Ahmet Saracoglu

Pilot study of unidirectional E-glass fibre-reinforced composite resin splints: Up to 4.5-year clinical follow-up

OBJECTIVES This prospective clinical pilot study evaluated the performance of fibre-reinforced-composite resin (FRC) splints on mandibular anterior teeth. METHODS Between June-2003 and January-2008, 19 patients (7 females, 12 males, 45-72 years old) from a group of consecutive patients who completed periodontal therapy received E-glass FRC splints (everStick Perio, StickTech) in combination with two types of flowable and restorative resin-composites (Filtek Flow, Filtek Supreme, n=11; Tetric Flow, Tetric-Ceram, n=8). Only patients with vital teeth, presenting mobility of grade 3, having at least one canine with no mobility on both sides of the dental arch were assigned for a splint therapy. The patients were recalled for periodical follow-up controls first at 6 months and thereafter annually. The evaluation protocol involved technical failures [chipping, debonding or fracture (tooth/restoration)] and biological failures (caries)]. Periodontal pocket depth (PPD) and clinical attachment level (CAL) were measured 6 months after splinting and annually. Six sites were measured for each natural tooth at the mesiobuccal, buccal, distobuccal, distolingual, lingual and mesiolingual sites. RESULTS All splints were applied from canine to canine in the mandible. In total, 5 recalls were performed and no drop-out was experienced. One partial debonding of the FRC splint with Tetric Flow/Tetric-Ceram combination was observed after 40 months. No caries was found around any of the splints and no teeth had to be extracted until the final follow up. The splinted teeth were found to be vital in the vitality tests. Overall survival rate was 94.8% (Kaplan-Meier). The survival rate was not significantly affected by the composite type (Filtek-Flow/Filtek Supreme: 100%, Tetric Flow/Tetric Ceram: 96% (p=0.92) [Kaplan-Meier, Log Rank (Mantel-Cox) (CI=95%)]. Hazard ratio for Tetric Flow/Tetric Ceram group was 0.05 (95% CI) and for Filtek Flow/Filtek Supreme group 0.00 (95% CI). Whilst overall PPD measurements of the dentition ranged between 6 and 12 mm, the CAL measurements ranged between 4.9 and 10mm at baseline. The mean PPD for the splinted teeth decreased from 8.9±1.8 mm to 5.2±1.2 mm, and CAL decreased from 7.2±1.6 mm to 4.6±1 mm at the end point. CONCLUSION Direct tooth splinting with E-glass FRC material performed successfully up to 4.5 years. Periodontal status of the splinted teeth showed decreased PPD and CAL.

Adhesion of resin composite to hydrofluoric acid-exposed enamel and dentin in repair protocols

Intraoral repairs of ceramic fixed-dental-prostheses (FDP) often include cervical recessions that require pretreatment of the exposed tooth surfaces either before or after the ceramic is conditioned with hydrofluoric (HF) acid gel. The sequence of repair protocol may cross-contaminate the exposed etched enamel or dentin surfaces during the application or rinsing process and thereby affect the adhesion. This study evaluated the influence of HF acid gel with two concentrations on bond strengths of composite to enamel and dentin. Human third molars (N=100, n=10 per group) with similar sizes were selected and randomly divided into 10 groups. Flat surfaces of enamel and dentin were created by wet ground finishing. Before or after the enamel (E) or dentin (D) was conditioned with phosphoric acid (P), substrate surfaces were conditioned with either 9.5% HF (HF(9.5)) or 5% HF (HF(5)). Subsequently, a bonding agent (B) was applied. The experimental groups by conditioning sequence were as follows where the first letter of the group abbreviation represents the substrate (E or D) followed by the acid type and concentration: group 1 (EPHF(9.5)), group 2 (EPHF(5)), group 3 (EHF(9.5)P), group 4 (EHF(5)P), group 5 (DPHF(9.5)), group 6 (DPHF(5)), group 7 (DHF(9.5)P), and group 8 (DHF(5)P). Group 9 (EPB) and group 10 (DPB) acted as the control groups. Repair resin was adhered incrementally onto the conditioned enamel and dentin in polyethylene molds. Each layer was photo-polymerized for 40 seconds. All specimens were thermocycled (×1000, 5°-55°C) and subjected to shear test (universal testing machine, 1 mm/min). Specimens that debonded during thermocycling were considered as 0 MPa. The bond strength data were analyzed using Kruskal-Wallis test and failure types using the chi-square test (α=0.05). Overall, the bond results (MPa) were lower on dentin than on enamel (p<0.01). EPB (25.6 ± 6.6) and DPB (20.2 ± 4.9) control groups showed significantly higher results than those of other groups (p<0.05). While higher mean bond strengths were obtained in group 1 (EPHF(9.5)) (11.5 ± 2.1) and group 2 (EPHF(5)) (7.3 ± 0.6), lower results were obtained when HF acid gels were applied prior to phosphoric acid (EHF(9.5)P: 5.0 ± 1.1, EHF(5)P: 3.6 ± 0.1) (p<0.05). On dentin, the results were the lowest in group 8 (DHF(5)P: 1.5 ± 1.6), being significantly lower than those of group 5 (DPHF(9.5)) (p<0.05). Scanning electron microscope (SEM) images revealed predominantly mixed failures with less than half of the composite left on both enamel and dentin surfaces (64 out of 80) (p<0.05), indicating that in general, adhesion was not ideal. Contamination of the enamel or dentin surfaces with HF acid gel impairs the bond strength of composites. Considering both the bond strength results and failure types, when dental tissues are to be repaired next to ceramic, application of phosphoric acid before HF acid gel application can be recommended. HF acid gel concentration did not influence the results except on enamel.

Clinical Study on the Comparison of Masticatory Efficiency and Jaw Movement Before and After Temporomandibular Disorder Treatment

Abstract In this clinical study, pre- and post-rehabilitation changes in intraborder mandible movements, chewing cycles, masticatory efficiencies, and borders of the chewing area of patients with unilateral muscular disorders (MD) (n=20) or unilateral disc derangement disorders (DDD) (n=20) of temporomandibular disorder (TMD) were observed and compared with healthy individuals with full dentition (n=20) (48 female, 12 male; mean age: 28). The MD patients received stabilization splints and the DDD patients, anterior positioning splints for six weeks. Symptoms, such as muscle pain, TMJ pain, headache, chewing difficulty, and maximum mouth opening, showed significant improvements after splint therapy for both MD (p=0.000) and DDD (p=0.000) patients, but lateral excursion and protrusion were not significantly changed (p>0.05). Chewing efficacy and chewing cycles improved significantly (p<0.05) in both the MD (p<0.05) and DDD (p<0.05) groups, but only the MD group was comparable to the control group after treatment. Pre- and post-rehabilitation chewing cycles along the frontal plane on both sides in the MD group were similar to the control group. Considering the majority of the improvements in the diagnostic measures, patients with MD and DDD may benefit from occlusal splint therapy.