Nevin Manimala

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):74-80. doi: 10.4103/jips.jips_297_20.

ABSTRACT

AIMS: The study compared changes in implant stability and bone loss of implants with different designs using early loading at 6 weeks.

SETTING AND DESIGN: In vivo-comparative study.

MATERIALS AND METHODS: Forty subjects were selected and divided randomly by sealed envelope method in Group X and Group A for early loading for missing single posterior tooth in mandible. Implants in Group X had flared crest module and buttress thread design, whereas implants in Group A had parallel crest module and V-shaped thread design. All subjects were evaluated by Ostell for implant stability at the interval of baseline, 6 weeks, 3 months, and 6 months. ImageJ software was used for measurement of crestal bone loss in intraoral periapical radiographs at the interval of 6 weeks, 3 months, and 6 months.

STATISTICAL ANALYSIS USED: Unpaired t test, repeated ANOVA, Tukey post hoc test.

RESULTS: The mean bone loss values of Group X at predetermined interval were 1.51 ± 0.20 mm, 2.11 ± 0.21 mm and 2.13 ± 0.21 mm. The mean bone loss values of Group A were 1.79 ± 0.16 mm, 2.92 ± 0.23 mm and 2.95 ± 0.23 mm. The mean bone loss was statistical significant (P < 0.05) at 6 weeks, 3 months and 6 months. It was highly significant in Group A at 6 months (P < 0.001).

CONCLUSIONS: It was concluded that Group X implants design showed better implant stability and less bone loss when compared to Group A implants design.

PMID:33835071 | DOI:10.4103/jips.jips_297_20

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):66-73. doi: 10.4103/jips.jips_303_20.

ABSTRACT

AIM: To evaluate anxiety in patients undergoing complete denture treatment.

SETTINGS AND DESIGN: The most overlooked factor during complete denture treatment is the patient’s anxiety regarding the treatment. The awareness amongst dentists regarding such anxiety and its effects on the complete denture treatment is important to form a proper communication channel through which measures to ease this anxiety can be formulated and implemented.

MATERIALS AND METHODS: A valid pre-structured questionnaire of 10 questions was presented to the patients desirous of receiving complete dentures after obtaining an informed consent. The questionnaire for the survey was filled and collected from 500 patients receiving complete denture treatment.

STATISTICAL ANALYSIS USED: Descriptive statistics.

RESULTS: Reasons inducing anxiety included: materials used – 359 (71.8%), sight of instruments – 71 (14.2%), dental chair – 66 (13.2%), airotor – 4 (0.8%), denture breakage – 225 (45.0%), ill-fitting prostheses – 153 (30.6%), repeated removal and insertion of dentures 104 (20.8%), swallowing the denture 19 (3.8%). Factors aggravating anxiety included: gagging while impression making – 298 (59.6%), mouth fullness – 122 (24.4%), swallowing the impression material – 61 (12.2%), breathlessness – 20 (4%). 422 (84.4%) patients indicated comfort with the procedure being explained beforehand, 429 (85.8%) patients indicating more so in a language understood by them.

CONCLUSION: There is a greater need that the patient’s expectations be understood and their doubts, concerns and fears be lessened by proper communication. Proper understanding of patient’s mental attitude will help us improve the approach of dentists towards complete denture treatment in a more patient friendly way.

PMID:33835070 | DOI:10.4103/jips.jips_303_20

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):57-65. doi: 10.4103/jips.jips_19_20.

ABSTRACT

AIM: To evaluate the microleakage of metallic copings luted with three different commercially available luting cements.

SETTING AND DESIGN: Comparative evaluation in vitro study.

MATERIALS AND METHODS: Thirty replicas of abutment analog were milled and divided into 3 groups. Nickel chromium copings were fabricated; marginal gap was evaluated with optical microscope and luted with Zinc Oxide Non Eugenol cement, Zinc Polycarboxylate cement and Zinc Phosphate cement. After Thermocycling, cemented specimens were placed into 0.5% aqueous solution of basic fuchsin solution for 24 hours for dye penetration. Copings were longitudinally sectioned and microleakage scores were evaluated.

STATISTICAL ANALYSIS USED: Kruskal-Wallis analysis of variance (ANOVA) followed by Chi-Square test. Pairwise comparison of groups with Mann Whitney U test.

RESULT: Mean microleakage score was least for Zinc Phosphate cement (1.075 ± 0.85) followed by Zinc Polycarboxylate cement (1.80± 0.23) and most for Zinc Oxide Non Eugenol (2.1± 0.37). The results of the study were statistically significant, P < 0.05.

CONCLUSIONS: Within the limitations of the study, it was found that all cements exhibited certain amount of microleakage. Zinc Phosphate cement exhibited a mean microleakage score that was significantly lower than Zinc Oxide Non Eugenol cement and Zinc Polycarboxylate cement. When microleakage scores of Zinc Oxide Non Eugenol cement and Zinc Polycarboxylate cement were compared, the difference was found to be insignificant indicating that microleakage in these cements is similar.

PMID:33835069 | DOI:10.4103/jips.jips_19_20

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):50-56. doi: 10.4103/jips.jips_284_20.

ABSTRACT

AIM: The objective is to evaluate the effect of shades of monolithic zirconia on the microhardness and sorption/solubility of the underlying two dual-cured resin types of cement.

MATERIALS AND METHODS: Eighty samples of two dual-cured resin cement discs were polymerized under 60 monolithic zirconia discs in three shades and directly activated resin discs of cement were used as the control group (n = 10). After 24 h storage at 37°C in an incubator, Vickers microhardness and the sorption and solubility were measured.

STATISTICAL ANALYSIS USED: Two-way ANOVA , one-way ANOVA, Independent t-test, Tukey’s honestly significant difference, and Tamhane’s T2 tests.

RESULTS: The mean microhardness of the Variolink N resin cements were significantly higher than Panavia SA ones (P < 0.001). Furthermore, Variolink N cements exhibited lower sorption/solubility than Panavia SA resin cements (both P < 0.05). The ceramic shade had a significant influence on the microhardness of both cements (P < 0.001) but had no significant effect on the sorption/solubility of resin cements (P > 0.05).

CONCLUSION: Interposition of monolithic zirconia decreases the microhardness of resin cement especially Panavia SA. In Variolink N, by increasing the chroma saturation of ceramics, the microhardness decreased, however in Panavia SA, it was altered by the shades, but not in a specific pattern. For both cements, there were no statistical differences between the sorption/solubility of samples photo-cured under different shades. There was a reverse correlation between microhardness and water sorption/solubility of both cements.

PMID:33835068 | DOI:10.4103/jips.jips_284_20

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):45-49. doi: 10.4103/jips.jips_252_20.

ABSTRACT

AIM: To compare the rise in temperature using trephines over conventional ones during bone site preparation.

SETTING AND DESIGN: An-vitro, evaluative study.

MATERIALS AND METHODS: Twenty implant sites were prepared using pilot drill up to depth of 10 mm on bovine femoral bone. In first part, no irrigation was used. Five sites were prepared using conventional drill of 2.8 mm, and other five were prepared with help of trephine drills. On completion of each drill, infrared thermometer was used to measure temperature on both the drill tip and the shaft. The same procedure was repeated with bone immersed in saline.

STATISTICAL ANALYSIS USED: Student t test was used to evaluate the significance of difference.

RESULT: Study showed that the temperature rise at drill tip was significantly higher for trephine drill (52.98 ± 1.67 °C) than conventional drills (48.20 ± 0.67 °C), however the temperature difference in trephine and conventional drills was statistically insignificant.

CONCLUSION: The temperature increase was more distributed in conventional drills than trephine. Copious irrigation is thus mandatory for trephine drills. Intermittent drilling is preferred with conventional drills.

PMID:33835067 | DOI:10.4103/jips.jips_252_20

J Indian Prosthodont Soc. 2021 Jan-Mar;21(1):28-44. doi: 10.4103/jips.jips_400_20.

ABSTRACT

AIM: The purpose of systematic review and meta-analysis was to compare the efficacy of short implant versus conventional long implant with sinus graft in patients rehabilitated for posterior atrophic maxilla.

SETTING AND DESIGN: Systematic review and meta analysis.

MATERIALS AND METHODS: Electronic searches were conducted in Pub Med, Embase, and Medline with supplemented by manual search up to December 2019. The randomized controlled trial (RCTs) comparing short implant (<8.5 mm) and long implant (>8.5 mm) with sinus graft were included. (Prospero CRD42020186972).

STATISTICAL ANALYSIS USED: Random-effect model, fixed-effect model, A funnel plot and the Egger’s test.

RESULTS: Twenty-two Randomized controlled trials (RCTs) were assessed with 667 patients and 1595 implants (short implant:767, Long implant:835). No significant difference of implant survival rate was recorded for short and long implant (at patient level: RR: 1.01, 95% CI = 0.52-2.0, P = 0.87, I² = 0%, at implant level RR = 1.09, 95% CI = 0.6-2.0, P = 0.7, I² = 0%). Similarly marginal bone resorption was reported no difference for short and long implant (MD = 0.16. 95% CI: -0.23 = -0.08, P = 0.00, I2 = 74.83%). Biological complications were marginally higher for long implant (RR = 0.48, 95% CI = 0.23-0.8, P = 0.13, I² = 29.11%). and prosthetic complications were marginally higher for short implants (RR=1.56, 95% CI=0.85-3.15, P = 0.43, I² = 0%).

CONCLUSION: There was no significance difference in implant survival rate and marginal bone resorption recorded for both the short implant and long implant with sinus graft, in the patients rehabilitated with posterior atrophic maxilla. Hence, short implant is a suitable alternative to long implant with sinus graft, for the rehabilitation posterior atrophic maxilla.

PMID:33835066 | DOI:10.4103/jips.jips_400_20

Sci Rep. 2021 Apr 8;11(1):7769. doi: 10.1038/s41598-021-87064-7.

ABSTRACT

Automated machine learning approaches to skin lesion diagnosis from images are approaching dermatologist-level performance. However, current machine learning approaches that suggest management decisions rely on predicting the underlying skin condition to infer a management decision without considering the variability of management decisions that may exist within a single condition. We present the first work to explore image-based prediction of clinical management decisions directly without explicitly predicting the diagnosis. In particular, we use clinical and dermoscopic images of skin lesions along with patient metadata from the Interactive Atlas of Dermoscopy dataset (1011 cases; 20 disease labels; 3 management decisions) and demonstrate that predicting management labels directly is more accurate than predicting the diagnosis and then inferring the management decision ([Formula: see text] and [Formula: see text] improvement in overall accuracy and AUROC respectively), statistically significant at [Formula: see text]. Directly predicting management decisions also considerably reduces the over-excision rate as compared to management decisions inferred from diagnosis predictions (24.56% fewer cases wrongly predicted to be excised). Furthermore, we show that training a model to also simultaneously predict the seven-point criteria and the diagnosis of skin lesions yields an even higher accuracy (improvements of [Formula: see text] and [Formula: see text] in overall accuracy and AUROC respectively) of management predictions. Finally, we demonstrate our model’s generalizability by evaluating on the publicly available MClass-D dataset and show that our model agrees with the clinical management recommendations of 157 dermatologists as much as they agree amongst each other.

PMID:33833293 | DOI:10.1038/s41598-021-87064-7

Sci Rep. 2021 Apr 8;11(1):7783. doi: 10.1038/s41598-021-87087-0.

ABSTRACT

Self-assembling processes are ubiquitous phenomena that drive the organization and the hierarchical formation of complex molecular systems. The investigation of assembling dynamics, emerging from the interactions among biomolecules like amino-acids and polypeptides, is fundamental to determine how a mixture of simple objects can yield a complex structure at the nano-scale level. In this paper we present HyperBeta, a novel open-source software that exploits an innovative algorithm based on hyper-graphs to efficiently identify and graphically represent the dynamics of [Formula: see text]-sheets formation. Differently from the existing tools, HyperBeta directly manipulates data generated by means of coarse-grained molecular dynamics simulation tools (GROMACS), performed using the MARTINI force field. Coarse-grained molecular structures are visualized using HyperBeta ‘s proprietary real-time high-quality 3D engine, which provides a plethora of analysis tools and statistical information, controlled by means of an intuitive event-based graphical user interface. The high-quality renderer relies on a variety of visual cues to improve the readability and interpretability of distance and depth relationships between peptides. We show that HyperBeta is able to track the [Formula: see text]-sheets formation in coarse-grained molecular dynamics simulations, and provides a completely new and efficient mean for the investigation of the kinetics of these nano-structures. HyperBeta will therefore facilitate biotechnological and medical research where these structural elements play a crucial role, such as the development of novel high-performance biomaterials in tissue engineering, or a better comprehension of the molecular mechanisms at the basis of complex pathologies like Alzheimer’s disease.

PMID:33833280 | DOI:10.1038/s41598-021-87087-0

Sci Rep. 2021 Apr 8;11(1):7806. doi: 10.1038/s41598-021-86937-1.

ABSTRACT

In this study, statistical analysis and spatial distribution were performed to compare raw data and centred log-ratio (clr) transformed data of three copper (Cu), lead (Pb), and zinc (Zn) potentially toxic elements (PTEs) concentration for 550 surface soil samples in Khuzestan plain. The results of both approaches showed that classical univariate analysis and compositional data analysis are essential to find the real structure of data and clarify its different aspects. Results also indicated that spatial distributions of raw data and clr-transformed data were completely different in three studied metals. Raw data necessarily shows the effects of anthropogenic activities and needs an additional evaluation of human health risk assessment for these three studied elements. Data obtained from clr-coefficient maps also demonstrated the role of geological processes in the distribution pattern of potentially toxic elements (PTEs). To improve the understanding of the implications for PTE pollution and consequences for human health, a RGB colour composite map was produce to identify the potential origin of PTEs from areas with higher than typical baseline concentrations.

PMID:33833253 | DOI:10.1038/s41598-021-86937-1

Nat Commun. 2021 Apr 8;12(1):2106. doi: 10.1038/s41467-021-22241-w.

ABSTRACT

Data availability and temporal resolution make it challenging to unravel the anatomy (duration and temporal phasing) of the Last Glacial abrupt climate changes. Here, we address these limitations by investigating the anatomy of abrupt changes using sub-decadal-scale records from Greenland ice cores. We highlight the absence of a systematic pattern in the anatomy of abrupt changes as recorded in different ice parameters. This diversity in the sequence of changes seen in ice-core data is also observed in climate parameters derived from numerical simulations which exhibit self-sustained abrupt variability arising from internal atmosphere-ice-ocean interactions. Our analysis of two ice cores shows that the diversity of abrupt warming transitions represents variability inherent to the climate system and not archive-specific noise. Our results hint that during these abrupt events, it may not be possible to infer statistically-robust leads and lags between the different components of the climate system because of their tight coupling.

PMID:33833238 | DOI:10.1038/s41467-021-22241-w