Bone Defect Depth Research Articles

Effect of mineralized dentin matrix on the prognosis of bone defect and retained root after coronectomy.

To investigate the impact of mineralized dentin matrix (MDM) on the prognosis on bone regeneration and migration of retained roots after coronectomy. Patients were divided into three groups based on the type of bone graft after coronectomy: Group C (n = 20, collagen), Group T (n = 20, tricalcium phosphate (TCP) + collagen), and Group D (n = 20, MDM + collagen). CBCT scans, conducted immediately and 6 months after surgery, were analyzed using digital software. Primary outcomes, including changes in bone defect depth and retained root migration distance, were evaluated 6 months after surgery. After 6 months, both Groups D and T exhibited greater reduction of the bone defect and lesser retained root migration than Group C (p < 0.001). Group D had greater regenerated bone volume in the distal 2mm (73 mm3 vs. 57 mm3, p = 0.011) and lesser root migration (2.18mm vs. 2.96mm, p < 0.001) than Group T. The proportion of completely bone embedded retained roots was also greater in Group D than in Group C (70.0% vs. 42.1%, p = 0.003). MDM is an appropriate graft material for improving bone defect healing and reducing retained root migration after coronectomy. MDM is an autogenous material prepared chairside, which can significantly improve bone healing and reduce the risk of retained root re-eruption. MDM holds promise as a routine bone substitute material after M3M coronectomy.

Uso de proteínas derivadas de la matriz del esmalte combinado con injerto óseo para el tratamiento de defectos intraóseos: Resumen estructurado de revisiones sistemáticas (revisión FRISBEE)

Introduction: The use of enamel matrix-derived proteins (EMD) has increased in recent years due to their tissue-inducing properties that support periodontal regeneration. This study is an overview of systematic reviews with FRISBEE methodology on the use of EMD alone or combined with autologous bone graft materials (BGM) in the treatment of intrabony defects. Materials and Methods: A systematic search in the Epistemonikos database was performed. RevMan 5.3 and GRADEpro were used for data analysis and presentation Results: Four systematic reviews and two clinical trials were identified. All studies analysed change in probing depth, clinical attachment level, gingival margin level and bone defect depth (all changes in favour of EMD+BGM groups: mean difference (MD): 0.37 mm more, MD: 0.7 mm more, MD: 0.3 mm less, MD: 0.75 more, respectively). Conclusions: Adding autologous bone graft to EMD to treat intrabony defects showed better results, but not a relevant clinical difference compared to the use of EMD alone. Keywords: Dental enamel proteins; Bone transplantation; Autologous transplantation; Alveolar bone loss; Periodontal diseases; Bone regeneration.

Retrograde Study Using Radiographic Comparison of Bone Fill Observed after Guided Tissue Regeneration by the Type of Periodontal Bone Defect

Background and Objectives: The current study aimed to compare the extent of bone growth achieved after guided tissue regeneration (GTR) based on the location and nature of the initial periodontal lesion. Materials and Methods: The study sample included 80 patients who underwent GTR at Kyungpook National University Dental Hospital since 2012 and were radiologically followed up for at least 2 years after treatment. The patients were divided into four groups based on the location (maxilla and mandible) and nature (furcation involvement and intrabony defects) of the lesion. Differences in bone levels before and after treatment were analyzed. Additionally, a comparison of outcomes based on the type of bone graft material used was conducted. Statistical analysis included a comparison of groups using a t-test, assuming equal variance. Results: The proportion of bone growth observed in the maxillary furcation, mandibular furcation, maxillary intrabony, and mandibular intrabony lesions was 26%, 22%, 31%, and 34%, respectively. No statistically significant differences in the amount of bone fill were observed between the groups. However, a significant positive correlation was found between the initial depth of the bone defect and the amount of bone fill observed after treatment. Conclusions: Contrary to previous evidence, the current study observed no significant differences in the amount of bone fill after GTR based on the location and nature of the lesion. Furthermore, the amount of bone regenerated was directly proportional to the initial depth of the alveolar bone defect.

Clinical and Radiological Benefits of Hyaluronic Acid in Periodontal Infrabony Defects: A Systematic Review and Meta-analysis

Purpose:There is no consensus on the clinical and radiological benefits of hyaluronic acid (HA) in patients with periodontitis having infrabony defects. Hence, this study examined the effects of HA in periodontitis patients with infrabony defects through a comprehensive systematic review process.Methodology:A systematic literature search was performed using PubMed/Medline, Scopus, Embase and Cochrane Library from inception to March 2022. Randomized or non-randomized clinical trials and single-arm clinical trials that assessed the clinical and radiological benefits of HA in periodontitis patients with infrabony defects with a minimum of 6 months follow-up were included in this study. Surgical regenerative therapy was considered as the comparator. The Cochrane risk of bias assessment tool and Downs and Black checklist was used for the quality assessment of randomized and non-randomized interventional studies, respectively. A subgroup and sensitivity analyses were performed to explore the heterogeneity and robustness of the findings, respectively.Results:A total of 13 out of 725 studies were included in this systematic review, of which 9 were considered for meta-analysis. The meta-analysis indicated significant benefits of HA in terms of reduction in probing pocket depth (SMD: 1.12 mm; 95% CI: 0.60-1.65; 9 studies), bone defect depth (SMD: 1.04mm; 95%CI: 0.62-1.47; 3 studies) and gain in clinical attachment level (1.04 mm; 95% CI: 0.33-2.47; 8 studies). Overall, the quality of included studies was good.Conclusion:The current evidence indicates that the administration of HA in the periodontal regenerative treatment of infrabony defects was significantly effective in increasing clinical attachment levels and reducing probing pocket and bone defect depth.

Clinical and Radiological Benefits of Hyaluronic Acid in Periodontal Infrabony Defects: A Systematic Review and Meta-analysis

Purpose: There is no consensus on the clinical and radiological benefits of hyaluronic acid (HA) in patients with periodontitis having infrabony defects. Hence, this study examined the effects of HA in periodontitis patients with infrabony defects through a comprehensive systematic review process. Methodology: A systematic literature search was performed using PubMed/Medline, Scopus, Embase and Cochrane Library from inception to March 2022. Randomized or non-randomized clinical trials and single-arm clinical trials that assessed the clinical and radiological benefits of HA in periodontitis patients with infrabony defects with a minimum of 6 months follow-up were included in this study. Surgical regenerative therapy was considered as the comparator. The Cochrane risk of bias assessment tool and Downs and Black checklist was used for the quality assessment of randomized and non-randomized interventional studies, respectively. A subgroup and sensitivity analyses were performed to explore the heterogeneity and robustness of the findings, respectively. Results: A total of 13 out of 725 studies were included in this systematic review, of which 9 were considered for meta-analysis. The meta-analysis indicated significant benefits of HA in terms of reduction in probing pocket depth (SMD: 1.12mm; 95%CI: 0.60-1.65; 9 studies), bone defect depth (SMD: 1.04mm; 95%CI: 0.62-1.47; 3 studies) and gain in clinical attachment level (SMD: 1.40 mm; 95%CI: 0.33-2.47; 8 studies). Overall, the quality of included studies was good. Conclusion: The current evidence indicates that the administration of HA in the periodontal regenerative treatment of infrabony defects was significantly effective in increasing clinical attachment levels and reducing probing pocket and bone defect depth.

The optimal size of screw for using cement-screw technique to repair tibial defect in total knee arthroplasty: A finite element analysis

Cement can be reinforced with cancellous screws for repairing tibial defect in total knee arthroplasty (TKA). However, it is still unknown which size (diameter, length) of screws is better, and the purpose of this study was to perform a finite element analysis (FEA) to determine it. Twelve FEA models were set to represent the cement-screw technique with different diameters (3.5 mm, 5 mm and 6.5 mm) and lengths (20 mm, 25 mm, 30 mm and 35 mm). Contact stresses on the surface of cancellous bone in different areas were calculated. Compared to screws with diameter of 3.5 mm, stresses on the surface of bone defect reduced 5.75% of 5 mm and 10.68% of 6.5 mm for the screw length of 20 mm, 4.23% of 5 mm and 9.16% of 6.5 mm for 25 mm, 6.65% of 5 mm and 12.30% of 6.5 mm for 30 mm, and 5.05% of 5 mm and 12.16% of 6.5 mm for 35 mm. Compared to screws with diameter of 5 mm, stresses on the surface of defect reduced 5.24%, 5.15%, 6.05%, and 7.49% of 6.5 mm for the screw length of 20, 25, 30, and 35 mm. However, it did not show any significant difference in other comparisons. For the treatment of tibial defect in TKA with cement-screw technique, longer screw may not achieve better stability, but the thicker screw can reduce more stresses on the surface of tibial defect and achieve better stability. However, the depth of bone defect must be considered when making a choice.

Network meta-analysis of platelet-rich fibrin in periodontal intrabony defects.

To evaluate the effect of platelet-rich fibrin alone or in combination with different biomaterials for the treatment of periodontal intra-bony defect. Up to April 2022, Cochrane library, Medline, EMBASE, and Web of Science databases were searched for randomized clinical trials. The outcomes of interest were probing pocket depth reduction, clinical attachment level gain, bone gain, and bone defect depth reduction. Bayesian network meta-analysis with 95% credible intervals was calculated. Thirty-eight studies with 1157 participants were included. Platelet-rich fibrin alone or platelet-rich fibrin +biomaterials showed a statistically significant difference when compared with open flap debridement (p < 0.05, low to high certainty evidence). Neither biomaterials alone nor platelet-rich fibrin +biomaterials showed a statistically significant difference when compared to platelet-rich fibrin alone (p > 0.05, very low to high certainty evidence). Platelet-rich fibrin +biomaterials showed insignificant differences as compared to biomaterials alone (p > 0.05, very low to high certainty evidence). Allograft +collagen membrane ranked the best in probing pocket depth reduction while platelet-rich fibrin +hydroxyapatite ranked the best in bone gain. It seems that (1) platelet-rich fibrin with/without biomaterials were more effective than open flap debridement. (2) Platelet-rich fibrin alone provides a comparable effect to biomaterials alone and platelet-rich fibrin +biomaterials. (3) Platelet-rich fibrin +biomaterials provide a comparable effect to biomaterials alone. Although allograft +collagen membrane and platelet-rich fibrin +hydroxyapatite ranked the best in terms of probing pocket depth reduction and bone gain respectively, the difference between different regenerative therapies remains insignificant, and therefore, further studies are still needed to confirm these results.

Minimal invasiveness in nonsurgical periodontal therapy.

Periodontal treatment is quickly moving towards a philosophy consisting of a less invasive approach. In this context, minimally invasive nonsurgical therapy (MINST) is a promising option. This paper reviews the concepts behind minimal invasiveness in nonsurgical periodontology and reports the state-of the art evidence for this topic. Instruments used and protocols suggested for these applications are introduced and discussed. The original papers reviewed show probing pocket depth (PPD) reductions and clinical attachment level (CAL) gains ranging from 2 to 4 mm between baseline and 6 months to 5 years posttreatment for intrabony defects and from 1.5 to 3 mm between baseline and 2-6 months of follow-up for full-mouth results. These clinical outcomes are accompanied by statistically significant reductions in radiographic bone defect depth and increases in intrabony defect angles posttreatment. Wound healing mechanisms following MINST are presented, and clinical applications and directions for future research are suggested.

Comparative evaluation of demineralized freeze-dried bone allograft with and without concentrated growth factor membrane in the treatment of periodontal intrabony defects: a randomized controlled clinical trial.

The current study's aim was to evaluate and compare demineralized freeze-dried bone allograft (DFDBA) with and without concentrated growth factor (CGF) membrane in the treatment of periodontal intrabony defects on both a clinical and radiographic level. 30 stage III grade B periodontitis patients with bilateral intrabony defects were involved in the split mouth randomized controlled trial, and they received either DFDBA alone (control group) or DFDBA plus CGF membrane treatment (test group). At baseline and 6 and 12months, the gingival index (GI), plaque index (PI), probing pocket depth (PPD), clinical attachment level (CAL), and gingival recession (GR) were assessed, whereas cone beam computed tomography was used to assess the bone defect height (BDH), vertical bone loss (VBL), bone defect depth (BDD), mesio-distal bone defect width (MDBDW), bucco-lingual bone defect width (BLBDW), and bone defect volume (CBCT) at baseline and 12months. The radiographic measures BDH, BDD, MDBDW, BLBDW, and BDV in the test group likewise showed a higher reduction in PPD and gain in CAL than the control group. The results of the intergroup comparison showed that the test group had statistically significant differences in BDH, BDD, and MDBDW. The data show that the test group achieved better results, with greater reductions in PPD, gains in CAL, and decreases in BDH, BDD, MDBDW, BLBDW, and BDV. The use of concentrated growth factor in conjunction with demineralized freeze-dried bone allograft may be suggested for the treatment of periodontal intrabony defects.

Prognostic factors affecting periodontal regenerative therapy using recombinant human fibroblast growth factor-2: A 3-year cohort study.

IntroductionFibroblast growth factor-2 (FGF-2) has been reported to promote periodontal tissue regeneration. However, no study has investigated the long-term prognosis of periodontal regenerative therapy using FGF-2 to date. The aim of this study was to observe the long-term outcomes as well as to investigate the factors affecting the prognosis of periodontal regenerative therapy using FGF-2.MethodsSixty intrabony defects were prospectively investigated for three years after periodontal regenerative therapy with recombinant human FGF-2 (rhFGF-2) by evaluating probing pocket depth (PPD) and radiographic bone defect depth (RBD). The factors influencing RBD were assessed by conducting a multivariate linear regression analysis after adjusting for confounders.ResultsThe mean age of the participants was 62.4 ± 13.4 years, and baseline PPD and RBD were 6.1 ± 1.9 mm and 4.5 ± 1.8 mm, respectively. At six months, one year, and three years after surgery, PPD and RBD had significantly improved to 4.2 ± 1.7, 3.7 ± 1.4, 4.0 ± 1.9 mm and to 3.08 ± 2.05, 2.73 ± 1.90, 2.51 ± 2.15 mm, respectively. At the three-year examination, a significant positive association was deteced between RBD reduction and RBD at baseline, while the association was not significant between RBD reduction and the radiographic bony angle, number of bony walls of the defect, or the furcation involvement at baseline.ConclusionsrhFGF-2 was effective for alveolar bone regeneration in patients with periodontitis and maintained the improved parameters over the three-year observation period. The radiographic bone defect depth at baseline was found to be the factor affecting the periodontal regenerative therapy using rhFGF-2 in the intrabony defects.Trial registration numberUMIN000027979.

An exploratory clinical trial to evaluate the safety and efficacy of combination therapy of REGROTH® and Cytrans® granules for severe periodontitis with intrabony defects.

IntroductionCurrently, flap operation (FOP) using REGROTH® (0.3% basic fibroblast growth factor [FGF-2]) is the standard treatment for periodontal regenerative therapy in Japan. However, the periodontal tissue regenerative effect with REGROTH® monotherapy is inadequate for severe alveolar bone defects. Therefore, in this study, we evaluated the safety and effectiveness of periodontal regenerative therapy for patients with severe periodontitis using REGROTH® (test medicine) combined with Cytrans® Granules (test device: carbonated apatite granules), which is a new artificial bone.MethodsThe study participants included 10 patients with severe periodontitis (mean age: 47.4 years). All participants provided written informed consents. In each patient, the intrabony defect site (mean bone defect depth: 5.7 mm) was defined as the test site. FOP was performed for the test site after the baseline investigation; moreover, the test medicine and test device were administered simultaneously. Furthermore, the observation of subjects’ general condition and test sites was conducted and the blood, urine, and periodontal tissue tests were performed up to 36 weeks after FOP. The rate of bone increase (%), clinical attachment level (CAL), probing pocket depth (PPD), bleeding on probing (BOP), tooth mobility (Mo), width of keratinized gingiva (KG), gingival recession (REC), gingival index (GI), and plaque index (PlI) were evaluated during the periodontal tissue investigation.ResultsAs the primary endpoint, no adverse events related to the test medicine and test device occurred during the entire observation period of this study. Regarding the secondary endpoints, there was a significant increase in new alveolar bone (p = 0.003) and CAL acquisition (p = 0.001) as well as decrease in PPD (p = 0.002) and BOP (p = 0.016) at 36 weeks after administration of the test medicine and test device compared with the preoperative values. Furthermore, at 36 weeks after surgery, the Mo, GI, and PlI decreased to preoperative levels at 40%, 60%, and 30% of sites, respectively. However, at 36 weeks after surgery, there was no difference in KG and REC compared with their preoperative values.ConclusionsThe safety of periodontal regenerative therapy using the test medicine in combination with the abovementioned test device was confirmed. In addition, it was suggested that this periodontal regenerative therapy is effective for tissue regeneration in severe alveolar bone defects.This clinical trial was conducted after registering and publicizing as a specified clinical trial in the Japan registry of clinical trials (jRCTs051190045).

THE APPLICATION OF STEM CELLS IN TISSUE ENGINEERING FOR THE REGENERATION OF PERIODONTAL DEFECTS IN RANDOMIZED CONTROLLED TRIAL: A SYSTEMATIC REVIEW AND META-ANALYSIS.

To systematically evaluate the application of stem cells in tissue engineering for regeneration of periodontal defects and to provide a basis for clinical application. PubMed, The Cochrane Library, EMbase, SinoMed, CNKI and Wanfang database were searched for randomized controlled trial (RCT) studies on periodontal defect regeneration using bone marrow mesenchymal stem cells, adipose tissue-derived stem cells, periodontal ligament stem cells (PDLSCs), dental pulp stem cells (DPSCs), gingival mesenchymal stem cells, stem cells from apical papilla and other odontogenic stem cells. Chinese and English literature as of May 9, 2021 (without limitation on retrieve starting date) were searched, and included RCT studies were followed for at least 3 months. Two reviewers independently screened the literature, extracted basic research information, the situation of the research object and outcome measures including probing depth (PD), clinical attachment level (CAL), bone defect depth (BDD) and gingival recession (GR). Cochrane Handbook for Systematic Reviews of Interventions (Version 5.1.0) was used to evaluate bias risk in included studies and Meta-analysis was performed using RevMan 5.4 software. A total of 182 teeth were included in 7 RCT studies. The experimental group was treated with stem cell tissue engineering technology (87 cases), and the control group was treated with conventional periodontal regeneration therapy without stem cell (95 cases). In the meta-analysis, a significant difference between experimental and control groups was found for PD [mean difference (MD) = -0.66, 95% CI (-1.11, -0.22), P = .004], CAL [MD = -1.11, 95% CI (-1.45, -0.77), P < .00001], BDD [MD = -0.99, 95% CI (-1.42, -0.57), P < .00001] and GR [MD = -0.35, 95% CI (-0.62, -0.07), P = .01]. By observing the 4 outcome indicators of periodontal tissue regeneration, the improvement of CAL was the best, while the improvement of GR was poor. In the subgroup analysis of follow-up time, PD improved best at 6 months compared with other follow-up times [MD = -1.07, 95% CI (-1.58, -0.55), P < .0001]. However, in the subgroup analysis of CAL, BDD and GR, there was no statistical significance among follow-up time. Compared with conventional periodontal regeneration therapy, the application of stem cells in tissue engineering exhibits a significant advantage in promoting periodontal defect regeneration and allows for complete periodontal regeneration possibly. Due to limitations related to the number and quality of the included studies, additional large-sample and high-quality clinical studies are needed to support future meta-analyses.

Added effect of 1% topical alendronate in intra-bony and inter-radicular defects as part of step II periodontal therapy: a systematic review with meta-analysis and trial sequential analysis

BackgroundThis systematic review and meta-analysis aimed to investigate the role of alendronate combined with step 2 of periodontal therapy in reducing probing pocket depth, improving clinical attachment level, and reducing bone defect depth in intra-bony and inter-radicular defects.MethodsRCTs with more than 6 months follow-up were included in this study. Risk of bias assessment was performed using the Cochrane collaboration tool. In addition, meta-analysis and trial sequential analysis were used to aggregate the available evidence.ResultsSeven studies met the inclusion criteria and were included in the systematic review. Topical application of alendronate during second step of periodontal therapy significantly improved PD and CAL.ConclusionLocal application of alendronate may confer a beneficial effect when applied during step II of periodontal therapy even if long term studies are needed to confirm these results.Clinical relevanceConsidering the emerging role of host-inflammatory response in treatment of periodontitis and the antiresorptive and osteostimulative properties of bisphosphonates, several studies are focusing on the role of alendronate as an addition to non-surgical periodontal therapy.

Influence of aging on periodontal regenerative therapy using enamel matrix derivative: A 3‐year prospective cohort study

To investigate the influence of chronological aging on periodontal regenerative therapy (PRT) outcomes with enamel matrix derivative (EMD). In total, 253 intra-bony defects (151 patients) including 44 furcation involvement were prospectively investigated for 3 years after regenerative therapy with EMD by evaluating probing pocket depth (PPD), clinical attachment level (CAL), and radiographic bone defect depth (RBD). The influence of age on these outcomes was assessed using multilevel regression analyses adjusting for confounders. Participants' mean age was 55.9 ± 12.3 years (range: 22-85). Baseline PPD, CAL, and RBD were 6.14 ± 1.82, 7.22 ± 2.14, and 5.08 ± 2.04 mm, respectively. Significant improvement was observed with PPD reductions of 2.84 ± 1.73 and 2.87 ± 1.87 mm, CAL gains of 2.40 ± 1.87 and 2.47 ± 1.89 mm, and RBD gains of 1.76 ± 1.98 and 2.39 ± 2.41 mm at 1- and 3-year examinations, respectively. At the 1-year examination, multivariate analysis revealed a significant negative association between age and improvement in PPD and CAL (coefficients: -0.13, -0.23 mm per 10 years). However, by the 3-year examination, no significant association was noted between age and improvement in PPD, CAL, or RBD. Although the statistical difference was detected with age at 1-year examination, PRT with EMD significantly improved clinical outcomes on long-term observation, irrespective of the patient's age. UMIN000039846.

Influence of preformed bone defects on key pathogens and bone loss during experimental peri-implantitis formation in a canine model.

To determine the impact of experimentally preformed peri-implant crater-shaped bone defects on the evolution of in situ microbiota and development of bone defects compared to those induced over time by ligature placement only. Implants were installed in the mandibles of eight dogs. Standardized bone defects were preformed in four test animals but not in the other four control animals, prior to implant (3.3 mm × 8 mm) installation. After 2 months of healing, peri-implantitis was induced with silk ligatures in both groups for 2 months. Microbial samples were obtained from implants and teeth for analysis at three time points (qPCR), and the average depths of the bone defects were measured. At the baseline, the total marker load of periodontal-pathogenic bacteria (TML) for teeth accounted for 5.2% (0-17.4%). After implant healing, TMLs for implants and teeth were comparable (7.1% [0.3-17.4%]). The TML of both groups was 3.5%, 2 months after ligature placement. Bone defects had a mean depth of 1.84 mm at preformed defects and 1.64 mm at control sites (P > 0.05). Preformed defects in the test group showed comparable results to the control group in terms of TML, the incidence of periodontal-pathogenic bacteria, and bone defect depth.

Successful Management of Peri-Implantitis around Short and Ultrashort Single-Crown Implants: A Case Series with a 3-Year Follow-Up.

Introduction and Aim In case of peri-implantitis, resective surgery is contraindicated for short and ultrashort implants, limiting the treatment options to regenerative surgery or to implant removal. This retrospective case series presents the clinical and radiographic outcomes of a surgical regenerative procedure to treat peri-implantitis around short and ultrashort implants. Materials and Methods The study is a retrospective evaluation of patients suffering from peri-implantitis and those who underwent access flap surgery, concomitant chemical and mechanical decontamination of implant surface, and bone grafting using a self-hardening mixture of bone substitutes and biphasic calcium sulfate. No membranes were applied to cover the grafting material, and primary tension-free closure was achieved. The retrospective protocol was reviewed and approved by the Ethics Committee for Clinical Sperimentation (CESC) of Verona and Rovigo, Italy (based in the University of Verona) (Prog. 1863CESC. Date of approval: 2018-07-04). Results 15 patients (17 implants) have been diagnosed with peri-implantitis after a mean follow-up of 24 months after loading. Implant length was between 5 and 8 mm. 8 patients (10 implants) had a history of periodontitis. At baseline, the mean PD (probing pocket dept) at the deepest site was 8.12 mm, with an average mBI (modified bleeding index) of 2.35 and a mean BD (bone defect depth) of 3.04 mm. At the 3-year follow-up, the CSR was 100%, the mean mBI was 0.88 (average reduction: −1.47), the mean PD was 3.35 mm (mean PD reduction: 4.77 mm), and the mean bone defect was reduced by 1.74 mm, with a mean bone fill of 55%. Conclusions The results of the present case series suggest that if accurate surface decontamination is achieved, high survival rate and good clinical and radiographic results can be obtained after 3 years. However, only the histological examination could confirm the growth of new bone in direct contact with the implant surface or if the grafted material only fills the space left by the peri-implant defect.

Influence of proximal two-wall bone defect on periodontal ligament stresses under normal occlusal forces

Objective: To study the influence of two-wall bone defect on periodontal ligament stresses under normal occlusal forces, and to analyze the influence of depth and width of bone defect to periodontal ligament stresses. Methods: Three-dimensional finite element models of teeth, periodontal ligament and alveolar bone were created based on cone beam CT images. Proximal two-wall bone defect with different depths (bone defect occupies one third, two thirds, and full length of root) and widths (bone defect occupies one fourth, two fourths, three fourths and full width of buccal lingual width) were simulated by modifying the elastic modulus of elements within defect areas. Occlusal forces with magnitudes of half of the maximum occlusal forces were applied to the model at an angle of 45° to the long axis of tooth, and equivalent stresses of periodontal ligament were analyzed. Results: In the model of no bone defect, the equivalent stresses of periodontal ligament of incisors, canines, premolars and molars were 2.88, 2.31, 8.67 and 7.53 MPa respectively. The equivalent stresses of periodontal ligament increased with the enlargement of depth and width of bone defect. The equivalent stresses of periodontal ligament with maximum bone defect in both depth and width for incisors, canines, premolars and molars were 4.47, 3.62, 11.66 and 8.72 MPa respectively. In the model of width of bone defect was consistent and bone defect develops vertically, the increments of equivalent stresses of periodontal ligament were significantly greater in the early stage bone defect model (from no defect to one third of root length bone defect) than that in the later stage bone defect model (from two thirds to full length of root length bone defect). In the model of bone defect depth was consistent and bone defect develops transversely, the increments of equivalent stresses of periodontal ligament in the early stage bone defect model (from no defect to one fourth of buccal lingual width bone defect) were significantly smaller than that in the later stage bone defect model (from three fourths to full width of buccal lingual width bone defect). Conclusions: Bone defect with shallow depth and that with large width would increase periodontal ligament stresses. Therefore, more attention should be paid to occlusion evaluation and adjustment for teeth with shallow and wide two-wall bone defect.

Mechanical and chemical implant decontamination in surgical peri-implantitis treatment: preclinical "invivo" study.

The aim of the present study was to evaluate the effect of a titanium brush and chemical agents following surgical treatment of experimental peri-implantitis. Six implants were installed in the mandible of eight beagle dogs (unit of analysis) 3months after tooth extraction. Experimental peri-implantitis was induced 3months later. The defects were randomly allocated in three treatment groups: (a) TiBrush(™) +sodium hypochlorite+chlorhexidine (TBH), (b) TiBrush(™) +chlorhexidine (TB), (c) an ultrasonic device+chlorhexidine (US). The distal implant in each hemimandible was used as control, and no treatment was done. Clinical and histological measurements were performed after 3months of healing. All treatment procedures resulted in statistically significant improvements of all clinical parameters. Histomorphometrical analysis revealed no statistically significant differences between treatment groups in terms of woven bone height (primary outcome). However, there were differences between test and control groups in terms of inflammation, bone defect depth and bone refill without differences between TBH and TB groups. Resolution of peri-implantitis after access surgery and decontamination of peri-implant surfaces with TiBrush(™) with or without sodium hypochlorite is possible. However, the concomitant use of sodium hypochlorite has minor effect on treatment outcomes.

Treatment of periodontal intrabony defects using autologous periodontal ligament stem cells: a randomized clinical trial.

BackgroundPeriodontitis, which progressively destroys tooth-supporting structures, is one of the most widespread infectious diseases and the leading cause of tooth loss in adults. Evidence from preclinical trials and small-scale pilot clinical studies indicates that stem cells derived from periodontal ligament tissues are a promising therapy for the regeneration of lost/damaged periodontal tissue. This study assessed the safety and feasibility of using autologous periodontal ligament stem cells (PDLSCs) as an adjuvant to grafting materials in guided tissue regeneration (GTR) to treat periodontal intrabony defects. Our data provide primary clinical evidence for the efficacy of cell transplantation in regenerative dentistry.MethodsWe conducted a single-center, randomized trial that used autologous PDLSCs in combination with bovine-derived bone mineral materials to treat periodontal intrabony defects. Enrolled patients were randomly assigned to either the Cell group (treatment with GTR and PDLSC sheets in combination with Bio-oss®) or the Control group (treatment with GTR and Bio-oss® without stem cells). During a 12-month follow-up study, we evaluated the frequency and extent of adverse events. For the assessment of treatment efficacy, the primary outcome was based on the magnitude of alveolar bone regeneration following the surgical procedure.ResultsA total of 30 periodontitis patients aged 18 to 65 years (48 testing teeth with periodontal intrabony defects) who satisfied our inclusion and exclusion criteria were enrolled in the study and randomly assigned to the Cell group or the Control group. A total of 21 teeth were treated in the Control group and 20 teeth were treated in the Cell group. All patients received surgery and a clinical evaluation. No clinical safety problems that could be attributed to the investigational PDLSCs were identified. Each group showed a significant increase in the alveolar bone height (decrease in the bone-defect depth) over time (p < 0.001). However, no statistically significant differences were detected between the Cell group and the Control group (p > 0.05).ConclusionsThis study demonstrates that using autologous PDLSCs to treat periodontal intrabony defects is safe and does not produce significant adverse effects. The efficacy of cell-based periodontal therapy requires further validation by multicenter, randomized controlled studies with an increased sample size.Trial RegistrationNCT01357785 Date registered: 18 May 2011.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-016-0288-1) contains supplementary material, which is available to authorized users.

Radiographic Bone Changes Around Immediately Placed Immediately Restored Dental Implants In Periodontally Compromised Sites

Background: The aim of this study is to evaluate radiographic success of immediately restored dental implants placed immediately after extraction of periodontally compromised anterior teeth. Methods: In this prospective clinical trial human study, ten patients were selected from outpatient clinic of the Department of Oral Medicine, Periodontology, Oral Diagnosis, and Radiology, Faculty of Dentistry, Tanta University. Teeth were extracted as a result of sever periodontal destruction, followed by immediate implant placement and immediate implant restoration. Implant survival, bone level was evaluated for each patient at 6, 9 and 12-month follow-up period. Subtraction radiography was performed to compare the baseline image from 12 months follow up period image. Results: The survival rates of the immediately placed implants in the present study were 100%. Results showed significant reduction of the bone defect depth at 6, 9 and 12 months when compared to immediate post-operative record. Also massive increase of the mean bone density scores at 12 months when compared to immediate post operative record. Conclusion: Based on the results of this clinical trial, placement of implants immediately in fresh extraction sockets affected by periodontal disease followed by immediate restoration may be a valid operative technique that leads to predictable results if adequate preoperative and postoperative care is taken.