Retention of luting agents used for implant-supported restorations: A comparative In-Vitro study.

AIMS: The aim of this study was to compare the retention of different luting agents used with implant-supported restorations. MATERIALS AND METHODS: A total of 90 custom metal frameworks and copings were prepared and divided into six different luting agent groups (n = 15/group): polycarboxylate cement (PC), resin-modified glass-ionomer cement (RMGIC), two self-adhesive resin cements (SARC), copper-ion zinc-phosphate cement (CZPC), and non-eugenol temporary resin cement (TRC). After sandblasting with 50 µm Al2O3, the copings were cemented on frameworks and stored in artificial saliva for 48 h at 37°C and thermocycled between 5-55°C for 37,500 cycles. Samples were subjected to tensile testing by a universal testing machine, and data were statistically analyzed. RESULTS: The differences between the retention values of types of cement were significant (P < 0.05). The maximum retention value was calculated for CZPC (755,12 ± 55 MPa) while the lowest value was for TRC (311,7 ± 61 Mpa). CONCLUSION: Neither of the tested cement had superiority over another to ensuring retention. The types of cement presented were meant to be a discretionary guide for the clinician in deciding the amount of the desired retention between castings and abutments.

Effects of different surface conditioning methods on the bond strength of composite resin to amalgam.

Repairing amalgam restorations with composite resins using surface conditioning methods is a conservative treatment approach. This study investigated the effects of different conditioning methods that could be used for repair of amalgam fractures. Amalgam (N=96) was condensed into cavities within autopolymerizing polymethylmethacrylate (PMMA), and the exposed surface of each specimen (diameter, 6 mm; thickness, 2 mm) was ground finished. The specimens were randomly divided into nine experimental groups (n=12 per group), depending on the conditioning method used. The control group had natural central incisors with amalgam (n=12). The combination of the following conditioning methods was tested: silicacoating (Sc), sandblasting (Sb), metal primers, coupling agents, fiber (Fb) application, and opaquers (O). Five types of silanes, metal primers, or adhesives (Visiobond [V], Porcelain Photobond [PP], Alloy Primer [AP], Unibond sealer [Us], ESPE-Sil [ES]), and four opaquers, namely, Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and an experimental Opaquer (EO-Cavex), were used. The groups were as follows: group 1, Sc+ES+S+V; group 2, Sc+ES+CstO+V; group 3, Sc+ES+M+V; group 4, Sc+ES+EO+V; group 5, Sb+AP+S; group 6, Sb+AP+PP+CstO; group 7, Sc+ES+S+Fb+V+Fb; group 8-control, SC+ES+V; and group 9, Etch+Sc+ES+S+Us. One repair composite was used for all groups (Clearfil Photo Bond Posterior, Kuraray, Tokyo, Japan). Shear bond strengths (SBSs) (MPa ± SD) were evaluated after 5 weeks of water storage (analysis of variance [ANOVA], Tukey honestly significant differences [HSD], α=0.05). Group 1 exhibited significantly higher values (35.5 ± 4.1) than were seen in group 4 (19.4 ± 8.9), group 6 (19.1 ± 7.8), and group 8 (20.1 ± 4.1) (p<0.05). Group 9 exhibited significantly lower values (8.3 ± 3.4) than were noted in groups 1 to 3 (35.5 ± 4.1; 27 ± 12.5; 24.4 ± 5.1, respectively) (p<0.05). Group 7 (16.4 ± 5.9) showed significantly lower values than were observed in group 1 (35.5 ± 4.1) (p<0.05). Surface conditioning techniques affected the bond strengths of composite adhesion to amalgam. Experimental opaquer exhibited lower values. Leaving a small border of enamel around the restoration decreased the bond strength.

Colour stability of sectional laminate veneers: A laboratory study.

BACKGROUND: This study aimed to evaluate the colour stability of sectional laminate veneers (SLVs) fabricated with four and cemented with two different materials. METHODS: Eighty SLVs were prepared with a thickness of 0.2-0.4 mm from IPS e.max CAD, Lava Ultimate, CEREC Blocs and IPS InLine and were cemented with Variolink Veneer and Variolink N to form eight groups (n:10). After cementation, specimens underwent 5000 thermocyles prior to immersion in a coffee solution. RESULTS: Colour change before and after thermal cycling did not reveal significant differences (P > 0.05). After coffee immersion, significant colour change was observed in all groups (P > 0.05). Only IPS InLine cemented with Variolink Veneer was considered clinically acceptable (∆E < 3.3). According to observer scorings, marginal discolouration was higher in Lava Ultimate, while no discolouration was observed in IPS InLine. Dual or light-curing resin cements showed insignificant differences. CONCLUSIONS: SLVs fabricated with different aesthetic materials underwent perceptible (∆E > 3.3) discolouration except for the IPS InLine cemented with light-curing resin cement. Cementation with either dual-curing or light-curing resin cements does not by itself affect colour stability. The highest marginal discolouration was in the Lava Ultimate group while no discolouration was detected in the IPS InLine group.

Alveolar hydatid disease of the brain. Report of four cases.

Four cases of alveolar hydatid disease of the brain encountered within 27 months in eastern Turkey are reported. All of the patients were male farmers who presented with signs of cerebral tumor. Two of the patients were shown to harbor hepatic lesions and one of them had pulmonary metastases. The cerebral lesions were removed in toto and neurological recovery was obtained in all four patients. A review of the literature revealed only five previously reported cases treated surgically. It is concluded that cerebral Echinococcus multilocularis lesions are amenable to surgery, and that their removal provides useful prolongation of life despite the presence of hepatic or pulmonary disease.

Cavernous hemangioma in a child presenting with hemichorea: response to pimozide.

The case of a 9-year-old boy with hemichorea due to cavernous hemangioma in the left caudate nucleus is presented. To our knowledge, only two children have been reported with hemichorea associated with cavernous hemangioma. Hemichorea in our patient responded to pimozide, a neuroleptic that blocks central nervous system dopaminergic receptors.

Comparison of five antimicrobial regimens for the treatment of brucellar spondylitis: a prospective, randomized study.

Brucellosis, a zoonosis with worldwide distribution, is a systemic infection and still an important public health problem in Turkey. The best antimicrobial combination and schedule for the treatment of brucellosis with spondylitis has not yet been clearly determined. In a prospective and randomized study, we compared the efficacy of five antimicrobial regimens for treatment of 102 patients with lumbar brucellar spondylitis. Patients were randomly assigned to receive antimicrobial combination therapy. Twenty patients received streptomycin 1 g/day intramuscularly for 15 days and tetracycline-HCl, 500 mg every 6 h orally for 45 days (ST), 21 patients received streptomycin 1 g/day i.m. for 15 days and doxycycline 100 mg every 12 h orally for 45 days (SD), 20 patients received doxycycline 100 mg every 12 h orally for 45 days and rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (DR), 19 patients received ofloxacin, 200 mg every 12 h orally for 45 days and rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (OR), and 22 patients received streptomycin 1 g/day i.m. for 15 days and doxycycline 100 mg every 12 h orally for 45 days plus rifampicin 15 mg/kg per day in a single morning dose orally for 45 days (SDR). Initial therapeutic failure occurred in 2 patients (10%) in the ST regimen group, 4 patients (19%) in the SD group, 3 patients (15%) in the DR group and 5 patients (26%) in the OR regimen. In addition, 2 patients (10%) in the DR group and 5 patients (26%) in the OR regimen relapsed during the follow-up period. There was no relapse in any patients in the ST, SD, and SDR groups. The response rates were 90% in the ST and 81% in the SD groups. In contrast, there was a maximum good response (100%) and no relapse in the SDR group. In conclusion, a combination of doxycycline, streptomycin, and rifampicin can be recommended as therapy for brucellar spondylitis and to reduce relapse rates.