Augmented reality in prosthodontics N Gopi Chander The Journal of Indian Prosthodontic Society 2019 19(4):281-282

Evaluation of peri-implant condition in periodontally compromised patients Guilherme Da Rocha Scalzer Lopes, Alfredo Carlos Rodrigues Feitosa, Fabricia Ferreira Suaid, Jefferson David Melo De Matos, John Eversong Lucena De Vasconcelos, Sergio Lins De Azevedo Vaz, Valdir Cabral Andrade, Renato Sussumu Nishioka, Selva Maria Gonçalves Guerra The Journal of Indian Prosthodontic Society 2019 19(4):283-289 Aims: The aim of the study is to evaluate the profile of peri-implant tissues in periodontally compromised patients. Settings and Design: In vivo – cross sectional study design. Materials and Methods: Fifty-eight implants were evaluated, clinically and radiographically, installed in seven individuals treated by the same team of professionals, during the years 1997 and 2005 in a private dental clinic in Vitória, ES, Brazil; that time of data collection, all implants were at least 10 years of functional loading. The variables related to the dental implants evaluated were: visible Plaque Index, Gingival Bleeding Index (GBI), probing pocket depth, bleeding on probing, and bone level, to relate them to the classification of dental implants. Statistical Analysis Used: The Chi-square and Kruskal–Wallis test were adopted. Results: The total of 58 implants were classified: 11 (18.9%) as healthy and 12 (20.7%) as clinically stable. The other 35 implants (60.4%) had some type of peri-implant inflammation, 20 of them (34.5%) were diagnosed with peri-implant mucositis and 15 (25.9%) with peri-implantitis. Among the variables studied, the results showed statistically significant differences for implant location (P = 0.001) and GBI (P = 0.03). Most of the maxillary implants (85.7%) were classified for some type of peri-implant disease. For the implants which resulted in Score 1 for GBI, most of them (75.0%) were also classified for some type of peri-implant disease. Conclusions: Dental implants placed in periodontally compromised patients may have high long-term survival rates. However, most implants were classified with some type of peri-implant inflammation.

A clinical comparative study to assess the efficacy of a new centric registration technique with a conventional technique R Sushma, Malvika Suresh Roy, Pronob Kumar Sanyal, Anand Joshi, Aaditee Vande, Abhijeet Ramachandra Kore The Journal of Indian Prosthodontic Society 2019 19(4):290-295 Aim: The aim and objectives of this study were to assess and compare the efficacy of a new copyrighted technique (wax ball technique, L-77997/2018) and design (denture base design for the wax ball technique, L-78006/2018) for recording centric relation (CR). Settings and Designs: In vivo – comparative study. Materials and Methods: This study was conducted on sixty consented edentulous patients. The study participants were divided into Group I and Group II. CR in Group I patients was recorded using Dawson's bimanual technique (technique 1). For participants in Group II, CR was recorded using the authors' copyrighted technique (technique 2). Time taken and accuracy of CR records by both the techniques were evaluated. Statistical Analysis Used: Descriptive statistics such as frequency and percentage were calculated for categorical variables, mean and standard deviation were calculated for quantitative variables. Independent t-test was used to compare the time taken to record the CR between the two groups. The accuracy of both the techniques was assessed by Mann–Whitney U-test. Results: The mean time taken for technique 1 was 56.47 s, whereas for technique 2, it was 5.97 s, with an overall mean difference of 50.5 s between the two techniques. Both techniques were found to be accurate, as the CR recorded during jaw relation matched with CR during trial in all the cases in both the groups (frequency 30 (N) and cumulative percentage 100%). Conclusion: From the study, it was found that, time taken for technique 2 was statistically less compared to that of technique 1, and both the techniques were found to be equally accurate.

Hard and soft-tissue evaluation of bar-clip, ball-socket, and kerator attachments in mandibular implant overdenture treatment: An in vivo study Nitish Varshney, Sakshi Gupta, Sumit Aggarwal, Shalabh Kumar, M Sadish, Mohsin Khan The Journal of Indian Prosthodontic Society 2019 19(4):296-306 Aim: The aim of this in vivo study was to evaluate and compare the soft and hard tissue changes in implant supported mandibular overdenture with three different attachment system. Settings and Design: In vivo – observation study. Materials and Methods: After evaluation of prosthetic space, fifteen edentulous subjects received two implants in the inter-foramina region of the mandible and were divided into 3 groups with 5 subjects each, delayed loading protocol was followed in all the patients. The crestal bone loss, modified sulcular bleeding index, plaque index values were evaluate with the attachments at baseline and after 6 months was measured in a standardised way. Statistical Analysis Used: Oneway ANOVA test and post hoc Bonferroni multiple test. Results: At the end of six months modified sulcular bleeding index and plaque index values was higher in Group 2 (bar and clip attachment) as compared to Group 1 (ball and socket attachment) and Group 3 (Kerator attachment) and crestal bone loss was equal in groups 1, 2 and 3. Analysis of variance with repeated measures showed significant differences in modified sulcular bleeding index and plaque index among the three attachment types. Conclusion: (1) Group 2 (bar-and-clip attachment) exhibited higher Modified Sulcular Bleeding Index and Plaque Index values than Group 1 (ball-and-socket attachment) and Group 3 (kerator attachment). (2) Crestal bone loss was equal in Group 1 (ball-and-socket attachment), Group 2 (bar-and-clip attachment), and Group 3 (kerator attachment).

Complete denture fracture – A proposed classification system and its incidence in National Capital Region population: A survey Shweta Choudhary The Journal of Indian Prosthodontic Society 2019 19(4):307-312 Aim: The complete denture fracture of denture may ruin the routine life of an edentulous patient. The aim of the present study was to propose and evaluate a new classification system for denture fractures. Settings and Design: Cross sectional -Survey. Materials and Methods: Ten dental laboratories in Delhi and the National Capital Region participated in the study for 2 years. The accurate assessment of fractured dentures received in the laboratories for repairs was done. A questionnaire with complete information along with photographs was used to classify the denture fracture. Statistical Analysis Used: Percentage (proportion) statistical test. Results: Out of 620 dentures, 164 (94 maxillary and 70 mandibular) were found with previous repair, soft liners, metal frame, or wire reinforcements which were excluded from the study. In the present study, 456 dentures were considered (256 maxillary and 200 mandibular). Class I fracture (midline) was the most common in both maxillary and mandibular dentures (46.87% in maxillary and 61% in mandibular) with high significance (P < 0.001). Class II and Class V were the second most common pattern of fracture in mandibular and maxillary dentures, respectively. There was no single case of Class III fracture for the mandibular dentures, and Class IV was the least common among the maxillary dentures. Conclusions: This study encourages further clinical studies for validation and reliability evaluation of proposed new classification system.

A comparative evaluation of amount of gingival displacement produced by four different gingival displacement agents – Anin vivo study Zainab Ilyas Kesari, Jyoti Tipin Karani, Saloni Sharad Mistry, Ashutosh Ramesh Pai The Journal of Indian Prosthodontic Society 2019 19(4):313-323 Aim: The aim of this study was to compare and evaluate the efficacy of ViscoStat clear, Vasozine, and Racegel (with and without cord) with respect to the amount of lateral gingival displacement produced by them. Settings and Design: Comparative - In vivo study. Material and Methods: Thirty consented volunteers were selected in the age group of 18–22 years. Maxillary right first premolar and lateral incisor and maxillary left central incisor and canine were selected for each individual. A composite resin standard reference point was made two millimeters below the gingival margin on the midsection of the labial surface of each tooth. By simple random sampling, the agents (ViscoStat clear, Vasozine, and Racegel with cord and Racegel without cord) were used for gingival displacement on each of the selected teeth. Pre- and postgingival displacement impressions were made with medium-body polyvinyl siloxane impression material. Three-millimeter thick buccolingual slice sections were obtained of the models and measured under a stereo microscope (×20 magnification), and the amount of displacement was calculated. Statistical Analysis used: The Kruskal–Wallis test and the Mann–Whitney U-test were used for comparison between the amounts of gingival displacement produced by them. Results: Mean displacement produced (in mm2) by Racegel with cord, tetrahydrozoline, ViscoStat clear, and Racegel is 0.2256, 0.2158, 0.2069, and 0.1414, respectively. Conclusions: The largest mean gingival displacement was produced by Racegel with cord (0.2256 mm2) and lowest by Racegel without cord (0.1414 mm2). There was no significant statistical difference in the amount of gingival displacement produced between the four agents.

Comparison of expectation and satisfaction among new and existing denture wearers and correlation of duration of previous denture-wearing experience to satisfaction in completely edentulous patients: A pilot study Deepa Subramanian, Raj Tilak Govindarajulu, Vinod Narayanan, Nandhini Devi Kalimuthu The Journal of Indian Prosthodontic Society 2019 19(4):324-331 Aim: The aim of the study was to evaluate the patients' expectation and satisfaction with complete dentures before and after the treatment concerning retention, mastication, phonetics, esthetics, and comfort among the first-time denture wearers and already denture wearers and to find the correlation between duration of denture-wearing experience and satisfaction. Settings and Design: Cross sectional survey . Materials and Methods: A questionnaire was given to the patient before the onset of the treatment, and ratings were given by the patient for expectation regarding retention, mastication, phonetics, esthetics, and comfort. Patient-related variables regarding previous denture experience and duration of wearing were also recorded. After the treatment was completed, the patient was asked to complete the same questionnaire to assess the satisfaction. Statistical Analysis Used: Descriptive statistics, frequency and percentage analysis, Wilcoxon signed- rank test, Mann–Whitney U-test. Results: Expectation and satisfaction were met for all the variables except mastication (P = 0.004) for first-time wearers and except mastication (P = 0.001) and comfort (P = 0.007) among existing denture wearers. However, no significant correlation was elicited between patient expectation and satisfaction in both these groups as the overall mean satisfaction percentage was similar. A clinical significance of P = 0.037 was seen with respect to the duration of denture-wearing experience among existing wearers. Regression model analysis showed a decreased satisfaction with increased duration of wearing (r = 0.396). Conclusions: Satisfaction and expectation were found to be almost the same irrespective of whether they are first-time wearers or existing wearers. With the increase in the duration of denture-wearing experience, the satisfaction of the patients decreased.

Evaluation of cytotoxicity levels of poly vinyl ether silicone, polyether, and poly vinyl siloxane impression materials: An in vitro study N Vivek Rajasimhan, Srinivasan Jayaraman, Doulathunnisa Jaffar Ali, Balanehru Subramanian The Journal of Indian Prosthodontic Society 2019 19(4):332-337 Aim: To assess the cytotoxicity level of newly introduced poly vinyl ether silicone (PVES) compared to poly vinyl siloxane (PVS) and polyether (PE) elastomeric impression materials. Settings and Design: Comparative -Invitro study design. Materials and Methods: Mouse cell line NIH/3T3 was grown in Dulbecco's modified Eagle's medium. Samples of three elastomers were dissolved in dimethyl sulfoxide and were tested at various concentrations. Twenty-four well plates with NIH/3T3 cells with different concentrations of elastomeric solutions were incubated at 37°C. 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide assay was performed on day 1, 3, and 7, with a time interval of 15 min, 30 min, 60 min, and 24th h to estimate the cytotoxicity for all three elastomers. Statistical Analysis Used: Kruskal–Wallis ANOVA test and the period effect within the subjects, repeated-measure ANOVA was done using the Greenhouse–Geisser correction method. Results: The mean cell viability (survival rate) of NIH 3T3 cells at the concentrations tested was measured. A repeated-measure Kruskal–Wallis ANOVA determined the mean survival concentration on day 1, 3, and 7. PVES showed significant decrease in the survival rate on day 1 than PVS and PE, while PVS and PE had significant decrease in the survival rates of cells on day 3 and 7 which were statistically significant (P < 0.001). Conclusion: PVES shows early cytotoxic signs as compared to PVS and PE, and cell viability for PVS was the highest among all. When making impression with PVES and PE, it is always better to evaluate the impression and gingival sulcus carefully with magnification to prevent adverse reaction, if any material is left inadvertently for longer period of time.

A comparative evaluation of the effect of liners on the shear bond strength of veneered zirconia block: An in vitro study Pooja Yadav, Nupur Dabas, Sumit Singh Phukela, Puja Malhotra, Shefali Drall, Pankaj Kumar Ritwal The Journal of Indian Prosthodontic Society 2019 19(4):338-344 Aim: This study aims to evaluate the effect of lithium disilicate glass–ceramic liner, silicon dioxide based liner, and glass–ceramic interlayer on the shear bond strength (SBS) of a commercially available veneered zirconia block and to study fractographic behavior of the samples using universal testing machine, scanning electron microscope (SEM). Setting and Design: In vivo – comparative study. Materials and Methods: 60 samples were fabricated from VITA (vita zahnfabrik. Bad sackingen, Germany) zirconia discs. Samples were divided into 4 groups with 15 samples each. First is the control group, second is lithium disilicate glass–ceramic liner group, third is silicon dioxide based liner, and fourth is glass–ceramic interlayer group. SBS of samples was recorded using universal testing machine. Samples were further analyzed for fractographic behavior using SEM. Statistical Analysis Used: One Way ANOVA test, and Chi-Square test. Results: The intergroup comparison of mean SBS (Mpa) was done using the post hoc Bonferroni test. The mean SBS (Mpa) was significantly more among lithium disilicate and glass–ceramic interlayer groups in comparison to silicon dioxide-based liner group. Fractographic analysis was done using the Chi-square test. Conclusion: It was concluded that maximum SBS was obtained for lithium disilicate liner. Maximum adhesive failures were found with lithium disilicate liner, and silicon dioxide-based liner group showed cohesive failures.

Comparative evaluation of elastic recovery of three different elastomeric impression materials on chemical disinfection and autoclaving: An in vitro study Garima Gothwal, Sudhir Meena, U Narendra Padiyar, Hemant Kumar Sharma, Pragati Kaurani, Devendra Pal Singh The Journal of Indian Prosthodontic Society 2019 19(4):345-352 Aim: The aim of the study was to investigate the effect of disinfection and steam autoclaving on the elastic recovery of three different elastomeric impression materials. Settings and Design:In vivo - comparative study. Materials and Methods: Ninety dumbbell-shaped specimens of commercially available two addition-cured silicones (AFFINIS and AQUASIL) and one condensation-cured silicone (SPEEDEX) impression materials were prepared and treated with chemical disinfectant and steam autoclaving. Specimens were seal packed and sent to laboratory for testing elastic recovery. After the specimen had been pulled to failure, the broken parts were fitted back together, and the distance between the marks was measured using an electronic Vernier caliper. Statistical Analysis Used: one-way analysis of variance test and Tukey post hoc test for multiple comparisons. Results: The result showed significant difference in elastic recovery of AFFINIS when it was disinfected and steam autoclaved whereas elastic recovery showed no significant difference when SPEEDEX and AQUASIL were disinfected and steam autoclaved. Similarly, results were alike when AFFINIS, SPEEDEX, and AQUASIL were compared on disinfection. However, significant difference was noted on steam autoclaving, highest being the mean value of AFFINIS. Conclusion: Within the limitations of this in vitro study, conclusion was made that the elastic recovery of AFFINIS was the least which improved with disinfection and autoclaving. Elastic recovery of SPEEDEX and AQUASIL was similar. However, all the three materials used in the study can be safely sterilized after clinical use and before being sent to the laboratory without significantly affecting their elastic recovery.