The Neuropeptide α-Melanocyte-Stimulating Hormone Prevents Persistent Corneal Edema following Injury.

Corneal endothelial cells (CEnCs) regulate corneal hydration and maintain tissue transparency through their barrier and pump function. However, these cells exhibit limited regenerative capacity following injury. Currently, corneal transplantation is the only established therapy for restoring endothelial function, and there are no pharmacologic interventions available for restoring endothelial function. This study investigated the efficacy of the neuropeptide α-melanocyte-stimulating hormone (α-MSH) in promoting endothelial regeneration during the critical window between ocular injury and the onset of endothelial decompensation using an established murine model of injury using transcorneal freezing. Local administration of α-MSH following injury prevented corneal edema and opacity, reduced leukocyte infiltration, and limited CEnC apoptosis while promoting their proliferation. These results suggest that α-MSH has a proregenerative and cytoprotective function on CEnCs and shows promise as a therapy for the prevention and management of corneal endothelial dysfunction.

Rapid Peptide Cyclization Inspired by the Modular Logic of Nonribosomal Peptide Synthetases.

Nonribosomal cyclic peptides (NRcPs) are structurally complex natural products and a vital pool of therapeutics, particularly antibiotics. Their structural diversity arises from the ability of the multidomain enzyme assembly lines, nonribosomal peptide synthetases (NRPSs), to utilize bespoke nonproteinogenic amino acids, modify the linear peptide during elongation, and catalyze an array of cyclization modes, e.g., head to tail, side chain to tail. The study and drug development of NRcPs are often limited by a lack of easy synthetic access to NRcPs and their analogues, with selective macrolactamization being a major bottleneck. Herein, we report a generally applicable chemical macrocyclization method of unprecedented speed and selectivity. Inspired by biosynthetic cyclization, it combines the deprotected linear biosynthetic precursor peptide sequence with a highly reactive C-terminus to produce NRcPs and analogues in minutes. The method was applied to several NRcPs of varying sequences, ring sizes, and cyclization modes including rufomycin, colistin, and gramicidin S with comparable success. We thus demonstrate that the linear order of modules in NRPS enzymes that determines peptide sequence encodes the key structural information to produce peptides conformationally biased toward macrocyclization. To fully exploit this conformational bias synthetically, a highly reactive C-terminal acyl azide is also required, alongside carefully balanced pH and solvent conditions. This allows for consistent, facile cyclization of exceptional speed, selectivity, and atom efficiency. This exciting macrolactamization method represents a new enabling technology for the biosynthetic study of NRcPs and their development as therapeutics.

Myeloid-derived suppressor cells promote allograft survival by suppressing regulatory T cell dysfunction in high-risk corneal transplantation.

Highly inflamed and neovascularized corneal graft beds are known as high-risk (HR) environments for transplant survival. One of the primary factors leading to this rejection is reduction in the suppressive function of regulatory T cells (Treg). Our results show that myeloid-derived suppressor cells (MDSC) counteract interleukin-6-mediated Treg dysfunction by expressing interleukin-10. Additionally, MDSC maintain forkhead box P3 stability and their ability to suppress IFN-γ+ Th1 cells. Administering MDSC to HR corneal transplant recipients demonstrates prolonged graft survival via promotion of Treg while concurrently suppressing IFN-γ+ Th1 cells. Moreover, MDSC-mediated donor-specific immune tolerance leads to long-term corneal graft survival as evidenced by the higher survival rate or delayed survival of a second-party C57BL/7 (B6) graft compared to those of third-party C3H grafts observed in contralateral low-risk or HR corneal transplantation of BALB/c recipient mice, respectively. Our study provides compelling preliminary evidence demonstrating the effectiveness of MDSC in preventing Treg dysfunction, significantly improving graft survival in HR corneal transplantation, and showing promising potential for immune tolerance induction.

Long-lived autoreactive memory CD4+ T cells mediate the sustained retinopathy in chronic autoimmune uveitis.

Chronic uveitis comprises heterogeneous clinical entities characterized by sustained and recurrent intraocular inflammation that is believed to be driven by autoimmune responses. The management of chronic uveitis is challenging with the limited availability of efficacious treatments, and the underlying mechanisms mediating disease chronicity remain poorly understood as the majority of experimental data are derived from the acute phase of the disease (the first 2-3 weeks post-induction). Herein, we investigated the key cellular mechanisms underlying chronic intraocular inflammation using our recently established murine model of chronic autoimmune uveitis. We demonstrate unique long-lived CD44hi IL-7R+ IL-15R+ CD4+ memory T cells in both retina and secondary lymphoid organs after 3 months postinduction of autoimmune uveitis. These memory T cells functionally exhibit antigen-specific proliferation and activation in response to retinal peptide stimulation in vitro. Critically, these effector-memory T cells are capable of effectively trafficking to the retina and accumulating in the local tissues secreting both IL-17 and IFN-γ upon adoptively transferred, leading to retinal structural and functional damage. Thus, our data reveal the critical uveitogenic functions of memory CD4+ T cells in sustaining chronic intraocular inflammation, suggesting that memory T cells can be a novel and promising therapeutic target for treating chronic uveitis in future translational studies.

Developing deprotectase biocatalysts for synthesis.

Organic synthesis often requires multiple steps where a functional group (FG) is concealed from reaction by a protecting group (PG). Common PGs include N-carbobenzyloxy (Cbz or Z) of amines and tert-butyloxycarbonyl (OtBu) of acids. An essential step is the removal of the PG, but this often requires excess reagents, extensive time and can have low % yield. An overarching goal of biocatalysis is to use "green" or "enzymatic" methods to catalyse chemical transformations. One under-utilised approach is the use of "deprotectase" biocatalysts to selectively remove PGs from various organic substrates. The advantage of this methodology is the exquisite selectivity of the biocatalyst to only act on its target, leaving other FGs and PGs untouched. A number of deprotectase biocatalysts have been reported but they are not commonly used in mainstream synthetic routes. This study describes the construction of a cascade to deprotect doubly-protected amino acids. The well known Bacillus BS2 esterase was used to remove the OtBu PG from various amino acid substrates. The more obscure Sphingomonas Cbz-ase (amidohydrolase) was screened with a range of N-Cbz-modified amino acid substrates. We then combined both the BS2 and Cbz-ase together for a 1 pot, 2 step deprotection of the model substrate CBz-L-Phe OtBu to produce the free L-Phe. We also provide some insight into the residues involved in substrate recognition and catalysis using docked ligands in the crystal structure of BS2. Similarly, a structural model of the Cbz-ase identifies a potential di-metal binding site and reveals conserved active site residues. This new biocatalytic cascade should be further explored for its application in chemical synthesis.

Long-term stability of gingival margin and periodontal soft-tissue phenotype achieved after mucogingival therapy: A systematic review.

BACKGROUND: The aim of this systematic review was two-fold: (i) to evaluate the long-term (≥5 years) stability of the gingival margin position, keratinized tissue width (KTW) and gingival thickness (GT) in sites that underwent root coverage (RC) or gingival augmentation (GA); and (ii) to assess the influence of different local variables on the long-term stability of dental and gingival tissues. MATERIALS AND METHODS: Randomized controlled trials (RCTs) and non-RCTs reporting short-term (i.e., 6-12 months after baseline surgical intervention) and long-term (≥5 years) follow-up data after surgical treatment of adult patients presenting single or multiple mucogingival deformities, defined as sites presenting gingival recession defects (GRDs) and/or (KTW) deficiency (i.e., <2 mm), were considered eligible for inclusion. MEDLINE-PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases were searched for articles published up to 15 May 2023. Mixed-effects multiple linear regression was used to assess the association between KTW, type of surgical procedure and time (i.e., independent variables) on the stability of the gingival margin in sites that received RC or GA therapy. RESULTS: Of the 2569 potentially eligible records, 41 (reporting 40 studies) met the eligibility criteria. Graphical estimates including data from all RC procedures found an upward trend in recession depth (RD) increase over time. Conversely, it was observed that in 63.63% of RC studies and in 59.32% of RC treatment arms KTW increased over time, particularly in sites treated with subepithelial connective tissue grafts (SCTGs). Conversely, sites that underwent GA procedures generally exhibited an overall reduction of KTW over time. However, sites treated with free gingival grafts (FGGs) showed a decrease in RD after 10 years of follow-up. Three main findings derived from the pooled estimates were identified: (i) Gingival margin stability was associated with the amount of KTW present during short-term assessment (i.e. the greater the KTW at 6-12 months after treatment, the more stable the gingival margin). (ii) The use of autogenous soft-tissue grafts was associated with lower RD increase over time. (iii) Treatment approaches that contribute to the three-dimensional enhancement of the gingival phenotype, as clearly demonstrated by FGG, were associated with gingival margin stability. CONCLUSIONS: The extent of apical migration of the gingival margin appears to be directly related to the amount of KTW and GT upon tissue maturation. Interventions involving the use of autogenous grafts, either SCTG or FGG, are associated with greater short-term KTW gain and lower RD increase over time.

The impact of donor diabetes on corneal transplant immunity.

Corneal transplantation is the most common form of solid tissue grafting, with an approximately 80% to 90% success rate. However, success rates may decline when donor tissues are derived from patients with a history of diabetes mellitus (DM). To evaluate the underlying immunopathologic processes that cause graft rejection, we used streptozotocin-induced type 1 DM (DM1) and transgenic Lepob/ob type 2 DM (DM2) diabetic murine models as donors and nondiabetic BALB/c as recipients. DM resulted in an increased frequency of corneal antigen-presenting cells (APCs) with an acquired immunostimulatory phenotype. Following transplantation, recipients that received either type of diabetic graft showed increased APC migration and T helper type 1 alloreactive cells, impaired functional regulatory T cells, and graft survival. Insulin treatment in streptozotocin-induced diabetic mice led to an increased tolerogenic profile of graft APC, lower T helper type 1 sensitization, and a higher frequency of functional regulatory T cells with high suppressive capacity, reflected in increased graft survival. We conclude that both DM1 and DM2 in donors can impact corneal APC functional phenotype, rendering the tissue more immunogenic and thereby increasing the risk of graft failure.

The Neuropeptide Alpha-Melanocyte-Stimulating Hormone Is Critical for Corneal Endothelial Cell Protection and Graft Survival after Transplantation.

Corneal transplantation is the most common form of tissue transplantation. The success of corneal transplantation mainly relies on the integrity of corneal endothelial cells (CEnCs), which maintain tissue transparency by pumping out excess water from the cornea. After transplantation, the rate of CEnC loss far exceeds that seen with normal aging, which can threaten sight. The underlying mechanisms are poorly understood. Alpha-melanocyte-stimulating hormone (α-MSH) is a neuropeptide that is constitutively found in the aqueous humor with both cytoprotective and immunomodulatory effects. The curent study found high expression of melanocortin 1 receptor (MC1R), the receptor for α-MSH, on CEnCs. The effect of α-MSH/MC1R signaling on endothelial function and allograft survival in vitro and in vivo was investigated using MC1R signaling-deficient mice (Mc1re/e mice with a nonfunctional MC1R). Herein, the results indicate that in addition to its well-known immunomodulatory effect, α-MSH has cytoprotective effects on CEnCs after corneal transplantation, and the loss of MC1R signaling significantly decreases long-term graft survival in vivo. In conclusion, α-MSH/MC1R signaling is critical for CEnC function and graft survival after corneal transplantation.

Errors and complications in clinical periodontal practice due to methodologic bias and bad interpretation of the evidence.

Different types of errors and complications may arise during and after the execution of periodontal or implant-related procedures. Some of the most relevant, although also controversial, and less commented, causative agents of errors and complications are methodological biases and bad interpretation of the evidence. Proper assessment of the literature requires of solid clinical knowledge combined with a systematic approach built on the recognition of common methodological biases and the avoidance of interpretive errors to critically retrieve, dissect, and judiciously apply available information for the promotion of periodontal and peri-implant health. This review addresses common types of methodological bias and interpretive errors that can alter the reader's perceptions on the real effect and potential ramifications of the reported outcomes of a given therapeutic approach due to bad interpretation of the available evidence: (1) types of methodological biases; (2) spin and interpretive bias; (3) interpretation pitfalls when assessing the evidence (4) choice of relevant endpoints to answer the question(s) of interest; and (5) balance between statistical significance and clinical relevance.

Treatment alternatives for the rehabilitation of the posterior edentulous maxilla.

Rehabilitation of the edentulous maxilla with implant-supported fixed dental prostheses can represent a significant clinical challenge due to limited bone availability and surgical access, among other factors. This review addresses several treatment options to replace missing teeth in posterior maxillary segments, namely the placement of standard implants in conjunction with maxillary sinus floor augmentation, short implants, tilted implants, and distal cantilever extensions. Pertinent technical information and a concise summary of relevant evidence on the reported outcomes of these different therapeutic approaches are presented, along with a set of clinical guidelines to facilitate decision-making processes and optimize the outcomes of therapy.

Alveolar ridge preservation: Complications and cost-effectiveness.

Alveolar ridge preservation is routinely indicated in clinical practice with the purpose of attenuating postextraction ridge atrophy. Over the past two decades numerous clinical studies and reviews on this topic have populated the literature. In recent years the focus has primarily been on analyzing efficacy outcomes pertaining to postextraction dimensional changes, whereas other relevant facets of alveolar ridge preservation therapy have remained unexplored. With this premise, we carried out a comprehensive evidence-based assessment of the complications associated with different modalities of alveolar ridge preservation and modeled the cost-effectiveness of different therapeutic modalities as a function of changes in ridge width and height. We conclude that, among allogeneic and xenogeneic bone graft materials, increased expenditure does not translate into increased effectiveness of alveolar ridge preservation therapy. On the other hand, a significant association between expenditure on a barrier membrane and reduced horizontal and vertical ridge resorption was observed, though only to a certain degree, beyond which the return on investment was significantly diminished.

Outcome measures and methods of assessment of soft tissue augmentation interventions in the context of dental implant therapy: A systematic review of clinical studies published in the last 10 years.

AIM: To identify and report outcome measures and methods of assessment on soft tissue augmentation interventions in the context of dental implant therapy reported in clinical studies published in the last 10 years. MATERIALS AND METHODS: The protocol of this Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) 2020-compliant systematic review was registered in PROSPERO (CRD42021252214). A literature search was conducted to identify articles that met the pre-established eligibility criteria. Data of interest, with an emphasis on outcome measures, were extracted. For each outcome, specific methods and timing of assessment were described in detail. Following a critical qualitative analysis of the data, outcome measures were categorized. Primary outcomes were identified, and the frequency of reporting in the selected articles was calculated. Additionally, risk-of-bias assessments were performed for individual articles and primary outcomes. RESULTS: Ninety-two articles, of which 39 reported randomized controlled trials (RCTs), 20 non-RCTs, and 33 case series studies, were selected. Outcome measures were categorized into either investigator-evaluated outcome measures (i.e., clinical, digital imaging, aesthetic, histological, biomarker, and safety) or patient-reported outcome measures (PROMs). Clinical outcomes were the most frequently reported type of outcome. Considering all categories, the most frequently reported primary outcomes were facial mucosa thickness assessed with clinical methods (22.83%), facial keratinized mucosa width assessed with clinical methods (19.57%), facial mucosal margin position/recession assessed with clinical methods (18.48%), facial mucosa thickness assessed with digital imaging methods (11.96%), facial soft tissue volume assessed with digital imaging methods (9.78%), and supracrestal tissue height assessed with clinical methods (9.78%). No distinguishable patterns of association between specific types or quality (level of bias) of clinical studies and the choice of primary outcomes were observed. CONCLUSIONS: Clinical research on peri-implant soft tissue augmentation has progressively increased in the last 10 years. Although clinical outcome measures were the most frequently reported outcomes in the selected literature, trends in the field are indicative of a shift from traditional clinical assessment methods to the use of digital technologies. PROMs were generally under-reported but should be considered an integral methodological component in future clinical studies.

Effect of periodontal phenotype characteristics on post-extraction dimensional changes of the alveolar ridge: A prospective case series.

AIM: This study was primarily aimed at assessing the effect that specific periodontal phenotypical characteristics have on alveolar ridge remodelling after tooth extraction. MATERIALS AND METHODS: Patients in need of extraction of a non-molar maxillary tooth were enrolled. Baseline phenotypical characteristics (i.e., mid-facial and mid-palatal soft tissue and bone thickness, and supracrestal soft tissue height [STH]) were recorded upon extraction. A set of clinical, digital imaging (linear and volumetric), and patient-reported outcomes were assessed over a 14-week healing period. RESULTS: A total of 78 subjects were screened. Forty-two subjects completed the study. Linear and volumetric bone changes, as well as vertical linear soft tissue and alveolar ridge volume (soft tissue contour) variations, were indicative of a marked dimensional reduction of the alveolar ridge over time. Horizontal facial and palatal soft tissue thickness gain was observed. Thin facial bone (≤1 mm) upon extraction, compared with thick facial bone (>1 mm), was associated with greater linear horizontal (-4.57 ± 2.31 mm vs. -2.17 ± 1.65 mm, p = .003) and vertical mid-facial (-0.95 ± 0.67 mm vs. -4.08 ± 3.52 mm, p < 0.001) and mid-palatal (-2.03 ± 2.08 mm vs. -1.12 ± 0.99 mm, p = 0.027) bone loss, as well as greater total (-34% ± 10% vs. 15% ± 6%, p < 0.001), facial (-51% ± 19% vs. 28% ± 18%, p = 0.040), and palatal bone volume reduction (-26% ± 14% vs. -8% ± 10%, p < 0.001). Aside from alveolar bone thickness, STH was also found to be a predictor of alveolar ridge resorption since this variable was directly correlated with bone volume reduction. Patient-reported discomfort scores progressively decreased over time, and the mean satisfaction upon study completion was 94.5 ± 0.83 out of 100. CONCLUSIONS: Alveolar ridge remodelling is a physiological phenomenon that occurs after tooth extraction. Post-extraction alveolar ridge atrophy is more marked on the facio-coronal aspect. These dimensional changes are more pronounced in sites exhibiting a thin facial bone phenotype (Clinicaltrials.gov NCT02668289).

Histological assessment and gene expression analysis of intra-oral soft tissue graft donor sites.

AIM: To determine the structural and gene expression features of different intra-oral soft tissue donor sites (i.e., anterior palate, posterior palate, maxillary tuberosity and retromolar pad). MATERIALS AND METHODS: Standardized mucosal tissue punch biopsies were collected from at least one donor site per subject. Histological processing was performed to determine tissue morphometry and quantify collagen composition. Site-specific gene distribution was mapped using targeted gene expression analysis and validated using real time polymerase chain reaction (qPCR). RESULTS: A total of 50 samples from 37 subjects were harvested. Epithelial thickness did not differ between sites. However, lamina propria was thicker in the maxillary tuberosity (2.55 ± 0.92 mm) and retromolar pad (1.98 ± 0.71 mm) than in the lateral palate. Type I collagen was the predominant structural protein in the lamina propria (75.06%-80.21%). Genes involving collagen maturation and extracellular matrix regulation were highly expressed in the maxillary tuberosity and retromolar pad, while lipogenesis-associated genes were markedly expressed in the lateral palate. The retromolar pad showed the most distinct gene expression profile, and the anterior and posterior palate displayed similar transcription profiles. CONCLUSIONS: Tissue samples harvested from the anterior and posterior palate differed morphologically from those from the maxillary tuberosity and retromolar pad. Each intra-oral site showed a unique gene expression profile, which might impact their biological behaviour and outcomes of soft tissue augmentation procedures.

Influence of healing time on the outcomes of alveolar ridge preservation using a collagenated bovine bone xenograft: A randomized clinical trial.

AIM: To evaluate the healing outcomes in non-molar post-extraction sockets filled with deproteinized bovine bone mineral with collagen (DBBM-C) as a function of time. MATERIALS AND METHODS: Patients in need of non-molar tooth extraction were randomly allocated into one of three groups according to the total healing time (A-3 months; B-6 months; C-9 months). The effect of alveolar ridge preservation (ARP) therapy via socket filling using DBBM-C and socket sealing with a porcine collagen matrix (CM) was assessed based on a panel of clinical, digital, histomorphometric, implant-related, and patient-reported outcomes. RESULTS: A total of 42 patients completed the study (n = 14 in each group). Histomorphometric analysis of bone core biopsies obtained at the time of implant placement showed a continuous increase in the proportion of mineralized tissue with respect to non-mineralized tissue, and a decrease in the proportion of remaining xenograft material over time. All volumetric bone and soft tissue contour assessments revealed a dimensional reduction of the alveolar ridge overtime affecting mainly the facial aspect. Linear regression analyses indicated that baseline buccal bone thickness is a strong predictor of bone and soft tissue modelling. Ancillary bone augmentation at the time of implant placement was needed in 16.7% of the sites (A:2; B:1; C:4). Patient-reported discomfort and wound healing index scores progressively decreased over time and was similar across groups. CONCLUSIONS: Healing time influences the proportion of tissue compartments in non-molar post-extraction sites filled with DBBM-C and sealed with a CM. A variable degree of alveolar ridge atrophy, affecting mainly the facial aspect, occurs even after performing ARP therapy. These changes are more pronounced in sites exhibiting thin facial bone (≤1 mm) at baseline (Clinicaltrials.gov NCT03659617).

Relevant domains, core outcome sets and measurements for implant dentistry clinical trials: The Implant Dentistry Core Outcome Set and Measurement (ID-COSM) international consensus report.

AIM: Lack of consistently reported outcomes limits progress in evidence-based implant dentistry and quality of care. The objective of this initiative was to develop a core outcome set (COS) and measurements for implant dentistry clinical trials (ID-COSM). MATERIALS AND METHODS: This Core Outcome Measures in Effectiveness Trials (COMET)-registered international initiative comprised six steps over 24 months: (i) systematic reviews of outcomes reported in the last 10 years; (ii) international patient focus groups; (iii) a Delphi project with a broad range of stakeholders (care providers, clinical researchers, methodologists, patients and industry representatives); (iv) expert group discussions organizing the outcomes in domains using a theoretical framework and identifying the COSs; (v) identification of valid measurement systems to capture the different domains and (vi) final consensus and formal approval involving experts and patients. The methods were modified from the best practice approach following the Outcome Measures in Rheumatoid Arthritis Clinical Trial and COMET manuals. RESULTS: The systematic reviews and patient focus groups identified 754 (665 + 89, respectively) relevant outcome measures. After elimination of redundancies and duplicates, 111 were formally assessed in the Delphi project. By applying pre-specified filters, the Delphi process identified 22 essential outcomes. These were reduced to 13 after aggregating alternative assessments of the same features. The expert committee organized them into four core outcome areas: (i) pathophysiology, (ii) implant/prosthesis lifespan, (iii) life impact and (iv) access to care. In each area, core outcomes were identified to capture both the benefits and harms of therapy. Mandatory outcome domains included assessment of surgical morbidity and complications, peri-implant tissue health status, intervention-related adverse events, complication-free survival and overall patient satisfaction and comfort. Outcomes deemed mandatory in specific circumstances comprised function (mastication, speech, aesthetics and denture retention), quality of life, effort for treatment and maintenance and cost effectiveness. Specialized COSs were identified for bone and soft-tissue augmentation procedures. The validity of measurement instruments ranged from international consensus (peri-implant tissue health status) to early identification of important outcomes (patient-reported outcomes identified by the focus groups). CONCLUSIONS: The ID-COSM initiative reached a consensus on a core set of mandatory outcomes for clinical trials in implant dentistry and/or soft tissue/bone augmentation. Adoption in future protocols and reporting on the respective domain areas by currently ongoing trials will contribute to improving evidence-informed implant dentistry and quality of care.

Outcome measures and methods of assessment of soft-tissue augmentation interventions in the context of dental implant therapy: A systematic review of clinical studies published in the last 10 years.

AIM: The aim of the study was to identify and report outcome measures and methods of assessment on soft-tissue augmentation interventions in the context of dental implant therapy reported in clinical studies published in the last 10 years. MATERIAL AND METHODS: The protocol of this PRISMA 2020-compliant systematic review was registered in PROSPERO (CRD42021252214). A literature search was conducted to identify articles that met the pre-established eligibility criteria. Data of interest, with an emphasis on outcome measures, were extracted. For each outcome, specific methods and timing of assessment were described in detail. Following a critical qualitative analysis of the data, outcome measures were categorized. Primary outcomes were identified and the frequency of reporting in the selected articles was calculated. Additionally, risk of bias assessments were performed for individual articles and primary outcomes. RESULTS: Ninety-two articles, of which 39 reported randomized controlled trials (RCTs), 20 reported non-RCTs, and 33 reported case series studies, were selected. Outcome measures were categorized into either investigator-evaluated outcome measures (i.e., clinical, digital imaging, esthetic, histologic, biomarker, and safety) or patient-reported outcome measures (PROMs). Clinical outcomes were the most frequently reported type of outcome. Considering all categories, the most frequently reported primary outcomes were facial mucosa thickness assessed with clinical methods (22.83%), facial keratinized mucosa width assessed with clinical methods (19.57%), facial mucosal margin position/recession assessed with clinical methods (18.48%), facial mucosa thickness assessed with digital imaging methods (11.96%), facial soft-tissue volume assessed with digital imaging methods (9.78%), and supracrestal tissue height assessed with clinical methods (9.78%). No distinguishable patterns of association between specific types or quality (level of bias) of clinical studies and the choice of primary outcomes were observed. CONCLUSION: Clinical research on peri-implant soft-tissue augmentation has progressively increased in the last 10 years. Although clinical outcome measures were the most frequently reported outcomes in the selected literature, trends in the field are indicative of a shift from traditional clinical assessment methods to the use of digital technologies. PROMs were generally underreported but should be considered an integral methodological component in future clinical studies.

Relevant domains, core outcome sets and measurements for implant dentistry clinical trials: The Implant Dentistry Core Outcome Set and Measurement (ID-COSM) international consensus report.

AIM: Lack of consistently reported outcomes limits progress in evidence-based implant dentistry and quality of care. The objective of this initiative was to develop a core outcome set (COS) and measurements for implant dentistry clinical trials (ID-COSM). MATERIALS AND METHODS: This Core Outcome Measures in Effectiveness Trials (COMET)-registered international initiative comprised six steps over 24 months: (i) systematic reviews of outcomes reported in the last 10 years; (ii) international patient focus groups; (iii) a Delphi project with a broad range of stakeholders (care providers, clinical researchers, methodologists, patients and industry representatives); (iv) expert group discussions organizing the outcomes in domains using a theoretical framework and identifying the COSs; (v) identification of valid measurement systems to capture the different domains and (vi) final consensus and formal approval involving experts and patients. The methods were modified from the best practice approach following the Outcome Measures in Rheumatoid Arthritis Clinical Trial and COMET manuals. RESULTS: The systematic reviews and patient focus groups identified 754 (665 + 89, respectively) relevant outcome measures. After elimination of redundancies and duplicates, 111 were formally assessed in the Delphi project. By applying pre-specified filters, the Delphi process identified 22 essential outcomes. These were reduced to 13 after aggregating alternative assessments of the same features. The expert committee organized them into four core outcome areas: (i) pathophysiology, (ii) implant/prosthesis lifespan, (iii) life impact and (iv) access to care. In each area, core outcomes were identified to capture both the benefits and harms of therapy. Mandatory outcome domains included assessment of surgical morbidity and complications, peri-implant tissue health status, intervention-related adverse events, complication-free survival and overall patient satisfaction and comfort. Outcomes deemed mandatory in specific circumstances comprised function (mastication, speech, aesthetics and denture retention), quality of life, effort for treatment and maintenance and cost effectiveness. Specialized COSs were identified for bone and soft-tissue augmentation procedures. The validity of measurement instruments ranged from international consensus (peri-implant tissue health status) to early identification of important outcomes (patient-reported outcomes identified by the focus groups). CONCLUSIONS: The ID-COSM initiative reached a consensus on a core set of mandatory outcomes for clinical trials in implant dentistry and/or soft tissue/bone augmentation. Adoption in future protocols and reporting on the respective domain areas by currently ongoing trials will contribute to improving evidence-informed implant dentistry and quality of care.

Impact of peri-implant soft tissue characteristics on health and esthetics.

OBJECTIVE: To review the impact of key peri-implant soft tissue characteristics on health and esthetics. MAIN CONSIDERATIONS: The keratinized mucosa width (KMW), the mucosal thickness (MT), and the supracrestal tissue height (STH) are essential components of the peri-implant soft tissue phenotype. An inadequate KMW (<2 mm) has been associated with local discomfort upon oral hygiene performance and increased risk for the onset of peri-implant diseases. A minimum buccal MT (≥2 mm) is generally required to prevent esthetic issues related to the effect of transmucosal prosthetic elements on the color of the mucosa and can also contribute to long-term mucosal stability. STH is directly related to marginal bone remodeling patterns during the early healing process that follows the connection of transmucosal prosthetic components. Short STH, generally defined as <3 mm, has been consistently associated with marginal bone loss resulting from the physiologic establishment of the mucosal seal. Insufficient STH may also derive into the fabrication of unfavorable transmucosal prosthetic contours, which frequently results in unpleasing esthetic outcomes and predisposes to submarginal biofilm accumulation. Peri-implant soft tissue dehiscences (PISTDs) are a type of peri-implant deformity that are associated with esthetic issues and often occur in sites presenting KMW, MT, and/or STH deficiencies. PISTDs should be correctly diagnosed and treated accordingly, usually by means of multidisciplinary therapy. CONCLUSION: Understanding the impact of different dimensional and morphologic features of the peri-implant mucosa on health and esthetic outcomes is fundamental to make appropriate clinical decisions in the context of tooth replacement therapy with implant-supported prostheses.

BioWF: A Naturally-Fused, Di-Domain Biocatalyst from Biotin Biosynthesis Displays an Unexpectedly Broad Substrate Scope.

The carbon backbone of biotin is constructed from the C7 di-acid pimelate, which is converted to an acyl-CoA thioester by an ATP-dependent, pimeloyl-CoA synthetase (PCAS, encoded by BioW). The acyl-thioester is condensed with ʟ-alanine in a decarboxylative, Claisen-like reaction to form an aminoketone (8-amino-7-oxononanoic acid, AON). This step is catalysed by the pyridoxal 5'-phosphate (PLP)-dependent enzyme (AON synthase, AONS, encoded by BioF). Distinct versions of Bacillus subtilis BioW (BsBioW) and E. coli BioF (EcBioF) display strict substrate specificity. In contrast, a BioW-BioF fusion from Corynebacterium amycolatum (CaBioWF) accepts a wider range of mono- and di-fatty acids. Analysis of the active site of the BsBioW : pimeloyl-adenylate complex suggested a key role for a Phe (F192) residue in the CaBioW domain; a F192Y mutant restored the substrate specificity to pimelate. This surprising substrate flexibility also extends to the CaBioF domain, which accepts ʟ-alanine, ʟ-serine and glycine. Structural models of the CaBioWF fusion provide insight into how both domains interact with each other and suggest the presence of an intra-domain tunnel. The CaBioWF fusion catalyses conversion of various fatty acids and amino acids to a range of AON derivatives. Such unexpected, natural broad substrate scope suggests that the CaBioWF fusion is a versatile biocatalyst that can be used to prepare a number of aminoketone analogues.