Comparison of Periodontally Compromised Splinted Teeth and Implant Supported Fixed Partial Denture: A Three-Dimensional Finite Element Analysis on Bone Response.

Introduction - This study aimed to compare the amount and pattern of stress and strain distributed around periodontally compromised splinted teeth and the two-implant abutments supported six-unit fixed partial denture (FPD) using finite element analysis (FEA). Methods and Materials - Six mandibular anterior teeth of a dental model were scanned and the scans were transferred to 3D CAD design and finite element software. Jaw bone was also designed and the teeth were splinted by fiber-reinforced composite (FRC) band. In another model, two implants were placed at the site of canine teeth and a six-unit FPD was designed over them. Models were transferred to finite element software and after meshing and fixing, they were subjected to 100- and 200-N loads under 0 and 30° angles. Results - Apical areas and crestal bone showed the highest accumulation of stress and strain in periodontally compromised splinted teeth. Crestal bone and bone between crestal microthread and the first thread of implant body had the highest accumulation of stress and strain in the implant supported six-unit FPD. Conclusion - The results showed significantly higher shear stress, von Mises stress and von Mises strain in peri-implant bone compared with bone around periodontally compromised teeth. Increase in applied load magnified this difference. Also, a greater difference was noted in stress and strain in bone around teeth and implants when oblique load was applied.

Bacterial Microleakage at the Implant-Healing Abutment Interface in Two Different Implant Designs: Platform Switching versus Platform Matching.

This in vitro study aims to assess inward bacterial microleakage at the implant-healing abutment (IHA) interface in two different implant designs, namely platform switching (PS) and platform matching (PM). Five samples were collected from each of the PS and PM implant systems. In the first phase, healing abutments were tightened onto the implants by 10 Ncm torque. Next, IHA assemblies were immersed in an Escherichia coli (E. coli) suspension for 24 hours and 7 and 14 days. The healing abutments were then unscrewed, and samples were collected from the internal part of the implants and streak-cultured on culture media. After 1 day of incubation, the number of grown colonies was counted. In the second phase, the aforementioned steps were repeated for the assemblies that were torqued by 20 Ncm. Data were analyzed by the Kruskal-Wallis and Mann-Whitney tests (α = 0.05). The mean colony count was found to increase over time in the PM group torqued by 10 and 20 Ncm; however, this increase was only significant for 10 Ncm torque (P = 0.02). In the PS group, the colony count did not follow a certain pattern over time, neither in the 10 Ncm nor in the 20 Ncm torque. The mean colony count in the PS group was lower than that in the PM group at all time points in both torques. This difference was not significant at day 1, irrespective of torque value, but it was significant at 7 and 14 days, in both 10 and 20 Ncm torques (P < 0.05). Thus microleakage is lower in PS than PM design. The selection of a PM or PS design is a more important factor than the applied torque (10 or 20 Ncm) for reduction of bacterial microleakage in Tube-in-Tube implant systems with screw-retained connections.

In Vitro Comparison of Microbial Leakage of the Implant-Healing Abutment Interface in Four Connection Systems.

This study sought to assess microbial leakage through the implant-healing abutment interface in 4 dental implant connection systems. Ten implants of each of the 3i (double hexagon + flat to flat; group 1), IDI (internal hexagon + Morse taper; group 2), Swiss Plus (external bevel + internal octagon; group 3), and Tapered Screw-Vent (internal bevel + internal hexagon; group 4) systems were used in this in vitro, experimental study. Healing abutments were screwed to the implants with 10 Ncm torque. Implants were immersed in Escherichia coli suspension for 24 hours. Samples were taken of the internal surface of implants and cultured. The number of grown colonies was counted after 24 hours of culture and after 7 and 14 days of immersion in microbial suspension. The same was repeated with healing abutments torqued to 10 and 20 Ncm. With 10 Ncm torque, all specimens in all groups showed microleakage at one day with the highest microleakage in one sample in group 3. At 7 days, the highest microleakage was noted in one specimen in group 2. With 20 Ncm torque, group 3 showed significantly higher microleakage than other groups at 1 and 7 days (P < .05). Increasing the torque decreased microleakage in all groups except for group 3. Microbial leakage occurred in almost all implant systems in our study. In one-stage implant placement, healing abutments should be preferably torqued to 20 Ncm to minimize microleakage. Optimal torque for healing abutment insertion should be analyzed individually for each system.

Effects of Er,Cr:YSGG Laser Treatment on Human Gingival Fibroblast Attachment, Viability and Morphology of Root Surface: An In Vitro Study.

Rehabilitation of periodontal support is the main goal of therapies for periodontitis. Hand instrumentation with curettes, piezoelectric ultrasonic scalers and lasers, such as Er,Cr:YSGG, are used for this purpose. This study was designed to evaluate human gingival fibroblast viability attachment to root surfac after modification with the mentioned therapeutic alternatives. Lasers showed significantly lower cell viability after 72 hours compared to hand instrumentation and ultrasound, probably due to more irregular root surfaces after treatment.

Salivary Visfatin Concentration in Response to Non-surgical Periodontal Therapy.

INTRODUCTION: Visfatin is a pro-inflammatory cytokine that has been associated with several immunomodulating processes. The relationship between visfatin and periodontitis has been the subject of a few studies that have described visfatin as an inflammatory marker for periodontitis. However, studies on visfatin as a potential therapeutic target in periodontal diseases are scarce. In the present study, we evaluated the alterations in salivary visfatin levels in response to non-surgical periodontal treatment. MATERIALS AND METHODS: Twenty individuals with moderate to severe chronic periodontitis and twenty periodontally healthy individuals were selected for this study according to clinical parameters. Patients with chronic periodontitis were treated by non-surgical periodontal therapy. Clinical parameters were recorded and saliva samples were obtained from the control group and test group before (T1 group) and one month after periodontal treatment (T2 group). Salivary visfatin concentrations were measured by standard enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed with the statistical software SPSS, version 18. RESULTS: Visfatin was detectable in all samples. T1 and control groups were significantly different in terms of clinical parameters and visfatin levels. Visfatin concentrations were reduced significantly after non-surgical periodontal therapy. Periodontal treatment also resulted in significant reductions of all clinical parameters with the exception of clinical attachment level. CONCLUSION: The results demonstrated that salivary levels of visfatin are reduced after non-surgical periodontal therapy to the levels comparable with those found in healthy individuals. Therefore, the salivary visfatin level may have the potential to be a target marker for assessment of responses to non-surgical periodontal therapy. However, more studies with larger sample sizes are necessary to validate these findings.

Using implants for prosthodontic rehabilitation of a 4-year-old with ectodermal dysplasia.

Ectodermal dysplasia (ED) is an inherited disorder that affects ectodermally derived organs, such as teeth. Pathogenesis is thought to involve an altered epithelium-mesenchymal interaction. ED patients have oligodontia (or sometimes anodontia) in addition to other abnormalities involving the skin, sweat glands, or hair. Many different subtypes have been introduced in the literature. This article describes the case of a 4-year-old patient who, after being diagnosed with ED, was put on a treatment plan that involved mandibular implants, reshaping of the maxillary primary central incisors, and prosthetic dental rehabilitation. Due to the child's rapid growth, both dentures were changed 9 months post-treatment. Two years post-treatment, the maxillary denture was changed again and the child was placed under close supervision.

Correlation between levels of sulcular and capillary blood glucose.

AIM: The aim of this study was to evaluate the correlation between capillary blood glucose levels (CBGLs) and sulcular blood glucose levels (SBGLs) using blood obtained from gingival tissue during routine periodontal examinations to determine if sulcular blood samples can be used as a non-invasive means to diagnosis blood glucose levels. METHODS AND MATERIALS: Thirty non-diabetics and 30 diabetic patients with moderate to severe periodontitis were included in the study and subjected to routine clinical periodontal examinations. Blood was collected using a 1.6-1.8 mm diameter micro bite collection tube to transport the sample from the gingival sulci of anterior teeth following periodontal pocket probing to a test strip of a glucose self-monitoring device. As a control, capillary blood was taken with a finger-stick. Statistical analysis was performed using the Pearson's correlation coefficient and a t-test. RESULTS: The blood glucose levels in patients ranged from 58 mg/dl to 477 mg/dl, and the values of blood samples taken from gingival sulcus or finger tip of the same patient showed a very high intra-patient correlation (r =0.99, p< 0.0001). CONCLUSION: The results of this study suggest sulcular blood from a routine periodontal examination may be used for diabetes mellitus screening. CLINICAL SIGNIFICANCE: Considering 50% of diabetics remain undiagnosed, testing sulcular blood may provide a suitable method for identifying potential diabetic patients during routine dental visits since there is a correlation with capillary blood. Appropriate referrals to a physician can then be made when warranted.