Efficacy of Various Pretreatments on the Bond Strength of Denture Teeth to Denture Base Resins.

OBJECTIVE: This in vitro study evaluated the shear bond strength (SBS) of heat-cured denture base resin (PMMA) to acrylic resin teeth treated with different pretreatments, especially laser irradiation of different powers (1-4 W). MATERIALS AND METHODS: The acrylic resin teeth were separated into seven groups (n = 10) for the following different pretreatments: control group (no surface treatment) (G1), grinding with a tungsten carbide bur (G2), sandblasting (G3), and erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser irradiation at 1 W, 2 W, 3 W, 4 W output powers in (G4-7), respectively. Test specimens were produced according to the PMMA manufacturers' instructions and were subjected to a SBS test at a crosshead speed of 1 mm/min until fracture. Debonded surfaces were evaluated by a stereomicroscope for the type of failure. SEM (scanning electron microscope) analyses were done to estimate the surface changes of the acrylic resin teeth. The data were submitted using a one-way ANOVA and post hoc Tukey-Kramer multiple comparison tests (p = 0.05). RESULTS: The highest bond strength was obtained in G3, and similar SBS values were considered in other groups, and no significant differences were found among the surface treatments and the control group (p < 0.05). All groups had a high percentage of adhesive failures. CONCLUSIONS: Laser irradiations promote surface topography alterations. However laser irradiation of the adhesive surface was found ineffective. The SBS of acrylic resin teeth to a PMMA denture base material is independent of the surface pretreatments Er,Cr:YSGG laser irradiation, sandblasting, and grinding with a carbide bur. All the surface treatments provided a similar bond between the acrylic denture base and the teeth.

Efficacy of Low-Level Laser Therapy in Subjective Tinnitus Patients with Temporomandibular Disorders.

OBJECTIVE AND BACKGROUND: Tinnitus is an apparent sound, perceived in the ear with no stimulus. It has been described as a sound originating from the brain. It affects 17% of the general population. Etiological factors for tinnitus include temporomandibular joint disorders (TMJ, TMD) and Costen's syndrome. The aim of treatment is to eliminate the tinnitus or at least decrease its apparent volume. MATERIALS AND METHODS: In total, 46 patients referred to our department with bilateral subjective tinnitus with TMDs were selected for this study. Low-level laser therapy (LLLT) with an neodymium-doped yttrium aluminum garnet (Nd:YAG) (1064 nm) laser, LLLT with a diode laser (810 nm), and placebo treatment were applied to the patients. There were 15 patients each in the Nd:YAG and placebo groups and 16 patients in the 810 nm diode laser group. LLLT was applied for 10 days, once per day. A visual analog scale (VAS) was used, with values between 0 and 10. VAS scores were recorded before treatment, on the last day of treatment, and 1 month after treatment. The VAS scores were the same on the last day of treatment and 1 month after treatment. The VAS scores before treatment and at 1 month after treatment were compared in a statistical analysis. RESULTS: There were statistically significant differences in the Nd:YAG laser (p = 0.001) and 810 nm diode laser groups (p = 0.005), but no difference in the placebo group (p = 0.065). CONCLUSIONS: Both the Nd:YAG and 810 nm diode lasers were effective for the treatment of subjective tinnitus related to TMDs.

Effectiveness of occlusal splints and low-level laser therapy on myofascial pain.

The present study was designed to evaluate the effects of low-level laser (Nd:YAG) therapy and occlusal splints in patients with signs and symptoms of temporomandibular disorders (TMD) characterized with myofascial pain (MP). A total of 30 patients were selected after being diagnosed with MP according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TDM). The patients were divided into three groups. The first group was occlusal splint (OS) group A (n = 10), the second was low-level laser therapy (LLLT) group B (n = 10), and the last group C was placebo (n = 10). LLLT (1,064 nm, 8 j/cm(2), 250 mW, Fotona) was applied to the patients in the study group once a day for 10 days, for a total of ten sessions. The same parameters and application times were used for placebo group, but the patients were not irradiated. The application was on the trigger points. The patients in the OS group were instructed to wear occlusal splints 12 h/day for 3 weeks. Functional examination was based on RDC/TDM, and pressure pain values were obtained with the Visual Analog Scale. Comparisons were made between the groups before and after the treatment according to Wilcoxon, Mann-Whitney U, and Kruskal-Wallis tests. The pain score values decreased significantly after both LLLT (p < 0.05) and occlusal splint therapy (p < 0.05) compared to placebo group (p < 0.05). There was no significant difference between LLLT and OS groups after treatment (p > 0.05). OS and LLLT are effective for decreasing MP. In addition, this particular type of LLLT is as effective as occlusal splint for pain relief.

Possible protective effect of sertraline against cisplatin-induced ototoxicity: an experimental study.

BACKGROUND/OBJECTIVE: Cisplatin is a widely used chemotherapeutic agent, but its ototoxicity side effect can occur in the majority of patients. Lots of agents were tried to prevent this, but there is not a routine treatment modality yet. The aim of this study was to evaluate the otoprotective effect of sertraline, which is an antidepressant with neuroprotective effects, against cisplatin, in rats. DESIGN: Experimental animal study. MATERIAL AND METHODS: Forty-eight rats were randomly separated in two groups as groups I and II. Group I was identified as the control group and only a single dose of intraperitoneal cisplatin was administered. In group II, in addition to cisplatin, sertraline was administered to the rats through an oral cannula for ten-day period. Distortion product otoacoustic emission measurements were performed at the first day and the 10th day. RESULTS: When the ototoxicity rates after cisplatin in group I and group II in distortion product otoacoustic emission measurements were compared, it was statistically significantly lower in group II in frequencies of 5652, 6165, 6726, 7336, and 7996 Hz (P < 0.05). CONCLUSION: Sertraline seems to have a protective effect on cisplatin ototoxicity and could be used to prevent the ototoxicity and also to treat the depression that occurred in cancer patients together.