Evaluation of microneedling with and without injectable-platelet rich fibrin for gingival augmentation in thin gingival phenotype-A randomized clinical trial

Objective

The purpose of the current study was to investigate the effect of micro needling (MN) on gingival thickness (GT) and keratinized tissue width (KTW) in individuals with thin gingival phenotypes, either with or without injectable platelet-rich fibrin (i-PRF).

Materials and methods

In this randomized, split-mouth clinical trial, 15 systemically healthy patients, with thin gingival phenotype (<1.5 mm) were randomly treated with MN + i-PRF and MN. MN was performed on one side, and MN + i-PRF on the contralateral side of the same arch at 4 sessions with 10-day intervals. GT; KTW the primary outcome and Plaque index; gingival index Secondary outcome were assessed at baseline and at 1st, 3rd, and 6th months post-treatment.

Results

The results of the present study showed that both techniques demonstrated a statistically significant increase in GT. GT showed a statistically significant increase from baseline (0.453 ± 0.069 mm in MN, 0.451 ± 0.069 mm in MN + i-PRF) (p = 0.81) to 1 month (0.567 ± 0.075 mm in MN, 0.649 ± 0.075 mm in MN + i-PRF) (p < 0.001*). A follow-up at 3rd month (0.566 ± 0.076 mm in MN, 0.647 ± 0.091 mm in MN + i-PRF) (p < 0.001*) and 6th month (0.564 ± 0.076 mm in MN, 0.644 ± 0.089 mm in MN + i-PRF) (p < 0.001*) showed a statistically significant increase. Intergroup comparison showed a statistically significant GT increase in MN + i-PRF sites at all the time intervals. No, statistically significant difference in KTW was observed in both groups from baseline to 6 months.

Conclusions

The utilization of MN + i-PRF stands as a minimally invasive, non-surgical method to improve GT. Interestingly, using i-PRF as an additional component demonstrated more favorable outcomes compared to using MN alone in enhancing tissue thickness.

Maxillary Sinus Floor Augmentation With Allograft Alone Compared With Alternate Grafting Materials: A Systematic Review and Meta-Analysis

A meta-analysis of scientific literature was conducted to ascertain the superiority between allografts and other regenerative grafts for maxillary sinus floor augmentation (MSFA). Review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and registered in PROSPERO-CRD42023392766. Electronic databases like PubMed, Google scholar and Ebsco Host were searched from 2000 to December 2022 for studies reporting MSFA using allografts or other regenerative grafts. Quality assessment of included studies was evaluated using the Cochrane risk of bias (ROB)-2 tool for randomized controlled trials through its domains. Risk of bias summary graph and ROB summary applicability concern were plotted using RevMan software version 5.3. The standardized mean difference was used as a summary statistic measure with random effect model and P value <0.05 as statistically significant. Four studies fulfilled the eligibility criteria and were included in qualitative synthesis, of which all 4 studies were suitable for meta-analysis. Pooled estimate through standardized mean difference signifies that new bone formation was more or less similar for both graft materials, whereas regenerative grafts showed more residual bone grafts (P>0.05). Publication bias through funnel plot showed symmetric distribution with the absence of systematic heterogeneity. Both allografts and other regenerative grafts are equally effective in the MSFA in terms of new bone formation, whereras regenerative grafts showed more residual bone grafts. Furthermore, randomized controlled trials are required to establish evidence in outcomes involving sinus floor augmentation and different graft materials.

Micro-treatment options for components of organic fraction of MSW in residential areas

There is a growing interest in management of MSW through micro-treatment of organic fraction of municipal solid wastes (OFMSW) in many cities of India. The OFMSW fraction is high (>80%) in many pockets within South Indian cities like Bangalore, Chikkamagalur, etc. and is largely represented by vegetable, fruit, packing and garden wastes. Among these, the last three have shown problems for easy decomposition. Fruit wastes are characterized by a large pectin supported fraction that decomposes quickly to organic acids (becomes pulpy) that eventually slow down anaerobic and aerobic decomposition processes. Paper fraction (newsprint and photocopying paper) as well as paddy straw (packing), bagasse (from cane juice stalls) and tree leaf litter (typical garden waste and street sweepings) are found in reasonably large proportions in MSW. These decompose slowly due to poor nutrients or physical state. We have examined the suitability of these substrates for micro-composting in plastic bins by tracking decomposition pattern and physical changes. It was found that fruit wastes decompose rapidly to produce organic acids and large leachate fraction such that it may need to be mixed with leachate absorbing materials (dry wastes) for good composting. Leaf litter, paddy straw and bagasse decompose to the tune of 90, 68 and 60% VS and are suitable for composting micro-treatment. Paper fractions even when augmented with 10% leaf compost failed to show appreciable decomposition in 50 days. All these feedstocks were found to have good biological methane potential (BMP) and showed promise for conversion to biogas under a mixed feed operation. Suitability of this approach was verified by operating a plug-flow type anaerobic digester where only leaf litter gathered nearby (as street sweepings) was used as feedstock. Here only a third of the BMP was realized at this scale (0.18 m(3 )biogas/kg VS 0.55 m(3)/kg in BMP). We conclude that anaerobic digestion in plug-flow like digesters appear a more suitable micro-treatment option (2-10 kg VS/day) because in addition to compost it also produces biogas for domestic use nearby.

Biochemical characterization of the intracellular domain of the human guanylyl cyclase C receptor provides evidence for a catalytically active homotrimer

Guanylyl cyclase C (GCC) is the receptor for the family of guanylin peptides and bacterial heat-stable enterotoxins (ST). The receptor is composed of an extracellular, ligand-binding domain and an intracellular domain with a region of homology to protein kinases and a guanylyl cyclase catalytic domain. We have expressed the entire intracellular domain of GCC in insect cells and purified the recombinant protein, GCC-IDbac, to study its catalytic activity and regulation. Kinetic properties of the purified protein were similar to that of full-length GCC, and high activity was observed when MnGTP was used as the substrate. Nonionic detergents, which stimulate the guanylyl cyclase activity of membrane-associated GCC, did not appreciably increase the activity of GCC-IDbac, indicating that activation of the receptor by Lubrol involved conformational changes that required the transmembrane and/or the extracellular domain. The guanylyl cyclase activity of GCC-IDbac was inhibited by Zn(2+), at concentrations shown to inhibit adenylyl cyclase, suggesting a structural homology between the two enzymes. Covalent cross-linking of GCC-IDbac indicated that the protein could associate as a dimer, but a large fraction was present as a trimer. Gel filtration analysis also showed that the major fraction of the protein eluted at a molecular size of a trimer, suggesting that the dimer detected by cross-linking represented subtle differences in the juxtaposition of the individual polypeptide chains. We therefore provide evidence that the trimeric state of GCC is catalytically active, and sequences required to generate the trimer are present in the intracellular domain of GCC.