Vertical root fractures associated with endodontically treated teeth and less commonly in vital teeth represent one of the most difficult clinical problems to diagnose and treat. In as much as there are no specific symptoms, diagnosis can be difficult. Clinical detection of this condition by endodontists is becoming more frequent, where as it is rather underestimated by the general practitioners. Since, vertical root fractures almost exclusively involve endodontically treated teeth; it often becomes difficult to differentiate a tooth with this condition from an endodontically failed one or one with concomitant periodontal involvement. Also, a tooth diagnosed for vertical root fracture is usually extracted, though attempts to reunite fractured root have been done in various studies with varying success rates. Early detection of a fractured root and extraction of the tooth maintain the integrity of alveolar bone for placement of an implant. Cone beam computed tomography has been shown to be very accurate in this regard. This article focuses on the diagnostic and treatment strategies, and discusses about predisposing factors which can be useful in the prevention of vertical root fractures.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: The purpose of the present study was to comparatively evaluate the effect of presence of a 2 mm ferrule and different type of dowels on fracture resistance of mandibular premolars. Materials and Methods: Fifty uniradicular mandibular premolars were divided into five groups (n = 10). Ten teeth received no treatment (group I). Samples in group II & III were decoronated 2 mm above cemento-enamel junction and received custom cast dowel-core and fiber dowel-composite core respectively, with 2 mm ferrule. Samples in group IV & V were decoronated at CEJ and were restored using cast dowels and fiber dowel-composite cores, without any ferrule. The restored teeth received metal ceramic crowns and were mechanically loaded. The specimens were subjected to a static load, until fracture, to determine the fracture resistance and fracture mode. Results: The samples with 2 mm ferrule had a higher fracture resistance than non ferrule groups. Within non ferrule groups, there were no significant differences in the fracture resistance. Specimen restored with cast dowel had more incidence of non-repairable fracture. Conclusions: Presence of ferrule increased the fracture resistance of endodontically treated teeth. In case of absence of ferrule, fiber dowels had similar fracture resistance as that of cast dowels and showed increased incidence of repairable fracture.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Background and Aims: Extrusion of any debris during endodontic treatment may potentially cause post-operative complications such as flare-ups. The purpose of this in vitro study was to assess the amount of apically extruded debris during the root canal preparation using rotary and reciprocating nickel-titanium instrumentation systems. Materials and Methods: In this study, 60 human mandibular first premolars were randomly assigned to 3 groups (n = 20 teeth/group). The root canals were instrumented according to the manufacturers' instructions using the Reciprocating single-file system WaveOne^™ (Dentsply Maillefer, Ballaigues, Switzerland) and full-sequence rotary Hyflex CM^™ (Coltene Whaledent, Allstetten, Switzerland) and ProTaper^™ (Dentsply Maillefer, Ballaigues, Switzerland) instruments. The canals were then irrigated using bidistilled water. The debris that was extruded apically was collected in preweighed eppendorf tubes and assessed with an electronic balance and compared. Statistical Analysis Used: The debris extrusion was compared and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. Results: The WaveOne^™ and ProTaper^™ rotary instruments produced significantly more debris compared with Hyflex CM^™ rotary instruments (P < 0.05). Conclusions: Under the conditions of this study, all systems that were used resulted in extrusion of apical debris. Full-sequence rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Objectives: The objective of this in vitro study was to assess the effect of different chelating agents on the calcium loss and its subsequent effect on the microhardness of the root dentin. Materials and Methods: Ten single rooted lower premolars were selected. The teeth were decoronated and thick transverse sections of 2 mm were obtained from the coronal third of the root. Each section was then divided into four quarters, each part constituting a sample specimen from the same tooth for each group. The treatment groups were: Group 1 (Control): 5% Sodium hypochlorite (NaOCl) for 5 min + distilled water for 5 min; Group 2: 5% NaOCl for 5 min + 17% ethylenediaminetetraacetic acid (EDTA) for 5 min; Group 3: 5% NaOCl for 5 min + 2.25% Peracetic acid (PAA) for 5 min and Group 4: 5% NaOCl for 5 min + QMix for 5 min respectively. The calcium loss of the samples was evaluated using the Atomic Absorption Spectrophotometer followed by determination of their microhardness using Vickers Hardness Tester. Data was analyzed using one-way ANOVA, Post hoc Tukey test and Pearson correlation. Results: The maximum calcium loss and minimum microhardness was observed in Group 3 followed by Group 2, Group 4 and Group 1. There was a statistically significant difference between all the groups except between Groups 2 and 4. Conclusions: Irrigation with NaOCl + 2.25% PAA caused the maximum calcium loss from root dentin and reduced microhardness. A negative correlation existed between the calcium loss and reduction in the microhardness of root dentin.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Background: Early enamel lesions have a potential to re-mineralize and prevent caries progress. Aim: The aim of the following study is to determine the depth of penetration of low viscosity resin into artificially created enamel lesions. Materials and Methods: A sample of 20 sound premolars, indicated for orthodontic extraction, formed the study group. The teeth were coated with a nail varnish, leaving a window of 4 mm × 4 mm, on buccal surfaces of sound, intact enamel. Each tooth was subsequently immersed in demineralizing solution for 4 days to produce artificial enamel lesions. The demineralized area was then infiltrated with low viscosity resin (Icon Infiltrant, DMG, Hamburg, Germany) as per the manufacturer's instructions. All the restored teeth were then immersed in methylene blue dye for 24 h at 37°C. Teeth were then sectioned longitudinally through the lesion into two halves. The sections were observed under stereomicroscope at ×80 magnification and depth of penetration of the material was measured quantitatively using Motic software. Results: The maximum depth of penetration of the resin material was 6.06 ± 3.31 μm. Conclusions: Resin infiltration technique appears to be effective in sealing enamel lesions and has great potential for arresting white spot lesions.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Background and Aim: Periapical lesions often present differently on the radiograph resulting in a dilemma in the mind of the dentist to arrive at a final diagnosis. Although, histopathologic diagnosis has been used for confirmation of the true nature of periapical lesion, the concept of transformation of periapical granulomas containing epithelium without cystification into cyst remains controversial. The aim of this in vivo study was to evaluate the efficacy of conventional radiography and histopathology in differentiating periapical lesions in adjunct with immunohistochemical analysis. Materials and Method: Thirty patients having large periapical radiolucency that do not heal successfully with routine endodontic therapy in relation to either maxillary or mandibular anterior teeth were selected for the study. Intraoral periapical radiographs were obtained and provisional diagnosis of the apical areas were made. Endodontic surgery was performed to enable histopathogical investigation. The histopathological interpretation was done to arrive at a final diagnosis and selected questionable granulomas were subjected for cytokeratin (CK-14) stain. Results: The histopathological profile of lesions consisted of 66.66% periapical granulomas, 10% cysts, 6.67% abscess and 16.67% granulomas with cystic potential. The radiographic and histopathologic correlation was found in only 30% of these cases. Strong CK-14 expression was observed in all five cases of periapical granuloma with cystic potential. Conclusion: The radiographic diagnosis of periapical lesions remains inconclusive. Although histopathologic examination of periapical lesions gives true nature, the precise nature of subsets of periapical granulomas may be achieved with adjunct use of immunohistochemical markers.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: To evaluate bond strength between RMGI and composite using different adhesive systems and curing techniques. Materials and Methods: Sixty prepared samples of RMGI were randomly divided into six groups according to adhesive systems (total-etch, two-step self-etch and all-in-one) and curing techniques (co-curing and pre-curing). In co-curing technique, the adhesive systems were applied on uncured RMGI samples and co-cured together. In the pre-curing technique, before application of adhesive systems, the RMGI samples were cured. Composite layers were applied and shear bond strength was measured. Two samples of each group were evaluated by SEM. Failure mode was determined by streomicroscope. Results: Both curing methods and adhesive systems had significant effect on bond strength (P-value < 0.05). There was an interaction between two factors (P-value <0.05). Both self-etch adhesives had significantly higher shear bond strength than the total-etch adhesive (P-value <0.05). The co-curing technique improved the bond strength in self-etch adhesives, but decreased the bond strength in total-etch adhesive (P-value<0.05). Conclusion: The application of self-etch adhesive systems and co-curing technique can improve the bond strength between the RMGI and composite.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Introduction: Intraoral local anesthesia is essential for delivering dental care. Needless devices have been developed to provide anesthesia without injections. Little controlled research is available on its use in dental restorative procedures in adult patients. The aims of this study were to compare adult patients acceptability and preference for needleless jet injection with classical local infiltration as well as to evaluate the efficacy of the needleless anesthesia. Materials and Methods: Twenty non fearful adults with no previous experience of dental anesthesia were studied using split-mouth design. The first procedure was performed with classical needle infiltration anesthesia. The same amount of anesthetic solution was administered using MADA jet needleless device in a second session one week later, during which a second dental restorative procedure was performed. Patients acceptance was assessed using Universal pain assessment tool while effectiveness was recorded using soft tissue anesthesia and pulpal anesthesia. Patients reported their preference for the anesthetic method at the third visit. The data was evaluated using chi square test and student's t-test. Results: Pressure anesthesia was more accepted and preferred by 70% of the patients than traditional needle anesthesia (20%). Both needle and pressure anesthesia was equally effective for carrying out the dental procedures. Conclusion: Patients experienced significantly less pain and fear (p<0.01) during anesthetic procedure with pressure anesthesia. However, for more invasive procedures needle anesthesia will be more effective.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aims: This study compared the canal curvature modifications after instrumentation with One Shape (Micro Mega) rotary file and Wave One primary reciprocating file (Dentsply Maillefer, Ballaigues, Switzerland). Materials and Methods: Thirty International Organization for Standardization 15, 0.02 taper, Endo Training Blocks (Dentsply Maillefer) were used. In all specimens working length (WL) was established at the reference point 0. Glide path was achieved with Path-File 1, 2 and 3 (Dentsply Maillefer) at the WL. Group 1 were shaped with One Shape file and group 2 with Wave One files. Pre and post-digital images were superimposed, processed with Corel draw Graphic Suite X5 (Corel Corporation, Ottawa, Canada), Adobe Photoshop CS3 (Adobe Systems Inc., San Jose, CA) and Solid works student Edition software (Dassault Systems Solid Works Corp, S.A., Velizy, France). Statistical Analysis: It was done with mean, standard deviation, one-way ANOVA, (P < 0.05) t-test and Karl Pearson's correlation coefficient. Results: Mean was more for Wave One compared with One Shape. One-way ANOVA and t-test showed a significant difference between One Shape and Wave One at 5% level of significance (P < 0.05). Conclusions: Canals prepared with Wave One file preserved canal shape, respected the anatomical shape of J-shaped canal and produced a continuously tapered funnel.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: The aim of the following study is to compare the evaluation of different irrigation activation system-F-File, CanalBrush (CB) and EndoActivator (EA) in removing smear layer from root canal. Materials and Methods: Root canals of eighty single rooted decoronated premolar teeth were instrumented using crown-down technique and then equally divided into four groups on basis of irrigation activation methods used: Without irrigation - control group, irrigation with F-File, CB, EA into Group I, II, III respectively. Samples were then longitudinally sectioned and examined under scanning electron microscope by three qualified observers using score from 1 to 4. Data was analyzed using Statistical Package for Social Sciences (SPSS), version 15.0 (SPSS Inc., Chicago IL) at significance level of P ≤ 0.05. Results: Minimum mean score was observed in Group II at coronal, apical locations. Group III had minimum score at middle third. Groups difference in score were found to be significant statistically for all three locations as well as for overall assessment (P < 0.001). Conclusion: CB remove smear layer more efficiently from the root canal than F-File and EA in coronal and apical region.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Objective: The anti-microbial efficacy of 2.5% sodium hypochlorite (SHC) and 0.2% chlorhexidine gluconate were compared with an experimental irrigant formulated from the Neem tree, Azadirachta indica A. Juss. Materials and Methods: A sample of 36 single rooted anterior teeth with periapical radiolucency and absence of response to vitality tests that required root canal treatment were selected for this study. The test irrigants and their combinations were assigned to five different groups and saline served as the control. Access cavities were prepared using an aseptic technique and samples collected for both anaerobic culture and Gram stained smears, followed by irrigation and sample collection again. The number of organisms were expressed in colony forming units/ml after 72 h of incubation; the smears were analyzed for their microbial loads and tissue clearance and assessed as per defined criteria. Results: Our results found the maximum reduction in microbial loads, when analyzed by culture method, with a combination of SHC and the experimental neem irrigant. Maximum tissue clearance on the Gram Stained smears was also found with the same combination. Conclusion: Neem irrigant has anti-microbial efficacy and can be considered for endodontic use.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Objective: The objective of this study is to determine the best ferrule configuration of endodontically treated teeth. Materials and Methods: A total of 40 freshly extracted maxillary central incisors were collected. Teeth were allocated into following four groups of each having 10 teeth. Group 1 teeth restored with crowns (CRN), Group 2 endodontically treated teeth restored with crowns (RCT and CRN), Group 3 endodontically treated teeth restored with cast dowel cores and crowns incorporating uniform 2 mm ferrule (2 FRL), Group 4 endodontically treated teeth restored with cast dowel cores and crowns incorporating uniform 1 mm ferrule (1 FRL). Crown preparation was performed with varying ferrule heights, crowns were cemented with resin modified glass ionomer cement and were kept in 100% humidity for 3 days, all specimens were loaded to failure in a universal testing machine at 0.5 mm/min. Results were obtained in the form of kilo Newton and Newton. Result: The statistical analysis applied was an analysis of variance to detect the presence of group differences. Pair wise comparisons between the groups were analyzed with the Tukey Kramer significant difference test for multiple comparisons. Conclusion: Ferrule had a significant role in the fracture resistance of custom cast post core restored teeth. Endodontically treated maxillary central incisors with a uniform 2 mm ferrule were more fracture resistant than those with a uniform 1 mm ferrule.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aims: The aim of the following study was to evaluate the percentage and average depth of epiphany sealer penetration into dentinal tubules among the coronal, middle and apical thirds of the root using the confocal laser scanning microscopy (CLSM). Materials and Methods: A total of 10 maxillary central incisors were prepared and obturated with Resilon-Epiphany system. Sealer was mixed with fluorescent rhodamine B isothiyocyanate dye for visibility under confocal microscope. Teeth were cross-sectioned into coronal, middle and apical sections-2 mm thick. Sections were observed under CLSM. Images were analyzed for percentage and average depth of sealer penetration into dentinal tubules using the lasso tool in Adobe Photoshop CS3 (Adobe systems incorporated, San jose, CA) and laser scanning microscopy (LSM 5) image analyzer. Statistical Analysis Used: One-way analysis of variance with Student Neuman Keuls post hoc tests, Kruskal-Wallis test and Wilcoxon signed-rank post hoc tests. Results: The results showed that a higher percentage of sealer penetration in coronal section-89.23%, followed by middle section-84.19% and the apical section-64.9%. Average depth of sealer penetration for coronal section was 526.02 μm, middle-385.26 μm and apical-193.49 μm. Conclusions: Study concluded that there was higher epiphany sealer penetration seen in coronal followed by middle and least at apical third of the roots.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: The aim of this study was to determine the occurrence of pulp stones in a group of the population of Andhra Pradesh. This study also aims to determine the association of pulp stones in different sexes, tooth type, dental arches and sides and with systemic diseases. Materials and Methods: A total of 4449 teeth of 2000 patients were examined, comprising of patients with C.V.S. disorders; Type II diabetes mellitus and gastritis were examined. Patients were selected from the radiology department who came for diagnostic radiograph of posterior teeth. The presence or absences of pulp stones were recorded. Statistical Analysis Used: Statistical analysis of the data was done using the statistical package for the social sciences (SPSS 15.0-SPSS Inc., 233 South Waker Drive, 11 ^th floor, Chicago, IL 60606-6412.) using Chi-square analysis. Differences were considered as significant when P ≤ 0.05. Results: Pulp stones were found in 799 (17.9%) of 4449 teeth detected. Significantly, higher numbers of pulp stones were recorded in patients with systemic diseases. The occurrences of pulp stones were significantly higher in maxillary first and second molars. No significant difference was found between sexes and sides. Conclusions: Positive correlation was found between systemic disorder and occurrence of pulp stones.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

It is important to assess the root canal morphology and its variations before initiating the endodontic procedure. This is because the inability to clean the complete root canal system forms the seat for the persistent infection which ultimately leads to endodontic treatment failure. This case reports the use of dental operating microscope for the successful endodontic management of a two rooted and three canaled mandibular canine with the fractured instrument in the middle canal of a 38-year-old healthy Asian woman. This case report highlights the need to use the dental operating microscope and ultrasonics in locating the elusive canal orifices. It is important to note the internal and external root canal morphological variations before starting the endodontic treatment without any pre-operative assumptions about the usual anatomy of the toot.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]

Bernard-Soulier syndrome is a rare inherited disorder with giant platelets, thrombocytopenia and a prolonged bleeding time. These abnormalities are caused by genetic defects of the glycoprotein Ib/IX/V complex that constitutes the von Willebrand factor receptor on the platelet surface. We are documenting a 30-year-old female patient reported with a chief complaint of swelling in relation to right maxillary canine for 5 days. The primary treatment remains platelet transfusion. Root canal treatment was performed following platelet rich plasma transfusion. As the tooth was necrotic and had a periapical pathology post-operative bleeding was absent. The root canal treatment was uneventful and the patient was asymptomatic. Optimum oral hygiene practices were emphasized to avoid dental diseases.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: The aim of this study is to address the cause of persistent infection of root cementum by Enterococcus faecalis. Materials and Methods: A sample of 60 human single-rooted teeth were divided into three groups. Group I (control group) had no access opening and one-third of the apical root cementum was sealed using varnish. Group II had no preparation of teeth samples. In group III, apical root cementum was exposed to organic acid and roughened using diamond point to mimic apical resorption. After access opening in groups II and III, all teeth samples were sterilized using gamma irradiation (25 kGy). E. faecalis broth was placed in the root canal and apical one-third of the tooth was immersed in the broth for 8 weeks with alternate day refreshment followed by biomechanical preparation, obturation and coronal seal. Apical one-third of all teeth samples were again immersed in the broth for 8 weeks with alternate day refreshment to mimic secondary infection. The samples were observed under a confocal microscope after splitting the teeth into two halves. Results: E. faecalis penetrated 160 μm deep into the root cementum in group III samples and only showed adhesion in group II samples. Conclusion: Penetration and survival of E. faecalis deep inside the cementum in extreme conditions could be the reason for persistent infection.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]  [PubMed]

Aim: This study evaluated the effect of filler existence in self-etch adhesive resin on the marginal leakage of a class V restoration. Materials and Methods: Class V cavities were prepared and restored with a resin composite on the buccal surfaces of 48 premolars lined with unfilled or filled adhesives (n = 24). After thermo cycling, teeth in each group were divided to two subgroups (n = 12), specimens of the first subgroup were incubated for 24 h in distilled water at 37°C, and for the second group three months in the same condition. Specimens were placed in 50% silver nitrate for 24 h at 37°C, and then were cut buccolingually 1 mm thick. Dye penetration was measured using a stereomicroscope and scaled from 0 to 5 in a blind method. SEM images were made to evaluate the dentin-adhesive interfaces. Collected data were analyzed using the nonparametric Kruskal-Wallis and Mann-Whitney U-tests at a significant level of P<0.05. Results: There was no significant difference between microleakage of filled and unfilled adhesive at 24 h and 3 months (P<0.05). There was a significant difference in cervical microleakage between 24 h and 3 months, which was independ on filler load of the adhesive (P<0.001). In contrast, there was no significant difference in occlusal microleakage between 24 h and 3 months and the cervical microleakage was significantly higher than occlusal microleakage after 3 months. SEM images reveald that unfilled adhesive infiltrate slightly better than filled adhesive. Conclusion: The application of filler particles in a self etch adhesive system had no influence on marginal leakage at both the enamel and dentin margins. While the unfilled adhesive infiltrate better than the filled adhesive, its long term performance is not promising.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]  [PubMed]

Aims: The aim of the following study is to evaluate the change in laser fluorescence (LF) values for extracted teeth stored in different solutions over 1 year period, to give cut-off values for different storage media at different time intervals to get them at par with the in vivo conditions and to see which medium gives best results with the least change in LF values and while enhancing the validity of DIAGNOdent in research. Materials and Methods: Ninety extracted teeth selected, from a pool of frozen teeth, were divided into nine groups of 10 each. Specimens in Groups 1-8 were stored in 1% chloramine, 10% formalin, 10% buffered formalin, 0.02% thymol, 0.12% chlorhexidine, 3% sodium hypochlorite, a commercially available saliva substitute-Wet Mouth (ICPA Pharmaceuticals) and normal saline respectively at 4°C. The last group was stored under frozen condition at −20°C without contact with any storage solution. DIAGNOdent was used to measure the change the LF values at day 30, 45, 60, 160 and 365. Statistical Analysis Used: The mean change in LF values in different storage mediums at different time intervals were compared using two-way ANOVA. Results: At the end of 1 year, significant decrease in fluorescence (P < 0.05) was observed in Groups 1-8. Maximum drop in LF values occurred between day 1 and 30. Group 9 (frozen specimens) did not significantly change their fluorescence response. Conclusions: An inevitable change in LF takes place due to various storage media commonly used in dental research at different time intervals. The values obtained from our study can remove the bias caused by the storage media and the values of LF thus obtained can hence be conveniently extrapolated to the in vivo condition.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]  [PubMed]

Aim: The aim of the present study is to evaluate the residual root thickness in mesiolingual (ML) canals of mandibular molars after pre-flaring using different sequences of Gates-Glidden (GG) drills. Materials and Methods: Computed tomography (CT) scans of the ML canals of 60 mandibular first molars were provided from areas within 1, 2, 3 and 4 mm of the furcation area and minimum initial root thickness (MIRT) of concave areas was measured at each level. The samples were divided into two groups (G1 and G2) which were prepared by the step-back and crown-down techniques, respectively. In both groups, anti-curvature filing was used. On secondary CT images of the samples in the same position, the minimum residual root thickness (MRRT) and the amount of removed dentin were analyzed by t-test and ANOVA. Results: There was no significant difference for MIRT between the two groups. The MRRT was greater in the G2 group in all the sections, with no significant difference between them. The average of MRRT was not <0.5 mm in any of the groups or sections. Conclusion: Based on the results of this study when the appropriate root thickness is present initially, GG drills used in any sequence may be suitable, safe and cost effective for pre-flaring of mesial canals of mandibular first molars with preserving the root thickness of furcation areas.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]  [PubMed]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]  [PubMed]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]  [PubMed]