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Introduction: Yttria stabilised tetragonal zirconia opens new vistas for all ceramic restoration by the mechanism of transformation toughening, making it much stronger compared to all other ceramic materials. Currently, it is the most recent core material for all ceramic fixed partial dentures due to its ability to withstand high simulated masticatory loads. Problems which have been reported with zirconia restorations involve the core cement interface leading to loss of retention of the prosthesis. Different reasons which have been reported for the same include the lack of adhesion between zirconia and commonly used cements due to absence of silica phase which makes zirconia not etchable. In addition, the hydrophobic nature of zirconia causes low wettability of zirconia surface by the adhesive cements which are commonly used., Aim: The purpose of this in vitro study was to compare and evaluate the effect of two pre-treatments of zirconia, using plasma of argon and silane, on the shear bond strength values of two composite resin cements to zirconia and to evaluate the failure pattern of the debonded areas using stereomicroscopic analysis., Materials and Methods: Sixty zirconia discs (10 mm×2 mm) were randomly divided into three groups (n=20), following surface treatment, with airborne particle abrasion, using 110 µm Al2O3: Group I (control), Group II (plasma of argon cleaning), and Group III (application of silane primer). Each group had two subgroups based on the type of resin cement used for bonding: subgroup A; Rely X Ultimate (3M ESPE) and subgroup B; Panavia F (Kuraray). In subgroup A, Rely X universal silane primer and in subgroup B Clearfil ceramic primer was used. Shear bond strengths were determined after water storage for one day and thermocycling for 5000 cycles. Data (megapascal) were analyzed using ANOVA and Bonferroni test. Specimens were subjected to stereomicroscopic analysis, for evaluation of failure pattern., Results: Group III produced the highest shear bond strength followed by Group II and Group I. Subgroup A showed higher shear bond strength than Subgroup B. Stereomicroscopic analysis showed cohesive failure in Group III, while in Group I adhesive failure was seen., Conclusion: Silane primer application caused maximum increase in shear bond strength due to increased wettability. Argon plasma treatment was less effective in comparison to silane treatment. Air abrasion when used alone resulted in lower bond strength values, thereby making it necessary to use a combination of surface treatments. Rely X Ultimate cement was superior to Panavia F in terms of adhesive bonding to zirconia.

Patient: This report describes the case of a 68 year old female patient who presented with the chief complaint of difficulty in chewing and poor aesthetics due to missing teeth. The patient was interested in saving the remaining natural teeth and desired minimal tissue coverage from the prosthesis. After consideration of all the factors involved, it was deemed advisable to resort to a palate free maxillary telescopic complete denture and a mandibular removable partial denture., Discussion: Considering the age of the patient and the cost involved, implant supported prosthesis was ruled out as a treatment option for the patient. A telescopic denture was chosen as a favourable treatment option since it overcomes many of the problems posed by conventional complete dentures like progressive bone loss, lower stability and retention, loss of periodontal proprioception and low masticatory efficiency. It also provides minimal tissue coverage and better distribution of forces. Evaluation of occlusion, esthetics, phonetics and comfort after 24 hours, 1 week and 1 month of treatment showed that the patient was happy with the prosthesis and was able to speak and chew well., Conclusion: Telescopic overdentures have better retention and stability as compared to conventional complete dentures. They improve the chewing efficiency, patient comfort and also decrease the alveolar bone resorption. As such they are an excellent alternative to conventional complete denture treatment.

One of the main objectives of the forensic sciences is establishing a person's identity which can be a very complex process. The analysis of the teeth, fingerprints and DNA evaluation are probably the most used techniques allowing fast and secure identification processes. Palatal rugae or transverse palatine folds are asymmetrical and irregular elevations of the mucosa located in the anterior third of the palate and are permanent, prominent and unique for individuals and thus can be used as identification for forensic purposes widely in edentulous patients wherein no teeth are present in the oral cavity. In forensic odontology dentists play a prime role in supporting legal and criminal issues. Palatoscopy or palatal rugoscopy is the name given to the study of palatal rugae in order to ascertain a person's identity. Studies have demonstrated that no two individual rugae patterns are alike in their configuration and the characteristic rugae pattern of the palate does not change as a result of growth. Hence this article reviews the significance of palatal rugae patterns in edentulous cases as a reliable forensic marker.

Background: Implant treatment is today a common and most widely accepted prosthetic therapy worldwide. The quality and quantity of the bone available at the anticipated implant site is of prime importance. Accurate measurement of alveolar bone and adjacent anatomic structures are of paramount importance in implant insertion. Proper pre-surgical assessment requires precise radiographic visualization of anatomic structures and pathologic conditions. However, the concern for radiation exposure has also grown., Materials and Methods: A total of 15 partially or completely edentulous human cadaveric mandibles were used which were further subdivided into three further groups for cone-beam computed tomography (CBCT), orthopantomography (OPG), and direct measurements (DM). Mandibles were prepared for each sample and subjected to radiographs according to the respective techniques, and radiographic measurements were done using the appropriate software. The cadaveric mandibles were then sectioned, and the actual measurements were done using a digital vernier caliper., Results: Analysis of variance test revealed that there was no significant difference among the three different measurements techniques., Conclusion: A sizable portion of the CBCT measurements with respect to width showed slight overestimation when compared to DMs. There were no statistically significant differences found between CBCT, OPG, and DM when height was taken into consideration.

The main objective of the study was to recognize the effect of ceramic thickness and luting agent on the extent to which the restoration masks color variations that may be present in the underlying dental structure. Two pressable ceramics were used: Lithium disilicate reinforced (IPS e.max- Ivoclar Vivadent) and Leucite reinforced (Cergo- Dentsply). Fifteen ceramic discs were manufactured from each ceramic and divided into three groups, according to the thickness (0.5, 1, 1.5 mm). To simulate the color of a dark underlying dental structure, background discs, color C3, with 20 mm diameter, were made using resin composite. The ceramic discs with varying thicknesses were seated on the dark background of the resin composite with either resinous opaque cement or resinous cement. The color parameters were determined by the CIE Lab system of colors using a spectrophotometer and color differences (ΔE) were calculated. The results were then statistically analyzed, using ANOVA test and Tukey HSD test. The ΔE values of both ceramic systems were affected by both the luting agent and the ceramic thickness (P < 0.05). The use of an opaque luting agent resulted in an increase of the ΔE* values for all ceramics tested, regardless of the thickness. For the 1.5-mm thick veneers, higher values in the color parameters were obtained for both ceramic materials. The color masking ability of ceramics used for laminate veneers is significantly affected by the thickness of the ceramic and the shade of the luting agent used.