Prosthetic Rehabilitation Options in Post-Ablative Maxillomandibular Microvascular Reconstructions.

Objective: Surgery remains the mainstay for managing most neoplasms arising in the head and neck area. Removable or fixed prostheses are commonly used for prosthetic rehabilitation of head and neck defects following surgical resection. Some major challenges in prosthetic rehabilitation after maxillomandibular microvascular reconstruction include excessive prosthetic space, soft tissue bulk, and occlusal disharmony in the remaining dentition. This review focuses on the challenges we have experienced in the real clinical scenario while rehabilitating reconstructed maxillomandibular defects and the effective prosthetic treatment options that could be considered in each situation. Discussion: Digital revolution has changed all arenas of life, and it has created a significant impact on cancer treatment planning and the delivery of quality treatment to the needy. Creating adequate retention while ensuring stability and support for the prosthesis can be challenging with temporary acrylic and cast partial removable dentures. Endosseous dental implants are considered a stable, reliable, and esthetic option for reconstruction with advantages such as increased chewing efficiency, preservation of the remaining bone height and width, and improved quality of life. The FP3 to RP5 (Misch's classification) are some commonly followed prosthetic rehabilitation options after microvascular reconstruction. The prosthetic design should permit the usage of interdental aids that ensure the longevity of prostheses. Conclusion: Occlusion-driven/prosthetic-driven implant-assisted prostheses are considered a reliable option that ensures stable and functional oral rehabilitation among patients with free fibula flap reconstruction. Multidisciplinary teamwork is mandatory for an optimal outcome that improves patients' quality of life.

NANOTEX BONE Graft along with Fibula Flap in the Reconstruction of Segmental Mandibular Defect: Protocol for Pilot Clinical Trial.

Introduction and objectives: Mandible reconstruction with vascularized fibula flap is the standard treatment for segmental mandibulectomy in patients with tumor or trauma. But the height of the fibula graft is insufficient for dental implant placement and prosthetic rehabilitation to replace the missing teeth, which in turn will compromise the functional efficiency and aesthetics of the patient. Although the bone height can be augmented through onlay grafting with iliac crest, it is associated with limitations like donor site morbidity and fast resorbability. This suggests the need for a synthetic biomaterial for vertical bone augmentation in implant dentistry.We have developed a biomimetic, porous, mechanically stable, and biodegradable nanocomposite named "NANOTEX BONE Graft" and its bone regeneration potential was evaluated in pre-clinical animal models. In this clinical trial, the safety as well as the efficacy of NANOTEX to augment new bone over fibula and further its ability to integrate with dental implants will be studied. The study has received the approval of the Ethics Committee of Amrita Institute of Medical Sciences and Central Drugs Standard Control Organization (CDSCO), India. Methods: We have designed a prospective, single-center, non-randomized pilot clinical study. Patients with benign tumor or trauma indicated for mandibular reconstruction followed by implant rehabilitation will be included in the study. Eligible patients will be enrolled after obtaining informed consent. The study will be initiated and followed up as per defined timelines. Highlights: Resection of benign mandibular tumours necessitates surgical removal of jaw bone and adjacent affected areas.The segmental mandibulectomy leaves the patient with functional impairments and aesthetic defects which in turn affect the quality of life.The standard treatment of reconstruction with vascularized fibula flap has challenge in achieving sufficient vertical bone height for implant placement and prosthetic rehabilitation.Alternate surgical techniques cause donor site morbidity and surgical complications.There is need for a synthetic biomaterial to be grafted over fibula for vertical bone augmentation.NANOTEX BONE Graft, a nanofibrous composite scaffold that mimics native bone, promote cell infiltration, neo-angiogenesis and new bone formation.Preclinical studies of NANOTEX in animal models showed bone tissue regeneration, better biodegradation in critical sized defects and efficient integration with dental implants.This clinical study propose to evaluate the safety and efficacy of NANOTEX bone graft augmented over fibula in bone regeneration and Titanium dental implant integration.

Relevance of Recurring Esthetic Dental (RED) proportion and golden proportion among patients attending a tertiary care center at Kochi, Kerala.

Background: Smile plays an essential part in facial esthetics. There have been some mathematical and geometric theories regarding smile designing in literature. The purpose of the study was to assess RED proportion and golden proportion among patients attending a tertiary care centre at Kochi, Kerala. Methods: Standardised frontal images of 106 subjects, 50 male and 56 females, were captured in the age bracket of 18-25 years. Pictures of the patients were obtained using a DSLR camera (CANON EOS-60D) and then digitally analysed. Measurements of each maxillary anterior tooth was recorded and then the theories of RED and golden proportion were employed and the figures recorded were statistically analysed. Results: The RED proportion was observed to be inconsistent, while progressing distally, Golden proportion was observed to be in 6-29% of the existing subject population. Conclusion: Within the limited sample size of the study, RED (Recurring Esthetic Dental) proportion and golden proportion failed to exist in Keralites.

Superhydrophilic multifunctional nanotextured titanium dental implants: in vivo short and long-term response in a porcine model.

Current clinical demand in dental implantology is for a multifunctional device with optimum mechanical properties, improved biocompatibility and bioactivity, and having differential interactions with cells and pathogenic agents. This would minimise bacterial infection, biofilm formation and modulate inflammation, leading to a fast and durable osseointegration. The present study intends to establish the multifunctional behaviour of surface modified titanium dental implants that are superhydrophilic, with unique micro-nano or nanoscale topographies, developed by a facile hydrothermal technique. Here, the short and long-term performances of these textured implants are tested in a split mouth design using a porcine model, in pre- and post-loaded states. Quantitative and qualitative analyses of the bone implant interphase are performed through µ-CT and histology. Parameters that evaluate bone mineral density, bone contact volume and bone implant contact reveal enhanced bone apposition with better long-term response for the nano and micro-nano textured surfaces, compared to the commercial microtextured implant. Concurrently, the nanoscale surface features on implants reduced bacterial attachment by nearly 90% in vivo, outperforming the commercial variant. This preclinical evaluation data thus reveal the superiority of nano/micro-nano textured designs for clinical application and substantiate their improved osseointegration and reduced bacterial adhesion, thus proposing a novel dental implant with multifunctional characteristics.

Effect of Particle Size of Nano-Oxides on Color Stability and Mechanical Properties of Maxillofacial Silicone Elastomers: An In Vitro Study.

PURPOSE: To evaluate the physical and mechanical properties of maxillofacial silicone elastomers following the incorporation of a specific particle size and concentration of nano-titanium dioxide (TiO2) and nano-zinc oxide (ZnO). MATERIALS AND METHODS: Nano-TiO2 and nano-ZnO of 20-nm and 40-nm particle sizes and in 1% and 2% concentrations were chosen. Silicone elastomer samples were prepared according to the manufacturer's recommendations. The nano-oxides were incorporated via hand spatulation. The samples were subsequently tested for hardness and color stability and were then subjected to aging in an aging chamber for 1,008 hours, following which they were again evaluated for hardness, color stability, and surface roughness. RESULTS: A significant change was noted in the physical and mechanical properties post-aging in all the groups. The samples with nano-TiO2 of 40-nm particle size/2% concentration had the highest hardness, while color stability and surface roughness were higher in samples with nano-TiO2 of 20-nm particle size/1% and 2% concentrations, respectively. CONCLUSION: It can be concluded that 20-nm nano-TiO2 particles best maintain the ideal properties of maxillofacial silicone elastomers and can potentially be used as alternative opacifiers when mixed with A-2186 maxillofacial silicone elastomers.

Biomimetic Properties of Engineered Periodontal Ligament/Cementum in Dental Implants.

The conventional concept of osseointegrated dental implants based on direct connection to alveolar bone lacks a structured periodontal ligament (PDL) as in natural tooth. This limits the physiologic and functional efficiency of the implant in cushioning occlusal overload, orthodontic tooth movement, and proprioception. Development of bio-mimetic implants that can satisfy the bio-functional requirements of the natural tooth will be an innovative approach and preliminary researches in this area has been reported. This review includes in vivo studies which reported structural features and functional efficiency of an artificial PDL or cementum developed around dental implants. The electronic search identified 12 animal studies and one human trial which utilized retained or adjacent natural tooth roots, exogenous scaffold materials, dental progenitor cells derived from PDL of extracted tooth root as PDL substitutes. The result of the review is dominated by bio-hybrid implants that used dental follicles separated on the particular embryonic day and cell sheets from immortalized human cells. A summary of the currently available research on artificial PDL/cementum around dental implants highlights the potential need of autologous cell-derived tissues to bioengineer a fully functional implant design.

Effect of chemical disinfectants and accelerated aging on maxillofacial silicone elastomers: An In vitro Study.

CONTEXT: Maxillofacial prostheses need frequent refabrication due to degradation of color and deterioration of physical properties of the elastomer. AIMS: This study attempted to evaluate the change in color stability, Shore A hardness, and surface roughness of two maxillofacial silicones, A-2186 and Cosmesil M511, when submitted to chemical disinfection and accelerated aging. SETTINGS AND DESIGN: This was a comparative in vitro study. SUBJECTS AND METHODS: The materials included two silicone elastomers - A-2186 and Cosmesil M511 (Factor II Incorporated) - functional intrinsic red pigment and three disinfectants - Fittydent tablet, chlorhexidine gluconate 4%, and neutral soap. The specimens in each group of elastomer were evaluated initially for color, hardness, and surface roughness, which were further divided into subgroups and subjected to disinfection and accelerated aging. The evaluation of color was performed with the help of an ultraviolet reflectance spectrophotometer. Shore A hardness was evaluated using a durometer and surface roughness, with a digital roughness tester followed by scanning electron microscopy analysis. STATISTICAL ANALYSIS USED:: Analysis of variance and Tukey's multiple comparison test were used for statistical analysis. RESULTS: Accelerated aging caused a significant decrease in color, increase in Shore A hardness, and variation in surface roughness in both silicone elastomer groups. Chemical disinfection presented significant changes in color and surface roughness whereas no significant effect on Shore hardness, irrespective of the disinfectant used. CONCLUSIONS: The maxillofacial silicone elastomers presented deterioration in color, hardening, and significant variations in surface roughness when subjected to chemical disinfection and accelerated aging, which provides a valid baseline for future research.

Prosthetic rehabilitation of surgically treated orbital defects - evisceration, enucleation, and exenteration: A case series.

The rehabilitation of a patient who has suffered the psychological trauma due to loss of an eye requires a prosthesis that will provide the optimum cosmetic and functional result. The mode of rehabilitation varies based on the type of defect and surgical approach being adopted. A case series of prosthetic rehabilitation of three types of orbital defects - evisceration, enucleation and exenteration have been reported in this article. The clinical relevance of surgical approaches highlights the preservation of remaining anatomic structures creating a negative space or concavity to aid in future prosthetic rehabilitation. A multidisciplinary management and team approach is essential in providing esthetics and to regain the confidence. Follow-up care for the patient is mandatory.