Shilpa Shetty

The aim of this in vitro study was to compare the change in the retentive force and removal torque of three attachment systems during simulation of insertion-removal cycles. Edentulous mandibular models were made with heat-cured polymethyl methacrylate resin. Two implant replicas (CMI), of 3.75 mm diameter and 10 mm length, were placed in the intraforaminal region. Acrylic resin mandibular overdentures were fabricated and provision was made to receive three different overdenture attachment systems, prefabricated ball/o-ring attachment (Lifecare Biosystems, Thane, India), Hader bar and clip attachment (Sterngold, Attleboro, MA), and Locator(®) implant overdenture attachment stud type (Zest Anchors LLC, USA). Using a universal testing machine, each of the models were subjected to 100 pulls each to dislodge the overdenture from the acrylic model, and the force values as indicated on the digital indicator were tabulated both before and after thermocycling (AT). Statistical analysis comp...

The study was undertaken to evaluate the parallelism between hamular-incisive-papilla plane (HIP) and the Campers plane. And to determine which part of the posterior reference of the tragus i.e., the superior, middle or the inferior of the Camper's plane is parallel to HIP using digital lateral cephalograms. Fifty edentulous subjects with well formed ridges were selected for the study. The master casts were obtained using the standard selective pressure impression procedure. On the deepest point of the hamular notches and the centre of the incisive papilla stainless steel spherical bearings were glued to the cast at the marked points. The study templates were fabricated with autopolymerizing acrylic resin. The subjects were prepared for the lateral cephalograms. Stainless steel spherical bearings were adhered to the superior, middle, inferior points of the tragus of the ear and inferior border of the ala of the nose using surgical adhesive tape. The subjects with study templates were subjected to lateral cephalograms. Cephalometric tracings were done using Autocad 2010 software. Lines were drawn connecting the incisive papilla and hamular notch and the stainless steel spherical bearings placed on the superior, middle and inferior points on the tragus and the ala of the nose i.e., the Campers line S, Campers line M, Campers line I. The angles between the three Camper's line and the HIP were measured and recorded. Higher mean angulation was recorded in Campers line S -HIP (8.03) followed by Campers line M-HIP (4.60). Campers line I-HIP recorded the least angulation (3.80). The HIP is parallel to the Camper's plane. The Camper's plane formed with the posterior reference point as inferior point of the tragus is relatively parallel to the HIP.

The purpose of this study was to evaluate the reliability of programming the articulator using the radiographs and the interocclusal records made during Jaw relation (Arrow point tracing) and Try-in stage. The study comprised of 15 edentulous subjects with well formed maxillary and mandibular ridges, with no signs and symptoms of temporomandibular joint disorders and neuromuscular disorders. Digital Orthopantomograph was taken for all the subjects. The condylar guidance angles were traced on Orthopantomograph for right and left sides and the values were recorded. The protrusive interocclusal records were made at jaw relation stage and at try-in stage using bite registration paste (Bitrex- vinyl polysiloxane) for all subjects. These interocclusal records were used to programme the Semi-adjustable articulator (Hanau Wide Vue) and the condylar guidance values on the right and left sides were recorded. The condylar guidance values so obtained were compared with the values obtained by Or...

Different proportions are described in the literature for smile designing, such as Golden proportion, Golden percentage, Preston's proportion, and recently, Recurring Esthetic Dental (RED) proportion. To evaluate the existence of RED proportion in natural dentition. To determine the relative height of maxillary lateral incisor and canine occurring in natural dentition so that it can be used in any of the above proportions. Fifteen male subjects and 15 female subjects in each of the different age groups of 18-23 years, 24-29 years and 30-35 years were selected for this study (total 90). Photographs of the subjects were taken using Nikon D200 camera with 135 mm lens and analyzed using Adobe Photoshop CS4 extended software. The height and width of maxillary central incisors, lateral incisors and canines were found out using the measuring tool provided in the software. Average width ratio and height ratio of maxillary lateral incisor to central incisor and maxillary canine to lateral incisor were calculated to check the existence of RED proportion in natural dentition. Average lateral incisor to central incisor height ratio for "small"- and "medium"-sized teeth was found to be 88% and for "tall"-sized teeth was found to be 84%. Average canine to lateral incisor height ratio for "small"- and "medium"-sized teeth was…

Aim: The main purpose of this study is to determine the dimensional accuracy of digital models as compared to that of study models and the reliability of electronic surveying. The study aims to measure and compare distances between selected landmarks on study models and ...

Bruxism is a movement disorder characterized by grinding and clenching of teeth. Awake bruxism is found more in females as compared to males while sleep bruxism shows no such gender prevalence. Etiology of bruxism can be divided into three groups psychosocial factors, peripheral factors and pathophysiological factors. Treatment modalities involve occlusal correction, behavioural changes and pharmacological approach. A literature search was performed using National Library of Medicine’s (NLM) Medical Subject Headings (MeSH) Database, Pubmed and Google search engines. The search term ‘Bruxism’ yielded 2,358 papers out of which 230 were review papers. Most of the papers selected were recently published during the period of 1996–2010 and very few of them were published before 1996.

Marked bactericidal activity of the electrolyzed acid water (EAW) and its less undesirable effects on biological tissues and the environment has been successfully utilized in dental practice. A review of literature reveals that not many studies have been performed to determine the disinfection effect of EAW on heat cured acrylic denture bases. The objective of the study is to determine the efficacy of EAW in disinfecting heat cured acrylic resin specimens as compared to the efficacy of disinfecting the specimens using 2% glutaraldehyde. Heat cured acrylic resin plates were immersed in Bacteria suspensions of Staphylococcus aureus and later disinfected using EAW which was produced using a custom made electrolyzing apparatus and 2% glutaraldehyde for different time intervals. The numbers of surviving bacteria were counted. As the control, the bacteria attached on the specimens were counted with out any disinfection treatment. The results obtained were statistically analyzed using ANOVA and post-hoc test. The disinfection potential of 2% glutaraldehyde was better than EAW when the specimens were disinfected for 1 and 3 min. Where as when the disinfection time was increased to 5 min there was no difference between EAW and 2% glutaraldehyde. However considering that the disinfecting time can be easily extended to 5 min, EAW can be effectively used for disinfecting the acrylic denture.

Impressions are important sources of cross contamination between patients and dental laboratories. As a part of infection control impressions contaminated with variety of micro-organisms via blood and oral secretions should be cleaned and disinfected or sterilized before being handled in dental laboratory. The purpose of this study was to determine the effect of autoclaving on dimensional stability of elastomeric impression material (polyvinyl siloxane—Affinis). In this in vitro study standardized stainless steel die as per ADA specification number 19 was fabricated. Polyvinyl siloxane (Affinis) light body and putty viscosity elastomeric impression materials were used. A total of 40 impressions of the stainless steel die were made and numeric coding system was used to identify the samples. Measurements were made using a measuring microscope. Distance between the cross lines CD and C′D′ reproduced in the impression were measured before autoclaving, immediately after autoclaving and 24 hours after autoclaving and dimensional change was calculated. The data obtained was subjected to statistical analysis. The mean difference in dimensional change between the three groups was not statistically significant (P > 0.05). However the results revealed that there was higher mean dimensional change immediately after autoclaving when compared to the other 2 time intervals. It is desirable to delay the casting of an autoclavable elastomeric impression material by about 24 hours. Though disinfection of impression is routinely followed autoclaving of impression is an effective method of sterilization.