Efficacy of Er,Cr:YSGG Laser with Different Output Powers on Removing Smear Layer After Retreatment of Two Different Obturation Techniques.

Objective: This study was designed to evaluate the effects of an Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet (Er,Cr:YSGG) laser on removing the filling residues and smear layer (SL) after retreatment using rotary files. Background: Er,Cr:YSGG laser has been proposed as an additional protocol to improve root canal cleaning and removal of the filling remnants. Methods: Eighty-four mandibular premolars were divided into six groups (n = 14). Groups 1, 2, and 3 were obturated using a cold lateral compaction technique, and groups 4, 5, and 6 were obturated using a thermoplasticized injectable technique. The retreatment procedures were performed in all of the groups using a rotary system before applying Er,Cr:YSGG laser at 1.5 W for groups 2 and 5, and at 3.0 W for groups 3 and 6. Then, the teeth were split longitudinally into two halves and observed under a stereomicroscope and a scanning electron microscope. The SL and residual filling materials were evaluated at the coronal, middle, and apical thirds of the root canal. The data were statistically analyzed using three-way analysis of variance and Tukey tests. Results: The 3.0 W Er,Cr:YSGG laser was significantly more effective in removing SL than the other retreatment procedures in the coronal and middle thirds, but there was no significant difference in the apical third (p > 0.05). However, carbonization was observed in some of the specimens in the 3.0 W laser groups. Conclusions: None of the retreatment procedures completely removed the filling remnants from the root canal. However, the additional use of lasers improved the canal cleaning after retreatment.

Protective effect of alpha-lipoic acid against apical periodontitis-induced cardiac injury in rats.

This study was designed to assess the possible protective effect of alpha-lipoic acid (ALA) on apical periodontitis (AP)-induced cardiac injury. Wistar albino rats were randomized into four groups: control; ALA; AP; and ALA + AP. Rats of the control and ALA groups were not endodontically treated, but saline and ALA (100 mg kg-1 ) were administered. In rats of the AP and ALA + AP groups, the pulp chambers of mandibular first molar teeth were exposed and left open for 30 d to induce AP. Saline and ALA (100 mg kg-1 ) were administered intraperitoneally every 24 h during the experiment. At the end of the experiment, the rats were killed. Establishment of AP was verified by radiographic and histopathological evaluation. Serum alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatine kinase (CK), and superoxide dismutase (SOD) activities were determined using an automated biochemical analyzer, and the structural cardiac injury was assessed pathologically. Serum ALP, LDH, and CK activities were elevated, and SOD activities were decreased, in the AP group. The changed enzyme activities were significantly normalized by treatment with ALA. We conclude that ALA administration alleviated the AP-induced heart injury and improved cardiac structure and function, and therefore this agent may be of potential therapeutic value in protecting cardiac tissue from systemic injury caused by AP.

Push-Out Bond Strength and SEM Evaluation in Roots Filled with Two Different Techniques Using New and Conventional Sealers.

The aim of this study was to evaluate the influence of calcium-silicate-based sealer (Endosequence-BC-Sealer) in roots, filled with thermo-plasticized injectable technique aided by Calamus-Flow-Delivery-System, on bond strength to radicular dentin, in comparison with conventional epoxy-resin-based sealer (AH-Plus) along with cold-lateral-compaction technique. Root canals of mandibular-premolar teeth (n = 80) were instrumented using Protaper Universal rotary files and were randomly divided into four experimental groups (n = 20) as follows: (1) AH-Plus + cold-lateral-compaction technique; (2) Endosequence-BC-Sealer + cold-lateral-compaction technique; (3) AH-Plus + thermo-plasticized injectable technique; and (4) Endosequence-BC-Sealer + thermo-plasticized injectable technique. Horizontal disc shaped samples from each group (n = 60/group) were obtained and push-out bond strength testing was performed at a cross-head speed of 0.5 mm/min. Data were analyzed statistically using nonparametric Kruskal-Wallis analysis and Mann-Whitney test (p < 0.001). The statistical analysis revealed a significant difference amongst the groups (p < 0.001). The highest bond strength values were found in group 1 compared with all the other experimental groups (p < 0.001), whereas the lowest bond strength values were found in group 4 (p < 0.001). It was concluded that thermo-plasticized injectable technique with Calamus-Flow-Delivery-System lowered the bond strengths of the sealers, especially Endosequence-BC-Sealer. Therefore, this technique is not recommended to calcium-silicate-based sealers. Further studies are needed to confirm the findings of this study.

Determination of the Minimum Inhibitory Concentrations of Alexidine and Chlorhexidine Against Enterococcus faecalis and Candida albicans: An In Vitro Study.

INTRODUCTION: The root canal system must be mechanically instrumented and chemically cleaned using various antimicrobial irrigants in a sequential manner or in combination for the elimination of necrotic pulp tissue and reducing the number of root canal bacteria. For this reason, new methods and materials are continuously being developed to achieve the objectives of endodontic treatment. MATERIALS AND METHODS: E. faecalis (ATCC 29212) and C. albicans (ATCC 90028) standard strains were used for this study. Colonies of E. faecalis and C. albicans were harvested from the agar plates and suspended in 4 mL of phosphate buffered saline (PBS). Microorganisms were diluted to obtain a suspension of approximately 108 colony-forming units/mL (CFU/mL) in sterile PBS using McFarland standard tubes no. 0.5. RESULTS: After a two-minute contact time, all alexidine (ALX) concentrations used in this study eradicated all E. faecalis strains, while chlorhexidine (CHX) didn't kill 100% of E. faecalis at 0.25% and lower concentrations even after a five-minute contact time. ALX also eradicated C. albicans at all concentrations even after a one-minute contact time. CHX showed antifungal activity against C. albicans at all concentrations higher than 0.031% after a one-minute contact time. CONCLUSION: A 0.0156% concentration of ALX can be a good alternative to CHX as an irrigation solution in endodontic treatment when used for one minute against E. faecalis and C. albicans.

Cone beam CT evaluation of mandibular molar root canal morphology in a Turkish Cypriot population.

OBJECTIVES: Microorganisms in untreated or overlooked root canals can cause endodontic failure or infection and inflammation. Therefore, clinicians should familiarize themselves with patient's root canal anatomy and morphology. The objective of this retrospective study was to analyze and characterize mandibular root canal morphology using cone beam computed tomography (CBCT) in a Turkish Cypriot population. MATERIALS AND METHODS: This cross-sectional study consisted of retrospective evaluation of CBCT scans from 272 adult patients (aged 16-80 years). The number of roots and canals and the canal configuration in each root were evaluated using Vertucci's classification. The incidence of additional roots and of C-shaped canals in the mandibular first and second molars was also noted. Pearson chi-square tests were performed to analyze canal configurations, laterality, and gender (p ≤ 0.05). RESULTS: For the female and male patients, 94.5 and 94.4 % of the mandibular first and 96.7 and 97.2 % of the mandibular second molars had two roots, respectively. In females, 4.4 % of mandibular first molars had three roots versus 2.7 % of mandibular first molars in male patients. Type IV was the most prevalent canal configuration regardless of the gender (female 61.3 % and male 64.2 %) in the mesial roots. No statistically significant differences according to gender or laterality were found in the incidence of additional canals for either maxillary first or second molars. CONCLUSIONS: Type IV was the most prevalent canal configuration of both the mandibular first and second molar teeth. There was a low prevalence of three-rooted mandibular molars in this particular population. CLINICAL RELEVANCE: The current study is the first of its kind to include a Turkish Cypriot population and, thus, provides baseline data for these patients regarding appropriate root canal treatments.

Cone-beam CT evaluation of root canal morphology of maxillary and mandibular premolars in a Turkish Cypriot population.

OBJECTIVES: Because of economic and political issues, Turkish Cypriots have been emigrating from Cyprus since the 1920s, especially to the United Kingdom, other European countries and Australia. Recently, according to the UK House of Commons, Home Affairs Committee, ~300,000 Cypriot Turks were living in the United Kingdom. However, this ethnic population residing in the United Kingdom has been insufficiently analysed. Although many Turkish Cypriots have been living abroad, little is known about the dental characteristics of this group. Premolar teeth, especially maxillary premolars, pose great challenges in endodontic treatment because of the number of roots and canals, and the variation in the configurations of the pulp cavity. Thus, it was considered valuable to determine the morphological characteristic of premolar teeth in a Turkish Cypriot population to aid clinicians in performing endodontic treatment in this ethnic population. MATERIALS AND METHODS: The sample for this cross-sectional study consisted of a retrospective evaluation of cone-beam CT scans of 263 adult patients (age range 16-80 years). The number of roots and their morphology, the number of canals per root and the canal configuration were examined. The root canal configurations were also classified according to the scheme of Vertucci in the maxillary and mandibular premolar teeth. Pearson's χ2-test was performed among canal configurations, sides and gender (P⩽0.05). RESULTS: In the present study, most root canal configurations were type IV (76.8%) and type I (49.4%) in the maxillary first and second premolars, respectively, whereas most root canal configurations were type I (93%) in both mandibular first and second premolars. In total, four (0.9%) teeth in the maxillary first premolars and two (0.4%) teeth in the maxillary second molar premolars had three roots. CONCLUSIONS: This is the first population-based study to focus solely on Turkish Cypriots' root canal anatomy. Our findings will be valuable for dental professionals who treat many Turkish Cypriot patients, in the United Kingdom, Australia and other countries.

CBCT evaluation of multiple idiopathic internal resorptions in permanent molars: case report.

BACKGROUND: Internal inflammatory root resorption is a rare condition in permanent teeth, which requires the presence of necrotic and infected pulp tissue within the coronal portion of the root canal system as well as inflamed pulp tissue apical to the resorptive defect. The aetiology of internal root resorption is not completely understandable, trauma and chronic pulpitis are considered the main risk factors. CASE PRESENTATION: We report a rare case of the multiple idiopathic resorption in the permanent maxillary and mandibular molars in a healthy 33-year-old female patient. In addition to clinical examination the patient was imaged using conventional radiography techniques and cone beam computed tomography (CBCT).The patient had recurrent throbbing pain in her # 46. The radiographic examination including "panoramic radiography and CBCT" revealed that radiographic evidence of internal resorption in #37 #36 #35 #34 #33 #47 #46 #45 #44 #43 #16 #15 #14 #13 and also including in unerupted #17, #26, #27, #28 teeth. The definitive diagnosis was made with the histopathological examination of the extracted tooth. CONCLUSIONS: Internal root resorption is a rare clinical process that should be examined using different radiographic modalities. CBCT seems to be useful in evaluation of the lesions with superior diagnostic performance.

Cone-beam computed tomography analysis of the vestibular surgical pathway to the palatine root of the maxillary first molar.

OBJECTIVE: The aim of this study was to evaluate the anatomical distance between apices of the palatine root of the maxillary first molars to the buccal bone plate to identify the vestibular surgical pathway in a Turkish adult population using cone-beam computed tomography (CBCT) images. METHODS: CBCT scans of 107 (48 male and 59 female) patients were retrospectively analyzed. The overall mean age was 38.6 years. The distance between the vestibular cortex and vestibular side of the palatine root was measured for 192 maxillary first molars both on axial images parallel to the palatal plane and on reformatted cross-sectional images. A Pearson's chi square test and Mann-Whitney U-test were performed to evaluate differences among age, localization, and measurements. Differences were considered statistically significant at P<.05. RESULTS: The mean distance between the buccal cortex and the buccal side of the palatine root of the superior first molar in both male and female patients was 10.13 and 9.70 mm, respectively. The incidence of interposition of the lateral recess of the maxillary sinus between the roots was 42.2% and 49% in men and women, respectively. Statistically significant sex-related differences were found in the vestibular surgical pathway (P<.05). CONCLUSIONS: For precise planning of endodontic surgery, it is crucial to determine the exact dimensions and location of the periapical lesion, as well as its relationship with the roots and other neighboring anatomical structures. CBCT can be a powerful tool for the evaluation of surgical cases in three dimensions with less ionizing radiation and better avoidance of complications during surgery.

Influence of the quality of endodontic treatment and coronal restorations on the prevalence of apical periodontitis in a Turkish Cypriot population.

OBJECTIVES: The aim of this study was to assess the prevalence of periapical lesions in root canal-treated teeth in a Turkish Cypriote population and to investigate the influence of the quality of root canal fillings and coronal restorations on the prevalence of periapical lesions. SUBJECTS AND METHODS: The sample for this cross-sectional study consisted of 1,006 adult patients seeking routine dental care. Patients who had received dental care in the last 2 years were excluded. Radiographs of 2,200 root canal-treated teeth were evaluated. The teeth were grouped according to the radiographic quality of the root canal filling and the coronal restoration. Periapical status was assessed using periapical index (PAI) scores. RESULTS: Of the 2,200 root canal-treated teeth, 1,364 (62%) had apical periodontitis as compared with 1,364 (5.5%) of the total sample. Root-filled teeth classified as adequately treated had apical periodontitis in 223 (26.6%) cases compared with 1,192 (87.7%) in teeth classified as inadequately root filled. PAI 1 scores of adequate root canal treatment were significantly higher than in inadequate root canal treatment, regardless of the quality or presence of coronal restorations (p < 0.01). CONCLUSION: Our findings showed a high prevalence of periapical pathology with or without endodontic treatment and poor technical standard of both root fillings and coronal restorations of root-treated teeth. Hence, we suggest the need for better education for dental health providers so that they can perform better root canal treatments and coronal restorations.

Periorbital emphysema during dental treatment: a case report.

Periorbital emphysema is a rare complication of dental treatment. To date, there is only 1 case of periorbital emphysema during dental treatment reported in the literature. Etiologies and guidelines for the prevention of this complication during dental treatment were outlined and a rare case was presented.

Low-level laser therapy of dentin hypersensitivity: a short-term clinical trial.

The aim of this study was to evaluate low-level laser therapy in cervical dentin hypersensitivity. A randomized controlled clinical trial was conducted with a total of 64 teeth. Dentin desensitizer and diode laser were applied on the cervical dentin surfaces. Distilled water and placebo laser was used as the placebo groups. The irradiance used was 4 J/cm(2) per treatment site. The baseline measurement of hypersensitivity was made by using visual analog scale (VAS). Twenty-four hours and 7 days after the application of desensitizer, diode laser and placebo groups, a new VAS analysis was conducted for the patients' sensitivity level. The mean pain scores of placebo groups were significantly higher than the desensitizer's and diode laser's mean scores (ANOVA, p < 0.05). The VAS analysis revealed a significant decrease in dentin hypersensitivity in 7 days with the use of the desensitizer and low-level laser therapy and no statistically significant difference was observed between these two treatments (p > 0.05). Although low-level laser and glutaraldehyde containing desensitizer present distinct modes of action, experimental agents caused a significant reduction of dentin hypersensitivity without showing secondary effects, not irritating the pulp or causing pain, not discoloring or staining the teeth, and not irritating the soft tissues at least for a period of 1 week with no drawbacks regarding handling and/or ease of application. Low-level laser therapy and desensitizer application had displayed similar effectiveness in reducing moderate dentin hypersensitivity.

Cone-beam computed tomographic evaluation of spontaneously healed root fracture.

INTRODUCTION: Dental trauma can lead to injuries in teeth and their supporting structures, which occurs most commonly in young patients and varies in severity from enamel fractures to avulsions. Root fractures are relatively uncommon among dental traumas, mostly affecting the permanent dentition. It has been reported that root fractures can undergo healing, whereas pulp necrosis can also occur. METHODS: In this report, we present a case of the utilization of cone-beam computed tomography (CBCT) in the detection of possible cervical or internal resorption secondary to a mid-horizontal fracture in a 36-year-old male patient. The fractured teeth spontaneously healed and were diagnosed radiographically after 28 years. Initially, conventional radiographs showed fractured fragments with radiolucent lines. Because of possible invasive cervical resorption and doubt over internal resorption in the conventional images, it was decided to examine the teeth with cone-beam computed tomography with three-dimensional reconstructions. RESULTS: The images clearly showed the displaced fragments of the root fracture. Despite the appearance in the conventional radiograph, no evidence of cervical or internal resorption was detected in the teeth other than the healed root fracture. CONCLUSION: It was concluded that CBCT images should be obtained for root fractures, especially those in which cervical or internal resorption is suspected from routine conventional radiographs.

Use of mineral trioxide aggregate in the treatment of invasive cervical resorption: a case report.

INTRODUCTION: Guided tissue regeneration (GTR) is a successful treatment procedure of periodontal reconstructive surgery. Adverse effects can be observed after GTR procedure, but external root resorption is rarely reported at clinical studies. Invasive cervical resorption is a clinical term used to describe a relatively uncommon, insidious, and often aggressive form of external root resorption. METHODS: The present case demonstrates an invasive cervical resorption that is a potential late complication of GTR in a maxillary canine of a 59-year-old male patient. After the surgical intervention and root canal treatment, the resorption was subsequently sealed with mineral trioxide aggregate. RESULTS: The 1-year follow-up demonstrates no pathologic changes on clinical and radiographic examination. CONCLUSIONS: This case report presents a treatment strategy that might improve the healing outcomes for patients with invasive cervical resorption.

Shear bond strengths of three different resin luting cements to bovine teeth.

This study evaluated the shear bond strengths of dentin/porcelain and enamel/ porcelain specimens bonded with three different dual-cure cements. The specimens were prepared using the heat-pressed ceramic technique. Three different dual-cure cements were used to bond samples to previously prepared bovine enamel and dentin surfaces. The specimens were thermocycled and tested in shear until failure. The shearbond data was subjected to one-way ANOVA, followed by Duncan's multiple range test at a significance level of p < 0.05. The shear bond strengths of Variolink II were significantly higher than those of Rely-X ARC and Panavia F for enamel and dentin (p < 0.05). Bond strenghts in enamel were higher than those of dentin in all materials (p < 0.05).

Effect of cavity disinfectants on the sealing ability of nonrinsing dentin-bonding resins.

OBJECTIVES: The purpose of this study was to determine the effect of three cavity disinfectants (chlorhexidine gluconate-based, Consepsis; benzalkonium chlorite-based, Tubulicid red; iodine-potassium iodide/copper sulphate-based, Ora-5) on the microleakage of nonrinsing dentin-bonding systems, Clearfil SE Bond and Prompt L-Pop. METHOD AND MATERIALS: Class V cavity preparations were placed on the buccal and lingual surfaces of extracted molars with occlusal margins at the enamel and gingival margins in cementum. In the experimental groups, cavities were treated with combinations of one of the three cavity disinfectants with either Clearfil SE Bond or Prompt L-Pop. The preparations without disinfectant application were used as the negative controls for each adhesive system, and the cavities in which neither disinfectant nor dentin-bonding resin were applied, served as the positive controls. After the cavity preparations were restored with resin composite, specimens were thermocycled, stained, and sectioned to evaluate dye penetration. The tooth-resin composite interface of the sectioned specimens was examined under scanning electron microscopy. RESULTS: Consepsis and Tubulicid red did not significantly affect the sealing ability of Clearfil SE Bond and Prompt L-Pop. Ora-5 exhibited gap formations at the tooth-resin composite interface and produced significantly higher microleakage when used with these bonding systems. CONCLUSION: Consepsis and Tubulicid red can be used as cavity disinfectants with Clearfil SE Bond and Prompt L-Pop without affecting their sealing abilities. However, Ora-5 is not an appropriate disinfectant to use with these bonding systems.