C. Stavrianos

The Influence of the Smear Layer on Dentinal Tubule Penetration Depth by Three Different Root Canal Sealers: An In Vitro Study

The effect of the smear layer on the penetration depth of three different root canal sealers into the dentinal tubules was examined in 64 recently extracted single-rooted teeth. After chemomechanical preparation, the samples were randomly divided in two equal groups. The smear layer remained intact in group A, whereas complete removal of the smear layer was performed in group B. Two roots from each group were used as controls. Ten roots from each group were obturated with laterally condensed gutta-percha points and sealers AH Plus, Apexit, and Roth 811, respectively. Examination in scanning electron microscope revealed that the smear layer obstructed all the sealers from penetrating dentinal tubules. In contrast, smear layer removal allowed the penetration of all sealers to occur to a varying depth. These findings suggest that smear layer plays an important role in sealer penetration into the dentinal tubules, as well as in the potential clinical implications.

Adhesion of a New Methacrylate Resin-Based Sealer to Human Dentin

The purpose of this study was to compare the shear bond strength of four root canal sealers: Fibrefill (a methacrylate resin sealer), Endion (a glass ionomer sealer), Topseal (an epoxy resin sealer), and CRCS (a calcium hydroxide sealer) to human root canal dentin. The dentin specimens were divided into four groups of 12 specimens each and etched with 3 ml of EDTA 17% before rinsing with NaOCl 2.5% and distilled water. Bond strength was tested using a test machine by subjecting samples to a shear load at a cross-head speed of 0.5 mm/min. The best results were observed in the Fibrefill group, in which the mean shear bond strength was 7.993 +/- 2.365 MPa. The values in the Endion (1.816 +/- 0.614 MPa) and CRCS (2.224 +/- 0.509 MPa) groups were significantly lower than in the Fibrefill and Topseal (6.235 +/- 1.428 MPa) groups. Inspection of the fractured surfaces revealed the bond failure to be mainly adhesive to dentin for Fibrefill and cohesive for Endion sealer. CRCS and Topseal sealers showed both adhesive and cohesive failures.

Shear bond strength of AH-26 root canal sealer to dentine using three dentine bonding agents

OBJECTIVE The purpose of the study was to compare the bond strength of AH-26 root canal sealer to human root canal dentine exposed to different intracanal medications both with and without the use of three bonding agents. The materials used were AH-26 sealer, two one-bottle bonding agents (Single Bond, Bond-1) and one self-etching bonding agent (Clearfill SE Bond). METHODS The dentine substrate was obtained from single rooted human teeth. The dentine specimens were treated either with EDTA 15% or phosphoric acid 37% to achieve the removal of smear layer. The AH-26 sealer was placed on the dentine surfaces both with and without the use of the bonding agents. Bond strength was tested using a single plane shear test assembly. RESULTS The SBS values were (MPa): Group A (EDTA-AH-26) 3.678+/-0.853, Group B (Phosphoric acid-AH-26) 3.470+/-0.834, Group C (EDTA-Single Bond-AH-26) 4.8+/-0.865, Group D (Phosphoric acid-Single Bond-AH-26) 5.043+/-1.022, Group E (EDTA-Bond 1-AH-26) 4.939+/-0.877, Group F (Phosphoric acid-Bond 1-AH-26) 5.101+/-1.117, Group G (Clearfill SE Bond-AH-26) 6.975+/-1.694. The use of dentine bonding agents improved significantly (p<0.05) the adhesion of AH-26 sealer with the root canal dentine. However, the best results were obtained with the self-etching system. Similar results were observed from the pretreatment of dentine either with phosphoric acid 35% or EDTA 15%. CONCLUSIONS The use of dentine bonding agents gave higher shear bond strengths of AH-26 sealer to human root canal dentine.

Depth of penetration and appearance of grossman sealer in the dentinal tubules: An in vivo study

Five teeth extracted after chemomechanical preparation (group A) and 11 extracted 1 to 7 yr after endodontic treatment (group B) were selected for this study. A 1% NaOCl was used for irrigations and a lateral condensation technique with a Grossman-type sealer was used for obturation. The teeth were fractured and prepared for and viewed by a scanning electron microscope equipped with an electron dispersive spectrometer. All root canal walls of group A were covered with a thick smear layer. Sealer, either rod-like or granular in appearance and barium free, was present in the majority of the dentinal tubules of group B usually at a distance up to 200 microns from the root canal walls; in two cases up to 900 microns. Sealer was found deepest in the middle third of the root. The smear layer did not stop sealer from entering the dentinal tubules. The differences in the depth of penetration or in the appearance of the sealer cannot be attributed to the different time periods the teeth remained in the arch after endodontic treatment.

Upper-lip laser frenectomy without infiltrated anaesthesia in a paediatric patient: a case report

Labial frenectomy is a common surgical procedure in the field of oral surgery. Labial frenectomy is a procedure usually done for orthodontic reasons. The role of laser surgery in the oral cavity is well established. The use of diode laser frenectomy without infiltrated anaesthesia is currently under investigation. Needle-less oral surgery, without infiltrated anaesthesia, is a novel situation in paediatrics with paramount importance.

Short‐ and long‐term sealing ability of Gutta‐flow and AH‐Plus using an ex vivo fluid transport model

AIM To use the fluid transport model to evaluate the ex vivo short- and long-term microleakage along root canals filled with Gutta-flow or AH-Plus using the cold lateral compaction technique. METHODOLOGY A total of 38 single-rooted human teeth were used for the assessment of microleakage. The crowns of the teeth were sectioned below their cemento-enamel junctions to adjust the length of the roots to approximately 15 mm. The root canals were instrumented using the step-back technique and filled using cold lateral condensation. The sealer employed was either Gutta-flow (Group A) or AH-Plus (Group B). Microleakage along the root canals was evaluated using a fluid transport model after periods of 1 week and 3 months. RESULTS The microleakage values (microL h(-1)) for group A were 0.36 +/- 0.33 at 1 week and 0.41 +/- 0.36 at 3 months. Group B showed mean microleakage values 0.2 +/- 0.31 at 1 week and 0.28 +/- 0.38 at 3 months. Statistical analysis indicated no significant differences (P > 0.05) between the two groups after either 1 week or 3 months. CONCLUSIONS There was no significant difference between AH-plus and Gutta-flow in terms of sealing ability.

Radiographic evaluation of bone regeneration after the application of plasma rich in growth factors in a lower third molar socket: a case report

A 42-year-old Mediterranean male presented complaining of inability to sustain good oral care at the posterior aspect of the lower right jaw. The main problems were food impaction in the area and the subsequent malodor. The patient reported remarkable medical history. Clinical examination revealed local erytherma with noticeable bone defect distal to the second molar with obvious defect in the mesial wall of the third molar; the penetration depth was found to be up to 6 mm.Radiological evaluation confirmed the defect and it was attributed to the mesioangularly partially impacted lower third molar. It was decided that third molar should be extracted and concentrate of the patients growth factors (PRGF) to be applied into the bony defect to stimulate bone regeneration and promote healing.The third molar tooth was, then, removed surgically and the PRGF, which was prepared preoperatively, was implanted in the socket. At the first postoperative day, moderate pain was the main complaint and was controlled by NSAIDs. One week postoperatively, the sutures were removed and there was good tissue healing on examination.On the fiftieth postoperative day, radiographic evaluation took place and showed noticeable enhancement of density and radio-opacity in the third molar socket area, in comparison with the baseline image. Further, clinical examination showed significant reduction of periodontal pocketing and evidence of new bone formation.In conclusion, PRGF was very successful in stimulating bone regeneration and promote healing following dental extraction.

Thermal burn of palate caused by microwave heated cheese-pie: A case report

A female patient, 36-years-old, complained of bilateral palatal pain on the anatomical area of upper second molars. The painful condition of palatal mucosa erosion was observed. Palatal erosions or ulcerations may be caused by heated food cooked in microwave ovens. We present a case of a bilateral palatal burn caused by cheese-pie. Concluding, any food containing cheese, when heated in microwave oven, may cause palatal burn if eaten immediately.

A forensic aspect of age characteristics of dentine using transversal microradiography: a case report

BackgroundTranslucency of dentine is the result of occlusion of the corresponding dentinal tubules by a mineral substance which has a refractive index similar to that of the rest of the dentine.Case presentationThis case report describes the microradiographic features of an upper cadaveric canine. Transverse microradiograph is one of the methods assessing apical dentine translucency for various dental and medical reasons.ConclusionEstimation of age using teeth structures may be of primary value in forensic dentistry, especially when soft tissues are severely destructed.

One-stage multiple root canal treatment of adjacent teeth combined with surgical apicectomies may be preferred in patients with severe anxiety under local anaesthesia: a case report.

A female patient referred to the clinic for assessment of a unilateral painful swelling formation on the left anterior maxilla. Anxiety is a psychological condition commonly seen in dental practice. When this psychological alteration affects the patient severely, any dental operation may be found difficult under local anaesthesia. We report a case of one-stage management in a patient with periapical lesion and anxiety.