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PURPOSE Despite the high success rate of implant-supported fixed restorations in dentistry, there is a lack of evidence on the marginal seal for dental cement. Thus, this study aimed to evaluate the marginal seal of implant-supported crowns and partial dentures cemented using four different dental cements. MATERIALS AND METHODS The study evaluated the marginal seal of implant-supported crowns and partial dentures cemented using zinc phosphate, resin-modified glass-ionomer, self-adhesive resin, and noneugenol, acrylic-urethane polymer-based temporary dental cements. After cementation and thermal cycling procedures, the samples were incubated in Escherichia coli suspension for 5 days at 37°C under an aerobic environment. After debonding the restorations under sterile conditions, sterile cotton swabs were used to obtain microbial samples from the inner surface of each restoration and abutment surface. To analyze the contamination, each sample was immersed in a brain-heart infusion culture medium and incubated at 37°C for 24 hours, and then, the colony-forming units were counted and recorded. RESULTS Regarding the number of colonies for Escherichia coli, the results revealed no substantial difference between the crowns and the fixed partial restorations (P = .25). However, the differences in the level of contamination between the cement groups were significant (P ≤ .001). The self-adhesive resin cement samples showed the lowest level of contamination, followed by the zinc phosphate and resin-modified glass-ionomer cements. The difference in the level of contamination between these groups was not significant. The temporary cement group exhibited significantly higher numbers of bacterial colonies in comparison to the other cement groups. CONCLUSION Self-adhesive resin cement has better biologic properties for retaining implant-supported restorations than other types of dental cement.

BACKGROUND In edentulous patients, the concept of 4 implants with early loading has been widely used in clinical settings. In the case of bone atrophy in the anterior maxilla, using short implants or an angulated implant may be a good choice for treatment. The occlusal scheme remains a key aspect of All-on-4. The aim of this study was to use the 3-dimensional (3D) finite element method (FEM) to evaluate how different All-on-4 designs for canine-guided and group function occlusion affected the distribution of stress in the atrophic premaxilla. MATERIAL AND METHODS A 3D edentulous maxilla model was created and in 3D FEM, 3 different configurations - M4, All-on-4, and short implant - were modeled by changing the anterior implants and using 2 different occlusal schemes. For each model, the occlusal load was applied to simulate lateral movements. For cortical bone, the maximum and minimum principal stress values were generated, and for ductile materials, von Mises stress values were obtained. RESULTS No significant differences were detected among the models; generally, however, the highest stress values were observed in the M-4 model and the models with short implants. Slightly higher stress values were observed in the group function occlusion group than in the canine-guided occlusion group. CONCLUSIONS To promote better primary stabilization, M-4 or short implant configurations with canine-guided occlusion appear to be preferable for patients who have severe atrophy in the anterior maxilla.

Background Despite the wide use of implants in dentistry, there is insufficient information about the ideal cement for retention. Purpose To determine the cement bond strength and marginal leakage of crown and partial denture cemented to implant abutments by four different types of cement. Materials and methods Eighty-four direct abutments were divided into eight groups (n = 7). Fifty-six crown and bridge restorations were cemented using zinc phosphate (ZM), temporary cement (TM), resin-modified glass-ionomer cement (GM), and self-adhesive resin cement (RM). After cementation, thermal cycling and incubation in basic fuchsin dye was applied. The maximum load to failure, marginal leakage, and fracture modes were evaluated. Results The mean of retention strength for the bridges (874 N) was higher than the crown samples (705 N) (P = .005). The mean of retention strength for each cement group was ZM = 1298, RM = 1027, GM = 646, and TM = 187 N (P ≤ .0001). Marginal leakage was recorded in majority of the samples; the highest incidence was detected for ZM samples. The cement fracture was mostly adhesive in nature. Conclusion Self-adhesive resin and resin-modified glass ionomer cement had better mechanical properties to retain implant supported restorations.

The aim of this study was to determine the effect of restoration design on the fracture resistance of different computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics and investigate the marginal leakage of endocrowns according to different types of cement. In total, 96 extracted mandibular first premolars were used for fabrication of endocrowns, 48 of the endocrowns were divided into 6 groups (n = 8) according to intracoronal cavity depth (2 and 3 mm) and CAD/CAM ceramics (lithium disilicate IPS e.max-CAD, zirconia-reinforced glass-ceramic Vita Suprinity, and poly-ether-ether-ketone (PEEK)). Teeth were subjected to a fracture resistance test with a universal test machine following thermo-cycling. Failure modes were determined by stereomicroscope after the load test. The rest of the endocrowns (n = 48) were produced by Vita Suprinity ceramic and divided into 6 groups (n = 8) according to the cement used (Panavia V5, Relyx Ultimate, and GC cement) with intracoronal cavity depths of 2 and 3 mm. Microleakage tests were performed using methylene blue with stereomicroscope after thermo-cycling. Numerical data for both fracture resistance and microleakage tests were obtained and evaluated by three-way ANOVA. PEEK endocrowns had higher fracture resistance compared to lithium disilicate and Vita Suprinity. Panavia V5 cement had the lowest degree of microleakage, while GC cement had the highest. Different intracoronal cavity depths had no correlation with fracture resistance and microleakage.

Patients undergoing dental treatment may be exposed to complications such as allergic reactions. Patients with symptoms of stomatitis, burning mouth, etc. are usually experiencing hypersensitivity reactions due to the prosthetic materials after the prosthetic rehabilitation,. Patch testing is a diagnostic test for type IV hypersensitivity reactions. Another infrequent complication release after prosthetic treatment can be dermographism. We presented a case and discuss the significance and principles of management. In the presented case, after the prosthodontic treatment, erytheme itch and pain on the oral mucosa were recorded. The patient was allergy tested by means of patch test on the upper back. No irritantion reaction was observed on testing sites. However, red dermographic line of contact has developed with small islands of edema. She was then tested at the clinic for pressure urticaria, and the test was considered positive.

Connecting teeth to osseointegrated implants presents a biomechanical challenge. This is due to the implant being rigidly fixed to the bone and the tooth being attached to the bone with a periodontal ligament. In order to overcome this problem, various connection types such as rigid and nonrigid have been proposed. However, the mechanism of attachment and the perceived problem of the differential support provided by the implant and the tooth have been discussed by many authors, and the ideal connection type is still controversial. The aim of this study was to carry out a review of all available literature addressing the tooth-implant connection and evidence-based understanding of the management of tooth-implant-retained restorations.

Aims Pretreatment of the tooth surface is essential for establishing effective micromechanical retention between it and the restoration. The purpose of this study was to evaluate the bond strength between the resin and the Er, Cr:YSGG laser irradiated dentin and to examine morphologic characterization of the dentin-resin interface. In addition, the study evaluated the quantity of opened and closed dentinal tubules. Subjects and Methods Thirty extracted human molars were sectioned into samples of 1 mm thickness. The samples were randomly assigned to two groups containing 15 specimens each. Surface treatments were not applied to the samples in the control group and the samples in the experimental group were irradiated with an Er,Cr:YSGG laser. Two resin cement samples were polymerized on the surface of each sliced dentin. The micro-shear bond strength (μSBS) between dentin and cement (n = 30 for each group) was measured with a universal testing machine. The topography and morphology of the resin-dentin interface were evaluated by micro-CT (n = 20 for each group). The areas of closed tubular space, closed porosity, area of open tubular space, open porosity, total area of tubular space and fractal dimension were investigated by micro-CT. Statistical analysis used: The data for each parameter were analyzed by Shapiro-Wilk and Student's t test (pResults μSBS values for control group were higher than experimental group. Dentin surfaces in the control group revealed less closed and more opened dentin tubules compared to the experimental group. Total area of tubular space was found to have decreased due to the laser ablation. There was no significant difference between the fractal dimensions of the control and experimental groups. Conclusions The lased dentin surface was not favorable for the bonding mechanism due to alterations in the dentinal structure.

Amalgam tattoos are common, asymptomatic, pigmented oral lesions that clinically exist as isolated, blue, gray, or black macules on the gingival, buccal, and alveolar mucosae, the palate, and/or the tongue. In this case report, the successful use of an erbium, chromium-doped:yttrium, scandium, gallium, and garnet laser for the removal of an amalgam tattoo is explained. A 46-year-old man is presented with a half decade history of an amalgam tattoo on his left maxillary premolar–molar gingiva. Depigmentation procedure was performed under topical anesthesia with the use of an erbium, chromium-doped:yttrium, scandium, gallium, and garnet laser at 2 W in the soft tissue pulsed mode for 10 min. The pigmented tissue was completely removed. The de-epithelialization area healed completely on the 10th day after treatment. The period of healing was uneventful. The amalgam tattoo was completely removed with erbium, chromium-doped:yttrium, scandium, gallium, and garnet laser, and the treated area healed without any adverse effect.

PURPOSE The aim of this study was to determine the efficiency of Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser in different output powers for removing permanent resin cement residues and therefore its influence on microshear bond strength compared to other cleaning methods. MATERIALS AND METHODS 90 extracted human molars were sectioned in 1 mm thickness. Resin cement was applied to surface of sliced teeth. After the removal of initial cement, 6 test groups were prepared by various dentin surface treatment methods as follows: no treatment (Group 1), ethylene diamine tetra acetic acid application (Group 2), Endosolv R application (Group 3), 1.25 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 4), 2 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 5) and 3.5 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 6). The topography and morphology of the treated dentin surfaces were investigated by scanning electron microscopy (n=2 for each group). Following the repetitive cementation, microshear bond strength between dentin and cement (n=26 in per group) were measured with universal testing machine and the data were analyzed by Kruskal Wallis H Test with Bonferroni correction (P