Analysis of Satisfaction Levels in Completely Edentulous Patients Treated with Different Configurations of Implant Supported Rosthesis.

PURPOSE: The aim of this study is to evaluate and compare patient satisfaction levels in edentulous patients treated with different configurations of implant supported prosthesis. Also, the effect of previous prosthesis experience before implant treatment on patient satisfaction was investigated. MATERIALS AND METHODS: A study population of 142 patients was identified. Patients seperated into four treatment types. Group 1 comprised 43 patients treated with implant supported overdenture for mandible and conventional complete denture for maxilla while group 2 comprised 32 patients treated with implant supported overdentures for maxilla and mandible. Group 3 comprised 26 patients treated implant supported overdenture for mandible and fixed prosthesis for maxilla. Group 4 comprised 41 patients treated with implant supported maxillomandibular fixed restorations. A questionnaire consisting of specific issues about masticatory performance, pronunciation, comfort, social ability were used to evaluate treatment outcomes. RESULTS: The patients in group 4 were significantly more satisfied regarding masticatory performance than other treatment modalities. VAS scores of Group 3 and group 4 regarding comfort and social ability were similar while scores of these two groups were significantly higher than that of group 1 and 2. The patients who used conventional removable prosthesis before implant treatment were more satisfied with their implant supported prosthesis regarding social ability.(p=.03) Conclusion: It was found that treatment design of that implant supported fixed prosthesis on maxilla and implant overdenture on mandible provided comparable level of satisfaction with maxillomandibular fixed prosthesis for edentulous patients. Implant supported fixed prosthesis for maxilla and implant supported overdenture for mandible served as a practical alternative to satisfy patients especially in patients with mandibular atrophy who would demand extensive surgeries for maxillomandibular fixed prosthesis. Satisfaction level of implant supported overdenture was not superior to conventional prosthesis for maxilla. Previous removable prosthesis experience may influence social comfort of patients.

Is Incisive Papilla a Good Landmark to Predict Clinical Outcomes and the Esthetic Perceptions of Edentulous Patients Treated with Implant-Supported Fixed Prostheses on Maxillae?

Purpose: To investigate the effect of incisive papilla on esthetic ratings and lip support for patients who are treated with implant-supported fixed prostheses on edentulous maxillae. Materials and Methods: A study population of 118 patients with maxillomandibular edentulism was identified. A self-administered questionnaire was used to evaluate treatment outcomes through a patient perspective. Also, clinical factors such as smile line, maxillary resorption, incisive papilla position, and lip support were evaluated. Results: Lip support has a significant effect on the facial esthetic scores of patients, while smile line and incisive papilla localization have not had a proven statistically significant effect on esthetic and facial esthestic scores of patients treated with implant-supported fixed prostheses on maxillae. Conclusion: Although the patients were diagnosed with disadvantageous clinical factors such as crestally localized incisive papilla, they still noted higher esthetic scores with their fixed prostheses. Factors that affect the esthetic perception of patients or their priorities should be investigated more to understand the reasons for patient satisfaction with prostheses.

Effect of surface treatment and luting agent type on shear bond strength of titanium to ceramic materials.

PURPOSE: This study aimed to compare the effect of different surface treatments and luting agent types on the shear bond strength of two ceramics to commercially pure titanium (Cp Ti). MATERIALS AND METHODS: A total of 160 Cp Ti specimens were divided into 4 subgroups (n = 40) according to surface treatments received (control, 50 µm airborne-particle abrasion, 110 µm airborne-particle abrasion, and tribochemical coating). The cementation surfaces of titanium and all-ceramic specimens were treated with a universal primer. Two cubic all-ceramic discs (lithium disilicate ceramic (LDC) and zirconia-reinforced lithium silicate ceramic (ZLC)) were cemented to titanium using two types of resin-based luting agents: self-cure and dual-cure (n = 10). After cementation, all specimens were subjected to 5000 cycles of thermal aging. A shear bond strength (SBS) test was conducted, and the failure mode was determined using a scanning electron microscope. Data were analyzed using three-way ANOVA, and the Tukey-HSD test was used for post hoc comparisons (P < .05). RESULTS: Significant differences were found among the groups based on surface treatment, resin-based luting agent, and ceramic type (P < .05). Among the surface treatments, 50 µm air-abrasion showed the highest SBS, while the control group showed the lowest. SBS was higher for dual-cure resin-based luting agent than self-cure luting agent. ZLC showed better SBS values than LDC. CONCLUSION: The cementation of ZLC with dual-cure resin-based luting agent showed better bonding effectiveness to commercially pure titanium treated with 50 µm airborne-particle abrasion.

Inhibition of cathepsin-K and matrix metalloproteinase by photodynamic therapy.

OBJECTIVES: The objective of this study was to determine the effects of antimicrobial photodynamic therapy (aPDT) with indocyanine green (ICG) and toluidine blue (TB) on protease activity (matrix-bound cathepsin K and matrix metalloproteinase (MMP) and dentin bond strength. METHODS: Caries-free human third molars were assigned to five groups: 1-control group, 2-application of ICG with activation using an 810 nm diode (aPDT), 3-application of ICG, 4-application of TB with activation using a 660 nm diode (aPDT), and 5-application of TB. For the enzymatic investigation, dentin beams were incubated for either 3 days or 3 weeks. Aliquots of the incubation media were analyzed by ELISA for CTX (C-terminal cross-linked telopeptide of type I Collagen) and ICTP (cross-linked carboxy-terminal telopeptide of type I collagen). For microtensile bond strength testing (µTBS), composite resins were layered onto the tooth surface; the samples were then subjected to µTBS. Kruskall-Wallis and Mann-Whitney U tests were applied for statistical analysis of CTX and ICTP, one way-ANOVA and Tukey's test were applied for statistical analysis of µTBS. RESULTS: Pretreating the dentin matrices with aPDT decreased the endogenous protease activity. ICG with laser activation resulted in the highest µTBS. Therefore, aPDT should be considered as a treatment method because it can reduce MMP-mediated dentin degradation and increase the µTBS. SIGNIFICANCE: Inhibiting endogenous protease activity improves the stability of the dentin-adhesive bond and the durability of the bond strength.

Stability of dental implants with sandblasted and acid-etched (SLA) and modified (SLActive) surfaces during the osseointegration period.

Background. The surface properties of implants are effective factors for increasing the osseointegration and activity of osteoprogenitor cells. This study compared the stability of dental implants with sandblasted and acid-etched (SLA) and modified surfaces (SLActive) using the resonance frequency analysis (RFA). Methods. In a split-mouth design, 50 dental implants with either SLA surface properties (n=25) or modified (SLActive) surface properties (n=25) were placed in the mandibles of 12 patients with a bilateral posterior edentulous area. Implant stability was measured using RFA (Osstell) at implant placement time and every week for 1, 2, and 3 months before the conventional loading time. Results. One week following the implantation, implant stability increased from 70 to 77.67 for SLA and from 71.67 to 79 for SLActive (P < 0.05). Stability improved each week except in the 4th week in SLActive surface measurements. No significant differences were observed between the groups at 2 and 3 months (P > 0.05). Conclusions. For both implant surfaces, increased stability was observed over time, with no significant differences between the groups.

Effect of mucosa thicknesses on stress distribution of implant-supported overdentures under unilateral loading: Photoelastic analysis.

INTRODUCTION: The aim of this study was to evaluate the effect of different heights of attachment and mucosa thicknesses on the stress distribution of two implant-retained mandibular overdenture designs under loading using the photoelastic stress analysis method. MATERIALS AND METHODS: Six photoelastic models of an edentulous mandibula were fabricated with two solitary implants that were placed in the canine regions. The attachment systems studied were ball and locator stud attachments. Both the ball and locator groups included three models that had different residual ridge heights so as to provide different mucosa thicknesses (1 mm-1 mm, 1 mm-2 mm, 1 mm-4 mm). A static vertical force of 135 N was applied unilaterally (each on the right then the left side) to the central fossa of the first molars. Models were positioned in the field of a circular polariscope to observe the distribution of isochromatic fringes around the implants and the interimplant areas under loading. The photoelastic stress fringes were monitored and recorded photographically. RESULTS: The ball attachment groups showed higher stress values than did the locator groups under loading. Both attachment systems produced the lowest stress values in stimulated 1 mm-1 mm mucosa thickness models. The models with 1 mm-2 mm mucosa thicknesses showed higher stress values than did other models for both attachment systems. The highest stress value observed around both attachment systems was the moderate level in all test models. CONCLUSION: In different height mucosa thicknesses, locator attachment models distributed the load to the other side of the implant and its surrounding tissue, whereas the ball attachment did not. Regardless of mucosal thickness and attachment type, the implant on the loading side was subjected to the highest stress concentration.

Effect of gallic acid addition on some mechanical properties of self-adhesive resin cements.

Self-adhesive resin cements (RCs) activate matrix metalloproteinase (MMP) and cathepsin-related collagen degradation, and gallic acid (GA) inhibits the activity of both MMPs and cysteine cathepsins. The purpose of this study was to evaluate the setting time, biaxial flexural strength, and Vickers hardness of self-adhesive RCs after the addition of two different concentrations of GA. RelyX U200 (3M ESPE) and Panavia SA (Kuraray) were modified with 0.5 and 1 wt% GA. The setting time of five samples in each RC group was assessed using a thermocouple apparatus as described in the ISO 4049 test. Biaxial flexure strength was measured using a universal testing machine until failure. Vickers hardness was measured with three randomized indentations on the surface of each resin disc. RCs without GA were used as control. Data were analyzed using a one-way analysis of variance and Tukey's HSD test (α = 0.05). The setting times ranged from 2.4 to 4.6 min for RelyX and from 4.9 to 6.0 min for Panavia. The biaxial flexure strength ranged from 76.5 to 109.7 MPa for RelyX and from 73.3 to 108.2 MPa for Panavia. Vickers hardness values ranged from 41.6 to 58.6 for RelyX and 27.2 to 33.6 for Panavia. The addition of 0.5 and 1 wt% GA to improve durability of resin-dentin bonds had no adverse effects on setting time, whereas the biaxial flexure strength and Vickers hardness values for the tested materials were significantly reduced.

Effect of Combined Surface Treatments on Surface Roughness and Resin Bond Strength to Y-TZP Ceramic and Nickel-Chromium Metal Alloy.

Objective: This study compared the effects of different surface treatments on the surface roughness (Ra), and shear bond strength (SBS) of resin cement to yttria-stabilized tetragonal zirconia (Y-TZP) ceramic and nickel-chromium (Ni-Cr) base metal alloy, respectively. Materials and methods: Thirty disk-shaped specimens (3 mm height and 10 mm diameter) of each material (Y-TZP and Ni-Cr) were prepared. Both zirconia and metal specimens were randomly assigned to three equal groups, according to the surface treatments (n = 10): sandblasting, sandblasting + Er:YAG laser, and sandblasting + Nd:YAG laser. Resin cement cylinders (4 mm diameter and 3 mm thickness) were placed on each specimen. The SBS tests were performed at a 1 mm per minute crosshead speed through a knife-edge rod after 5000 thermal cycles. The Ra (µm) of the specimens was measured using a profilometer and evaluated topographically by atomic force microscopy and scanning electron microscopy. Analysis of variance, followed by Tukey's honestly significant difference, in addition to the Kruskal-Wallis test, followed by the Mann-Whitney U test, were used for statistical analysis (α = 0.05). Results: Combined sandblasting and laser treatment of the metal groups led to statistically higher Ra values than sandblasting alone (p < 0.05). For Y-TZP, there were no significant differences between the Ra values of the subgroups (p > 0.05). The SBS of the sandblasted metal group was significantly higher than the other two laser-irradiated groups, whereas the SBS of sandblasted zirconia was only significantly higher than the Nd:YAG laser-irradiated group (p < 0.05). Conclusions: Combined laser and sandblasting surface treatments resulted in rougher surfaces than sandblasting alone, especially for the metal specimens. Sandblasting, alone, improved the SBS of resin cement in both metal and zirconia, compared with the laser and sandblasting treatments, combined.

Effect of gallic acid addition on some mechanical properties of self-adhesive resin cements

Abstract Self-adhesive resin cements (RCs) activate matrix metalloproteinase (MMP) and cathepsin-related collagen degradation, and gallic acid (GA) inhibits the activity of both MMPs and cysteine cathepsins. The purpose of this study was to evaluate the setting time, biaxial flexural strength, and Vickers hardness of self-adhesive RCs after the addition of two different concentrations of GA. RelyX U200 (3M ESPE) and Panavia SA (Kuraray) were modified with 0.5 and 1 wt% GA. The setting time of five samples in each RC group was assessed using a thermocouple apparatus as described in the ISO 4049 test. Biaxial flexure strength was measured using a universal testing machine until failure. Vickers hardness was measured with three randomized indentations on the surface of each resin disc. RCs without GA were used as control. Data were analyzed using a one-way analysis of variance and Tukey's HSD test (α = 0.05). The setting times ranged from 2.4 to 4.6 min for RelyX and from 4.9 to 6.0 min for Panavia. The biaxial flexure strength ranged from 76.5 to 109.7 MPa for RelyX and from 73.3 to 108.2 MPa for Panavia. Vickers hardness values ranged from 41.6 to 58.6 for RelyX and 27.2 to 33.6 for Panavia. The addition of 0.5 and 1 wt% GA to improve durability of resin-dentin bonds had no adverse effects on setting time, whereas the biaxial flexure strength and Vickers hardness values for the tested materials were significantly reduced.

Evaluation of C. Albicans and S. Mutans adherence on different provisional crown materials.

PURPOSE: Bacterial adhesion on provisional crown materials retained for a long time can influence the duration for which permanent prosthetic restorations can be healthily worn in the oral cavity. The aim of this study was to compare seven different commonly used provisional crown materials with regard to Streptococcus mutans and Candida albicans surface adhesion. MATERIALS AND METHODS: For each group, twenty specimens of the provisional fixed prosthodontic materials TemDent (Schütz), Imident (Imicryl), Tab 2000 (Kerr), Structur Premium (Voco), Systemp (Ivoclar Vivadent), Acrytemp (Zhermack), and Takilon-BBF (Takilon) were prepared (diameter, 10.0 mm; height, 2.0 mm). Surface roughness was assessed by atomic force microscopy. Each group was then divided into 2 subgroups (n=10) according to the microbial suspensions used: S. mutans and C. albicans. The specimens were incubated at 37℃ with S. mutans or C. albicans for seven days. Bacterial adherence on surfaces was assessed using the 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) assay. RESULTS: S. mutans showed maximum adhesion to Structur, followed by Systemp, Acrytemp, Takilon, Tab 2000, Imident, and TemDent (P<.05). The highest vital C. albicans adhesion was noted on Takilon, followed by Imident and Tab 2000; the lowest adhesion was noted on Systemp (P<.05). CONCLUSION: The materials showed significant differences in the degree of bacterial adhesion. C. albicans showed higher surface adhesion than S. mutans on provisional crown and fixed partial denture denture materials.

Management of restricted mouth opening caused by radiation: A clinical report.

Trismus, a commonly observed sequela in patients who have undergone radiation therapy to treat malignancies of the head and neck, causes a loss of function that reduces patients' overall quality of life. Radiation can cause intense fibrosis in the masticatory muscles, and this fibrosis may lead to trismus. This clinical report describes the management of a patient with radiation-induced trismus who was treated with a custom-made mouth-opening device. The device had maxillary and mandibular sections, was made of a thermoactive acrylic resin material, and was connected with 2 vertical screws in the right and left canine regions. The screws were adjusted daily to increase the oral opening, such that each turn of the screws increased the opening by 0.25 mm. With the help of this device, at the end of a 4-month follow-up period, the patient's maximal interdental distance had increased from 7.16 mm to 19.50 mm. The intraoral opening device described in this study is useful for achieving a vertical opening sufficient to perform dental treatment.

Fabrication of a screw-retained hybrid prosthesis following treatment of peri-implant defects: a case report.

The etiology of marginal bone loss around osseointegrated implants is primarily based on the biomechanical and/or microbial factors. If stresses and strains around dental implants under functional loading conditions are expected to exceed the physiologic tolerance thresholds of the alveolar bone, the fixed hybrid prosthesis might be a more reliable treatment of choice instead of fixed metal ceramic restorations. The purpose of this article is to report the 1-year follow-up of the periodontal and prosthetic rehabilitation of a patient who has presented with symptoms of peri-implantitis due to incorrectly planned implant supported fixed metal ceramic bridge which was later replaced with screw-retained hybrid prosthesis following the treatment of peri-implant defects. Treatment helped to maintain patient's self-confidence and comfort, as well as favorable masticatory function. Rehabilitation with screw retained hybrid prosthesis is an ideal treatment of choice for maxillomandibular skeletal discrepancies.