment. We have used 120 keV proton beam on molecular nitrogen gas target. Complete momentum distributions and kinetic energy release distributions have been derived from the measured position and time-of-flight spectra. Along with this, the kinetic energy release spectra of fragmentation of doubly ionized nitrogen molecule upon various projectile impacts are presented.

Dentinogenic ghost cell tumor - a neoplastic variety of calcifying odontogenic cyst: case presentation and review.

CONTEXT: The calcifying odontogenic cyst (COC), also referred to as calcifying ghost cell odontogenic cyst (CGCOC) is a heterogeneous lesion existing either as cystic or solid variant. Due to the fact that all CGCOC lesions are not cystic, and the biological behavior is often not consistent with a cyst, there has always been a controversy as to whether COC is a cyst or a tumor. The dentinogenic ghost-cell tumor (DGCT), a solid variant of the COC, is an uncommon odontogenic neoplasm occurring predominantly in later life. Case report is followed by a concise review and disambiguation of controversial terminologies regarding nomenclature of COC. CASE REPORT: We report a case of 33-year-old female patient who presented with an insidious, steadily increasing swelling on the left side of her face since 8 months. Patient reported slight difficulty in eating because of reduced intraoral space and an obvious concern with facial disfigurement. There was no contributory dental or medical history. Intraorally, a hard, well defined, bicortical swelling was noted in left maxillary region with slight mobility of the associated teeth and normal appearing overlying mucosa. A provisional diagnosis of adenomatoid odontogenic tumor was made, and orthopantomogram, paranasal sinus radiograph and computed tomograpy scan of the face were acquired. A radiographic diagnosis of COC was made, which was subsequently confirmed on histopathology postenucleation of the tumor mass. COC has been seen to be of extensive diversity in its clinical and histopathological features as well as in its biological behavior. CONCLUSION: The present case of 33-year-old female was diagnosed as DGCT, a tumorous form of COC, due to its characteristic histological features; numerous ghost cells and dentinoid material.

Eagle's syndrome veiling as pain of odontogenic origin: Report of two cases with cone beam computed tomography illustration.

Eagle's syndrome, also known as an elongated styloid process, is a condition that may be the source of craniofacial and cervical pain. It is infrequently reported but is probably more common than generally considered. The symptoms related to Eagle's syndrome can be confused with those attributed to a wide variety of facial neuralgia and or oral, dental, and temporomandibular joint diseases. In this paper, there are two cases, which reported to the Department of Oral Medicine, Diagnosis, and Maxillofacial Radiology, with a chief complaint of radiating pain in the preauricular region of the face. After radiographic investigation, these cases are considered as a case of Eagle's syndrome because of increase in the size of the styloid process.

Unilateral segmental odontomaxillary dysplasia: a rare entity of 3 cases and review.

Segmental odontomaxillary dysplasia (SOD) is an uncommon, nonhereditary, rare developmental disorder primarily involving the posterior part of the maxilla and related dental components. It is a rare condition of uncertain etiology that results in painless unilateral expansion of the posterior dentoalveolar complex, gingival hyperplasia, lack of one or both premolars in the affected area, delayed eruption of adjacent teeth and malformations of the primary molars. Radiographically, the affected bone is thickened and irregular in outline, with a coarse trabecular pattern that is vertically oriented resulting in a relatively radioopaque granular appearance. The treatment is focused on extraction of the involved teeth, while in some milder cases the teeth may be retained for a long period. The treatment plan should be based on the degree of involvement as well as the functional and esthetic needs in each case. Considering the rarity of the condition, we report three cases of SOD with variable presentations in a 45-year-old, 24-year-old and 23-year-old individual.