Ibrahim Tulunoglu

Resin shear bond strength to porcelain and a base metal alloy using two polymerization schemes

STATEMENT OF PROBLEM Fractures in ceramometal restorations can occur and need to be repaired because replacements are not an economic solution. PURPOSE This study evaluated the shear bond strengths of 4 porcelain repair systems (Metabond C&B [ME], Silistor [SI], Clearfil Lustre [CL], and Scotchbond Multipurpose Plus [SQ]) to a base metal alloy and porcelain in relation with the polymerization shrinkage of a visible light-cured composite superstructure and compared with the ceramometal bond strength (Vita VMK 68). MATERIAL AND METHODS Thirty-two samples were prepared for each bonding system: 16 for resin-metal bond strength test, and 16 for resin-porcelain bond strength test. For each group, bonding agent was applied to 8 substructures and the resin superstructure was polymerized onto the bonding agent; and for the remaining 8 specimens, prepolymerized resin superstructures were bonded with bonding agent. All specimens were subjected to 500 cycles between 5 degrees C and 55 degrees C with 20 seconds dwell time. Tests were performed in a mechanical testing machine with a 0.5 mm/min crosshead speed. RESULTS All materials showed an increase in shear bond strength when prepolymerized resin superstructures were used. However, the effect of polymerization shrinkage of resin superstructure was statistically significant only for CL group (P <. 05). The highest metal-resin bond was obtained from ME group with prepolymerized resin superstructures (35.27 +/- 2.40 MPa), and the lowest value was obtained for the SI group in which resin superstructures were polymerized in situ (8.71 +/- 1.03 MPa). The highest porcelain-resin bond was obtained from SC group with prepolymerized resin superstructures (20.71 +/- 1.13 MPa) and the lowest was obtained from SI group (9.99 +/- 1.52 MPa). CONCLUSION Higher bond strength values were obtained with prepolymerized resin superstructures compared to in situ polymerized superstructures. Metabond C&B provided the best results for both prepolymerized and in situ polymerized resin superstructure preparation techniques at the failures where metal was exposed. The best results in situations in which the fracture is limited into porcelain were obtained with the use of Scotchbond Multipurpose Plus material. However, a variety of in vivo and in vitro tests are required before a final judgment is made.

Which device is more accurate to determine the stability/mobility of dental implants? A human cadaver study

Non-invasive devices including resonance frequency (RF) analysis and mobility measuring (MM) damping capacity assessment are used to measure implant stability/mobility. The aims of the study were to compare the primary stability of implant inserted into extraction sockets by using RF with cable, RF wireless and new wireless MM device, to clarify the relation between these devices and to understand the correlations between peri-implant bone levels and implant stability. A total of 30 screw-type implants (3.75 x 11 and 4.2 x 11 mm) were inserted into extraction sockets of eight mandibular pre-molar regions of human cadavers. The primary stability of implants was measured by three devices after insertion. Peri-implant vertical defects were created in millimetre increments ranging between 0 and 5 mm, and stability/mobility of implants were analysed. At placement, the mean implant stability quotient of RF with cable, RF wireless and MM device values was 46 +/- 1, 57.8 +/- 9 and -5.4 +/- 1, respectively. Statistical correlations were demonstrated between these devices (P = 0.001). Statistically significant differences were presented for all peri-implant detects ranging between 0 and 5 mm for RF with cable and RF wireless at all increments. However, only a significant decrease was found between 0 and 1 mm defects, and 4 and 5 mm defects in MM device. Although RF with cable and RF wireless seem to be suitable to detect peri-implant bone loss around implants in 1 mm increments, the new MM device may not be suitable to detect the 1 mm peri-implant bone changes in human dried cadaver mandibles.

Evaluation of articulation of Turkish phonemes after removable partial denture application

In this study, the adaptation of patients to removable partial dentures was evaluated related to articulation of Turkish phonemes. Articulation of /t,d.n,l,r/, /g,k/, /b,p,m/ and /s,z,ş,v,f,y,j,h,c/ phonemes were evaluated by three speech pathologists, on records taken from 15 patients before the insertion of a removable partial denture, just after insertion, and one week later. The test consisted of evaluation of phoneme articulation of independent syllables in terms of distortion, omission, substitution, mass effect, hypernasality and hyponasality. Data were evaluated with Cochrane Q. McNemar and Kruskal-Wallis tests. The results showed that for some phonemes, problems in articulation occurred after the insertion of a removable partial denture while for others a significant amelioration was observed after the insertion of a removable partial denture. In general, problems in articulation of evaluated phonemes were resolved after one week of use.

The influence of platform switching on clinical, laboratory, and image-based measures: a prospective clinical study.

PURPOSE This prospective study was conducted to compare the marginal bone level alterations, stability/mobility measurements, and volume of myeloperoxidase (MPO) and nitric oxide (NO) of peri-implant sulcus fluid (PISF) between platform-switched (PS) and standard platform (SP) implants inserted to mandibular premolar/molar regions with a single-stage protocol. MATERIALS AND METHODS Thirty-two (16 PS and 16 SP) implants restorated with fixed prosthesis were included in the study. For both implant systems standard implant dimensions were used. Implant abutment connections and final restorations were made after 3 months of osseointegration. Standard parallel periapical radiographs were used to measure marginal bone loss in over time. Resonance frequency analysis (RFA) and mobility measuring (MM) device were used to determine implant stability/mobility. PISF samples were derived with paper strips and PISF MPO and nitrite level analysis were done spectrophotometrically. Peri-implant parameters were assessed by periodontal indices and all parameters were evaluated at baseline, 1, 3, 6, and 12 months follow-up. RESULTS No healing problems were recorded for all implants at the end of the study period. At 12 months, mean bone loss measures were 0.84 and 0.76 mm, and mean implant stability quotient (ISQ) values were 74.04 and 76 for PS and SP implants, respectively. Mean MM values were found as -4.82 for PS and -6.26 for SP implants. There were no significant differences between implant types according to PISF volume and laboratory biochemical measures including MPO and NO, and clinical peri- implant indices at any time point. CONCLUSION Platform switching seems not to affect the marginal bone level, clinical peri-implant parameters and MPO and NO metabolism around implants inserted to mandibular premolar/molar regions when using a single-stage protocol.

A Critically Appraised Topic Review of Computer-Aided Design/Computer-Aided Machining of Removable Partial Denture Frameworks

A critically appraised topic (CAT) review is presented about the use of computer-aided design (CAD)/computer-aided machining (CAM) removable partial denture (RPD) frameworks. A systematic search of the literature supporting CAD/CAM RPD systems revealed no randomized clinical trials, hence the CAT review was performed. A PubMed search yielded 9 articles meeting the inclusion criteria. Each article was characterized by study design and level of evidence. No clinical outcomes research has been published on the use of CAD/CAM RPDs. Low levels of evidence were found in the available literature. Clinical research studies are needed to determine the efficacy of this treatment modality.

Iliac crest flap for mandibular reconstruction after advanced stage mandibular ameloblastoma resection.

Abstract Ablative surgeries for neoplastic processes of the oral cavity, traumas, infections/inflammations, osteoradionecrosis, and congenital deformities are the most common causes of large mandibular defects. Ameloblastoma is a locally aggressive tumor that, if not treated, can gain an enormous size and cause severe facial disfigurement and functional impairment. Although the smaller lesions of ameloblastoma in the mandible are treated by conservative approaches such as marsupialization, enucleation, and curettage combined with liquid nitrogen spray cryosurgery, larger lesions require radical surgical ablation procedures resulting in large tissue defects. A large mandibular defect has deleterious effects on a person’s life, with a significant loss in the quality of life unless it is reconstructed successfully. The aim of present case series report is to show the results of the multidisciplinary treatment of patients with advanced stage ameloblastoma, including tumor resection, simultaneous reconstruction with iliac crest flap, followed by placement of endosseous dental implants, and finally the prosthodontic rehabilitation.

Primary stability/mobility of 1-stage and 2-stage dental implants: a comparative in vitro study.

Purpose:To evaluate the primary stability of 1-stage (nonsubmerged) and 2-stage (submerged) implants via newest wireless resonance frequency (RF) analyzer and newer wireless mobility measuring (MM) device. Materials and Methods:Six 1-stage dental implants with internal hex connection and six 2-stage dental implants, 4.1 mm in diameter and 11.5 mm in length, were inserted bilaterally into the first premolar, second premolar, and first molar regions of 6 standard mandibular transparent self-curing acrylic resin models. After that, the periimplant circular bone defects were created in millimeter increments ranging between 0 and 5 mm to the same extent on all implants. Results:Implant stability quotient values significantly decreased at 1-stage and 2-stage implants when periimplant defects increased. Similar implant stability quotient values were found for both implant types; however, significantly lower MM values were noted for 2-stage implants. Irrespective of implant systems, the results indicated a significant association between wireless RF analyzer and wireless MM device. Conclusion:Both wireless RF analyzer and wireless MM device were adequate in assessing implant stability. There was no difference between 2-stage and 1-stage implant systems, except lower MM values were noted for nonsubmerged implants.

Implant Stability and Peri-Implant Parameters in Free Vascularized Iliac Graft Transplantation Patients: Report of Three Ameloblastoma Cases

BACKGROUND Ameloblastoma, a benign but locally aggressive tumor, accounts for 9% to 11% of all odontogenic tumors. Radical procedures, including resection, are performed. To restore functions after resection, free vascularized iliac grafts followed by a dental implant-supported prosthesis are used as a successful treatment option. The aim of this case report is to evaluate the peri-implant clinical status and stability of dental implants placed in patients with advanced-stage mandibular ameloblastomas. METHODS Examinations of three patients revealed extensive ameloblastomas, and hemimandibulectomies were performed. Six months after surgeries, two to four dental implants were placed. After 6 months of healing, one fixed prosthesis and two removable prostheses were delivered. The stability of implants was evaluated at the surgical baseline and 1, 3, 6, 9, and 12 months after surgery by resonance-frequency (RF) analysis. Peri-implant clinical parameters (i.e., plaque index [PI], gingival index [GI], gingival bleeding time index [GBTI], and peri-implant probing depth [PD]) were recorded at the delivery of the prosthesis and at follow-ups at 1, 3, and 6 months. RESULTS Nine implants that supported one removable prosthesis and two fixed prostheses were placed. RF analysis revealed no significant changes in implant stability during 12 months of follow-up. Peri-implant clinical parameters (PI, GI, and GBTI) showed slight improvements during follow-up. Although advancements were observed in 6 months, PDs were found to be deeper than optimal measurements for the whole observation time. CONCLUSION The implant-supported prosthetic rehabilitation of patients with ameloblastomas reconstructed with free vascularized iliac crest grafts can be a predictive alternative for improving the quality of life of patients in which a high implant stability and acceptable peri-implant health may be achieved.

Interdisciplinary treatment of an adult patient with old extraction sites.

This case report describes the interdisciplinary treatment of a 31-year-old female patient showing a protrusive profile, maxillary constriction, mandibular crowding, a Class III canine relationship complicated with multiple missing teeth, old atrophic extraction sites, and periodontal defects. The lower dental arch irregularity was eliminated by air-rotor stripping (ARS). The upper extraction site was opened for prosthetic rehabilitation, whereas closure of the lower extraction space was preferred. The narrow alveolar crest of the atrophic bone was augmented with the use of autogenous bone, beta-tricalcium phosphate (Cerasorb), and autogenous platelet-rich plasma. A functional and esthetic occlusion in an improved facial profile was established at the end of orthodontic treatment combined with ARS technique, surgery, and prosthodontics.

Penetration of radiocalcium at the margins of resin and glass ionomer dentine bonding agents in primary and permanent teeth

OBJECTIVES The purpose of this study was to compare the leakage of three resin dentine bonding agents (Prime and Bond, Scotchbond Multi-Purpose, Probond) and a glass ionomer dentine bonding agent (GC Fujibond LC), in cervical cavities prepared in primary and permanent molar teeth restored with a hybrid composite resin (Tetric). METHODS Cervical cavities without a bevel at the cavo-surface margins were prepared in the buccal and lingual surfaces of extracted primary and permanent molar teeth. After being restored, the teeth were stored for 1 week in a saline solution at 37 degrees C and then thermally cycled between 5 and 55 degrees C. Marginal leakage was determined subsequently using a radioactive isotope containing 45Ca and an autoradiographic technique. RESULTS The results revealed that there were no statistically significant differences in microleakage of the bond between permanent and primary teeth dentine and Fuji Bond LC and Probond dentine bonding agents. The difference between permanent and primary teeth groups for gingival values of the Prime and Bond 2.1 group U=22.5, p=0.0355 and the Scotchbond Multipurpose group U=24.0, p=0.0406 were statistically significant. There were no significant differences between the occlusal and gingival microleakage values in either primary or permanent teeth with Prime and Bond 2.1, Fuji Bond LC and Probond except the difference at Scotchbond Multipurpose in primary teeth. For primary teeth gingival margins, none of the bonding systems were significantly different from the control group. CONCLUSIONS These results indicate that although no statistically significant differences were found between test and control group values, the use of Fuji II LC in cervical cavities with cementum margins in primary teeth would provide the best resistance to microleakage among the test materials while the use of Scotchbond Multi-Purpose would provide the best resistance to microleakage in cervical cavities with cementum margins in permanent teeth.