Murat Yenisey

Effect of Surgical Drill Guide on Heat Generated From Implant Drilling

PURPOSE The purpose of this study was to evaluate the heat generated in bone by 2 implant drill systems in vitro with and without using surgical drill guides. MATERIALS AND METHODS Temperature was measured with K type thermocouple in vitro using the bovine femoral cortical bone model. A constant drill load of 2.0 kg was applied throughout the drilling procedures via a drilling rig at a speed of 1,500 rpm. Two different implant drill systems-System A (with external irrigation) and System B (with both external and internal irrigation)-were evaluated. The samples were divided into 4 groups. System A test group 1 (TG1) included the following: 20 samples for drilling with surgical drill guides; control group 1 (CG1): 20 samples for classical implant site preparation. System B test group 2 (TG2) included the following: 20 samples for drilling with surgical drill guides; control group 2 (CG2): 20 samples for classical implant site preparation. Heat was measured at the final drill in the drilling sequence (4.2 and 4.4 mm). Thermocouples were placed at a 1-mm distance from the osteotomy area at depths of 3, 6, and 9 mm. Heat measurements were recorded out to 50 uses by a software program. Data were subjected to the Mann-Whitney U and Kruskal-Wallis tests. The alpha level was set a priori at 0.05. RESULTS The mean maximum temperatures at the depths of 3, 6, and 9 mm using surgical drill guides were 34.2 degrees , 39.7 degrees , and 39.8 degrees C, respectively, although without using surgical drill guides the values were 28.8 degrees , 30.7 degrees , and 31.1 degrees C. A statistically significant difference was found at the depths of 3, 6, and 9 mm between using surgical drill guides and classical drilling procedure. CONCLUSIONS From a heat generation standpoint, we conclude that preparing an implant site with using surgical drill guides generates heat more than classical implant site preparation regardless of the irrigation type.

Effects of chemical surface treatments of quartz and glass fiber posts on the retention of a composite resin

STATEMENT OF PROBLEM Failure of a fiber post and composite resin core often occurs at the junction between the 2 materials. This failure process requires better characterization. PURPOSE The purpose of this study was to evaluate the effect of 2 chemical solvents, hydrogen peroxide and methylene chloride, on the shear bond strength of quartz and glass fiber posts to a composite resin. MATERIAL AND METHODS Twenty-four posts (3 +/-0.1 mm in length) were prepared for each quartz (LIGHT-POST (LP)) and glass fiber (Cytec blanco (CB)) post. Posts were horizontally embedded in acrylic resin with half of the post diameter exposed. The exposed surfaces were successively ground with 400-, 800-, and 1200-grit silicon carbide papers, to ensure uniform smoothness. The specimens were divided into 3 subgroups (n=8) representing different surface treatment techniques, including application of silane for 60 seconds (S), etching with hydrogen peroxide for 20 minutes (H), and etching with methylene chloride for 5 seconds (M). Silane-treated specimens served as controls. A dual-polymerized composite resin (Tetric EvoCeram) was placed in a polytetrafluoroethylene mold (30 x 2 mm) positioned upon the post specimens and polymerized for 20 seconds with a light-emitting diode (LED) polymerization unit. The specimens were stored in water at 37 degrees C for 24 hours. Shear bond strength values (MPa) of posts and composite resin cores were measured using a universal testing machine with a crosshead speed of 0.5 mm/min. Data were analyzed by 2-way analysis of variance (ANOVA). Post hoc Tukey intervals for comparison among the 2 post materials and 3 surface treatment techniques were calculated (alpha =.05). The effect of the chemical surface treatments on glass and quartz fiber post surfaces were examined with a scanning electron microscope (SEM). RESULTS There were significant differences between the shear bond strength for LP and CB (P<.001). For all groups, the application of H showed the highest bond strength values. There was no significant difference between the S and M groups (P>.05). The SEM observations demonstrated that the fiber post surfaces were modified after chemical surface treatment techniques. CONCLUSIONS The surface treatment of quartz and glass fiber posts with hydrogen peroxide significantly enhanced the shear bond strength of the composite resin tested due to its ability to dissolve the epoxy resin matrix used in each post. The lowest bond strength was obtained with M and S groups. Application of methylene chloride to the fiber post surfaces for 5 seconds was not effective in increasing the shear bond strength of the fiber post to composite resin.

Comparison of Heat Generation During Implant Drilling Using Stainless Steel and Ceramic Drills

PURPOSE The purpose of this study was to compare the heat generated from implant drilling using stainless steel and ceramic drills. MATERIALS AND METHODS A total of 40 fresh bovine femoral cortical bone samples were used in this study. A constant drill load of 2.0 kg was applied throughout the drilling procedures via a drilling rig at a speed of 1,500 rpm. Two different implant drill types (stainless steel and ceramic) were evaluated. Heat was measured with type K thermocouple from 3 different depths. Data were subjected to the independent-sample t test and Pearson correlation analysis. The α level was set a priori at 0.05. RESULTS The mean maximum temperatures at the depths of 3 mm, 6 mm, and 9 mm with the stainless steel drill were 32.15°C, 35.94°C, and 37.05°C, respectively, and those with the ceramic drill were 34.49°C, 36.73°C, and 36.52°C, respectively. A statistically significant difference was found at the depth of 3 mm (P = .014) whereas there was no significant difference at the depths of 6 and 9 mm (P > .05) between stainless steel and ceramic drills. CONCLUSION Within the limitations of the study, although more heat was generated in the superficial part of the drilling cavity with the ceramic drill, heat modifications seemed not to be correlated with the drill type, whether stainless steel or ceramic, in the deep aspect of the cavity. Further clinical studies are required to determine the effect of drill type on heat generation.

Amelogenesis Imperfecta, hypoplastic type associated with some dental abnormalities: a case report

Amelogenesis imperfecta (AI) is a hereditary disorder expressing a group of conditions that cause developmental alterations in the structure of enamel. AI is a serious problem that reduces oral health-related quality of life and causes some physiological problems. The treatment of patients with AI may upgrade the quality of life and reinforce their self-esteem. Among the treatment options for AI, full-mouth metal reinforced porcelain restoration constitutes an important alternative because of its properties. This paper presents a case of AI of the hypoplastic rough type associated with a group of dental anomalies, and describes the prosthetic management of the patient. A 26-year-old female patient presented with a chief complaint of discolored teeth. Clinical and radiographic examination of the patient confirmed the diagnosis of rough pattern hypoplastic AI. The patient was treated with full-mouth metal reinforced porcelain fixed bridge. The adaptation of the temporomandibular joints and masticatory muscles was carefully observed periodically during 4 months and, after this period, the patient tolerated well her new vertical dimension. The patient received instructions on cleansing of the subpontic and interproximal areas. Follow-up visits were scheduled at 3 months and then at 6 months. No esthetic or functional problems were seen after the follow up period.

Effects of different surface pre-treatments on the bond strength of adhesive resin cement to quartz fiber post

Abstract Objective. The purpose of this study was to evaluate the effect of mechanical and chemical surface treatment methods on the bond strength of resin cement to fiber post. Materials and methods. The roots of 36 maxillary central incisor teeth were mounted in auto polymerized acrylic resin blocks (10 × 15 mm) and the root canals were enlarged with the drills of post system (2.1 mm width, 12 mm length). Thirty-six fiber posts were randomly assigned to one of the following surface conditioning methods: silane coupling agent, methylene chloride etching, 24% hydrogen peroxide etching, air abrasion with 50 µm Al2O3, 1–3 µm synthetic diamond particles and silica coating with 30 µm SiOx. Fiber posts were cemented to the root canals with adhesive resin cement (Panavia F 2.0). Three slices of 1.5 mm thick were obtained from each root. Push-out tests were performed with a universal testing machine. The data were analyzed with one-way analysis of variance (ANOVA) and Tukey HSD tests (α = 0.05). The effect of the surface treatments were examined under a scanning electron microscope (SEM) and surface roughness were evaluated with a profilometer. Results. Surface pre-treatment methods affected the bond strength (p < 0.05). The highest bond strengths were obtained by air abrasion with synthetic diamond particles, the lowest bond strength were obtained by etching with methylene chloride (p < 0.05). Conclusion. Mechanical surface pre-treatment methods showed higher bond strength values than chemical methods. Synthetic diamond particles may be an alternative method to increase resin cement bonding on the quartz fiber post surfaces.

Effect of surface treatments on the bond strength between resin cement and differently sintered zirconium-oxide ceramics

PURPOSE This study investigated the effects of surface treatments on bond strength between resin cement and differently sintered zirconium-oxide ceramics. METHODS 220 zirconium-oxide ceramic (Ceramill ZI) specimens were prepared, sintered in two different period (Short=Ss, Long=Ls) and divided into ten treatment groups as: GC, no treatment; GSil, silanized (ESPE-Sil); GSilPen, silane flame treatment (Silano-Pen); GSb, sandblasted; GSbSil, sandblasted+silanized; GSbCoSil, sandblasted+silica coated (CoJet)+silanized; GSbRoSil, sandblasted+silica coated (Rocatech-Plus)+silanized; GSbDSil, sandblasted+diamond particle abraded (Micron MDA)+silanized; GSbSilPen, sandblasted+silane flame treatment+silanized; GSbLSil, sandblasted+Er:Yag (Asclepion-MCL30) laser treated+silanized. The composite resin (Filtek Z-250) cylinders were cemented to the treated ceramic surfaces with a resin cement (Panavia F2.0). Shear bond strength test was performed after specimens were stored in water for 24h and thermo-cycled for 6000 cycles (5-55 °C). Data were statistically analyzed with two-way analysis of variance (ANOVA) and Tamhanes multiple comparison test (α=0.05). RESULTS According to the ANOVA, sintering time, surface treatments and their interaction were statistically significant (p<0.05). The highest bond strengths were obtained in GSbCoSil (Ss=13.36/Ls=11.19MPa) and lowest values were obtained in GC (Ss=4.70/Ls=4.62 MPa) for both sinter groups. CONCLUSIONS Sintering time may be effective on the bond strength and 30 μm silica coating (Cojet) with silane coupling application technique increased the bond strength between resin cement and differently sintered zirconium-oxide ceramics.

Prosthetic treatment of congenital hard and soft palate defects.

Obturator prostheses are used to improve mastication, speech, and swallowing by reestablishing oronasal separation and aesthetics in maxillary defect patients. A sectional and magnetically retained functional removable speech bulb prosthesis was planned to treat the congenitally cleft hard and soft palates of this patient. The obturator part, localized into lateral nasal undercuts covered with sound mucosa, was used to retain the complete denture. Two pieces of the prosthesis were joined together by a magnet in the mouth. A special hinge mechanism was added to join the complete denture and functional velopharyngeal parts of the prosthesis for the treatment of velopharyngeal inadequacy. Sufficient retention was obtained, and no major complications were seen in the patients prosthesis in periodic controls.

Effect of electrical discharge machining on dental Y-TZP ceramic-resin bonding.

PURPOSE The study determined (i) the effects of electrical discharge machining (EDM) on the shear-bond strength (SBS) of the bond between luting resin and zirconia ceramic and (ii) zirconia ceramics flexural strength with the three-point bending (TPB) test. METHODS Sixty 4.8mm×4.8mm×3.2mm zirconia specimens were fabricated and divided into four groups (n=15): SBG: sandblasted+silane, TSCG: tribochemical silica coated+silane, LTG: Er:YAG laser treated+silane, EDMG: EDM+silane. The specimens were then bonded to a composite block with a dual-cure resin cement and thermal cycled (6000 times) prior to SBS testing. The SBS tests were performed in a universal testing machine. The SBS values were statistically analyzed using ANOVA and Tukeys test. To determine flexural strength, sixty zirconia specimens were prepared and assigned to the same groups (n=15) mentioned earlier. After surface treatment TPB tests were performed in a universal testing machine (ISO 6872). The flexural strength values were statistically analyzed using ANOVA and Tukeys test (α=0.05). RESULTS The bond strengths for the four test groups (mean±SD; MPa) were as follows: SBG (Control), 12.73±3.41, TSCG, 14.99±3.14, LTG, 7.93±2.07, EDMG, 17.05±2.71. The bond strength of the EDMG was significantly higher than those of the SBG and LTG (p<0.01). The average flexural strength values for the groups SBG (Control), TSCG, LTG and EDMG were 809.47, 800.47, 679.19 and 695.71MPa, respectively (p>0.05). CONCLUSIONS The EDM process improved the SBS. In addition, there was no significant adverse effect of EDM on the flexural strength of zirconia.