Alveolar ridge splitting and simvastatin loaded xenograft for guided bone regeneration and simultaneous implant placement: randomized controlled clinical trial.

OBJECTIVES: The present study goal was to assess clinically and radiographically using simvastatin (SMV) loaded xenograft for guided bone regeneration (GBR) around simultaneously placed implants with alveolar ridge splitting in patients with horizontally atrophic jaw defect. MATERIALS AND METHODS: Randomized distribution of the twenty-two patients into two groups (11 patients each) was performed. Group I participants received alveolar ride splitting (ARS) with GBR using SMV gel mixed bone graft and a barrier membrane with simultaneous implant placement. Group II received the same treatment protocol without SMV gel. At the baseline, 6- and 9-months post-surgery, clinical and radiological alterations were assessed. RESULTS: Six months after therapy, PES records of group I were statistically significantly improved than those of group II (P < .001). Group I exhibited statistically significant expansion of the alveolar ridge over group II after 6 and 9 months (P < .001). When compared to group II over the evaluation interval between 6 and 9 months, group I demonstrated statistically substantially minimal loss of the mean marginal bone level (P < .001). At the 6- and 9-month observation periods, bone density gain was considerably higher in group I than that in group II (P < .001). CONCLUSION: Alveolar ridge splitting along with GBR-augmented SMV improve the clinical and radiographical outcomes around dental implant over GBR alone. CLINICAL RELEVANCE: Augmenting GBR with SMV in alveolar ridge splitting could boost implant osseointegration and enhance peri-implant tissue changes. CLINICAL TRIAL REGISTRATION: NCT05020405.

The impact of membrane perforation and L-PRF for vertical ridge augmentation with a xenogeneic block graft: an experimental study in a canine model.

OBJECTIVES: This study evaluated clinically and histologically the efficacy of modified perforated collagen membrane (PCM) and/or leukocyte- and platelet-rich fibrin (L-PRF) in combination with xenogeneic block bone graft in the vertical alveolar ridge augmentation. MATERIALS AND METHODS: Six adult mongrel dogs were enrolled in this randomized blinded study. After defect preparation, xenogeneic screw-fixed block graft was covered by an occlusive collagen membrane in group 1 that represented the control group (Block + CM). In group 2, L-PRF membrane was added first before top coverage by occlusive collagen membrane (Block + L-PRF + CM). Groups 3 (Block + PCM) and 4 (Block + L-PRF + PCM) were identical to the first two groups except that the occlusive collagen membrane was replaced by a perforated one. Following a healing period of 2 months, the dogs were submitted to the surgical reentry phase for clinical and histological evaluation. RESULTS: Clinically, no significant differences were found among all groups regarding vertical and horizontal ridge dimensions (p = 0.155, 0.492, respectively). Histomorphometric analysis revealed that the percentage of the total bone area and mature bone was significantly higher in group 4 (69.36 ± 2.72, 33.11 ± 5.18) compared to the control group (59.17 ± 4.27, 21.94 ± 2.86) (p = 0. 027, p = 0.029). CONCLUSION: The use of xenogenic block grafts in combination with a double-layered perforated collagen L-PRF membrane in vertical ridge augmentation appeared to improve the inductive power of this challenging defect type. CLINICAL RELEVANCE: Size and number of perforations may affect the mechanical and handling properties of the membrane.

Adjunctive effect of collagen membrane coverage to L-PRF in the treatment of periodontal intrabony defects: a randomized controlled clinical trial with biochemical assessment.

BACKGROUND: The innovation of leukocyte platelet-rich fibrin (L-PRF) has added enormous impact on wound healing dynamics especially the field of periodontal regeneration. The release of growth factors (GF) is thought to improve the clinical outcomes in infrabony defects. The aim of this study was to evaluate the clinical effect of covering L-PRF contained infrabony defects with collagen membranes (CM), and to compare their GF release profile to uncovered L-PRF defects and open flap debridement (OFD). METHODS: Thirty non- smoking patients with infrabony pockets participated to be randomly assigned to OFD group (n = 10), L-PRF group (n = 10), or L-PRF protected CM group (n = 10). Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and the radiographic defect base fill (DBF) were measured at baseline and at 6 month following surgical intervention. Gingival crevicular fluid samples were obtained on days 1, 3, 5, 7, 14, 21 and 30 days following surgery for the Platelet Derived Growth Factor-BB (PDGF-BB) and Vascular Endothelial Growth Factors (VEGF) release profile evaluation. RESULTS: For all patients, a statistically significant (P ≤ 0.05) reduction in PI, GI, PD and CAL were reported throughout the study period. Differences between the three treatment modalities were not statistically significant. PRF + CM showed a statistically significant DBF compared to OFD and L-PRF groups at follow up. Quantitative analysis of PDGF-BB and VEGF levels demonstrated a statistically significant (P < 0.001) decline between measurement intervals for all groups with no statistically significant differences between the three groups. CONCLUSION: Within the limitations of this study, L-PRF coverage with CM may augment defect base fill through its mechanical protective effect without enhancement in the release profile of VEGF and PDGF. The non-significant intergroup differences question the validity of the claimed extra physiologic concentration of GF offered by L-PRF harvests. TRIAL REGISTRATION: The present study was registered at ClinicalTrials.gov (NCT05496608), (11/08/2022).

Guided tissue regeneration of intrabony defects with perforated barrier membranes, simvastatin, and EDTA root surface modification: A clinical and biochemical study.

BACKGROUND: Perforated barrier membranes (PBM) were suggested to enhance periodontal regeneration by allowing positive charity of wanted elements from the gingival tissue side. The present study was designed to evaluate clinically and biochemically the use of PBM combined with simvastatin (SMV) gel with and without an associated EDTA gel root surface etching as a suggested option that could improve SMV availability and clinical outcomes of PBM. METHODS: Forty patients having moderate-to-severe chronic periodontitis with 40 intrabony defects were randomly divided into four treatment groups (10 sites each). Patients in group 1 received 1.2% SMV gel and covering the defect with occlusive membrane (OM). Patients in group 2 received 1.2% SMV gel and covering the defect with PBM. Group 3 received 24% EDTA root surface etching, 1.2% SMV gel, and defect coverage with OM (eOM). Patients in group 4 were treated as in group 3 but the defect was covered with PBM (ePBM). Clinical parameters were recorded at baseline before surgical procedures and were reassessed at 6 and 9 months after therapy. The mean concentration of SMV in gingival crevicular fluid (GCF) was estimated by reverse-phase high-performance liquid chromatography at days 1, 7, 14, 21, and 30. RESULTS: At 6- and 9-month observation periods, groups 3 and 4 showed a statistically significant improvement in PD reduction and CAL gain compared with groups 1 and 2. Group 4 showed a statistically significant more defect fill compared with groups 1, 2, and 3 (P ≤ .05). Group 2 showed statistically significant higher defect fill compared with group 1 and group 3 (P < .05). Bone density was significantly increased with no significant difference between the four groups at 6- and 9-month observation periods. SMV-GCF concentration in group 4 showed the highest mean concentration with no significant difference than that of group 3. CONCLUSION: The use of perforated barrier membranes in association with SMV enhances the clinical hard tissue parameters compared with occlusive ones in treating intrabony periodontal defects. Moreover, EDTA root surface treatment could enhance SMV availability in the defect area.

Regenerative potential of cultured gingival fibroblasts in treatment of periodontal intrabony defects (randomized clinical and biochemical trial).

BACKGROUND: Defective cellular elements constitute an important challenge to achieve predictable periodontal regeneration. In an attempt to improve the cellularity of periodontal defects, gingival fibroblasts were implanted without their associated extracellular elements in periodontal defects to expose them to periodontal tissue mediators. In order to investigate the regenerative potential of gingival fibroblasts translocated into periodontal defects, the present study was designed to clinically and biochemically investigate the use of gingival fibroblasts (GF) and their associated mesenchymal stem cells (GMSC) in the treatment of intrabony periodontal defects. METHODS: A total of 20 subjects were randomly divided into two groups (n = 20). Group I: ten patients were included with ten intrabony periodontal defects that received ß-calcium triphosphate (ß-TCP) followed by collagen membrane defect coverage, while group II: (10 patients) ten periodontal defects received cultured gingival fibroblasts (GF) on the ß-TCP scaffold and covered by a collagen membrane. The clinical evaluation was carried out at the beginning and at 6 months. Gingival crevicular fluid (GCF) samples were collected directly from the test sites for the quantitative measurement of PDGF-BB and BMP-2 using the ELISA kit at 1, 7, 14, and 21 days after surgery. RESULTS: Group II reported a significantly greater reduction in vertical pocket depth (VPD) and CAL gain compared with group I after 6 months. Radiographic bone gain was statistically higher in group II compared with group I. A significantly higher concentration of PDGF-BB was observed in group II on days 1, 3, and 7 compared with group I. CONCLUSIONS: Translocation of gingival fibroblasts from gingival tissue to periodontal defects could be a promising option that increases cellular elements with regeneration potential. The concept of total isolation of gingival fibroblasts using occlusive membranes must be re-evaluated.

Lycopene solid lipid microparticles with enhanced effect on gingival crevicular fluid protein carbonyl as a biomarker of oxidative stress in patients with chronic periodontitis.

Lycopene (LP), a naturally occurring carotenoid in red-coloured fruits, especially tomatoes, has a pivotal role in counteracting the deleterious effect of oxidative stress on periodontal tissues. The aim of this study is to prepare solid lipid microparticles (SLMs) encapsulating LP and to assess their biochemical and clinical effects in the management of chronic periodontitis. Optimization of SLMs was performed by assessing particle size and LP entrapment efficiency. Clinical study included 16 chronic periodontitis patients allocated into two groups, Group I was managed by scaling and root planing (SRP) and local delivery of LP loaded SLMs, while Group II was managed by SRP only. Protein carbonyl (PC) levels as a biomarker of oxidative stress and drug concentration in gingival crevicular fluid (GCF) were assessed at different time intervals. Results revealed that optimum formula of SLMs had a particle size of 77.28 µm and entrapped 98.03% of LP. SLMs recorded 30 d of drug release with no burst effect. Patients treated with LP SLMs showed significantly lower levels of PC after SRP compared to those treated with SRP only, in addition to improvement in the measured clinical parameters. In conclusion, locally delivered LP SLMs along with SRP could have a protective effect over periodontal tissues and it has the ability to decrease oxidative damage of proteins in diseased periodontium.

Shear bond, wettability and AFM evaluations on CO2 laser-irradiated CAD/CAM ceramic surfaces.

The purpose of this study is to determine the CO2 laser irradiation in comparison with sandblasting (Sb), hydrofluoric acid (Hf) and silane coupling agent (Si) on shear bond strength (SBS), roughness (Rg) and wettability (Wt) of resin cement to CAD/CAM ceramics. Sixty (CAD/CAM) ceramic discs were prepared and distributed into six different groups: group A, control lithium disilicate (Li); group B, control zirconia (Zr); group C, Li: CO2/HF/Si; group D, Li: HF/Si; group E, Zr: CO2/Sb/Si; group F, Zr: Sb/Si. Result showed significant difference between irradiated and non-irradiated in terms of shear bond strength for zirconia ceramics (p value = 0.014). Moreover, partial surface wettability for irradiated and non-irradiated ceramics. Irradiated surface demonstrated more rough surface in lithium disilicate than zirconia ceramics. CO2 irradiation could increase shear bond strength, surface roughness and wettability for both CAD/CAM ceramics.

Gingival crevicular fluid bone morphogenetic protein-2 release profile following the use of modified perforated membrane barriers in localized intrabony defects: a randomized clinical trial.

BACKGROUND: In guided tissue regenerative surgery, membrane perforations may serve as a mechanism for the passage of cells and biologic mediators from the periosteum and overlying gingival connective tissue into the periodontal defects. To test this assumption, this study was designed to evaluate levels of bone morphogenetic protein-2 (BMP-2) in gingival crevicular fluid (GCF) during the early stages of healing for sites treated with modified perforated membranes (MPMs) as compared with occlusive membranes (OMs). METHODS: Fifteen non-smoking patients with severe chronic periodontitis participated in this prospective, randomized and single-blinded clinical trial. Each patient contributed two interproximal contralateral defects that were randomly assigned to either an experimental modified perforated membrane group (15 sites) or a control occlusive membrane group (15 sites). Plaque index, gingival index, probing depth(PD), clinical attachment level (CAL) and the relative intrabony depth of the defect (rIBD) were measured at baseline and reassessed at three, six and nine months after therapy. Gingival crevicular fluid samples were collected on day 1 and 3, 7, 14, 21, and 30 days after therapy. RESULTS: The MPM-treated group showed a statistically significant improvement in PD reduction and clinical attachment gain compared to the OM control group. Similarly, rIBD was significantly reduced in MPM-treated sites as compared with those of the OM group. BMP-2 concentrations peaked in the MPM samples obtained during the early postoperative period (days 1, 3 and 7) with a statistically significant difference compared with OM-treated groups. BMP-2 levels decreased sharply in the samples obtained at days 14, 21 and 30 with non-significant higher levels in MPM samples as compared with those of OM sites. CONCLUSION: Within the limits of the present study, one can conclude that MPM coverage of periodontal defects is associated with a significant initial increase in GCF levels of BMP-2, a factor that could improve the clinical outcomes of guided tissue regenerative surgery.

Human periodontal ligament fibroblast responses to compression in chronic periodontitis.

AIM: Test whether human periodontal ligament fibroblasts (PDLFs) retain homeostatic responses to a physiological compressive force during chronic periodontitis. MATERIAL AND METHODS: Six cell lines were established from periodontally healthy individuals (H-PDLFs) and another six were cultured from patients diagnosed with chronic periodontitis (D-PDLFs). Compressive force at 150 psi was applied to H-and D-PDLFs for 3 h on 2 consecutive days. After compression, comparisons between H-and D-PDLFs were performed by gene expression analysis of IL-6, proteases and 84 inflammation-related targets using real-time PCR. RESULTS: Compression of H-PDLFs resulted in a significant increase only in MMP-1 mRNA. In contrast, the same compressive force on D-PDLFs produced significant increases in the expression of MMPs-1,-7,-9 and -16. Moreover, compression of H-PDLFs resulted in down-regulation of IL-6, while IL-6 was significantly up-regulated in compressed D-PDLFs. Compression of H-PDLFs slightly up-regulated 3 and significantly down-regulated 15 inflammation-related genes, while the same treatment strongly up-regulated 21 inflammation-related genes in D-PDLFs. CONCLUSION: These results suggest a fundamental difference in the inflammatory response of healthy versus diseased PDLFs under physiological compression. Maintenance of these characteristics in vitro suggests that these cells may be at least partly responsible for the persistence of inflammation and localized susceptibility in chronic periodontitis.

The use of integrin binding domain loaded hydrogel (RGD) with minimally invasive surgical technique in treatment of periodontal intrabony defect: a randomized clinical and biochemical study.

BACKGROUND: Periodontal regeneration faces multiple challenges, the most important being cellular insufficiency. In an attempt to improve defect cellularity, we aimed to demonstrate enhancing cellular attraction using arginine-glycine-aspartic acid (RGD) adhesion molecule legend blended hydrogel within the intrabony defects. METHODOLOGY: Forty-five intrabony defects were selected from patients with stage III or IV - grade A or B periodontitis and divided randomly into three equal groups of 15 each: group1 (G1): received minimally invasive surgical technique (MIST) alone, group2 (G2): received MIST and placebo hydrogel injection, and group3 (G3): were treated with MIST and RGD hydrogel injection. Primary outcomes 6 months following therapy were; defect base fill (DBF) and defect width measurement (DW); secondary outcomes were clinical attachment level (CAL), pocket depth (PD), plaque index (PI), gingival index (GI), and biochemical analysis of bone morphogenetic protein (BMP-2) evaluated at 1,7,14 and 21 days following therapy. RESULTS: Significant improvements in DBF, CAL, and PD were observed in the three studied groups 6 months following therapy compared to baseline (p<0.05). A significant improvement in DBF was reported in G3 compared to G1 and 2 (p=0.005). Additionally, a significantly higher CAL gain was reported in G3 compared to that of G1 (p=0.02). Group 3 was associated with a significantly higher level of BMP-2 compared to G1 and G2 in all reported periods. CONCLUSION: RGD peptide carried on a hydrogel delivery agent and contained with a minimally invasive flap could be a reliable option in improving the outcomes of periodontal therapy.

Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet Laser for Root Conditioning and Reduction of Postoperative Morbidity in the Treatment of Gingival Recession Defects: A Randomized Controlled Clinical Trial.

Objective: This clinical trial evaluates the effect of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) root surface biomodification and laser harvesting of de-epithelialized gingival graft (DGG) on root coverage clinical outcomes and postoperative morbidity, and compares this to the conventional blade-harvested DGG method without Er,Cr:YSGG root surface biomodification in treatment of Miller's class I, II gingival recessions (GR). Background: The application of laser technology to enhance tooth root coverage clinical outcomes as well as the impact of laser on postoperative morbidity after harvesting autogenous soft tissue grafts requires further research. Methods: This study is a randomized, single-blinded controlled trial, including 24 volunteers with isolated GR defects. They were allocated into three treatment groups to receive one of the following three interventions: blade-harvested DGG (control group: B-DGG); Er,Cr:YSGG-harvested DGG and root surface biomodified [test 1 group: L-laser-harvested DGG (L-DGG)/laser root biomodification (LRB)]; and B-DGG and Er,Cr:YSGG root surface biomodification (test 2 group: B-DGG/LRB). Clinical and radiographic parameters were recorded at baseline (1 week before surgery) and 3, 6, and 9 months postoperatively. Results: Root coverage did not show a statistically significant difference between control and test groups. Statistically significant differences were found for Visual Analog Scale on the day of surgery and day 3 and 4 postoperatively, as well as pain medication on the day of surgery favoring the L-DGG group. Conclusions: The use of Er,Cr:YSGG laser in root surface biomodification improved root coverage outcomes at 9 months. Even these changes were not statistically significant from the control group; the L-DGG technique was associated with decreased postoperative morbidity in the palatal donor site.

Antimicrobial Efficacy of Charcoal vs. Non-charcoal Toothbrushes: A Randomized Controlled Study.

AIM: To assess the efficacy of the antimicrobial properties of charcoal vs. non-charcoal toothbrushes and the level of bacterial contamination in the oral cavity using a charcoal toothbrush. MATERIALS AND METHODS: This was a randomized, double-blind controlled study in which both male and female subjects aged from 18 to 35 were included (n = 30; 15 males and 15 females). The subjects were selected from (students) of Riyadh Elm University in Riyadh, Saudi Arabia. Subjects were informed about the study and signed the consent form before participation. From January to April 2019, subjects were given charcoal and non-charcoal toothbrushes. RESULTS: The Wilcoxon signed rank test showed that there was a significant difference in bacterial counts between non-charcoal and charcoal toothbrushes (P = 0.000). Of the subjects, 70% showed a decrease in the number of bacterial counts while 30% showed no increase in bacterial counts. There was a statistically significant decrease in the number of bacteria in the gingival crevicular fluid (GCF) with charcoal treatment (P < 0.001). Of the subjects, 96.6% showed a decrease in the count of bacteria in GCF after using a charcoal toothbrush. Only 3.3% of the subjects had the similar counts of bacteria in GCF after using the charcoal toothbrush. CONCLUSION: The study demonstrates that charcoal toothbrushes reduce bacterial contamination and the poor effects on oral health after 1 week of use.

A novel marginal periosteal pedicle graft as an autogenous guided tissue membrane for the treatment of intrabony periodontal defects.

OBJECTIVE: The aim of the present study was to clinically examine the effects of a novel marginal periosteal pedicle graft (MPP) as a guided tissue membrane for treating proximal intrabony defects in comparison to a an open flap debridement. MATERIAL AND METHODS: Fifteen patients with severe chronic periodontitis and no systemic diseases participated in this prospective, controlled clinical trial. Each subject contributed matched pairs of interproximal two- or three-walled intrabony defects. Baseline clinical examination included plaque index (PlI), gingival index (GI), bleeding on probing (BOP), probing depth (PD) and clinical attachment level (CAL) of selected sites and were performed two weeks following completion of cause-related therapy. Radiographic measurements were also recorded to ascertain the radiographic depth of the defect. Each pair of periodontal defects were randomly assigned into the experimental group G1, marginal periosteal pedicle graft (MPP) guided tissue membrane or the control open flap debridement group, G2. In the MMP, partial thickness flaps were elevated at the vestibular surface of the tooth adjacent to the interproximal defect to harvest a 4 mm marginal pedicle periosteal graft. Exposed root surfaces were root planed and the remaining bony walls of the selected defect were degranulated prior to the periosteal pedicle barrier membrane being rotated to cover the intrabony defect. Sites representing the control group were treated with only open flap debridement. Clinical and radiographic parameters were recorded at 3, 6 and 9 months after surgery for treatment outcome evaluation. RESULTS: Baseline data showed no differences in any of the investigated parameters, suggesting parameters were balanced between the two groups. Both experimental and control groups showed significant improvements in all of the soft and hard tissue parameters when compared to baseline (p < 0.001). At nine months, the experimental MPP group showed significant improvement in PD reduction, CAL gain and intrabony defect reduction when compared to the control (p < 0.01). In the MPP group, the mean reduction in PD was 3.8 mm, mean CAL gain was 3.4 mm and mean reduction in intrabony defect was 2.2 mm. In sites treated with open flap DEBRIDEMENT, the mean PD reduction was 2.5 mm, CAL gain was 2.0 mm and mean reduction in intrabony defect was 0.6 mm. CONCLUSION: Within the limits of this study, it can be concluded that the placement of a marginal periosteal pedicle graft as a barrier membrane significantly improved clinical and radiographic parameters of deep intrabony defects and proved superior to OPEN FLAP DEBRIDEMENT alone.

Platelet-derived growth factor BB treated osteoprogenitors inhibit bone regeneration.

The study evaluates the ability of osteoprogenitors treated with platelet-derived growth factor BB (PDGF-BB) delivered on vinyl styrene microbeads (VSM) to regenerate rat calvarial critical-size defects (CSDs). Fetal rat calvarial cells were cultured and tested for their ability to attach to VSM using scanning electron microscopy. Twenty-five rats were equally divided into 5 groups; a negative control (GPI), vinyl styrene microbeads (GPII), PDGF-BB (GPIII), VSM plus osteoblastic progenitors (GPIV), and VSM plus PDGF-BB treated osteoblastic progenitors (GPV). CSDs were created and reconstructed according to the mentioned study design. After 16 weeks, animals were sacrificed and defect areas evaluated for bone regeneration. Cells attached to the microbeads; however, their morphology and topography were affected by the PDGF-BB. Transplanting the VSM/cells constructs to CSDs revealed significant reduction of bone regeneration upon pretreatment of the cells with PDGF-BB. However, short-term application of PDGF-BB to CSD stimulated bone regeneration. The ability of osteoprogenitor cells to regenerate bone was significantly reduced upon pretreatment with PDGF-BB in vitro. However, adding PDGF-BB at the time of surgery had stimulated bone regeneration.

CO2 laser dentin surface treatment most effectively increased ceramic shear bond strength.

BACKGROUND AND AIMS: The purpose of this study is to determine the effect of CO2 laser irradiation in comparison with sandblasting (Sb), hydrofluoric acid (Hf) and silane coupling agent (Si) on shear bond strength (SBS) of resin cement to CAD/CAM ceramics bonded to dentin. MATERIAL AND METHODS: Forty-eight (CAD/CAM) ceramic discs were prepared and grouped by material, i.e. lithium disilicate (Emax CAD) and zirconia ceramic (Emax ZirCAD), distributed into four different groups: group A, lithium disilicate (Li) CO2/HF/Si; group B, Li: HF/Si; group C, zirconia (Zr) CO2/Sb/Si; group D, Zr: Sb/Si. RESULTS: It was shown significant difference between irradiated and non-irradiated groups in terms of shear bond strength for zirconia ceramics (p value = 0.039). CONCLUSION: CO2 laser irradiation increases shear bond strength for both CAD/CAM ceramics bonded to dentin.

Dimensional evaluation of blood clot gap distances within intrabony defects following grafting and EDTA root surface treatment-experimental study in dogs.

BACKGROUND: Because it is important to establish and maintain a firm blood clot to the surrounding tissues within the intrabony lesion; we have to investigate the potentials of different materials in resisting clot retraction that disrupt clot adhesion to the root surface. This study was designed to measure the gap distance created by clot retraction within the defect following intrabony defects grafting with and without root surface EDTA etching. METHODS: Eight mongrel dogs with surgically created acute-chronic bilateral mandibular interproximal intrabony defects in the premolar-molar areas were enrolled in this study (total 8 defects per dog). Intrabony defects were divided into four groups, the first group (OFD): control open flap debridement, the second group, (EDTA treated defects) in which debridement of the defects was followed by two minute root surface etching with a neutral 24% EDTA gel followed by two minute copious saline irrigation, the third group (only grafted defects): defects received closely packed ß-TCP of a particle size ranged from 150 to 500 mm, and the fourth group, (Graft + EDTA treated defects): defects were etched for 2 minutes with a neutral 24% EDTA gel and saline irrigation followed by intrabony defect fill of ß-TCP. Twenty four hours post treatment, animal euthanasia was carried out for histomorphometric analysis of the tooth and root side gap distances. RESULTS: EDTA treated group and EDTA + graft group showed statistically significant lower degree of clot shrinkage compared to both the control and only grafted group. Clot shrinkage in EDTA treated group showed no significant difference from that of the EDTA + graft group (p = 0.197). OFD and only grafted groups were found to show statistically higher clot retraction percnetage compared to both EDTA and EDTA+graft groups. CONCLUSION: following intrabony defect debridement, blood clot undergoes clot retraction creating a micro gap with the root surface. EDTA root surface etching before graft application into the defect area significantly reduced the amount of gap distance.

Disilicate Dental Ceramic Surface Preparation by 1070 nm Fiber Laser: Thermal and Ultrastructural Analysis.

Lithium disilicate dental ceramic bonding, realized by using different resins, is strictly dependent on micro-mechanical retention and chemical adhesion. The aim of this in vitro study was to investigate the capability of a 1070 nm fiber laser for their surface treatment. Samples were irradiated by a pulsed fiber laser at 1070 nm with different parameters (peak power of 5, 7.5 and 10 kW, repetition rate (RR) 20 kHz, speed of 10 and 50 mm/s, and total energy density from 1.3 to 27 kW/cm²) and the thermal elevation during the experiment was recorded by a fiber Bragg grating (FBG) temperature sensor. Subsequently, the surface modifications were analyzed by optical microscope, scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDS). With a peak power of 5 kW, RR of 20 kHz, and speed of 50 mm/s, the microscopic observation of the irradiated surface showed increased roughness with small areas of melting and carbonization. EDS analysis revealed that, with these parameters, there are no evident differences between laser-processed samples and controls. Thermal elevation during laser irradiation ranged between 5 °C and 9 °C. A 1070 nm fiber laser can be considered as a good device to increase the adhesion of lithium disilicate ceramics when optimum parameters are considered.

The use of integrin binding domain loaded hydrogel (RGD) with minimally invasive surgical technique in treatment of periodontal intrabony defect: a randomized clinical and biochemical study

Abstract Periodontal regeneration faces multiple challenges, the most important being cellular insufficiency. In an attempt to improve defect cellularity, we aimed to demonstrate enhancing cellular attraction using arginine-glycine-aspartic acid (RGD) adhesion molecule legend blended hydrogel within the intrabony defects. Methodology Forty-five intrabony defects were selected from patients with stage III or IV - grade A or B periodontitis and divided randomly into three equal groups of 15 each: group1 (G1): received minimally invasive surgical technique (MIST) alone, group2 (G2): received MIST and placebo hydrogel injection, and group3 (G3): were treated with MIST and RGD hydrogel injection. Primary outcomes 6 months following therapy were; defect base fill (DBF) and defect width measurement (DW); secondary outcomes were clinical attachment level (CAL), pocket depth (PD), plaque index (PI), gingival index (GI), and biochemical analysis of bone morphogenetic protein (BMP-2) evaluated at 1,7,14 and 21 days following therapy. Results Significant improvements in DBF, CAL, and PD were observed in the three studied groups 6 months following therapy compared to baseline (p<0.05). A significant improvement in DBF was reported in G3 compared to G1 and 2 (p=0.005). Additionally, a significantly higher CAL gain was reported in G3 compared to that of G1 (p=0.02). Group 3 was associated with a significantly higher level of BMP-2 compared to G1 and G2 in all reported periods. Conclusion RGD peptide carried on a hydrogel delivery agent and contained with a minimally invasive flap could be a reliable option in improving the outcomes of periodontal therapy.

Effects of EDTA gel preconditioning of periodontally affected human root surfaces on chlorhexidine substantivity - an SEM study.

BACKGROUND: Infection control is an important requirement during the early stages of periodontal healing. This study was performed to assess the preconditioning effect of EDTA gel on chlorhexidine (CHX) substantivity to periodontally involved root surfaces. METHODS: Eighty patients with severe chronic periodontitis were enrolled in this study. Following cause-related therapy, patients were divided randomly into four groups. Each group consisted of 20 subjects with one tooth that was diagnosed as hopeless and designated for extraction. In group 1 (G1), selected periodontal pockets were filled with a placebo gel in a silica base for 2 minutes. Exposed roots in group 2 (G2) were etched for 2 minutes with a neutral EDTA conditioning agent, followed by pocket fill with the placebo gel. Pockets in group 3 (G3) were filled with 0.12% CHX digluconate gel in a silica base. Exposed roots in group 4 (G4) were etched for 2 minutes with a neutral EDTA conditioning agent, followed by pocket fill with the CHX gel. Four teeth from each group were extracted immediately and at 3, 12, 24, and 48 hours for SEM evaluation. RESULTS: G1 and G2 specimens showed no evidence of silica adherent to any of the examined root surfaces. At 3 hours following CHX gel application, G3 specimens showed marked reduction in CHX-coated silica. At 24 and 48 hours following EDTA and CHX gel application, G4 specimens demonstrated adherent CHX-coated silica particles despite the reclogging of the tubule orifices. CONCLUSION: EDTA and CHX gel root conditioning is a valuable regimen that improves CHX substantivity to periodontally involved root surfaces.