Effect of Apical Root Canal Perforation Size on Push-out Bond Strength of Glass Fiber Dowels.

AIM: To evaluate in vitro effect of apical root canal perforation size on push-out bond strength of glass fiber dowels cemented to sound or perforated root canals using two different adhesive systems. MATERIALS AND METHODS: A total of 120 human-extracted intact upper central incisors were selected. Teeth were sectioned 3 mm coronal to cement enamel junction, and the remaining root received endodontic root canal therapy. The roots were divided into two experimental groups according to the root condition: either sound (n = 40) or apically perforated (n = 80). Dowel spaces were prepared for all specimens to a depth of 10 mm. Roots were restored with glass fiber dowels. The experimental group was further subdivided into four subgroups (n = 20) according to the adhesive system used and apical perforation size: group I, perforated root 2 mm apically, dowel cemented using total-etch adhesive cement; group II, perforated root 2 mm apically, dowel cemented using self-etch adhesive cement; group III, perforated root 4 mm apically, dowel cemented using total-etch adhesive cement; and group IV, perforated root 4 mm apically, dowel cemented using self-etch adhesive cement. The control group, sound root, was divided into two subgroups: group I, sound root, dowel cemented using total-etch adhesive cement, and group II, sound root, dowel cemented using self-etch or total-etch adhesive cement. Each root was then cut horizontally, and root segments were prepared to be tested. The bond strength between dowel and dentin was measured with universal testing machine using a push-out test. The two-way analysis of variance (ANOVA) was used to analyze the data and post hoc Tukey's test (α = 0.05). RESULTS: Root canal perforation and the type of adhesive system used resulted in significant differences in push-out bond strength (p < 0.05). Regardless of root canal perforation size, glass fiber dowels in normal root canals had significantly higher mean bond strength values (9.2 ± 1.4 MPa) compared with perforated root canals (6.1 ± 1.4 MPa). Also, self-etch protocol had significantly higher mean bond strength values (9.1 ± 1.3 MPa) compared with total-etch protocol (6.2 ± 2.1 MPa). CONCLUSION: The apical root perforation size caused a direct effect on the bond strength of the glass fiber dowels cemented to dentin by reducing the bond strength values to the root dentin regardless of the adhesive system used. CLINICAL SIGNIFICANCE: Prior to perforation repair, dentist or endodontist should evaluate the perforation size to predict the treatment outcome.

Ridge Augmentation with Autogenous Bone Graft and Expanded Polytetrafluoroethylene Membrane using Tenting Screw: A Randomized Controlled Clinical Trial.

BACKGROUND: The study aims to compare non-tenting screw and tenting with a reinforced expanded polytetrafluoroethylene (ePTFE) membrane in horizontal ridge augmentation using an autogenous bone graft. MATERIAL AND METHODS: A randomized controlled clinical trial was conducted between 150 patients needing dental implants. The participants were randomly divided into three study groups; group 1: ridge augmentation using non-resorbable ePTFE membrane only, group2: ridge augmentation using an ePTFE and tenting screw with bone graft Bio-Oss mixed with autogenous bone particles and group 3 (control): ridge augmentation with a bone block. The initial measurement was done at the bone crest at the exact implant site and 10 mm apical to the bone crest. Repeat measurements were recorded after 6 months of healing. Statistical analysis was performed by paired sample t-test and two-way analysis of variance (ANOVA). Statistical significance was considered at p <0.05. RESULTS: There was a significant gain in the bone in all the three groups postsurgery. Group 3 recorded higher reading at the crest and apical sites when compared to groups 1 and 2 at 6 months (late measurements). The difference in the percentage gain was statistically significant after adjusting for age as well as the initial measurement. The highest gain was seen in group 3 followed by groups 2 and 1. CONCLUSION: The membrane with tenting screw group and block bone groups had a significantly higher increase in measurement when compared to the membrane only group. Tenting screw with Bio-Oss can be used in patients with autogenous bone at the donor site. CLINICAL SIGNIFICANCE: Tenting screws in combination with membranes can be used to overcome the limitations posed by the use of membranes alone. It is also a useful method for a patient not consenting for block graft for any medical reason.

Clinical Performance of Implant Overdenture Versus Fixed Detachable Prosthesis.

AIM: To evaluate the satisfaction of completely edentulous patients with a different number of implants to retain removable and support the fixed prosthesis. MATERIALS AND METHODS: Fifty patients with the single edentulous ridge (maxilla or mandible) were selected for this study and divided equally into five groups. Each group contained 10 patients. Group 1: conventional complete denture (negative control group), group 2: two implants retained overdenture, group 3: three implants retained overdenture, group 4: four implants retained overdenture, group 5: fixed detachable prosthesis with five implants placed between the mental foramen. After one year from completing the treatment, the patients were requested to fill a specially designed questionnaire to assess their overall quality of life and level of satisfaction, both estheti-cally and functionally. Comparison of data between groups was performed using the Chi-square tests. The level of statistical significance was considered at p < 0.05. RESULTS: Patients treated with conventional complete denture were all unsatisfied in their masticatory function, and 80% were also unsatisfied in phonetics, while only 50% of patients were satisfied aesthetically and mentally and 70% were satisfied in social life. The addition of two or more dental implants resulted in 100% satisfaction in the variables tested. There was no statistical difference between the number of implants and supra-structure design regarding patients' satisfaction. Furthermore, implants retained overdenture and fixed detachable prosthesis design scored the same satisfactory level. CONCLUSION: The satisfaction level of the conventional complete denture in the treatment of an edentulous arch can be dramatically improved by adding dental implants and changing the design to an overdenture. Two implants with an overdenture design is a valid treatment option for the edentulous arch as well as three and four implants. Fixed detachable prosthesis did not add any further patient satisfaction when compared to implant retained overdenture. CLINICAL SIGNIFICANCE: Two implants with overdenture to treat edentulous jaw is effective as five implant fixed prosthesis.