Dental Implant Placement in Medically Compromised Patients: A Literature Review.

As a discipline of dentistry, oral implantology deals with the diagnosis, design, insertion, restoration, and/or management of alloplastic or autogenous oral structures for the purpose of regaining contour, function, aesthetics, and speech in a partially or completely edentulous patient. The present review aims to provide the currently available knowledge about the impact of certain systemic disorders and the usage of some medications on the survival rate of dental implant therapy and to highlight the importance of patient management under these conditions. Diabetes, osteoporosis, cardiovascular diseases, and the intake of some medications can increase the risk of the failure of a dental implant. Even though there are relatively few medical contraindications to dental implant treatment, certain conditions may increase the risk of failure or complications.

Carotid Artery Stenosis on Panoramic Radiographs and CT Scans in Patients With Malignancies After Radiotherapy.

BACKGROUND/AIM: This study aimed to identify the progression of carotid artery stenosis (CAS) in patients with head and neck cancer following radiation therapy (RT) by characterizing associated risk factors. PATIENTS AND METHODS: Panoramic radiographs (OPG), computed tomography (CT) scans, cone-beam CT (CBCT) scans, and ultrasonography (US) of 69 patients with head and neck tumors were selected and analyzed to identify the presence of CAS. Data on tumor location, smoking status, hypertension (HTN), hyperlipidemia (HLD), diabetes mellitus (DM), and treatment were collected from the patients' medical records. Patients who received chemotherapy or no treatment were excluded from the study. The differential diagnosis of other radiopacities and anatomical landmarks were excluded. Patients were divided into two groups: those with CAS (group1) and those without CAS (group 2) and their clinical information was compared. RESULTS: The overall prevalence of CAS on the panoramic radiographs was 16%. Of the 69 patients, 44 underwent radiography before and after radiotherapy, only seven had mild CAS on radiographs after radiotherapy, and no significant difference in CAS was identified before and after radiotherapy. There were also no differences between the groups regarding age, sex, smoking, hypertension, diabetes mellitus, hyperlipidemia, tumor location, and RT dose before and after radiation (p>0.05). CONCLUSION: Radiotherapy does not seem to affect the prevalence of CAS, although it has been identified in some patients after radiotherapy completion.

Predicting Chronic Hyperplastic Candidiasis Retro-Angular Mucosa Using Machine Learning.

Chronic hyperplastic candidiasis (CHC) presents a distinctive and relatively rare form of oral candidal infection characterized by the presence of white or white-red patches on the oral mucosa. Often mistaken for leukoplakia or erythroleukoplakia due to their appearance, these lesions display nonhomogeneous textures featuring combinations of white and red hyperplastic or nodular surfaces. Predominant locations for such lesions include the tongue, retro-angular mucosa, and buccal mucosa. This paper aims to investigate the potential influence of specific anatomical locations, retro-angular mucosa, on the development and occurrence of CHC. By examining the relationship between risk factors, we present an approach based on machine learning (ML) to predict the location of CHC occurrence. In this way, we employ Gradient Boosting Regression (GBR) to classify CHC lesion locations based on important risk factors. This estimator can serve both research and diagnostic purposes effectively. The findings underscore that the proposed ML technique can be used to predict the occurrence of CHC in retro-angular mucosa compared to other locations. The results also show a high rate of accuracy in predicting lesion locations. Performance assessment relies on Mean Squared Error (MSE), Root Mean Squared Error (RMSE), R-squared (R2), and Mean Absolute Error (MAE), consistently revealing favorable results that underscore the robustness and dependability of our classification method. Our research contributes valuable insights to the field, enhancing diagnostic accuracy and informing treatment strategies.

Clinical Experience with Autofluorescence Guided Oral Squamous Cell Carcinoma Surgery.

In our study, the effect of the use of autofluorescence (Visually Enhanced Lesion Scope-VELscope) on increasing the success rate of surgical treatment in oral squamous carcinoma (OSCC) was investigated. Our hypothesis was tested on a group of 122 patients suffering from OSCC, randomized into a study and a control group enrolled in our study after meeting the inclusion criteria. The preoperative checkup via VELscope, accompanied by the marking of the range of a loss of fluorescence in the study group, was performed before the surgery. We developed a unique mucosal tattoo marking technique for this purpose. The histopathological results after surgical treatment, i.e., the margin status, were then compared. In the study group, we achieved pathological free margin (pFM) in 55 patients, pathological close margin (pCM) in 6 cases, and we encountered no cases of pathological positive margin (pPM) in the mucosal layer. In comparison, the control group results revealed pPM in 7 cases, pCM in 14 cases, and pFM in 40 of all cases in the mucosal layer. This study demonstrated that preoperative autofluorescence assessment of the mucosal surroundings of OSCC increased the ability to achieve pFM resection 4.8 times in terms of lateral margins.

Biomechanical Analysis of Palateless Splinted and Unsplinted Maxillary Implant-Supported Overdentures: A Three-Dimensional Finite Element Analysis.

The objective of this study was to compare the distribution of stress in the maxillary bone, dental implants, and prosthetic components supporting implant-supported maxillary overdentures with partial palatal coverage, in both splinted and unsplinted designs. Two models of maxillary overdentures were designed using the Exocad Dental CAD program, which included cancellous and cortical bone. The complete denture design and abutments (locator abutments in the unsplinted and Hader bar with Vertix attachments placed distally in the splinted variant) were also designed. The denture material was PEEK (Polyetheretherketone), and the method used to analyze patient-specific 3D X-ray scans was 3D QCT/FEA (three-dimensional quantitative computed tomography-based finite element analysis). Loading was divided into three load cases, in the frontal region (both incisors of the denture) and distal region (both molars and first premolar of the denture). The forces applied were 150 N with an oblique component with a buccal inclination of 35° in the frontal region, and 600 N with a buccal inclination of 5° (molars) or solely vertical (premolar) in the distal region. The model with locator abutments showed higher stresses in all load cases in both analyzed implant variants and in the maxilla. The differences in stress distribution between the splinted and unsplinted variants were more significant in the distal region. According to the results of the present study, the amount of stress in bone tissue and dental implant parts was smaller in the splinted, bar-retained variant. The findings of this study can be useful in selecting the appropriate prosthetic design for implant-supported maxillary overdentures with partial palatal coverage.

Metaverse and Medical Diagnosis: A Blockchain-Based Digital Twinning Approach Based on MobileNetV2 Algorithm for Cervical Vertebral Maturation.

Advanced mathematical and deep learning (DL) algorithms have recently played a crucial role in diagnosing medical parameters and diseases. One of these areas that need to be more focused on is dentistry. This is why creating digital twins of dental issues in the metaverse is a practical and effective technique to benefit from the immersive characteristics of this technology and adapt the real world of dentistry to the virtual world. These technologies can create virtual facilities and environments for patients, physicians, and researchers to access a variety of medical services. Experiencing an immersive interaction between doctors and patients can be another considerable advantage of these technologies, which can dramatically improve the efficiency of the healthcare system. In addition, offering these amenities through a blockchain system enhances reliability, safety, openness, and the ability to trace data exchange. It also brings about cost savings through improved efficiencies. In this paper, a digital twin of cervical vertebral maturation (CVM), which is a critical factor in a wide range of dental surgery, within a blockchain-based metaverse platform is designed and implemented. A DL method has been used to create an automated diagnosis process for the upcoming CVM images in the proposed platform. This method includes MobileNetV2, a mobile architecture that improves the performance of mobile models in multiple tasks and benchmarks. The proposed technique of digital twinning is simple, fast, and suitable for physicians and medical specialists, as well as for adapting to the Internet of Medical Things (IoMT) due to its low latency and computing costs. One of the important contributions of the current study is to use of DL-based computer vision as a real-time measurement method so that the proposed digital twin does not require additional sensors. Furthermore, a comprehensive conceptual framework for creating digital twins of CVM based on MobileNetV2 within a blockchain ecosystem has been designed and implemented, showing the applicability and suitability of the introduced approach. The high performance of the proposed model on a collected small dataset demonstrates that low-cost deep learning can be used for diagnosis, anomaly detection, better design, and many more applications of the upcoming digital representations. In addition, this study shows how digital twins can be performed and developed for dental issues with the lowest hardware infrastructures, reducing the costs of diagnosis and treatment for patients.

Metaverse and Healthcare: Machine Learning-Enabled Digital Twins of Cancer.

Medical digital twins, which represent medical assets, play a crucial role in connecting the physical world to the metaverse, enabling patients to access virtual medical services and experience immersive interactions with the real world. One serious disease that can be diagnosed and treated using this technology is cancer. However, the digitalization of such diseases for use in the metaverse is a highly complex process. To address this, this study aims to use machine learning (ML) techniques to create real-time and reliable digital twins of cancer for diagnostic and therapeutic purposes. The study focuses on four classical ML techniques that are simple and fast for medical specialists without extensive Artificial Intelligence (AI) knowledge, and meet the requirements of the Internet of Medical Things (IoMT) in terms of latency and cost. The case study focuses on breast cancer (BC), the second most prevalent form of cancer worldwide. The study also presents a comprehensive conceptual framework to illustrate the process of creating digital twins of cancer, and demonstrates the feasibility and reliability of these digital twins in monitoring, diagnosing, and predicting medical parameters.

Phase Separation in Wetting Ridges of Sliding Drops on Soft and Swollen Surfaces.

Drops in contact with swollen, elastomeric substrates can induce a capillary mediated phase separation in wetting ridges. Using confocal microscopy, we visualize phase separation of oligomeric silicone oil from a cross-linked silicone network during steady-state sliding of water drops. We find an inverse relationship between the oil tip height and the drop sliding speed, which is rationalized by competing transport timescales of the oil molecules: separation rate versus drop-advection speed. Separation rates in highly swollen networks are as fast as diffusion in pure melts.

Novel Local Chimeric Flap Based on Tunnelized Facial Artery Myomucosal Island Flap and Submandibular Gland Flap for Reconstructions After Oral Squamous Cell Carcinoma Surgery.

The reconstruction of oral tongue and floor of mouth defects after resections of squamous cell carcinoma is a challenging task in reconstructive surgery aiming for appropriate restoration of oral function and quality of life improvement. In this study, the authors introduce the innovative reconstruction technique of medium-sized defects consisting of tunnelized facial artery myomucosal island flap and submandibular gland flap as the local chimeric flap pedicled on facial vessels. A retrospective case series evaluation of 4 patients suffering from oral cavity cancer (stages III and IVa), who underwent transoral tumor excision with neck dissection and immediate reconstruction in the time period September 2020 to July 2021, was conducted. No flap losses or flap-related complications were identified. No recurrences occurred during the follow-up at 11.0±4.5 months (range: 6-16 mo, median=11 mo). Tunnelized facial artery myomucosal island flap and submandibular gland flap local chimeric flap expands the reconstruction options of medium-sized defects after ablative oral cancer surgery in carefully selected patients primarily not suitable for free flap reconstructions.

Cloaking Transition of Droplets on Lubricated Brushes.

We study the equilibrium properties and the wetting behavior of a simple liquid on a polymer brush, with and without the presence of lubricant by multibody Dissipative Particle Dynamics simulations. The lubricant is modeled as a polymeric liquid consisting of short chains that are chemically identical with the brush polymers. We investigate the behavior of the brush in terms of the grafting density and the amount of lubricant present. Regarding the wetting behavior, we study a sessile droplet on top of the brush. The droplet consists of nonbonded particles that form a dense phase. Our model and choice of parameters result in the formation of a wetting ridge and in the cloaking of the droplet by the lubricant; i.e., the lubricant chains creep up onto the droplet and eventually cover its surface completely. Cloaking is a phenomenon that is observed experimentally and is of integral importance to the dynamics of sliding droplets. We quantify the cloaking in terms of its thickness, which increases with the amount of lubricant present. The analysis reveals a well-defined transition point where the cloaking sets in. We propose a thermodynamic theory to explain this behavior. In addition, we investigate the dependence of the contact angles on the size of the droplet and the possible effect of line tension. We quantify the variation of the contact angle with the curvature of the contact line on a lubricant free brush and find a negative value for the line tension. Finally we investigate the effect of cloaking/lubrication on the contact angles and the wetting ridge. We find that lubrication and cloaking reduce the contact angles by a couple of degrees. The effect on the wetting ridge is a reduction in the extension of the brush chains near the three phase contact line, an effect that was also observed in experiments of droplets on cross-linked gels.

Cryofouling avoidance in the Antarctic scallop Adamussium colbecki.

The presence of supercooled water in polar regions causes anchor ice to grow on submerged objects, generating costly problems for engineered materials and life-endangering risks for benthic communities. The factors driving underwater ice accretion are poorly understood, and passive prevention mechanisms remain unknown. Here we report that the Antarctic scallop Adamussium colbecki appears to remain ice-free in shallow Antarctic marine environments where underwater ice growth is prevalent. In contrast, scallops colonized by bush sponges in the same microhabitat grow ice and are removed from the population. Characterization of the Antarctic scallop shells revealed a hierarchical micro-ridge structure with sub-micron nano-ridges which promotes directed icing. This concentrates the formation of ice on the growth rings while leaving the regions in between free of ice, and appears to reduce ice-to-shell adhesion when compared to temperate species that do not possess highly ordered surface structures. The ability to control the formation of ice may enable passive underwater anti-icing protection, with the removal of ice possibly facilitated by ocean currents or scallop movements. We term this behavior cryofouling avoidance. We posit that the evolution of natural anti-icing structures is a key trait for the survival of Antarctic scallops in anchor ice zones.

Oral presentation of paraneoplastic pemphigus as the first sign of tonsillar HPV associated squamous cell carcinoma. A case report.

BACKGROUND: Paraneoplastic pemphigus (PNP) in the oral cavity is a rare variant of blistering pemphigus disease closely associated with mostly malignant tumors. The diagnosis may even precede an underlying malignancy enabling early detection. Here, we describe a previously unreported case of PNP associated with HPV-related tonsillar squamous cell carcinoma. METHODS AND RESULTS: A 50-year-old woman was referred to a dentist because of painful oral lesions resembling aphthae major and minor. Later, blisters appeared and an incisional biopsy was performed. Histological examination revealed an unusual coexistence of subepithelial and intraepithelial blisters raising suspicion of paraneoplastic pemphigus. The patient underwent 18F-FDG PET/MRI, showing a metabolically active process in the left palatal tonsil. Diagnostic biopsy revealed HPV type 16 associated tonsillar squamous cell carcinoma. A left tonsillectomy with elective left-sided neck dissection was performed. The postoperative period was complicated by bilateral fluidothorax. Two weeks after radical tumor removal, the mucosal and skin lesions of PNP disappeared. The patient currently shows no evidence of recurrence either of malignancy or PNP eight months after the surgery. CONCLUSION: PNP is a rare autoimmune blistering disease characterized by polymorphous cutaneous and mucosal lesions associated with internal neoplasms including HPV associated squamous cell carcinoma of a tonsil. In order to identify an occult malignancy, a whole-body PET/CT or PET/MRI scan is recommended. Rarely, accurate patient management may depend on the dentist being familiar with this entity and on interdisciplinary cooperation involving dermatologist, radiologist, pathologist, and pneumologist. A strict patient follow-up is indicated.

Cervical lymphocele: A rare complication following salvage surgery for ocular adnexal apocrine adenocarcinoma. A case report and review of the literature.

BACKGROUND: An ocular adnexal apocrine adenocarcinoma (OAAA) is an extremely rare, but potentially aggressive and life-threatening tumor with ill-defined management based only on recommendations from a limited number of reported cases. The development of cervical lymphocele following neck dissection is a very rare complication, but one with well established methods for prevention and treatment. Here we describe a previously unreported case of salvage surgery including neck dissection for OAAA in addition to an emergence of cervical lymphocele. A literature review of current knowledge on both pathological conditions is included. METHODS AND RESULTS: A 58-year-old man suffering from OAAA, previously treated with multiple eye-sparing excisions and adjuvant proton therapy, underwent salvage surgery for locoregional recurrence of the tumor. A partial orbitectomy with orbital exenteration, primary reconstruction and left-sided neck dissection was performed. The procedure was complicated by a cervical lymphocele resolved after the surgical therapy. The patient remained disease-free during the one-year follow-up. CONCLUSION: OAAA is a locally aggressive tumor with potential to local or distant metastatic spread. Whole-body staging, regular clinico-radiological follow-up and stage-dependent therapy with surgery as the first-choice treatment is required. A cervical lymphocele as a complication of especially left-sided neck dissection is managed with a conservative or surgical therapy according to the level of lymph leakage, extent and localization of lesions, presence of local or systemic disorders and the period from primary surgery.

Linear shrinkage of hydrogel coatings exposed to flow: interplay between dissolution of water and advective transport.

We investigate the shrinkage of a surface-grafted water-swollen hydrogel under shear flows of oils by laser scanning confocal microscopy. Interestingly, external shear flows of oil lead to linear dehydration and shrinkage of the hydrogel for all investigated flow conditions irrespective of the chemical nature of the hydrogel. The reason is that the finite solubility of water in oil removes water from the hydrogel continuously by diffusion. The flow advects the water-rich oil, as demonstrated by numerical solutions of the underlying convection-diffusion equation. In line with this hypothesis, shear does not cause gel shrinkage for water-saturated oils or non-solvents. The solubility of water in the oil will tune the dehydration dynamics.

Retromandibular Transparotid Approach for the Treatment of Benign Nontraumatic Conditions of the Mandible. A Retrospective Consecutive Case-Series Study.

ABSTRACT: The retromandibular transparotid approach enables the most direct access to the central and posterior part of the mandibular ramus including the condylar region. So far it has not been widely used for the management of benign pathology of the mandible. The purpose of this study was to evaluate the utilization rate of this approach in the nontrauma setting including the determination of suitable indications for this access. In total, 105 patients with 107 retromandibular transparotid approaches performed in the 6.5 years (from May 2014 to November 2020) were evaluated. Patients suffering from nontrauma pathology accounted for 4.7% of all cases. The recurrences of different types of odontogenic cysts and secondary chronic osteomyelitis were surgically managed via this approach with aesthetically acceptable resultant scar achievement and no identified postoperative complications. All lesions resolved and no recurrences occurred during the follow-up 32.0 ±â€Š20.7 months (range 6 to 59 months, median = 26 months). The retromandibular transparotid approach may be considered for the enucleation of benign bone lesions in selected patients. Another type of surgery for the management of benign nontraumatic conditions in an accessible area without requirements for continuity resection and jaw reconstruction may be also suitable for using this approach.

Frost spreading and pattern formation on microstructured surfaces.

Frost is found in nature as a symphony of nucleation and heat and mass transport, cascading from angstroms to several meters. Here, we use laser-induced fluorescence microscopy to investigate the pattern formation of frost growth in experiments which tune the mesoscopic length scale by using microstructured pillar arrays as a frost condenser surface. By controlling the degree of surface supercooling and the amount of condensate, different modes of frost patterning are uncovered, ranging from complete surface coverage to fractal-looking and limited-coverage structures of spiky appearance.

Super liquid repellent surfaces for anti-foaming and froth management.

Wet and dry foams are prevalent in many industries, ranging from the food processing and commercial cosmetic sectors to industries such as chemical and oil-refining. Uncontrolled foaming results in product losses, equipment downtime or damage and cleanup costs. To speed up defoaming or enable anti-foaming, liquid oil or hydrophobic particles are usually added. However, such additives may need to be later separated and removed for environmental reasons and product quality. Here, we show that passive defoaming or active anti-foaming is possible simply by the interaction of foam with chemically or morphologically modified surfaces, of which the superamphiphobic variant exhibits superior performance. They significantly improve retraction of highly stable wet foams and prevention of growing dry foams, as quantified for beer and aqueous soap solution as model systems. Microscopic imaging reveals that amphiphobic nano-protrusions directly destabilize contacting foam bubbles, which can favorably vent through air gaps warranted by a Cassie wetting state. This mode of interfacial destabilization offers untapped potential for developing efficient, low-power and sustainable foam and froth management.

How Frost Forms and Grows on Lubricated Micro- and Nanostructured Surfaces.

Frost is ubiquitously observed in nature whenever warmer and more humid air encounters colder than melting point surfaces (e.g., morning dew frosting). However, frost formation is problematic as it damages infrastructure, roads, crops, and the efficient operation of industrial equipment (i.e., heat exchangers, cooling fins). While lubricant-infused surfaces offer promising antifrosting properties, underlying mechanisms of frost formation and its consequential effect on frost-to-surface dynamics remain elusive. Here, we monitor the dynamics of condensation frosting on micro- and hierarchically structured surfaces (the latter combines micro- with nano- features) infused with lubricant, temporally and spatially resolved using laser scanning confocal microscopy. The growth dynamics of water droplets differs for micro- and hierarchically structured surfaces, by hindered drop coalescence on the hierarchical ones. However, the growth and propagation of frost dendrites follow the same scaling on both surface types. Frost propagation is accompanied by a reorganization of the lubricant thin film. We numerically quantify the experimentally observed flow profile using an asymptotic long-wave model. Our results reveal that lubricant reorganization is governed by two distinct driving mechanisms, namely: (1) frost propagation speed and (2) frost dendrite morphology. These in-depth insights into the coupling between lubricant flow and frost formation/propagation enable an improved control over frosting by adjusting the design and features of the surface.

How a water drop removes a particle from a hydrophobic surface.

To understand the removal of particles from surfaces by water drops, we used an inverted laser scanning confocal microscope to image the collision between a water drop and a particle on a flat polydimethylsiloxane (PDMS) surface. The dynamic drop-particle contact line was monitored by fixing the drop directly above the objective lens while moving the sample stage at well-defined speeds (10-500 µm s-1). The lateral force acting on the drop during the collision was measured as a function of speed, using a force sensor mounted on the microscope. Depending on the collision speed, the particle either stays attached at the rear of the drop or detaches from it. We propose a criterion to determine whether the particle remains attached to the drop based on the capillary and resistive forces acting on the particle during the collision. The forces measured when the particle crosses the air-water interface are compared to existing models. We adapted these to account for rolling of the particle. By comparing our experimental measurements with an analytical model for the capillary torque acting on a particle rolling at an interface, we provide detailed insights on the origins of the resistive force acting on the particle when it is pushed or pulled by the drop. A low friction force between the surface and the particle increases the likelihood of particle removal.

General and oral health status of preterm one-year-old very low and extremely low birthweight infants (a cross - sectional study).

AIMS: The aim of the present study was to evaluate the general and oral health status of a group of preterm one-year-old very low (VLBW) and extremely low birthweight (ELBW) infants and make a comparison with full-term one-year-old normal birthweight infants (NBW). METHODS: A cross-sectional study was conducted in 102 one-year-old preterm VLBW and ELBW infants, and the data obtained were compared to 87 one-year-old full-term NBW infants. The infants' medical histories were obtained from hospital records and interviews with the mothers. The oral cavities of all infants were examined under the same conditions. The chi-square test, Pearson's chi-square test of independence and Mann-Whitney test were used for the statistical evaluation, with P < 0.05 considered statistically significant. Relative risk (RR) and 95% confidence interval (CI) estimates for variables significantly associated with oral findings were calculated. RESULTS: Both perinatal variables (gestational age, mode of delivery, birthweight, Apgar score, resuscitation, orotracheal intubation and presence of intraoral pathology) and neonatal variables (antibiotic treatment and infections) had a significant association with prematurity, VLBW and ELBW. The one-year-old preterm VLBW and ELBW infants frequently suffered from general diseases, frequently received regular medication and had fewer erupted primary teeth; they also had a higher prevalence of developmental defects of the enamel and deformations of the hard palate. CONCLUSION: This study confirmed anamnestic, medical and oral differences between one-year-old preterm VLBW and ELBW and full-term NBW infants.