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In recent years, the interest in human-robot interactions has added a new dimension to the on-line path planning problem by requiring a method that guarantees a risk-free path. This paper presents a streamlined search algorithm for fast path modification. The algorithm is formulated as an optimization problem that evaluates alternative paths nearby each obstacle. Each path is evaluated based on the value of the danger assigned to that path. To reduce the size of the search space, the minimum number of via points necessary to alter the path is initially obtained using a geometrical method. Given the number of via points, the algorithm proceeds to locate the via points around the obstacle such that the resulting path through these via points satisfies all problem constraints. Obtaining a solution in this way renders a fast algorithm for path modification, while it better avoids problems often encountered in other gradient-based search algorithms. Case studies for two planar robots are provided to highlight some of the advantages of the proposed algorithm. Experimental results using a CRS-F3 robot manipulator validate the effectiveness of the algorithm for applications involving human-robot interactions.

Background: In soft tissue regeneration, the clinical efficacy of fibrin membranes has been a pressing concern. The key to this efficacy lies in the stability of membrane and its controlled absorption. Human serum albumin, with its influence on the formation and stability of fibrin networks, could hold the key to developing a more stable alternative. This study investigates the ultrastructure and biodegradability of plasma albumin-activated gel, a potential game-changer in the field., Methods: Blood samples were collected from the participants and centrifuged to obtain the concentrated growth factor. The poor platelet plasma syringe was placed inside the activated plasma albumin gel device. The ultrastructure of the membrane was examined using a scanning electron microscope (SEM). The weight difference was measured over 21 days to investigate the biodegradability of the samples., Results: Twenty-two samples were prepared from six individuals (three males and three females). Based on SEM images, activated albumin gel after 21 days in Hank's solution exhibited a significant decrease in density and evident signs of surface degradation. The weight was significantly reduced after 21 days (p < 0.05)., Conclusion: In the present study, the investigation of the ultrastructure and biodegradability of activated albumin gel showed that, based on the observed weight difference, the amount of biodegradation is high, and it may be necessary to use a thicker membrane compared to the conventional thickness of the connective tissue graft., Key Points: Enhanced stability and biocompatibility: The study highlights plasma albumin-activated gel's potential as a soft tissue scaffold, demonstrating significant biodegradation and structural changes that support cell infiltration and nutrient exchange, essential for tissue regeneration. Controlled degradation profile: Plasma albumin gel offers a prolonged biodegradation period compared to conventional fibrin membranes, making it suitable for applications requiring stable, long-lasting scaffolds in soft tissue regeneration. Future clinical applications: Findings suggest that thicker plasma albumin membranes may be needed for optimal effectiveness, paving the way for further exploration in clinical trials and animal models to validate this approach in soft tissue grafting., Plain Language Summary: This study investigates plasma albumin-activated gel as a promising material for supporting soft tissue repair, particularly in periodontal regeneration. Traditional materials, such as fibrin membranes, are often used to aid healing, but their rapid breakdown can limit effectiveness in the body. Plasma albumin, a protein naturally found in human blood, might offer a more stable alternative by forming a longer-lasting structure. In this study, researchers processed blood samples from participants to create the gel, examining its structure under a powerful microscope and tracking changes in weight over 21 days to assess its breakdown. Results showed that the gel gradually became less dense and more porous, allowing for cell movement and nutrient flow-both critical for tissue repair. Additionally, a significant reduction in weight indicated a controlled breakdown over time. These findings suggest that plasma albumin-activated gel may serve as a more durable scaffold for soft tissue regeneration, potentially improving healing outcomes in periodontal applications where a stable, longer-lasting material is needed., (© 2024 The Author(s). Clinical Advances in Periodontics published by Wiley Periodicals LLC on behalf of American Academy of Periodontology.)

The prevalence of the elderly population increased in the 20th century, as described in the World Health Organization 2004 Annual Report. The use of tilted implants parallel to the anterior wall of the maxillary sinus or the mental foramen/inferior alveolar nerve has been proposed for the treatment of the atrophic edentulous ridge. The aim of this study was to evaluate stress and strain magnitude in tapered and cylindrical surrounding bones. A 3D finite element model of an edentulous mandible was constructed. Two models of implants were used: cylindrical and tapered BEGO Semados RI Implants. Four implants were inserted between the bilateral mental foramen according to All-on-Four concept, and a mandibular bar was designed to use with the All-on-Four bar supported models. A vertical and 30 degree vertical load of 100 N was applied to both cylindrical and tapered implants models. Strain and stress were analyzed with ANSYS software (ANSYS R18.0). The maximum stress and strain were applied in all axes for the posterior man-dibular areas in the crestal region of the bone, and for the anterior areas at the intraosseous contact site. Also, the stress and strain of the bone under force in all axes in all areas for tapered implants is less compared to that for cylindrical implants. We found that the highest rate of bone resorption occurs in the posterior areas near the junction of the fixture with the abutment of implant, and in the anterior areas near the end of the fixture of implant. Still, more research on the subject is needed.

Objective: Contemporary implantology is moving toward less invasive approaches. To date, several techniques have been proposed for maxillary sinus lift surgery. In this article, we introduce a new technique for maxillary sinus floor elevation that is less invasive than the osteotome technique., Methods and Materials: In the vertical expander screw (VES) technique, which uses a combination of drilling and bone-expander screws; a primary implant hole is created. Bone expander screws are used in lateral and vertical dimensions to elevate the sinus membrane., Results: The results at the two-year follow-up revealed bone formation around the implant body in the bony sinus cavity for three patients. Accordingly, 100% survival and success rates were reported for implants placed with VES technique., Conclusion: The maxillary sinus floor can be elevated to the desired height with a VES technique with minimal invasion. The VES technique can be used as an alternative to elevate the sinus floor with less invasion than the osteotome technique.

The frenum is a mucosal fold that attaches the lips or cheeks to the alveolar mucosa, gingiva, and underlying periosteum. Consequences of an abnormal frenal attachment include gingival recession, decreased vestibular depth, decreased range of lip movement, and involvement of interdental papilla, causing a diastema. Several methods to eliminate ectopic frenal attachments have been suggested, including frenectomy (elimination) and frenotomy (repositioning). This case report describes the use of a modified frenectomy technique in a 15-year-old girl with excess gingiva between the maxillary central incisors, which exhibited a 3-mm diastema. First, a semilunar primary incision was made in the palatal surface at a 5-mm distance from the tip of the papilla. Next, sulcular incisions were made around the tooth, and the papilla was transposed to the buccal via a papilla preservation flap. After complete elimination of frenal attachments in the bone, the flap was repositioned and sutured to the palatal surface. Afterward, the frenum was classically cut and sutured. Through this approach, the position of the frenum was changed apically without invading the papilla. At the 3-month follow-up, it was found that the modified technique (combination of papilla preservation flap and frenotomy) had minimized the surgical scar on the buccal surface, preserved the papilla, and yielded optimal esthetic results.

Survival of dental implants depends on several factors; soft tissue (ST) management around dental implants is one of the foremost. Several studies have suggested techniques for ST management around dental implants, but none of them has discussed a suitable timetable for this process. This study aimed to review published articles related to the timing of ST management around dental implants and suggest a customized treatment protocol. A search of the PubMed database was conducted; the search was limited to English-language articles published from January 1995 to July 2015 with available full texts. Only in vivo studies and clinical trials in relation to the terms soft tissue management, management timing, keratinized mucosa, free gingival graft, connective tissue graft, soft tissue, augmentation, and dental implant were included. A total of 492 articles were reviewed, and eventually 42 articles were thoroughly evaluated. Those with treatment protocols in terms of the timing of ST grafting were selected and classified. ST management around dental implants may be done prior to the surgical phase, after the surgical phase, before loading, or even after loading. A thick gingival biotype is more suitable for implant placement, providing more favorable esthetic results. A treatment plan should be based on individual patient needs as well as the knowledge and experience of the clinician. The width and thickness of keratinized tissues, the need for bone management, and local risk factors that influence esthetic results determine the appropriate time for ST augmentation procedures.