Autogenous bone graft in conjunction with enamel matrix derivative in the treatment of deep periodontal intra-osseous defects: a report of 13 consecutively treated patients

AIM: The purpose of the present study was to investigate the effectiveness of a regenerative procedure based on supra-crestal soft tissue preservation in association with combined autogenous bone (AB) graft/enamel matrix derivative (EMD) application in the treatment of deep periodontal intra-osseous defects. METHODS: Thirteen consecutively treated patients, seven females and six males, aged 30-65 years, three smokers, were included. A total of 15 deep, one- to two-wall intra-osseous defects were selected. Immediately before surgery and 6 months after surgery, pocket probing depth (PPD), clinical attachment level (CAL), and gingival recession (REC) were recorded. RESULTS: PPD amounted to 9.4+/-1.8 mm before surgery, and decreased to 4.7+/-1.2 mm post-surgery (p<0.0000). CAL varied from 10.5+/-2.0 mm pre-surgery to 6.2+/-1.7 mm post-surgery (p<0.0000), with CAL gain averaging 4.3+/-1.4 mm. Fourteen (93.3%) defects presented CAL gain >/=3 mm. REC change was 0.4+/-0.7 mm. CONCLUSIONS: Results from the present study indicated that a regenerative procedure based on supra-crestal soft tissue preservation and combined AB/EMD treatment leads to a clinically and statistically significant improvement of soft tissue conditions of deep periodontal intra-osseous defects.     

Effect of pre-cure temperature on the bonding potential of self-etch and self-adhesive resin cements.

OBJECTIVES: To assess whether the pre-cure temperature of resin cements significantly influenced the bonding potential to dentin. METHODS: Forty extracted molars were randomly divided into 8 groups (n=5): Groups (1-4) RelyX Unicem (RU, 3 M ESPE) and Groups (5-8) Panavia F 2.0 (PF, Kuraray Co.), at pre-cure temperatures of 4, 24, 37, and 60 degrees C, respectively. Cements were used in dual-cure mode for luting composite overlays (Paradigm MZ100, 3 M ESPE) to dentin. Microtensile bond strength testing and scanning electron microscope (SEM) observations of cement-dentin interfaces were performed. RESULTS: Group 4 had to be eliminated as RU at 60 degrees C underwent such an accelerated curing that was already set at the time of dispensing. The bond strengths (MPa) measured at refrigerator, room, and intraoral temperature were, respectively: RU 5.4+/-1.7, 11.4+/-6.1, 10.6+/-4.2; PF 7.4+/-3.7, 13.9+/-6.2, 12+/-5.2. The statistical analysis revealed that both luting agents developed a significantly weaker adhesion when used at refrigerator temperature (p<0.05). No statistically significant differences in bond strength were recorded when either cement was used at 24 or 37 degrees C (p>0.05). Pre-heating of PF to 60 degrees C resulted in a significant increase in bond strength (20.7+/-9.4 MPa; p<0.05). SEM observations disclosed an enhanced potential of PF to form a hybrid layer as the temperature increased over 4 degrees C. RU exhibited a less porous and more homogeneous layer at intraoral than at refrigerated temperature. SIGNIFICANCE: It is advisable to let refrigerator-stored resin cements warm up to at least room temperature prior to clinical use. Pre-heating to 60 degrees C enhances the bonding potential of PF.     

Effect of air-drying temperature on the effectiveness of silane primers and coupling blends in the repair of a microhybrid resin composite

PURPOSE: To evaluate the effect of different silane agents and air-drying temperatures on the repair strength of a microfilled hybrid composite. MATERIALS AND METHODS: Composite cylinders (8 x 4 mm) of Gradia Direct Anterior (GC, N=36), stored in a saline solution at 37 degrees C for 1 month, were sandblasted (50-microm aluminium oxide), cleaned (35% phosphoric acid) and randomly divided into six groups (n=6). Two prehydrolyzed silane primers (Monobond-S, Ivoclar-Vivadent, Porcelain Primer, Bisco), a non prehydrolyzed silane primer (Porcelain Liner M, Sun Medical) and three silane/adhesive coupling agents (Porcelain Bond Activator-PBA/Clearfil New Bond, PBA/Clearfil SE Bond, PBA/Clearfil Tri-S Bond, Kuraray) were investigated. Silane-coated surfaces were air dried at two different temperatures (23 degrees C and 38 degrees C) and repairs (8 x 8 mm) were fabricated (Gradia Direct Anterior). Unrepaired composite cylinders (8 x 8 mm, n=6) were used as control to evaluate the cohesive strength of the material. Microtensile bond strength measurements (microTBS) were performed. Results: The silane agent applied (p < 0.001), the airdrying temperature (p < 0.001) and their interaction (p < 0.001) were significant factors (two-way ANOVA, Tukey test; p < 0.05). Silane primers achieved inferior microTBS when air dried at 23 degrees C as compared to silane/adhesive blends. Warm air-drying was significantly beneficial to composite repairs mediated by silane primers. Comparable results were achieved by silane/adhesive couplings at 23 degrees C and 38 degrees C. At 38 degrees C all the intermediate agents resulted in repair microTBS that were comparable to the 24-h cohesive strength of the composite (one-way ANOVA, Dunnett t-tests; p < 0.05). CONCLUSION: The chemical interactions between silane primers and compozite substrate may be optimized through warm airdrying. Silane/adhesive couplings were not influenced by the air drying temperature.     

Accuracy of three electronic apex locators in anterior and posterior teeth: an ex vivo study

Introduction

The aim of this study was to determine in anterior teeth, bicuspids, and molars (1) the accuracy of 3 different electronic apex locators (EALs) in detecting the apical foramen and (2) the accuracy of digital radiography in determining the working length (WL), compared with visible control under a microscope.

Methods

By using radiovideography (RVG), we measured the lengths of 120 root canals with 3 different EALs (Endex, ProPex II, and Root ZX) and compared them with the actual lengths. The accuracy of EALs and RVG was related to each dental category. An endodontic training kit (Pro-Train) was used during experimental procedures.

Results

Statistical analysis showed that the 3 EALs and RVG were less accurate in anterior teeth and molars than in bicuspids. The paired-sample t test showed no statistically significant difference between mesiodistal plane and buccolingual plane digital radiography in all groups.

Conclusions

The 3 EALs tested were more accurate in detecting the apical foramen in bicuspids than in both molars and anterior teeth. Radiographic measurements were not reliable for determining WL in all dental groups in both radiographic planes.     

Effect of curing modes of dual-curing luting systems and root regions on retention of translucent fiber posts in root canals

PURPOSE: To evaluate the effect of different curing modes of dual-curing luting systems and root regions on the push-out strength of fiber posts to intraradicular dentin. MATERIALS AND METHODS: Forty-two extracted premolars with a single root canal were sectioned at the cementoenamel junction and the roots were endodontically treated. The roots were divided into two groups according to two dual-curing luting systems: (1) XP BOND-Dual Cure/Calibra resin cement; (2) XP BOND-Dual Cure/FluoroCore 2. For each luting system, three different curing modes were applied to the dentin adhesive and resin cement: "Self-cure and Self-cure (SC&SC)", "Self-cure and Dual-cure (SC&DC)", and "Dual-cure and Dual-cure (DC&DC)". Translucent Easy fiber posts (Dentsply Maillefer) were luted in the roots. A thin-slice push-out test was performed, and the data of push-out strength were analyzed using three-way ANOVA with luting system, curing mode, and root region (apical, middle and coronal) as factors. Tukey's test was used for post-hoc comparisons. RESULTS: The push-out strength of XP BOND-Dual Cure/Calibra was significantly lower when Calibra resin cement was self-cured than when it was dual-cured (SC&SC: 6.04 +/- 2.65 MPa; SC&DC: 10.69 +/- 3.01 MPa; DC&DC: 10.72 +/- 3.63 MPa; p < 0.05). The curing modes did not affect the push-out strength of XP BOND-Dual Cure/FluoroCore 2 (SC&SC: 7.90 +/- 3.94 MPa; SC&DC: 8.32 +/- 2.73 MPa; DC&DC: 9.27 +/- 4.12 MPa; p > 0.05). The coronal push-out strength was significantly higher than the apical push-out strength (p < 0.05). CONCLUSION: Retention of fiber posts in root canals was affected by the curing modes of dual-curing luting system and root regions.     

Placement of fiber prefabricated or custom made posts affects the 3-year survival of endodontically treated premolars

PURPOSE: To assess whether the amount of residual coronal dentin and the placement of a prefabricated (DT Light Post) (LP) or a customized fiber post (Ever Stick Post) (ES) have a significant influence on the 3-year survival of endodontically treated premolars. METHODS: A sample of 345 patients provided six groups of 60 premolars in need of endodontic treatment. Groups were defined based on the amount of dentin left at the coronal level after endodontic treatment and before abutment build-up. Within each group teeth were randomly divided into three subgroups (n = 20). In Subgroup A, no root canal retention was provided for the coronal restoration. In Subgroups B and C, LP and ES, respectively, were placed inside the root canal. All the teeth were finally restored with a single unit metal-ceramic crown. RESULTS: Data were not affected by any loss to follow-up. The overall 36-month survival rate of crowned endodontically treated premolars was 76.7%. The lowest survival rate was recorded for teeth restored without any root canal retention (62.5%). Teeth restored with LP had a survival rate higher (90.9%) than those restored with ES (76.7%). The Cox regression analysis showed that the presence of root canal retention was a significant factor for survival (P < 0.05). The decrease in failure risk was higher in teeth restored with LP (HR = 0.1; 95% CI for HR = 0.09 to 0.34; P < 0.001) than when using ES (HR = 0.5; 95% CI for HR = 0.3 to 0.7; P = 0.003). Teeth retaining one (HR = 0.3; 95% CI for HR = 0.2 to 0.7; P = 0.003), two (HR = 0.2; 95% CI for HR = 0.1 to 0.5; P < 0.001), or three coronal walls (HR = 0.1; 95% CI for HR = 0.05 to 0.3; P < 0.001) had a significantly lower failure risk than teeth deprived even of the ferrule effect. Similar failure risks existed for teeth missing all the coronal walls regardless of the presence or absence of a ferrule effect (P > 0.05). Interaction terms were not significant (P > 0.05). Post placement and the amount of residual coronal dentin affected the 3-year survival of endodontically treated premolars.     

Myoepithelial carcinoma of the submandibular gland: report of a case with multiple cutaneous metastases

Myoepithelial carcinoma is a rare and aggressive neoplasm of the salivary glands. One-third of the patients may develop regional distant metastases, and lungs and kidneys have been regarded as the most usual sites for implantation. There is, however, little information on the metastatic behavior of this malignancy. We report the first case of patient with multiple cutaneous metastases from a myoepithelial carcinoma of the submandibular gland, which depicted a very aggressive clinical course.