Scanning electron microscopic evaluation of root canal surfaces prepared with three rotary endodontic systems: Lightspeed, ProTaper and EndoWave

Background and Objectives: The purpose of this in vitro study was to  evaluate and compare the cleaning efficiency, preparation time, instrument deformation and fracture with LightSpeed (LS), ProTaper (PT) and  EndoWave (Ew) rotary instruments.Materials and Methods: A total of 45 freshly extracted human mandibular premolars were subjected for the study. They were divided into three groups, each group consisting of 15 teeth. Group 1: The canals were prepared with LS system; Group 2: PT rotary system, Group 3: Ew rotary system. All the groups were prepared according to manufacturerfs recommendation, using 5.25% sodium hypochlorite and 17%  ethylenediaminetetraacetic acid (dent wash, prime dent) alternately as an irrigants. Crowns of each tooth were removed with diamond disks at the level of cemento enamel junction. Canal length was determined by placing a size 10 K.file. The working length was 0.5 mm short of canal length. Two longitudinal grooves were prepared on the lingual and buccal surfaces of each root to facilitate vertical splitting with a chisel after canal  instrumentation. The sections were then observed under scanning electron microscope for presence or absence of debris and smear layer and the photographs were taken at coronal, middle and apical 1/3 with a magnification of ~200 and ~1000 respectively. The time taken to enlarge each canal was recorded in minutes and seconds. The instruments were examined after every use for deformation. The scores recorded were statistically analyzed using one.way analysis of variance and Mann.Whitney test.Results: There was statistically significant difference with regard to removal of debris and smear layer at coronal, middle and apical third for LS versus PT and LS versus Ew (P < 0.01). There was no significant difference  between PT and Ew. The mean preparation time for LS, PT and Ew was 1.76, 2.50 and 2.75 respectively. Interpretation and Conclusion: The study demonstrated that, LS instrumentation removed debris and smear layer effectively with shorter preparation time and Ew instrument showed deformation.Key words: Debris, EndoWave, instrument deformation, LightSpeed, nickel-titanium instruments, preparation time, ProTaper, scanning electron microscope analysis, smear laye

An in vitro study of the effect of design of repair surface on the transverse strength of repaired acrylic resin using autopolymerizing resin

Statement of Problem: The fracture of complete denture is a common occurrence in the field of prosthodontics. Often if all other criteria are met such as good aesthetics, occlusion, and functionality; denture repair is acceptable. Once denture fractures, we would want the joint surface strength to be as good as original.Purpose: The purpose of this study was to determine the effect of different repair surface design on the transverse strength of repaired acrylic denture resin.Materials and Methods: Sixty specimens of heat‑cured acrylic resin of dimension 65 mm × 20 mm × 2.5 mm were prepared using a special die. Transverse strength of 15 samples was calculated which serves as a control group. Three different types of joint surface contours were prepared each having 15 samples each as butt, round, and rabbet joint. Transverse strength of three joint contours was then compared with control group and also they were compared with each other and result was statistically analyzed with one‑way analysis of variance (ANOVA) and Post‑hoc ANOVA Tukey’s HSD test at 5% level of significance. Z‑test of proportion was also done for types of failures.Result: Transverse strength of original specimen was higher than that of repaired specimens. Transverse strength of round joint was higher than the butt and rabbet joint.Conclusion: Methods of repair have significant effect on strength of repaired denture. Round joint design of repair technique was far superior.Key words: Autopolymerizing resin, rabbet joint, transverse strengt

Factors affecting Osseointegration: A Literature Review

The purpose of this literature review is to collect the published data concerning factors affecting osseointegration. Popularity and large demand of dental implant makes this study essential because success of dental implant is directly related to the principle of osseointegration, a process of implant-bone interaction that finally leads to bone-implant anchorage.To identify relevant literature an electronic search was performed using term osseointegration and dental implant on PubMed central. Titles and abstracts were screened andarticles that fulfilled the inclusion criteria were selected for full text reading. Review of selected articles enabled us to enlist various factors which have significant effects on osseointegration either by enhancing or inhibiting it. Based on the review literature, it is concluded that there are factors which when considered may increase osseointegrationwhich in turn will increase success of dental implant and some factors play an inhibiting role for bone-implant contact

A comparative study of retention of complete denture base with different types of posterior palatal seals – an in vivo study

GS Chandu,1 BS Hema,2 Harsh Mahajan,1 Antriksh Azad,2 Ipsita Sharma,3 Anurag Azad4 1Department of Prosthodontics, Rishiraj College of Dental Sciences and Research Centre, Bhopal, Madhya Pradesh, India; 2Department of Conservative Dentistry, Rishiraj College of Dental Sciences and Research Centre, Bhopal, Madhya Pradesh, India; 3Department of Oral Pathology, RKDF Dental college and Research centre, Bhopal, Madhya Pradesh, India; 4Department of Oral and Maxillofacial Surgery, Bhabha College of Dental Sciences and Research Centre, Bhopal, Madhya Pradesh, India Aim: To evaluate retention of complete denture base with different types of posterior palatal seals. Material and methods: Ten male patients between the age group of 50 years to 60 years were selected for the study. After the primary and secondary impressions were taken, five casts were made including a cast without posterior palatal seal, a cast with single bead posterior palatal seal, a cast with double bead posterior palatal seal, a cast with butterfly shaped posterior palatal seal, and a cast with posterior palatal seal with low fusing compound by functional method. Results: It was observed that retention increased up to 108% in the posterior palatal seal with low fusing compound with functional method and the posterior palatal seal that was obtained by using functional method provided greater retention than a denture base without posterior palatal seal. Conclusion: It was concluded that the incorporation of a posterior palatal seal is important for obtaining optimum retention of the maxillary complete denture. Keywords: posterior palatal seal, denture base, complete denture, functional metho