Short (≤6 mm) compared with ≥10-mm dental implants in different clinical scenarios: A systematic review of randomized clinical trials with meta-analysis, trial sequential analysis and quality of evidence grading.

AIM: To systematically identify, synthesize and critically summarize the available scientific evidence from randomized controlled trials (RCTs) regarding whether short (≤6 mm) perform as well as long (≥10 mm) implants regarding implant survival, marginal bone loss, and biologic and prosthetic complications in different clinical scenarios. MATERIALS AND METHODS: Cochrane Collaboration's risk of bias tool and the GRADE approach were applied. Results were synthesized using random-effects meta-analyses assessed by trial sequential analyses. RESULTS: Forty reports on 19 RCTs comprising 2214 (1097 short; 1117 long) implants were included. Moderate/high certainty/quality evidence demonstrated similar 5-year survival rates for ≤6-mm and ≥10-mm implants in non-augmented bone and full-mouth rehabilitation in either jaw, and for 6-mm implants in the maxilla instead of sinus lift. Nevertheless, the evidence for 5-year survival rates remains inconclusive or insufficient for the remaining combinations of implant lengths and clinical scenarios. They include 4-mm and 5-mm implants as alternatives to sinus lift as well as placing all implant lengths ≤6 mm instead of vertical ridge augmentation with long implants. Marginal bone level and short- and long-term biologic or prosthetic complications were similar. CONCLUSIONS: Based on moderate/high certainty/quality evidence from 5-year RCTs, implants ≤6 mm may be viable alternatives to ≥10-mm implants in either jaw in native bone and full-arch rehabilitation, and 6-mm implants may be used as an alternative to sinus lift. TRIAL REGISTRATION: PROSPERO ID: CRD42021254365.

Insights and Advancements in Periodontal Tissue Engineering and Bone Regeneration.

The regeneration of periodontal bone defects continues to be an essential therapeutic concern in dental biomaterials. Numerous biomaterials have been utilized in this sector so far. However, the immune response and vascularity in defect regions may be disregarded when evaluating the effectiveness of biomaterials for bone repair. Among several regenerative treatments, the most recent technique of in situ tissue engineering stands out for its ability to replicate endogenous restorative processes by combining scaffold with particular growth factors. Regenerative medicine solutions that combine biomaterials/scaffolds, cells, and bioactive substances have attracted significant interest, particularly for bone repair and regeneration. Dental stem cells (DSCs) share the same progenitor and immunomodulatory properties as other types of MSCs, and because they are easily isolable, they are regarded as desirable therapeutic agents in regenerative dentistry. Recent research has demonstrated that DSCs sown on newly designed synthetic bio-material scaffolds preserve their proliferative capacity while exhibiting increased differentiation and immuno-suppressive capabilities. As researchers discovered how short peptide sequences modify the adhesion and proliferative capacities of scaffolds by activating or inhibiting conventional osteogenic pathways, the scaffolds became more effective at priming MSCs. In this review, the many components of tissue engineering applied to bone engineering will be examined, and the impact of biomaterials on periodontal regeneration and bone cellular biology/molecular genetics will be addressed and updated.

6 mm short versus 11 mm long inter-foraminal implants in the full-arch rehabilitation of edentulous non-atrophic mandibles: 5-year results from a multicenter randomized controlled trial.

OBJECTIVE: The aim of this multicenter parallel-group randomized controlled trial is to compare, in the same clinical scenario, 6 mm short with 11 mm long implants for the rehabilitation of completely edentulous non-atrophic mandibles. MATERIALS AND METHODS: Thirty patients in three study centers received a fixed full-arch mandibular rehabilitation supported by five inter-foraminal implants, with no need for bone augmentation procedures. Patients were randomly allocated (1:1 ratio), at the time of surgery, to test (6 mm implants) or control group (11 mm implants). After 3 months, a screw-retained full-arch prosthesis was positioned (baseline). Peri-implant marginal bone level change (MBLc, primary outcome) together with implant and prosthesis survival rate, and biological/technical complications (secondary outcomes) were evaluated up to 5 years. RESULTS: Twenty seven patients were controlled at 5 years (3 drop-outs). No implant or prosthesis loss occurred. No significant intergroup difference for biological/technical complications (p > .05, Fisher's exact test) and no significant intragroup and intergroup difference in the MBLc values were registered (test -0.03 ± 0.17 mm and control -0.13 ± 0.32 mm at 5-years; p > .025, one-sided Mann-Whitney U-test). CONCLUSIONS: When used in comparable anatomic, surgical, and prosthetic conditions, no difference in the clinical and radiographic outcomes between 6-mm and 11-mm implants was observed at 5 years of follow-up. Short implants showed to be a reliable option for the rehabilitation of completely edentulous non-atrophic mandibles. There is growing clinical evidence supporting the use of short implants, even in the case of non-atrophic sites.

Clinical and microbiological efficacy of indocyanine green-based antimicrobial photodynamic therapy as an adjunct to non-surgical treatment of periodontitis: a randomized controlled clinical trial.

OBJECTIVES: The aim of the present randomized clinical trial (RCT) with a parallel arm design was to evaluate the clinical and microbiological efficacy of repeated ICG-aPDT as an adjunct to full-mouth subgingival debridement in the treatment of periodontitis. MATERIALS AND METHODS: Twenty-four periodontitis patients were treated with full-mouth ultrasonic subgingival debridement (FMUD). Initial sites with probing depth (PD) > 4 mm were randomly assigned to receive the test (ICG-aPDT with an 810 nm diode laser) or the control treatment (off-mode aPDT) one and four weeks after FMUD. Clinical parameters were registered after 3 and 6 months. The presence of the main periodontal pathogens in subgingival samples was assessed with real-time PCR. RESULTS: Both treatment modalities resulted in significant clinical improvements at 3 and 6 months. The only significant differences in favour of the test group were found at 6 months for a higher PD reduction in initial deep pockets (PD ≥ 6 mm) and a higher percentage of closed pockets (PD ≤ 4 mm/no bleeding on probing). Limited microbiological changes were observed in both groups after treatment with no inter-group difference, except for a more significant reduction in Aggregatibacter actinomycetemcomitans and Parvimonas micra levels in the test group at 3 months. CONCLUSION: The combination of repeated ICG-aPDT and FMUD provided no benefits except for selective clinical and microbiological improvements compared to FMUD alone. CLINICAL RELEVANCE: Based on the obtained results, only limited adjunctive effects could be found for the combined use of ICG-aPDT and FMUD. Further, well-designed RCT with larger sample sizes are required to confirm these findings. TRIAL REGISTRATION: ClinicalTrials.gov NCT04671394.

Pre-treatment neutrophil-to-lymphocyte ratio is an independent prognostic factor in head and neck squamous cell carcinoma: Meta-analysis and trial sequential analysis.

Inflammation seems to play a critical role in the development and progression of different cancers. Neutrophil-to-lymphocyte ratio (NLR) is an easily measurable marker of systemic inflammation. The purpose of this systematic review and meta-analysis was to evaluate the prognostic role of the pre-treatment NLR, in terms of overall survival (OS) and disease-free survival (DFS), in patients with primary head and neck squamous cell carcinoma (HNSCC) treated by surgery alone or followed by chemo/radiotherapy. This systematic review was performed according to the guidelines reported in the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Meta-analysis of OS and DFS was performed using the inverse of variance test. Fixed-effect models were used on the basis of the presence of heterogeneity. Risk of bias assessment and trial sequential analysis (TSA) were also performed; the quality of the evidence was evaluated via the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. The analysis revealed that a higher value of pre-treatment NLR correlates with a statistically significant decrease of OS (HR, 1.56; 95% CI: [1.35, 1.80]; p < 0.00001) and a lower DFS (HR, 1.64; 95% CI: [1.30, 2.07]; p < 0.0001) in HNSCC patients.

Influence of abutment material and modifications on peri-implant soft-tissue attachment: A systematic review and meta-analysis of histological animal studies.

STATEMENT OF PROBLEM: How the properties of the implant-abutment unit may affect the peri-implant soft-tissue seal, whose stability is considered key to safeguarding the implant from bacterial contamination and preserve peri-implant health conditions, is unclear. PURPOSE: The purpose of this systematic review and meta-analysis of animal studies was to investigate whether material and surface properties of transmucosal implant components can influence the peri-implant soft-tissue adhesion at a histological level. MATERIAL AND METHODS: An electronic and hand search was conducted until August 2019. Histological animal studies comparing soft-tissue response to abutment or transmucosal collar with different materials and/or surface characteristics were selected by 2 independent reviewers. Risk of bias in individual studies was evaluated. Histomorphometric data on the dimension of the peri-implant attachment were recorded, and a quantitative synthesis by a meta-analysis was performed. Risk of bias in individual studies was evaluated in accordance with the Systematic Review Centre for Laboratory Animal Experimentation Risk of Bias tool. RESULTS: Eighteen relevant studies out of 1187 were identified, none with a low risk of bias for all domains. Data from only 4 studies could be meta-analyzed. Comparable results in terms of peri-implant attachment dimensions between test and control groups were found, except for a significantly higher apical junctional epithelium to coronal bone to implant (ajE-CBI) distance for chemically modified acid-etched compared with titanium machined surfaces. Non-meta-analyzable and/or qualitative results highlighted some improved properties also for microgrooved and oxidized surfaces. CONCLUSIONS: Limited data from animal studies suggest that some characteristics of the transmucosal implant components may affect peri-implant soft-tissue adhesion and stabilization but do not allow definitive conclusions. Future research should improve study design to increase the availability of comparable and suitable data on this topic.

6-mm-short and 11-mm-long implants compared in the full-arch rehabilitation of the edentulous mandible: A 3-year multicenter randomized controlled trial.

OBJECTIVE: The aim of this multicenter parallel-group randomized controlled trial is to compare 6-mm-short with 11-mm-long implants in the rehabilitation of totally edentulous mandible in a completely comparable clinical situation, from anatomical, surgical, and prosthetic point of view. MATERIAL AND METHODS: Thirty patients were selected in three study centers to receive a fixed full-arch mandibular rehabilitation supported by five inter-foraminal implants. Patients were randomly allocated, at the time of surgery, half to the test group (6-mm-long implants) and half to the control group (11-mm-long implants). No bone augmentation procedure was performed. After 3 months, a screw-retained full-arch prosthesis with distal cantilevers was positioned (baseline). Peri-implant marginal bone level change (MBLc), implant and prosthesis survival rate, and biological/technical complications were evaluated after 1 and 3 years. RESULTS: Thirty subjects (150 implants) were evaluated after 1 year and 28 (140 implants) after 3 years. No implant or prosthesis loss occurred. No significant inter-group difference for biological/technical complications was registered. No statistically significant (p > .025) intra-group or inter-group difference in the mean MBLc values was registered. The mean MBLc was 0.01 ± 0.19 mm and -0.04 ± 0.21 mm at 1 year, and -0.10 ± 0.24 mm and 0.02 ± 0.25 mm at 3 years (test and control groups, respectively). CONCLUSIONS: 6-mm-short implants may be a reliable option when used in the rehabilitation of total edentulous mandibles. These results need to be confirmed by longer follow-up data from well-designed randomized controlled clinical trials.

Periodontitis, Low-Grade Inflammation and Systemic Health: A Scoping Review.

Background and objectives: Periodontitis is a multifactorial chronic inflammatory infectious disease in which an infection is necessary, but not sufficient, for development of the condition. Individual susceptibility strictly linked to the immune and inflammatory response of the organism must also be present. Low-grade inflammation (LGI) is a systemic status of chronic sub-clinical production of inflammatory factors. This condition represents a risk factor for many chronic diseases including diabetes, cardiovascular disease, cerebrovascular disease, neurodegenerative disease and cancer. This scoping review aims to clarify, summarize and disseminate current knowledge on the possible link between periodontitis, LGI and systemic health. Materials and Methods: PRISMA Extension for Scoping Reviews guidelines were followed. An ad-hoc created keyword string was used to search the electronic databases of PubMed/Medline, Embase, The Cochrane Library and ClinicalTrials.gov. A hand search of specialized journals and their reference lists was also performed. Results: 14 studies that respected eligibility criteria were selected and analyzed. There is emerging evidence of strong links between periodontitis, LGI and systemic health. On the one hand, periodontitis influences the systemic status of LGI and on the other hand, the systemic production of inflammatory factors affects periodontitis with a bidirectional connection. Conclusions: LGI and the subsequent onset of a systemic inflammatory phenotype can be considered the common substrate of many chronic inflammatory diseases including periodontitis, with multiple mutual connections between them. Understanding of the biological principles and mechanisms underlying such a complex interrelationship could lead to significant improvements in the field of personalized diagnostics and therapeutic protocols.

The Role of Autologous Platelet Concentrates in Alveolar Socket Preservation: A Systematic Review.

Prevention of alveolar bone resorption after tooth extraction may be useful for implant rehabilitation of the edentulous site minimizing the future need for bone augmentation procedures. A number of studies have investigated the efficacy of autologous platelet concentrates for the preservation of the alveolar bone volume after tooth extraction. Although encouraging results have been published, the available data are still controversial. The aim of the present systematic review was to assess the effect of platelet concentrates on alveolar socket preservation after tooth extraction. A literature search was carried out up to September 2017 for prospective controlled trials in which a test group using exclusively a platelet concentrate was compared with a control group in which extraction sockets were left to heal spontaneously. Seven controlled clinical trials published between 2010 and 2016 were included. A total of 320 extractions (170 tests and 150 controls) in 190 patients was considered. A great heterogeneity was found in terms of study design, methodological aspects, and outcome evaluation. For this reason, a quantitative analysis followed by meta-analysis was not possible, and only a descriptive analysis on the role of platelet concentrates in alveolar socket preservation was carried out. There is growing evidence that platelet concentrates may be advantageously used in postextraction sites, mainly to improve soft tissue healing and to reduce postoperative symptoms. Data about their potential in preserving the alveolar bone volume are still scarce and controversial, although recently encouraging results have been presented using more reliable and accurate evaluation technologies, such as the computed tomography. Further, well-designed and methodologically standardized investigations are strongly demanded to reach a higher level of evidence on this topic.

The Use of Poly-d,l-lactic Acid (PDLLA) Devices for Bone Augmentation Techniques: A Systematic Review.

Poly-d,l-lactic acid (PDLLA) has been proposed in dentistry for regenerative procedures in the form of membranes, screws, and pins. The aim of this review was to evaluate the efficacy of bone augmentation techniques using PDLLA devices. A literature search was carried out by two independent and calibrated reviewers. All interventional and observational studies assessing the efficacy of bone augmentation techniques using PDLLA devices were included. Six studies were included. The relevant variability of design and methods impeded any qualitative or quantitative comparison. Ease of handling, absence of a re-entry phase, moldability of foils, and good soft-tissue response were appreciated characteristics of PDLLA devices. Some drawbacks such as the risk of membrane exposition, a prolonged adsorbability, and a tendency to a fibrous encapsulation of the PDLLA devices have been described, although the clinical significance of these findings is unclear. Clinical data about PDLLA devices for bone regeneration are very scarce and heterogenous. Well-designed randomized controlled trials comparing the use of PDLLA foils and pins with conventional membranes for bone regeneration are strongly encouraged in order to understand the real clinical benefits/drawbacks of this technique.

Bacterial inactivation/sterilization by argon plasma treatment on contaminated titanium implant surfaces: In vitro study.

BACKGROUND: Surface treatment by argon plasma is widely used as the last step of the manufacturing process of titanium implant fixtures before their sterilization by gamma rays. The possibility of using such a technology in the daily clinical practice is particularly fascinating. The aim of the present study was to assess the effects of the argon plasma treatment on different titanium implant surfaces previously exposed in vitro to bacterial contamination. MATERIAL AND METHODS: Sterile c.p. titanium implant discs with turned (T, Sa: 0.8µm), sandblasted/acid-etched (SAE, Sa: 1.3µm) and titanium plasma sprayed (TPS, Sa: 3.0µm) surface were used in this study. A strain of Aggregatibacter actinomycetemcomitans ATCC3718 was grown at 37°C under anaerobic conditions for 24 h and then transferred on six discs for each of the three surface types. After 24 hours, a half of the contaminated discs (control group) were directly used to evaluate the colony forming units (CFUs). The other half of the contaminated discs (test group) were treated in an argon plasma chamber for 12 minutes at room temperature prior to be analyzed for CFU counting. All assays were performed using triplicate samples of each material in 3 different experiments. RESULTS: When the CFU counting was carried out on control discs, a total of 1.50x106±1.4x105, 1.55x106±7.07x104 and 3.15x106±2.12x105 CFU was respectively assessed for T, SAE and TPS discs, without statistically significant differences among the three surfaces. On the contrary, any trace of bacterial contamination was assessed for titanium discs treated in the argon plasma chamber prior to be analyzed, irrespectively to the implant surface tested. CONCLUSIONS: Within the limit of this study, reported data suggested that the argon plasma technology could be efficiently used to decontaminate/sterilize previously infected titanium implant surfaces.

Poly-D-L-Lactic Acid Membranes for Bone Regeneration.

PURPOSE: To histologically and histomorphometrically evaluate the biocompatibility and the biological properties of perforated and nonperforated poly-D-L-lactic acid (PDLLA) resorbable membranes, using a model of calvarial monocortical bone defects in domestic pigs. METHODS: A total of 6 10 × 10 × 10  mm circular calvarial bone defects were prepared in each of the 3 adult female large white domestic pigs and assigned to the following experimental groups: negative control, nonperforated membrane only, perforated membrane only, bone only, bone + nonperforated membrane, and bone + perforated membrane. The PDLLA membranes were fixed by PDLLA pins by means of an ultrasonic device. After 40 days, bone blocks containing the defects were harvested and histologically processed. RESULTS: A close contact between the PDLLA devices and the surrounding bone was found, and no trace of inflammatory tissue or signs of infection were detected. Bone regeneration occurred from the preexisting bone with a centripetal pattern. Incomplete bone filling was found in empty defects, whereas all sites filled with bone showed a complete bone formation, irrespectively of the presence and the type of membrane used. CONCLUSION: PDLLA membranes and pins showed to be highly biocompatible toward bone tissue and to do not interfere with the bone healing process of monocortical calvaria defects in domestic pigs. No adjunctive effect of PDLLA membranes, irrespectively of their perforated/nonperforated structure, could be evidenced in terms of bone regeneration under the present experimental conditions. Further studies are needed to investigate the regenerative potential of such devices in other clinically relevant models.

Antibiotic-Prescribing Habits in Dentistry: A Questionnaire-Based Study.

The problem of antibiotic resistance is becoming increasingly serious worldwide due to uncontrolled prescription. Dentists are among the groups that prescribe the most antibiotics, often to delay urgent treatment. The purpose of the present study is to investigate the prescribing protocols adopted by dentists for prophylaxis and antibiotic therapy in major clinical surgical indications. METHODS: A ten-question survey was administered to a group of Italian dentists. The participants were asked about their preferences for antibiotic administration for the prevention of infective endocarditis, the administration of antibiotics to patients allergic to penicillin, the insertion of implants, and the extraction of third molars. The retrieved data were screened and analyzed. RESULTS: A total of 298 surveys were filled out. The most-prescribed antibiotic was amoxicillin or amoxicillin with clavulanic acid or macrolides for allergic patients. The administration of two grams of amoxicillin one hour before surgery was the most widely used prescriptive protocol for prophylaxis. International guidelines on antibiotic prophylaxis for infective endocarditis were only partially followed. The most heterogeneous results emerged for prophylaxis associated with dental implants or provided prior to surgical third-molar extraction. CONCLUSIONS: The present study shows widespread antibiotic prescriptive heterogeneity among the sample of dentists analyzed, especially in conditions where international guidelines are lacking. An evidence-based consensus on prescriptive modalities in dentistry would be desirable in the near future.

Plasmon resonance biosensor for interleukin-1ß point-of-care determination: A tool for early periodontitis diagnosis.

Among pro-inflammatory cytokines, Interleukin-1ß is crucially involved in several inflammatory-based diseases and even cancer. Increased Interleukin-1ß levels in oral fluids have been proposed as an early marker of periodontitis, a broadly diffused chronic inflammatory condition of periodontal-supporting tissues, leading eventually to tooth loss. We describe the development of a portable surface-plasmon-resonance-based optical fiber probe suitably coated with an anti-Interleukin-1ß antibody monolayer. A pico-nanomolar linear range of determination was obtained in both buffer solution and saliva with a rapid (3 min) incubation and high selectivity in presence of interferents. Higher Interleukin-1ß concentration in the saliva of a periodontitis patient compared to a healthy control was determined. These measurements were validated by an automated ELISA system. Our results sustain the potential applicability of the proposed SPR-POF as diagnostic point-of-care device for real-time monitoring of salivary Interleukin-1ß, that can support early detection of oral inflammatory-based pathologies and rapid and timely therapeutic decisions.

Effects of abutment materials on peri-implant soft tissue health and stability: A network meta-analysis.

PURPOSE: This systematic review aimed to evaluate the effect of the abutment material on peri-implant soft tissue health and stability. STUDY SELECTION: An electronic and hand search was conducted until February 2022. Only prospective randomized trials (RCTs) and controlled clinical trials (CCTs) comparing titanium abutments with abutments made of different materials, with a follow-up of at least 6 months, were selected by two independent reviewers. Data on marginal bone loss (MBL) and peri-implant tissue indexes, i.e., plaque index (PI), bleeding on probing (BOP), probing depth (PD), and recession (REC), were collected. The risk of bias for RCTs and non-RCTs was evaluated according to the tool reported in the Cochrane Handbook for Systematic Reviews of Interventions and the ROBINS-I tool, respectively. Both pairwise and network meta-analyses (NMA) were performed. RESULTS: We included 18 relevant studies from 1,437 identified studies. Overall, 612 patients were treated, and 848 abutments were inserted. Five studies presented a low risk of bias. Pairwise meta-analysis showed that, as compared to titanium, zirconia abutments presented a significantly reduced MBL (0.20 mm, 95% Confidence Interval CI [0.14-0.26], P < 0.00001). No significant differences were found for the other outcomes. In the NMA, zirconia abutments demonstrated an 83.3% probability of achieving the highest rank in PI, an 87.0% in BOP, and a 65.0% in PD outcome, suggesting that zirconia abutments generally performed better than titanium and alumina abutments. CONCLUSIONS: Within the limits of the present study, zirconia abutments seem a viable alternative to titanium ones.

Comparison of Milled Full-Arch Implant-Supported Frameworks Realised with a Full Digital Workflow or from Conventional Impression: A Clinical Study.

BACKGROUND: The aim of the present study was to investigate the accuracy of a new digital impression system, comparing it to the plaster impression technique in the realization of full-arch implant-supported metal frameworks. METHODS: We took 11 scans (8 of the upper maxilla and 3 of the lower jaw) on a sample of nine patients previously rehabilitated with fixed full-arch screw-retained prostheses following the Columbus Bridge Protocol (CBP) with four to six implants (total: 51) since at least 4 months. Two impressions were taken for each dental arch: one analogic plaster impression using pick-up copings and an open tray technique and a second one using an intra-oral scanner. Two milled metal substructures were realised. The precision and passivity of the substructures were clinically analysed through the Sheffield test and endo-oral radiographs. Laboratory scans of the plaster casts obtained from an intra-oral scanner (IOS) and of the plaster casts obtained from traditional impression were compared with the intraoral scans following Hausdorff's method and an industrial digital method of optical detection to measure discrepancies. A Mann-Whitney test was performed in order to investigate average distances between surfaces after the superposition. RESULTS: The Sheffield test demonstrated an excellent passivity of the frameworks obtained through both the digital and the analogic method. In 81.81% of cases (n = 9) both substructures were found to have a perfect fit with excellent passivity, while in 18.18% (n = 2) of cases the substructures were found to have a very slight discrepancy. From the radiographic examination, no gaps between the frameworks and the implant heads or multiunit abutments were observed, with 100% accuracy. By superimposing digital files of scans according to Hausdorff's method, a statistically significant discrepancy (p = 0.006) was found between the digital scans and the digital models obtained from plaster impressions. Three-dimensional optical detection found a mean discrepancy of 0.11 mm between the analogic cast and the cast derived from the digital impression. CONCLUSIONS: The present study clinically demonstrates that milled implant-supported full-arch frameworks obtained through a digital scan and the herein described technique have an accuracy comparable to those obtained with traditional plaster impression.

Towards a point-of-care test to cover atto-femto and pico-nano molar concentration ranges in interleukin 6 detection exploiting PMMA-based plasmonic biosensor chips.

Point-of-Care tests based on biomarkers, useful to monitor acute and chronic inflammations, are required for advances in medicine. In this scope, a key role is played by pro-inflammatory cytokines, of which interleukin 6 (IL-6) is generally thought as one of the most relevant. To use IL-6 in real scenarios, detection in ultra-low concentration ranges is required. In this work, two IL-6 biosensors are obtained by exploiting the combination of the same antibody self-assembled monolayer with two different plasmonic probes. This approach has demonstrated, via experimental results, that two different IL-6 concentration ranges can be explored. More specifically, IL-6 in an atto-femto molar range can be detected via polymer-based nanoplasmonic chips. On the other hand, a pico-nano molar range is obtained by a surface plasmon resonance platform in plastic optical fibers. As a proof of concept, the detection of IL-6 at the femto molar range has been obtained in Saliva and Serum. The results show that the proposed sensing approach could be useful in developing Point-of-Care devices based on a general setup with the capability to exploit both the plasmonic biosensor chips to monitor the IL-6 in the concentration range of interest, to provide an important support for the diagnosis and monitoring of oral and systemic diseases.

Effectiveness of Hyaluronic Acid Gel Injection with and without PRGF for Management of Interdental Papillary Loss: A Randomized Clinical Trial.

BACKGROUND: To evaluate the effectiveness of hyaluronic acid (HA) gel injection with and without plasma rich in growth factors (PRGF) for the management of interdental papillary loss. METHODS: A single blinded randomized clinical trial was carried out on 21 subjects with 34 sites. Patients within the age group 18-45 years who had Class I and II papillary recession in the maxillary anterior region were selected. The sites involved were randomly assigned to Group HA alone and Group HA + PRGF. The patients were recalled 4 weeks after receiving supragingival and subgingival instrumentation. HA or HA + PRGF was injected into the defective papilla at baseline and at 3 and 6 weeks. Image based measurements of Papillary Width (PW), Papillary Deficient Height (PDH), Deficient Area (DA), Deficient Volume (DV) were registered at baseline, 3 weeks, 6 weeks and 12 weeks. A vernier caliper was used to measure the papillary depth in the impression made using additional silicone impression material pre- and post-intervention. RESULTS: There was a significant improvement in the within-group comparison of PW, PDH, DA and DV in both the groups. Group HA + PRGF showed significantly greater improvement in comparison to Group HA alone in terms of PDH, DA and DV at 6 and 12 weeks. CONCLUSIONS: Even though HA gel has already been established as a promising injectable agent in the minimally invasive treatment of interdental papillary deficiency, PRGF may also have a significant adjuvant effect when used along with HA. Further clinical studies with longer follow up duration, larger sample size and standardization of the tooth shape are required for a better understanding of the adjuvant effect of PRGF when used along with HA.

An optical fiber-based point-of-care test for periodontal MMP-8 detection: A proof of concept.

OBJECTIVES: The evaluation of salivary biomarkers has been proposed as a simple and non-invasive aid to the conventional periodontal diagnosis based on clinical-radiographic parameters. Matrix metalloproteinase-8 (MMP-8), especially in its active form, is considered one of the most reliable biomarkers of periodontitis, and point-of-care tests (POCTs) have been proposed for its clinical monitoring. In this proof-of-concept study, a novel highly sensitive POCT based on a plastic optical fiber (POF) biosensor exploiting surface plasmon resonance (SPR) to detect salivary MMP-8 is described. METHODS: A SPR-POF biosensor was functionalized with a specific antibody to develop a surface-assembled monolayer (SAM) for the detection of total MMP-8. A white light source and a spectrometer connected to the biosensor were used to quantify MMP-8 level in both buffer and real matrix (saliva) by analysing the shift of the resonance wavelength determined by the specific antigen-antibody binding upon the SAM. RESULTS: Dose-response curves by serial dilutions of human recombinant MMP-8 were realized, obtaining a limit of detection (LOD) of 40 pM (1.76 ng/ml) in buffer and 225 pM (9.9 ng/ml) in saliva and high selectivity compared to interferent analytes (MMP-2 and IL-6). CONCLUSIONS: The proposed optical fiber-based POCT was able to detect and measure total MMP-8 with high selectivity and very low LOD in both buffer and saliva. CLINICAL SIGNIFICANCE: The SPR-POF technology may be employed to create highly sensitive biosensors to monitor salivary MMP-8 levels. The possibility of specifically detecting its active, rather than total, form need to be further investigated. If confirmed and clinically validated, such a device may represent a promising tool to make an immediate, highly sensitive and reliable diagnosis of periodontitis, and to carry out a timely and targeted therapy, possibly helping to prevent the onset of local and systemic periodontitis-related complications.

Plasmonic optical fiber biosensor development for point-of-care detection of malondialdehyde as a biomarker of oxidative stress.

Numerous pieces of evidence demonstrate that oxidative stress impairs biological functions, speeds up aging, and has a role in a variety of human diseases, including systemic and oral inflammatory disorders, and even cancer. Therefore, technologies providing accurate measures of oxidative stress indicators or biomarkers appear essential in the identification/prevention of such diseases, and in their management. Particularly advantageous is the employement of point-of-care tests based on affordable and small biochips since they can quickly process biological samples and deliver results near the point of care for a prompt therapeutic intervention. Malondialdehyde (MDA) is a key byproduct of oxidative reaction and has been identified as an effective marker of oxidative stress. Herein, we describe the detection of MDA in buffer and in a complex matrix such as saliva, using a plasmonic optical fiber device combined with a highly selective anti-MDA antibody. The experimental results highlight the excellent performance of the proposed biosensor, as well as its ability to provide a low-cost point-of-care test (PoC-T) to be used in real life situations. We demonstrated that a single saliva dilution step and a short incubation time are required for the accurate detection of low concentrations of total MDA (free and conjugated). As a proof-of-concept of future biomedical applications, the method has been tested to determine MDA concentration in saliva of a periodontitis patient compared to that of a healthy control. The obtained findings represent the basis for developing PoC-Ts to be employed in monitoring oral diseases like periodontitis, oral cancers or systemic oxidative-stress associated pathologies. Conclusively, our study puts the ground for an oxidative stress biosensor widely-applicable to different scenarios.