Efficacy of different protocols of non-surgical periodontal therapy in patients with type 2 diabetes: A systematic review and meta-analysis.

The aim of the present systematic review of the literature and meta-analysis was to evaluate the efficacy of different protocols of NSPT without any adjunctive therapy in subjects with type 2 diabetes, by considering clinical and patient-centered outcomes. For the purposes of the study randomized controlled clinical trials with more than 3-month follow-up were searched in MEDLINE, EMBASE, and Cochrane Central. Then the articles were screened for inclusion and considered based on the protocols adopted, the outcome measure, follow-up, and the level of glycemic control. A total of 23 articles about 22 studies were included. NSPT was more effective than just oral hygiene measures/no treatment in reducing periodontal probing depth (PPD) and clinical attachment loss (CAL) at 3 months (0.47 mm [0.29-0.65 mm] and 0.50 mm [0.24-0.76 mm], respectively) and 6 months (0.56 mm [0.28-0.84 mm] and 0.45 mm [0.13-0.77 mm], respectively for PPD and CAL) follow-up (very low and low level of evidence). The meta-analysis found no evidence of a difference between full-mouth disinfection versus quadrant protocol clinical outcomes (very low level of evidence). One study found no evidence of a difference in periodontal clinical response between good versus poor glycemic control. Based on the results of the present research NSPT protocols could be considered more efficacious than others in terms of clinical outcomes in subjects with type 2 diabetes. Moreover, NSPT resulted in efficacious improvement of periodontal parameters and HbA1c levels compared to no treatment or oral hygiene instructions alone.

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVES: Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence. MATERIALS AND METHODS: Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control. RESULTS: Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence. CONCLUSION: Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

The efficacy of adjunctive periodontal therapies during supportive periodontal care in patients with residual pockets. A systematic review and meta-analysis.

While it is well-established that patients that develop signs of relapsing periodontitis in supportive periodontal care (SPC) will need to repeat subgingival instrumentation of the residual pockets, less certainty is available in terms of which protocol should be followed and whether the use of adjunctive therapies or physical agents might provide additional benefits to repeated instrumentation alone. The aim of this systematic review was therefore to assess whether repeating subgingival instrumentation in combination with adjunctive therapies (other than antimicrobials) might provide a significant benefit in terms of pocket closure, probing pocket depth (PPD) reduction or clinical attachment level (CAL) gain in patients during SPC with residual/relapsing pockets. Four databases were searched to identify randomized controlled trials (RCTs) and controlled clinical trials (CCTs) with a minimum follow-up of 3 months that investigated the use of adjunctive therapies (other than antimicrobials) in case of residual/relapsing pockets in patients in SPC since at least 3 months. Data extraction and risk of bias assessment were performed in the studies meeting the inclusion criteria and meta-analysis was performed when ≥3 studies assessing the same adjunctive therapy were identified. 12 studies (2 CCTs and 10 RCTs) were included for qualitative analysis. Meta-analysis was performed only for 3 studies on the adjunctive use of photodynamic therapy (PDT) and it indicated a nonsignificant benefit compared to the placebo in terms of PPD reduction and CAL gain at 3 months (weighted mean difference 0.07 and -0.03, respectively) and at 6 months of follow-up (weighted mean difference -0.09 and -0.18, respectively). While antiseptics did not provide significant benefits, one study on probiotics and one on the use of vitamin D and calcium supplementation showed significant improvements in periodontal parameters. There is currently insufficient/poor evidence to determine the efficacy of adjunctive strategies (other than antimicrobials) to improve the outcomes of SPC in case of residual/relapsing pockets.

Comparison between tensile characteristics of various suture materials with two suture techniques: an in vitro study.

OBJECTIVE: The first objective of the present study was to evaluate the tensile strength and elongation to failure of commonly used suture materials in oral surgery. As a secondary objective, it was aimed to make a comparison between two different suture techniques within the same suture materials. MATERIALS AND METHODS: Eight different suture materials with 3-0 gauge (silk, polytetrafluoroethylene, polypropylene, polyester, polyglactin 910, polyglycolic acid, poliglecaprone 25, polydioxanone) underwent tensile testing for maximum load of failure and elongation rate. All strands were tied by one investigator on the experimental platform using the surgeon's knot plus additional square knots in both simple suture and horizontal mattress suture techniques. Prepared specimens were examined using a microtensile testing device before (baseline) and after 3, 7, and 14 days' immersion in artificial saliva. RESULTS: Statistical analysis of the current study revealed that the tensile strength for polyglycolic acid, polyglactin 910, polypropylene, and silk sutures was significantly lower at day 3 than at the baseline. By day 14, polyglycolic acid and polyglactin 910 showed a significant reduction in tensile strength for both techniques. While polydioxanone obtained the highest tensile strength and elongation values in both techniques, polytetrafluoroethylene showed the most stable tensile strength even with the lowest value. Tensile strength in simple suture techniques was almost twice than that of horizontal mattress suture technique for each specimen. CONCLUSIONS: Polyglycolic acid and polyglactin 910 were considerably sensitive to immersion time. Polydioxanone demonstrated optimum performance during each immersion period among the tested materials, whereas polytetrafluoroethylene was the most stable. CLINICAL RELEVANCE: The selection of the most proper suture material remains challenging for clinicians. The present study provides relevant information for clinicians to guide them in their choice of the suitable material. In this context, clinicians can benefit from the use of polydioxanone for its high tensile strength regardless of the suture technique used, whereas polytetrafluoroethylene shows a long-term stability. The strength and stability differences among suture materials and techniques need to be considered before making an informed decision.

The effect of polyethylenglycol gel on the delivery and osteogenic differentiation of homologous tooth germ-derived stem cells in a porcine model.

OBJECTIVES: The aim of this study was to investigate if bone regeneration can be promoted by homologous transplantation of STRO-1 sorted (STRO-1+) porcine tooth germ mesenchymal stem cells (TGSCs) with the combination of polyethylenglycol (PEG)-based hydrogel and biphasic calcium phosphate (BCP) scaffolds. MATERIAL AND METHODS: TGSCs were isolated from impacted third molars of domestic pigs. Nine critical-sized defects were created as (1) untreated defect; filled with (2) autogenous bone; (3) BCP + PEG; (4) BCP + PEG + unsorted TGSCs; (5) BCP + unsorted TGSCs; (6) BCP + PEG + STRO-1-sorted TGSCs; (7) BCP + STRO-1-sorted TGSCs; (8) BCP + PEG + osteogenic induced unsorted TGSCs; and (9) BCP + PEG + osteogenic induced STRO-1-sorted TGSCs in 20 domestic pigs. CM-DiI labelling was used to track cells in vivo. Histomorphometric assessment of new bone formation was achieved by toluidine blue O staining and microradiography after 1, 2, 4 and 12 weeks posttransplantation. RESULTS: Complete healing was achieved in all defects although defects with PEG hydrogel presented better bone formation while STRO-1+ and unsorted TGSCs showed similar ability to form new bone after 12 weeks. Transplanted cells were seen in defects where PEG hydrogel was used as carriers in contrast to defects treated with cells and only bone grafts. CONCLUSIONS: PEG hydrogel is an efficient carrier for homologous stem cell transplantation. TGSCs are capable of promoting bone healing in critical-sized defects in combination with bone graft and PEG hydrogel. CLINICAL RELEVANCE: This study provides information about the importance of the delivery vehicle for future translational stem cell delivery approaches.

Dentin-Pulp Tissue Regeneration Approaches in Dentistry: An Overview and Current Trends.

Conventional treatment approaches in irreversible pulpitis and apical periodontitis include the disinfection of the pulp space followed by filling with various materials, which is commonly known as the root canal treatment. Disadvantages including the loss of tooth vitality and defense mechanism against carious lesions, susceptibility to fractures, discoloration and microleakage led to the development of regenerative therapies for the dentin pulp-complex. The goal of dentin-pulp tissue regeneration is to reestablish the physiological pulp function such as pulp sensibility, pulp repair capability by mineralization and pulp immunity. Recent dentin-pulp tissue regeneration approaches can be divided into cell homing and cell transplantation. Cell based approaches include a suitable scaffold for the delivery of potent stem cells with or without bioactive molecules into the root canal system while cell homing is based on the recruitment of host endogenous stem cells from the resident tissue including periapical region or dental pulp. This review discusses the recent treatment modalities in dentin-pulp tissue regeneration through tissue engineering and current challenges and trends in this field of research.

A Current Overview of Scaffold-Based Bone Regeneration Strategies with Dental Stem Cells.

Bone defects due to trauma or diseases still pose a clinical challenge to be resolved in the current tissue engineering approaches. As an alternative to traditional methods to restore bone defects, such as autografts, bone tissue engineering aims to achieve new bone formation via novel biomaterials used in combination with multipotent stem cells and bioactive molecules. Mesenchymal stem cells (MSCs) can be successfully isolated from various dental tissues at different stages of development including dental pulp, apical papilla, dental follicle, tooth germ, deciduous teeth, periodontal ligament and gingiva. A wide range of biomaterials including polymers, ceramics and composites have been investigated for their potential as an ideal bone scaffold material. This article reviews the properties and the manufacturing methods of biomaterials used in bone tissue engineering, and provides an overview of bone tissue regeneration approaches of scaffold and dental stem cell combinations as well as their limitations.

Influence of different surface treatments and universal adhesives on the repair of CAD-CAM composite resins: An in vitro study.

STATEMENT OF PROBLEM: The repairability of computer-aided design and computer-aided manufacturing (CAD-CAM) composite resins might be adversely affected by the high degree of matrix polymerization that occurs during their manufacturing process. However, information on their repairability is lacking. PURPOSE: The purpose of this in vitro study was to evaluate the microtensile bond strength of CAD-CAM composite resins subjected to simulated repair procedures by using varying surface treatments and universal adhesives. MATERIAL AND METHODS: Four different CAD-CAM blocks (Brilliant Crios, Lava Ultimate, Shofu Block HC, and Vita Enamic) were thermocycled (5000 times, 5/55 °C) and divided into 4 groups according to the surface treatment: control, 9% hydrofluoric acid etching, aluminum oxide airborne-particle abrasion, and tribochemical silica airborne-particle abrasion. After surface treatments, the surface roughness was measured with a nanoindenter and further examined with scanning electron microscopy. After the application of 3 different universal adhesives (Clearfil Universal Bond, Prime&Bond Universal, and Single Bond Universal), the specimens were subjected to a simulated repair process with composite resin. Bonded specimens were cut into 1 mm2 beams, and microtensile bond strength values were determined until failure at a crosshead speed of 0.5 mm/min. The bond strength data were analyzed with 3-way analysis of variance, and surface roughness data were analyzed with 2-way analysis of variance tests. Pairwise analyses were performed with the Tukey test (α=.05). RESULTS: All surface treatments effectively improved repair microtensile bond strength values compared with the control (P<.05). Aluminum oxide airborne-particle abrasion had similar mean bond strength values compared with tribochemical silica airborne-particle abrasion (P>.05). Among the CAD-CAM blocks treated with hydrofluoric acid etching, Vita Enamic had the highest mean bond strength values. The highest mean microtensile bond strength repair values with the highest cohesive failure rates were found with the silane-containing universal adhesive (Single Bond Universal). CONCLUSIONS: Surface treatment with aluminum oxide airborne-particle abrasion and tribochemical silica airborne-particle abrasion produced successful repair results for aged resin nanoceramics, whereas hydrofluoric acid etching can be used for aged hybrid ceramic repair. Silane-containing universal adhesive reported increased bond strength. Application of universal adhesive after surface treatment is recommended to increase repair strength.

Dental Stem Cells in Bone Tissue Engineering: Current Overview and Challenges.

The treatment of bone that is impaired due to disease, trauma or tumor resection creates a challenge for both clinicians and researchers. Critical size bone defects are conventionally treated with autografts which are associated with risks such as donor site morbidity and limitations like donor shortage. Bone tissue engineering has become a promising area for the management of critical size bone defects by the employment of biocompatible materials and the discovery of novel stem cell sources. Mesenchymal stem cells (MSCs) can be isolated with ease from various dental tissues including dental pulp stem cells, stem cells from apical papilla, dental follicle stem cells, stem cells from human exfoliated deciduous teeth, periodontal ligament stem cells, gingival stem cells and tooth germ derived stem cells. Outcomes of dental MSC mediated bone tissue engineering is explored in various in vivo and in vitro preclinical studies. However, there are still obscurities regarding the mechanisms underlying in MSC mediated bone regeneration and challenges in applications of dental stem cells. In this review, we summarized dental stem cell sources and their characterizations, along with currently used biomaterials for cell delivery and future perspectives for dental MSCs in the field of bone tissue engineering. Further efforts are necessary before moving to clinical trials for future applications.

3D extraoral morphometric changes after implant surgery: an exploratory pilot study using stereophotogrammetry.

OBJECTIVE: This pilot study aimed to evaluate, for the first time, the changes in facial tissues following the placement of a single dental implant. METHOD AND MATERIALS: Patients were scanned with a 3D facial scanner (3dMD) before implant surgery, immediately after surgery (T1), at 7 days postoperatively (T2), and at the impression stage (T3). Acquired images were processed using the 3dMDvultus (3dMD) software program and volume differences and linear depth measurements were calculated to determine the morphometric changes over time. A total of 11 patients were included in the analyses. Descriptive statistics were employed to analyze the data. RESULTS: The volumetric changes and maximum depth differences indicated an initial increase, followed by a progressive decrease in tissue volume after implant placement in the area of the surgery. The volume change values ranged between 2.5 and 3.9 cm3 for T1, whereas for T2, the volume change decreased to a range of 0.8 to 1.8 cm3. Maximum depth differences ranged between 2.06 and 2.80 mm in the soft tissues immediately after the implant surgery and reduced to around 2.01 to 0.55 mm at the impression stage. The amount of painkiller used was not related to the magnitude of linear depth measurements at any assessed time point. CONCLUSION: There was a longitudinal decrease in soft tissue volume and depth difference in extraoral soft tissues in the region of implant placement after surgery up to 6 weeks. The use of a facial scanner is a promising noninvasive method to monitor 3D morphometric changes after implant surgery.

Effects of calcium silicate-based cements on odonto/osteogenic differentiation potential in mesenchymal stem cells.

The objective of this study was to evaluate the biological effects and odonto/osteogenic differentiation potential of Biodentine, NeoMTA Plus and TheraCal LC in tooth germ-derived stem cells (TGSCs). TGSCs were exposed to the material extracts. Biocompatibility was tested with MTS cell proliferation assay. Odonto/osteogenic differentiation was assessed with alkaline phosphatase (ALP) activity and mRNA gene expressions (RUNX2, DSPP and DMP-1). Scanning electronic microscopy/energy-dispersive X-ray (SEM/EDX) analysis and pH analysis were also performed for the materials. Data were evaluated using the one-way ANOVA and Tukey's tests. TGSCs remained viable after 7 days of incubation with all tested materials. Biodentine and NeoMTA Plus showed high ALP activity and increased expression of RUNX2, DSPP and DMP-1 compared to that of TheraCal LC. All materials can induce odonto/osteogenic differentiation of MSCs in various levels. Biocompatibility and odonto/osteogenic differentiation potential of Biodentine and NeoMTA Plus are similar and superior to that of TheraCal LC.

The cytotoxic effects of various endodontic irrigants on the viability of dental mesenchymal stem cells.

This study aimed to evaluate cytotoxic effects of various irrigation solutions used in regenerative endodontic treatments (RETs) on mesenchymal stem cells, and further examine the long-term effect of hypochlorous acid (HOCl) on the cell viability and alkaline phosphatase (ALP) activity. Stem cells were exposed to various concentrations of NaOCl, EDTA, chlorhexidine (CHX), etidronic acid (HEDP)/NaOCl combination and HOCl. HOCl was tested for its effects on ALP activity up to 21 days. Additionally, cell viability was measured fluorescently using calcein AM. The most cytotoxic irrigant was CHX even with the lowest concentration. NaOCl and HEDP/NaOCl with 1:100 dilution decreased viability to around 40%. HOCl showed the lowest cytotoxicity among all tested irrigants. HOCl also showed no significant reduction in ALP activity compared with the controls. The cytotoxicity of endodontic irrigants was time and concentration dependent. HOCl demonstrated promising results regarding viability and ALP activity, since RETs require host stem cell survival.

Influence of Abutment Design on Stress Distribution in Narrow Implants with Marginal Bone Loss: A Finite Element Analysis.

PURPOSE: The aim of this study was to determine the effect of solid (one-piece) and two-piece abutments on the stress profile of narrow implants with marginal bone loss. MATERIALS AND METHODS: Solid and two-piece abutments were connected to a conical internal octagon-connection implant (3.3 mm in diameter, 10 mm in length) and restored with a single crown. Three-dimensional finite element analysis was used to simulate the stress distribution in implant models with different levels of marginal bone resorption (0, 1, 2, and 3 mm). The effect of the design variables under increased bone resorption scenarios, including abutment screw length and diameter, was assessed. Static loading was applied to determine the mechanical response of the implant and cortical and trabecular bone. RESULTS: Marginal bone resorption levels dominated the mechanical response under static loading conditions. A marginal bone loss of 3 mm significantly increased stress values in the implant vicinity and abutment screw. Both abutment designs displayed similar stress distribution in the surrounding bone, but lower stress values were observed in the implant body with two-piece abutments. The abutment screw length was more effective in the resultant stress, as the longer screws reduced the stress in the implants. CONCLUSION: Marginal bone resorption magnitude is the crucial parameter in biomechanics to determine the mechanical behavior. As bone loss increases, resultant stress around implants under mastication forces may lead to implant failure, regardless of abutment type.

Impact of peri-implant bone resorption, prosthetic materials, and crown to implant ratio on the stress distribution of short implants: a finite element analysis.

The purpose of this study was to determine the effects of prosthetic materials and crown/implant (C/I) ratio on short implants with a marginal bone resorption. Three-dimensional finite element analysis was used to simulate stress distribution under static loading in non-resorption and resorption scenarios (3-mm vertical bone loss) in implants restored with single crowns and C/I ratios of 1:1, 1.5:1, and 2:1 were evaluated. Different crown materials were used: porcelain-fused to metal, porcelain-fused to zirconia, monolithic zirconia, and zirconia-based crown veneered with indirect composite resin. The C/I ratio, the peri-implant bone resorption, and the loading conditions were the key factors affecting the generated stress in short implants. In non-resorption models, von Mises stress ranged between 50 and 105 MPa whereas in resorption models, the values ranged from 168 to 322 MPa, both increasing with the higher C/I ratio under oblique forces. Under axial loading, the C/I ratio did not influence the stress values as the presence of resorption was the only parameter increasing, 57 MPa for the non-resorption models and 101 MPa for the resorption models, respectively. Preference of a prosthetic material was ineffective on the distribution of stress in the bone and implant structure under static loading in any models. The peri-implant bone resorption and a higher C/I ratio in short implants increase the stress values under both axial and oblique forces, whereas the crown material does not influence stress distribution in the surrounding bone and implant structure.

Influence of STRO-1 selection on osteogenic potential of human tooth germ derived mesenchymal stem cells.

Mesenchymal stem cells derived from the human tooth germ (hTGSCs) are a heterogeneous cell population that can differentiate into osteogenic, neurogenic, and adipogenic lineages. The aim of this study was to compare the osteogenic differentiation capacity of STRO-1 positive (STRO-1+) hTGSCs and unsorted heterogeneous hTGSCs and to establish if STRO-1+ cells are more committed to osteogenic differentiation. HTGSCs were isolated from impacted third molar tooth germ tissues of adolescents, and a subpopulation of STRO-1+ hTGSCs was obtained by fluorescence-activated cell sorting. STRO-1+, STRO-1 negative (STRO-1-), and unsorted cells were cultured in osteogenic and standard culture media to compare their capacity to differentiate towards osteoblastic lineage. Cells were tested for proliferation rates, alkaline phosphatase activity, and amounts of accumulated calcium. Gene expression levels of the RUNX2, osteocalcin, and osteonectin genes were analyzed with real time PCR. Mineralization and osteogenic protein expression were examined by using von Kossa staining and confocal microscopy. Our results indicated that osteogenically induced cell populations showed greater mineralization capacity than non-induced cells. However, expression levels of early and late osteogenic markers were not significantly different between STRO-1+ and unsorted cells. In conclusion, the selection by STRO-1 expression does not yield cells with osteogenic capacity higher than that of the heterogeneous hTGSC population. Cell sorting using osteogenic markers other than STRO-1 might be beneficial in obtaining a more sensitive osteogenic sub-population from unsorted heterogenous hTGSCs.