Tooth Discoloration Induced by Different Calcium Silicate-Based Cements: A Two-Year Spectrophotometric and Photographic Evaluation in Vitro.

OBJECTIVE: Calcium silicate-based cements (CSCs) may lead to coronal staining in young permanent teeth over the time. The purpose of this study was to evaluate and compare the long-term tooth discoloration induced by different CSCs. STUDY DESIGN: Ninety freshly-extracted human molars were assigned randomly into 6 groups (n=15/group) according to the CSC used as a pulpotomy material: ProRoot MTA, MTA Angelus, NeoMTA, EndoSequence Putty, Biodentine and Negative control (No cement). The color was assessed at baseline, and thereafter at 3, 6, 12 and 24 months by using both a spectrophotometer and digital images taken with and without a cross-polarizing filter. The time-dependent changes in color (ΔE) were compared within and among groups using Analysis of Variance. RESULTS: Angelus MTA and ProRooT MTA showed severe coronal discoloration (p>0.05) starting at 3 months. ΔE values of NeoMTA, EndoSequence Bioceramic Putty and Biodentine were below the perceptibility threshold, with Biodentine showing greater ΔE values than NeoMTA and EndoSequence Putty in the absence of statistical significance (p>0.05). CONCLUSIONS: Discoloration elicited by CSCs may develop soon after placement, and continue to increase for up to two years. Angelus MTA and ProRooT MTA cannot be recommended for vital pulp therapies in the esthetic zone of young individuals.

Effect of different pretreatment methods on dentin bond strength of a one-step self-etch adhesive.

AIM: The aim of this in vitro study was to evaluate the shear bond strength of a one-step self-etch adhesive to dentin pretreated with phosphoric acid, air abrasion, or laser. METHODS AND MATERIALS: Fifty-six extracted non-carious human mandibular molars were mounted and the occlusal surfaces ground with a mechanical grinder to obtain flat occlusal dentin surfaces. The teeth were randomly divided into four groups of 14 teeth according to the different dentin surface pretreatment methods: Group I--acid, Group II--laser, Group III--air abrasion, Group IV (control)--no surface treatment. After applying a one-step self-etch adhesive system, Futura Bond NR, cylinders of Z250 composite resin were bonded to the dentin surfaces by transparent gelatin capsules (2.5 mm diameter; 3 mm high) and then polymerized. All specimens were stored in distilled water at 37 masculineC for 24 hours. Shear bond testing was carried out using an Universal testing machine with a crosshead speed of 0.5 mm/sec. Data were analyzed using the Kruskal Wallis and Mann-Whitney tests at a significance level of 0.05. RESULTS: The bond strength of air abrasion (Group III) and the control group (Group IV) were statistically higher than both the acid (Group I) and laser (Group II) pretreatments (p < 0.05). No statistically significant differences were found in shear bond strength between surfaces treated with air abrasion and the control group (p > 0.05). Surfaces pretreated with laser (Group II) resulted in the lowest bond strength which was not statistically different from those pretreated with acid (Group I) (p > 0.05). CONCLUSION: Surfaces pretreated with acid and laser adversely affected the bond strength of a one-step self-etch adhesive, Futura Bond NR, while pretreatment with air abrasion had no effect on bond strength. CLINICAL SIGNIFICANCE: The pretreatment of dentin surfaces prior to self-etch adhesive seems to be unnecessary and defeats the original purpose of these systems.

Bond strength of one-step self-etch adhesives and their predecessors to ground versus unground enamel.

OBJECTIVE: The aim of this study was to compare the shear bond strength of several self-etch adhesives to their two-step predecessors to ground and unground enamel. METHODS: Seventy-five extracted, non-carious human third molar teeth were selected for this study. The buccal surfaces of each tooth were mechanically ground to obtain flat enamel surfaces (ground enamel), while the lingual surfaces were left intact (unground enamel). The teeth were randomly divided into five groups according to the adhesive systems (n=15): one-step self-etch adhesive - Clearfil S3 Bond, its two-step predecessor - Clearfil SE Bond, one-step self-etch adhesive - AdheSE One, and its two-step predecessor - AdheSE, and a two-step etch-and-rinse adhesive - Adper Single Bond 2(control). After application of the adhesives to the buccal and lingual enamel surfaces of each tooth, a cylindrical capsule filled with a hybrid composite resin (TPH) was seated against the surfaces. The specimens were stored in distilled water at 37°C for 24 hours, followed by thermocy-cling (5°C-55°C/500 cycles). They were subjected to shear bond strength test in a universal testing machine at a crosshead speed of 1.0 mm/minute. The data were compared using a two-way ANOVA, followed by Bonferroni test at P<.05. RESULTS: All adhesives exhibited statistically similar bond strengths to ground and unground enamel except for the etch-and-rinse adhesive that showed significantly higher bond strengths than the self-etch adhesives (P<.05). No significant differences in bond strength values were observed between ground and unground enamel for any of the adhesives tested (P=.17). CONCLUSION: Similar bond strengths to ground and unground enamel were achieved with one-step self-etch adhesives and their predecessors. Enamel preparation did not influence the bonding performance of the adhesives tested.

Effect of repeated firings on microtensile bond strength of In-Ceram Alumina with two different veneering ceramics.

Microtensile bond strengths of In-Ceram Alumina cores veneered with two ceramics after different numbers of firing cycles were evaluated. After In-Ceram Alumina cores were fabricated, they were veneered with either Vitadur Alpha or Vita VM7. A control group of each core-veneer combination was fired twice, and a second group was fired five times to induce thermal fatigue. Obtained microbars were subjected to microtensile bond strength tests. Data were analyzed using two-way analysis of variance. Microtensile bond strength values for Vita VM7 specimens were higher than those for Vitadur Alpha (P < .001). Although the number of firing cycles revealed no change in bond strength, the veneering material proved to be an important factor.

Non-surgical treatment of sports-related temporomandibular joint disorders in basketball players.

In this study, 18 basketball players (11 female, seven male; age range 14-32 years) with temporomandibular joint (TMJ) problems who had a history of sport injuries related to head or jaw region were evaluated and the results of the treatment were presented. A standardized functional examination of the masticatory system was performed including measurement of maximal jaw movements, recording of joint sounds, pain on movement of the jaw as well as tenderness to palpation of the both TMJ or masticatory muscles. Patients were also evaluated periodontally. Diagnosis was made according the criteria, described by Okeson, and appropriate treatment was applied using different kind of splints. At the end of treatment only one patient continued with right TMJ reduction with slight pain. Except for that patient, none of the patients had pain after treatment. The maximum opening of the jaws and the maximal jaw movements were statistically increased after treatment. Patients with TMJ problems also showed periodontal problems, most likely due to inadequate oral hygiene because of the limited jaw movements and pain. Periodontal parameters including probing depth (PD), Plaque index (PI), and Sulcus Bleeding Index (SBI) improved after treatment. Sports-related TMJ injuries may result in complex problems such as pain, TMJ sounds, limitation in maximal jaw movements and maximum opening of the mouth, difficulty in chewing. With the appropriate diagnosis this could be treated non-surgically in 6-8 months. This study also showed that the TMJ disorders may cause periodontal problems, which may affect all teeth and also the general health of the athlete.