Comparative evaluation of cervical pulpotomy and pulpectomy for primary molars with irreversible pulpitis: a multicentre randomised controlled trial.

PURPOSE: The objective of this multicentre randomised controlled trial was to compare the clinical/radiographic outcomes of cervical pulpotomy using calcium-enriched mixture cement (PCEM) and pulpectomy using Metapex (PM) in primary molars with irreversible pulpitis (IP). METHODS: A total of 134 primary molars from 94 children were randomly assigned to two intervention groups: the PCEM group (n = 74) and the PM group (n = 60). Baseline characteristics including age/gender/molar type/tooth type/jaw were recorded. The primary outcome measures were clinical/radiographic success rates assessed at the first and second follow-up appointments. Secondary outcomes included reasons for clinical/radiographic failures. Multiple logistic regression analysis was performed to determine the impact of various factors on the success rates. RESULTS: The mean age of the participants in both groups was similar (PCEM group: 5.4 years, PM group: 5.5 years). Gender distribution, molar type, tooth type, jaw, and number of practitioners were comparable between the groups. The clinical success rate at the first follow-up was 98.6% in the PCEM group and 96.4% in the PM group. At the second follow-up, the clinical success rate was 97.1% in the PCEM group and 91.1% in the PM group. The radiographic success rates at the first and second follow-up were 98.6% and 96.4% in the PCEM group and 96.4% and 91.1% in the PM group, respectively. Multiple logistic regression analysis did not reveal any significant association between the success rates and age/gender/molar type/jaw, or treatment groups (P > 0.05). CONCLUSION: In primary molars with IP, both simple/conservative cervical pulpotomy using calcium-enriched mixture cement and pulpectomy using Metapex demonstrated high clinical/radiographic success rates. No significant differences were observed between the two treatment modalities. These findings suggest that both techniques can be considered effective treatment options for managing primary molars with IP. TRIAL REGISTRATION NUMBER: Trial registration number: IRCT20201226049838N1, retrospectively registered on 12 January 2021.

The occurrence of flexion-relaxation phenomenon in elite cyclists during trunk forward bending.

Flexion-relaxation phenomenon (FRP) is a well-known phenomenon in spinal extensor muscles. According to the literature, prolonged flexed posture leads to creep phenomenon and affects the active and passive neuromuscular control of the spinal column. The purpose of this study was to investigate FRP occurrence in elite cyclists that prolonged flexion posture is an integral part of their professional life. Their muscles' contraction pattern during forward bending was also compared. Electromyography (EMG) was recorded during flexion and extension from standing position in thoracic erector spinae (TES), lumbar erector spinae (LES) and gluteus maximus (Gluteus max) in 15 healthy male elite cyclists. In addition, the kinematic data related to the trunk angles were simultaneously recorded by a motion analysis system. Two-way ANOVA was used to assess the effects of muscle group and direction of movement on maximum amplitude of EMG activity. Among 15 cyclists, FRP was detectable in 60%, 87% and 73% of the participants in TES, LES and Gluteus max, respectively, and happened between 74% and 82% of the trunk flexion. There was no statistically significant difference in onset and offset of muscles FRP. Despite prolong hyper kyphotic posture, FRP was identifiable in TES, LES and Gluteus max muscles of elite cyclists.

Effect of bonding application time on the microleakage of Class V sandwich restorations.

BACKGROUND: The aim of this study was to assess the effect of bonding application time on the microleakage of Class V sandwich restorations. METHODS: Eighty non-carious third molars were randomly divided into 16 groups. Two Class V cavities were prepared on the buccal and lingual surfaces of teeth. Three groups were restored with Fuji II GIC and treated with a total-etch bonding system (Stea/SDI) immediately after insertion, at 7 minutes and 15 minutes after mixing the glass ionomer cements (GICs). Another three groups were restored with Riva Self Cure GIC and treated with the total-etch system identically. The other six groups were subjected to self-etching bonding (Frog/SDI) after GIC placement in an identical procedure. The remaining groups were made using light cure GICs (Fuji II or Riva Light Cure) in conjunction with the total-etch or self-etching systems. Cavities were then restored with composite (Valux plus, 3M/ESPE). Samples were subsequently immersed in 2% methylene blue solution for 48 hours and observed under a stereomicroscope after sectioning. Four-scale grading was used to assess microleakage in occlusal and gingival walls. Data were analysed using Kruskal-Wallis and Mann-Whitney tests. RESULTS: The self-etching bonding system exhibited more microleakage in occlusal margins regardless of time. Over time, microleakage significantly decreased in gingival margins in all self-cure groups except for Riva Self Cure treated with the total-etch system (p < 0.05). CONCLUSIONS: Bonding application time had no effect on the microleakage of occlusal margins. However, maturation of GICs induced a decreased microleakage in gingival margins.