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Comparative study between Retroseptal Transconjunctival and Subciliary Approach for Fixation of the Infraorbital Rim Associated with Zygomaticomaxillary Complex Fracture: A Prospective study
No full textThe zygomaticomaxillary complex (ZMC) forms a major paired buttress of the midfacial skeleton. This buttress is important to maintain the structural, functional and aesthetic appearances of the facial skeleton. A fracture involving the zygomaticomaxillary complex most often occurs as a tripod, tetrapod or quadripod fashion and is also known as trimalar or malar fracture. Zygomaticomaxillary complex fracture requires three-point fixation at IOA, frontozygomatic region, and zygomaticomaxillary buttress to ensure maximum stability. Any disruption in the malar prominence due to fracture leads to aesthetic, psychological and functional significance. This disruption leads to impairment in ocular and mandibular function. Hence proper diagnosis and sufficient correction are mandatory for both cosmetics and function. There are so many transcutaneous and transconjunctival approach for the infra orbital rim fixation. But none of them considered as gold stranded. All the approach as its own merits and demerits. The aim of our study is to evaluate and compare between retroseptal transconjunctival and subciliary approach for fixation of the infraorbital rim associated with zygomaticomaxillary complex fracture
Effect of Bone Graft and Platelet Rich Fibrin With and Without Alendronate in the Management of Intrabony Periodontal Defect: A Randomized Clinical study
No full textBACKGROUND:
Periodontal disease is characterized by the presence of gingival inflammation, periodontal pocket formation, and loss of connective tissue attachment and alveolar bone around the affected teeth. The ultimate goal of periodontal therapy is to regenerate the lost periodontal tissues, including cementum, periodontal ligament and alveolar bone. The aim of periodontal therapy is to protect and maintain the patient’s natural dentition over his or her lifetime for optimal comfort, function and esthetic appearance. The regenerative therapy includes various treatment modalities such as use of bone grafts, GTR etc. Various bone grafts and bone replacement graft materials have been used, and growth factors have been incorporated in the bone grafts to stimulate the progenitor cells to form new tissues. Hence, the aim of the present study is to evaluate the effect of bone graft and platelet rich fibrin with and without alendronate in the management of intrabony periodontal defect.
MATERIALS AND METHOD:
The study sample included 20 patients, 9 male and 11 females, between 25 - 50 years with 20 intra bony defects with probing pocket depth of ≥ 5mm requiring periodontal flap surgery. Sites were randomly divided and treated with one of the following: Group-A open flap debridement followed by placement of platelet rich fibrin (PRF) and bone graft (Perioglas). Group-B open flap debridement followed by placement of platelet rich fibrin (PRF), alendronate and bone graft (Perioglas). Clinical parameters recorded were plaque index, gingival index, pocket depth, relative attachment level, radiographic defect fill were recorded at baseline and 6 months. Statistical analysis was done using SPSS software.
RESULTS:
The results of present study demonstrate that in all the sites there was a significant improvement in clinical and radiographic parameters, thereby improving periodontal status.
CONCLUSION:
• Perioglas, PRF and ALN were all shown to be safe to use, without causing any immunologic or antigenic reactions in any of the treated patients.
• Perioglas appears to be a suitable vehicle to administer biologic substances like PRF and growth factors to induce new bone regeneration.
• A combination therapy with Perioglas + PRF is also found to be effective.
• The present study found that adding a single titrated dose of host modulating agent like ALN marginally improved the predictability of bone formation
Comparative Evaluation of Flexural and Impact Strength of Denture Base Acrylic Resin Using Different Processing Methods: An In Vitro study
No full textSTATEMENT OF THE PROBLEM:
Chief Limitation of Polymethylmethacrylate denture base material was its inadequate mechanical property. Different processing methods of Polymethylmethacrylate have varying influences on the mechanical properties of denture base material.
PURPOSE OF THE STUDY:
The Aim of our In-vitro study was to comparatively evaluate the flexural and impact strength values between CAD-CAM, Compression-molded and Injection molded Polymethylmethacrylate specimens.
MATERIALS AND METHODS:
A total of 66 acrylic rectangular specimens of ISO Standardization (64 x10 x3.3 mm) were fabricated. Study was conducted between three groups: Group I (n=22)-CAD-CAM Milled specimens (Ruthinium, India), Group II (n=22)- Compression-molded specimens (Dental Products of India, Chennai), Group III (n=22)- Injection-molded specimens (SR- Ivocap High Impact, Ivoclar Vivadent). Flexural strength was evaluated using four-point bend test and Impact strength by IZOD Impact tester. Kruskal Wallis unpaired test was used to compare the mean
values between groups and Mann Whitney U test was used to carry out pair wise comparison.
RESULTS:
Flexural strength of CAD-CAM samples were found to be statistically highest followed by injection molded specimens. Conversely, Impact strength of injection molded specimens were highest followed by CAD-CAM specimens. Both values were found to be least among compression-molded specimens.
CONCLUSION:
CAD-CAM specimens exhibited higher flexural strength whereas Injection molded specimens had the highest impact strength
Evaluation of Flexural Strength of Heat Cure Denture Base Material Reinforced with 1wt% of Different Nanoparticles and Sizes: An Invitro study
No full textPURPOSE:
To evaluate the effect of adding 1wt% of Al2O3, SiO2, and ZrO2 nanoparticles to heat cure acrylic resins on their flexural strength.
INTRODUCTION:
PMMA has been the material of choice for denture base materials because of its ease of use, low cost, esthetics, polishability, light weight. But the material has the disadvantage of low mechanical properties such as low flexural strength and impact strength resulting in fracture of the denture when subjected to occlusal forces.
Reinforcement with fibres, metal oxides, wires have been tried to improve the mechanical properties. Recent advancements in the field of nanotechonology has enabled the application of nanoparticles for the mechanical reinforcement of PMMA to improve its mechanical properties.
Nanoparticles are considered effective reinforcing materials. Nano particles are used as fillers in polymeric materials to improve the mechanical properties. The Nanoparticles are characterized by the small size, large specific surface area, and strong interfacial interaction with organic polymers. The dimension of the material is in nanometer dimension, which leads to unique properties. The purpose of the study is to evaluate the flexural strength of heat cure PMMA on adding 1wt% of Al2O3, SiO2, & ZrO2 of diameter 5nm and 15nm.
MATERIALS AND METHODS:
A total of 88 specimens are prepared in 4 groups (Control, 1wt% Al2O3, 1wt% SiO2, 1wt% ZrO2) and 3 subgroups (5 nm & 15 nm of all Nano groups) (n =22/group). The PMMA powder and nanoparticles are mixed with each other by means of ball milling at 350 rpm for one hour. The templates of dimension 65mm length, 10mm width, 3 mm thickness is invested in type III dental stone.
The powder liquid ratio is followed according to the manufacturers ratio as 20ml for 43.8g. The material is mixed and placed in the mould which is then placed under hydraulic press. The flask is then kept in water bath for curing. It is placed for two hours and then boiled for one hour.
Then the specimens are deflasked trimmed and policed. The specimens are polished with 200-, 400-, and 600-grit abrasive paper to provide a standard surface before testing and then suspended in distilled water. Flexural strength is measured via three-point bending tests. Subsequently, SEM analysis is performed for specimens from each group to ensure homogenous distribution.
RESULTS:
The flexural strength of polymethylmethacrylate (PMMA) after adding 1wt% of aluminum trioxide 15nm significantly increased (p ˂ 0.05) followed by 1wt% of silicon dioxide 15nm. The electron microscopy analysis revealed that the particles were homogeneously dispersed in PMMA matrix.
CONCLUSION:
The mechanical properties of heat cure PMMA can be increased by addition of nanoparticles to PMMA powder. 1wt% of aluminium trioxide-15nm diameter has significantly improved the flexural strength of PMMA
Prevalence of Colour Vision Deficiency and Ability to Differntiate Colour among Dentists: In Vivo study
No full textBACKGROUND:
Colour vision deficiency is a common disorder of vision that results in the inability to see certain colours or perceive their differences. It has been reported that most people with colour vision defects remain undiagnosed. Colour vision deficiency is under reported due to a lack of its awareness and the absence of proper screening to detect this in the general population. Numerous inadequacies and inconsistencies exist or could occur in procedures which includes colour discord between porcelain layers, batch colour variations, clinical colour deficiency, lack of colour educating and training, inappropriate shade matching conditions and methods, poor colour communication and inaccurate colour reproduction. There is a strong causal connection among these mentioned factors, which sometimes result in mismatching of the restoration shades. With advancement in smartphone technology and proliferation of medical software applications, physicians are increasingly incorporating smartphones into their daily practice.
AIM OF THE STUDY:
The aim of the study is to find the prevalence of colour vision deficiency among dentists and ability of dentists to differentiate colours and also to find the similarity between the Ishihara colour plates and our own developed Eyedent application.
MATERIALS AND METHODS:
Ishihara plates has been used to find the ability of dentists to differentiate colours and newly developed mobile application has been used to find the ability to differentiate colour and also to find similarity of results between Ishihara and Eyedent application.
RESULTS:
8 dentists were suffered from colour vision deficiency over the others. Those who are suffered from colour deficiency can use digital methods for colour matching or asking the assistant to match the colour of the intra oral and maxilla facial prosthesis as an alternative method. Responses from 4 plates of Ishihara and Eyedent application shows no statistical difference which means the responses obtained from 4 plates on Ishihara and Eyedent was similar.
CONCLUSION:
This study suggests that some dentists who were completely unaware about their colour vision deficiency and there may be high chance of doing inappropriate shade matching results in esthetic failure of the prosthesis. Those who are suffered from colour deficiency can use digital methods for colour matching or asking the assistant to match the colour of the intra oral and maxilla facial prosthesis as an alternative method
Evaluation and Comparison of the Transverse Strength and Residual Monomer Content of Two Different Heat Cure Denture Base Resins Processed by Different Polymerization Techniques: An In Vitro study
No full textBACKGROUND:
Inspite of advancements in material properties of heat cure acrylic resin, fracture of denture base and allergic reactions due to release of residual monomer is encountered frequently. To improve strength and to reduce residual monomer, different polymerization methods need to be investigated.
AIM AND OBJECTIVES:
Aim of this study was to evaluate and compare transverse strength and residual monomer content of two different heat cured denture base resins polymerized by conventional water bath and by autoclave.
METHODOLOGY:
Samples were prepared with Acralyn-H conventional heat cure resin and Acralyn-H super hi-impact resin using metal dies. Samples were polymerized in water bath at 74°C for 2 hours followed by 100°C for 1 hour and in autoclave at 121°C and 210 kPa for 30 minutes at holding temperature. Transverse strength specimens were immersed in distilled water, placed in an incubator at 37°C for 48 hours and then tested for transverse strength in Universal testing machine. Specimens for residual monomer content estimation were weighed and each specimen was extracted in methanol using Soxhlet extractor and then read at 230nm in UV spectrophotometer. Concentrations of residual monomer were evaluated and weight fractions were calculated.
RESULTS:
The results of this study showed a statistically significant difference in transverse strength of Acralyn-H conventional heat cure resin polymerized by autoclave, whereas all other groups showed a non-significant result.
CONCLUSION:
Autoclave can be used as an alternative polymerization technique as it has shown similar results when compared with water bath and time required for polymerization is also reduced
