Incidence Of Dentinal Defects Research Articles

A Digital Microscopic Inspection of Dentinal Defects after Using Endodontic Retreatment Files.

Aim The study aimed at evaluating the incidence of dentinal defects after root canal retreatment with ProTaper Universal retreatment (PTUR) and XP-endo Shaper and Finisher R (XP). Materials and Methods Sixty extracted single-rooted human premolars were selected and divided into 4 groups of 15 teeth each. In the negative control group, the teeth were left unprepared. In the positive control group, the teeth were prepared with ProTaper Next and obturated with no further retreatment. In the PTUR and XP groups, the teeth were prepared and obturated followed by removal of the filling material at body temperature using PTUR and XP instruments, respectively. The roots were then sectioned at 3, 6, and 9 mm from the apex and observed under a digital microscope to detect defects. Results PTUR group showed significantly higher (p value <0.05) incidence of defects than the other groups. Comparison of no defects versus defects between groups in different areas of root canals demonstrated significant difference among the groups in the apical and cervical regions. Conclusion Within the limitations of the present study, PTUR files created significantly more dentinal defects than XP files, with most of those defects at the cervical and apical areas of the root canals.

Comparison of the Cleaning Effectiveness and Incidence of Dentinal Defects after Biomechanical Preparation Using Different Ni Ti Rotary Instruments in Root Canals

Purpose: This study was directed to evaluate the cleaning effectiveness& the dentinal defects incidence after preparation with different Ni-Ti rotary instruments in permanent molar root canals. Materials and Methods: A 60 human permanent lower first molars were used in this study. According to the Ni-Ti rotary system used in canal instrumentation, specimens were divided into 3 main groups (n=20) (One Shape, HyFlex EDM and XP-Endo Shaper). Each system was used as the suggested settings by manufacture. Each group was received Copious irrigation with 2.6% NaOCl was performed after the use of each file and finally with combination of 17% EDTA and 2.6% NaOCl. Then specimens were washed with distilled water. Each main group was divided into two subgroups (A &B) (n=10) according to evaluation methods: Subgroup A: The cleaning effectiveness (Scanning electron microscopic (SEM) evaluation). Subgroup B: The incidence of dentinal defects (Steriomicroscope evaluation). Results: Regarding to cleaning effectiveness, highest mean and standard deviation values were recorded for HF system while lowest mean value was recorded for XP system. Regarding to dentinal defects, the highest mean and standard deviation values were recorded for OS system, while the lowest mean value was recorded for XP system. Conclusions: The results of the present study showing that: XP-Endo Shaper file gives promising better results in cleaning ability with minimal incidence of dentinal defects found in root dentin.

A Stereomicroscopic Analysis of Dentinal Micro Cracks after Root Canal Preparation Using Four Different Rotary Instruments

A variety of single-engine driven files and kinematics have been introduced to improve the clinical performance of NiTi rotary files. The purpose of this in vitro study was to measure and compare the incidence of dentinal defects after root canal preparation with different single file systems.

The effects of canal preparation by different NiTi rotary instruments and reciprocating WaveOne file on the incidence of dentinal defects

The purpose of this study was to compare dentinal defect formation while usinghand files (HFs), two brands of nickel-titanium (NiTi) rotary files and the WaveOnefile. Eighty mandibular first molars were selected and divided into 4 groups. Hand file(HFs), WaveOne reciprocating file (WO), EndoSequence file (ES), ProTaper file(PT), were used to prepare the 2 mesial canals. Roots were then sectioned 3, 6, and 9mm from the apex, and the cut surface was observed under a microscope and checkedfor the presence of dentinal defects. HF group showed the lowest percentages ofdentinal defects (5%). In roots prepared with the WO, ES, and PT, dentinal defectswere observed in 25%, 10%, and 50% of teeth, respectively. There was a significantdifference between HFs group and both of WO group and PT group (P &lt;0.05).However, no significant difference was found between HFs group and ES group (P ≥0.05). Also a non significant difference was found between WO group and ES group(P ≥ 0.05). All rotary files created defects in the root dentin, whereas handinstrumentation presented with satisfactory results.

Impact of glide path preparation on the incidence of dentinal defects after preparation of severely curved root canals.

The purpose of this study was to evaluate the impact of glide path preparation on the incidence of dentinal defects after preparation of severely curved canals using ProTaper Next, F6 SkyTaper, and One Shape instruments. One hundred and forty human mandibular molars with mesiobuccal canals with angles of curvatures ranging between 25 and 35 degrees and radii ranging between 4 and 9 mm were assigned to seven homogenous groups (n = 20 teeth per group). In half of the teeth of each of the seven groups a manual glide path (size 15) was created prior to instrumentation. The root canals were instrumented using the three different types of instruments to an apical size 25. One group served as control as no canal preparation was performed. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a microscope using 25-fold magnification. The presence of dentinal defects (complete/incomplete cracks) was noted and analyzed using Fisher's exact test. No defects were observed in the controls. All canal preparations created dentinal defects. More incomplete and complete cracks were found in the apical (n = 4) and the middle (n = 3) canal third than in the coronal (n = 1), without any significant differences between the three instruments (P > .05). Prior glide path preparation had no significant impact on the incidence of dentinal defects (P > .05). A glide path preparation seems not to be mandatory to reduce the risk of dentinal defects formation when using the tested instruments in severely curved canals.

Incidence of Dentinal Defects on the External Apical Root Surface after Instrumentation with WaveOne Reciprocating Files at Different Working Lengths

IntroductionThe aim of this in vitro study was to identify the formation of dentinal defects on the external apical root surface of teeth instrumented at different working lengths by using WaveOne reciprocating files. MethodsSixty human single-rooted mandibular premolars were divided into 3 groups (n = 20) according to the file used for instrumentation: WaveOne Small (WOS), premolars presenting mechanical resistance to the penetration of #10 K-file 1 mm short of the apical foramen; WaveOne Primary (WOP), this limit easily reached with #10 K-file; and WaveOne Large (WOL), this limit easily reached with #20 K-file or higher. A closed system and a muffle were created to allow alternating sessions of root canal instrumentation and image acquisition. The teeth were further divided according to 3 different working lengths: 1 mm short of the apical foramen, flush with the apical foramen, and 1 mm beyond the apical foramen. Micrographs of the external apical root surface of each specimen at baseline and after instrumentation up to each working length were examined for the presence of dentinal defects. Inter-examiner agreement was evaluated by using Pearson correlation test, and the Kruskal-Wallis test was used to analyze intragroup and intergroup differences (P < .05). ResultsInter-examiner agreement was high in all experimental groups (r = 1.0000, r = 0.8885, and r = 0.7867 for WOS, WOP, and WOL, respectively). There was no significant difference in the number of teeth with dentinal defects in the intergroup (P = .8119) or intragroup analyses (P = .9309, .8648, and .4772 for WOS, WOP, and WOL, respectively). ConclusionsInstrumentation with different WaveOne files up to different working lengths was not associated with the formation of dentinal defects.

Farklı Nikel Titanyum Döner Eğe Sistemleri ile Şekillendirme Sonrası Görülen Dentin Defekti İnsidansı

Amaç: Revo-S, ProTaper Next ve Twisted File Adaptif NiTi eğelerinin mandibuler keser dişlerin kök kanallarının şekillendirilmesi sırasında dentin defekti oluşturma sıklıklarının karşılaştırılmasıdır. Gereç ve Yöntemler: Yüz yirmi adet kök ucu gelişimi tamamlanmış, düz köklü mandibuler keser diş çalışmaya dâhil edildi. Otuz diş herhangi bir işlem yapılmadan negatif kontrol grubu olarak ayrıldı. Doksan diş her bir grupta 30 adet olacak şekilde üç gruba ayrıldı; ProTaper Next (PTN), Revo-S ve TF Adaptif (TFA) kullanılarak kök kanalları prepare edildi. Örneklerden su soğutması altında, dişin uzun aksına dik olacak şekilde apeksten 3, 6 ve 9 mm uzaklıkta üç adet kesit elde edildi. Elde edilen kesitler stereomikroskop altında x25 büyütme ile dentin defekti varlığı yönünden incelendi. Elde edilen veriler ki-kare testi kullanılarak istatistiksel olarak analiz edildi (p<0,05). Bulgular: Test edilen bütün NiTi eğe sistemlerinin kontrol grubuna göre istatistiksel olarak daha fazla dentin defekti oluşturduğu saptanmıştır (p<0,05). TFA sisteminin PTN ve Revo-S grubuna göre istatistiksel olarak daha az dentin defekti oluşturduğu bulunmuştur (p<0,05). Farklı seviyelerden alınan kesitler ile dentin defekti miktarı arasında bir korelasyon saptanmamıştır (p>0,05). Sonuç: Çalışmamızda test edilen bütün NiTi eğelerin kök kanal dentininde defekte neden olduğu bulunmuştur. TFA sisteminin PTN ve Revo-S grubuna göre istatistiksel olarak daha az dentin defekti oluşturduğu bulunmuştur.

Comparative evaluation of dentinal defects induced by hand files, hyflex, protaper next and one shape during canal preparation: A stereomicroscopic study

Aim: This study aims to evaluate and compare the incidence of dentinal defects induced by Hand Files, HyFlex CM, ProTaper Next (PTN), and One Shape during canal preparation. Materials and Methods: One hundred and fifty extracted mandibular premolar teeth with single root canal were selected. Specimens were then divided into five groups with thirty specimens each. Group I: Specimens were prepared with hand instruments. Group II: Specimens were prepared with HyFlex CM rotary files (Coltene) using a crown-down technique according to the manufacturer's instructions. Group III: Specimens were prepared with PTN rotary files (Dentsply) using a crown-down technique according to the manufacturer's instructions. Group IV: Specimens were prepared with One Shape Single file rotary system (MicroMega) using a crown-down technique according to the manufacturer's instructions. Group V: Specimens were used as a control and left unprepared. All roots were cut horizontally at 3, 6, and 9 mm from the apex. Sections were then viewed under stereomicroscope and dentinal defects were registered as “no defect,” “fracture,” and “other defects.” Statistical Analysis: Results of the study were subjected to Chi-square test. Results: Results were expressed as the number and percentage of defected, partially defected and roots with no defects in each groups. Conclusion: Hand files and One Shape file system caused less root defects compared to PTN and HyFlex file systems.

Incidence of dentinal defects after preparation of severely curved root canals using the Reciproc single-file system with and without prior creation of a glide path.

To investigate the incidence of dentinal defects after preparation of severely curved root canals using the Reciproc single-file system with and without prior creation of a glide path. Mesial roots from extracted mandibular first molars were collected and scanned with CBCT to assess the morphology of the root canal systems. Three groups of 20 anatomically comparable specimens were generated. The control group was left unprepared, whilst the experimental groups were prepared with Reciproc R25 with and without a glide path (groups RG and R, respectively). Roots were then sectioned perpendicular to the long axis at 2, 4, 6, 8 and 10mm from the apex, and coloured photographs of the sections at 40× were obtained. Two blinded examiners registered the presence of dentinal defects twice at 2-week interval. Data were statistically analysed using the Fisher exact and Cochran's Q tests. No defects were observed in the control group. The overall incidence of dentinal defects was 26% in group R and 24% in group RG, with no significant differences between them (P>0.05). Dentinal defects occurred significantly more often in the middle and coronal thirds compared to the apical third of the canals (P<0.05). Prior preparation of a glide path had no impact on the incidence of dentinal defects when using Reciproc files.

The Effect of Using RC Prep during Root Canal Preparation on the Incidence of Dentinal Defects

IntroductionThe purpose of this in vitro study was to evaluate the effect of using RC Prep (Well-Prep, Vericom Co, Anyang, Korea) during root canal preparation on the incidence of defects in root canal walls. MethodsOne hundred extracted mandibular incisors with single canals were randomly divided into 1 control group and 4 experimental groups (n = 20). The teeth in group 1 (control) were coronally flared with Gates Glidden drills (Mani, Japan), but no further preparation was made. All teeth in the experimental groups were first coronally flared with Gates Glidden drills and then prepared similarly by means of ProTaper instruments (Dentsply Maillefer, Ballaigues, Switzerland). The difference between the experimental groups was the following: in group 2, saline was used as an irrigation solution without the application of RC Prep; in group 3, teeth were irrigated with saline, and RC Prep was also applied to canals before the insertion of each file; in group 4, sodium hypochlorite (NaOCl) was used for irrigation without the application of RC Prep; and in group 5, both NaOCl and RC Prep were used. The apical root surface and horizontal sections 3, 6, and 9 mm from the apex were observed under a microscope. The presence of cracks was noted. The chi-square test and Fisher exact test were used for statistical analysis of differences between and among the groups. ResultsA significant difference was found between and among the 5 groups (P < .05). Group 4 (NaOCl), which had the highest number of cracked teeth, was significantly different from group 1 (control) (P < .05). RC Prep, with both saline and NaOCl, had no significant effect on the incidence of microcrack formation (P > .05). When data were pooled, regardless of whether RC Prep was used, there was a significant difference between saline (groups 2 + 3) and NaOCl (groups 4 + 5) (P < .05). ConclusionsRC Prep was unable to reduce the risk of dentinal defects. NaOCl caused more defects compared with saline.

Radicular dentinal defects incidence after using EDTA gel with different root canal instrumentation techniques

Objectives: The purpose of this study was to compare the incidence of dentinal defect formation after using EDTA gel during root canal preparations by three different instrumentation techniques. Materials and Methods: One hundred and forty maxillary central incisors were decoronated and roots were embedded in resin blocks. Twenty samples were left unprepared (Control group), and the remaining 120 samples were divided into three groups. Each group was divided equally into two subgroups according to the use of EDTA gel during root canal instrumentation. Roots were prepared with hand file (Group 1), ProTaper Universal (Group 2) and WaveOne (Group 3). Roots were sectioned 3, 6, and 9 mm from the apex, and the cut surface was observed microscopically and the presence of dentinal defects was checked. The differences between groups were analyzed using Fisher's exact test. Results: Unprepared roots did not show any dentinal defects. Dentinal defects were observed in all prepared roots. The difference between experimental groups and subgroups regarding the incidence of dentinal defects was not statistically significant. Conclusion: Canal preparation using hand or rotary files created radicular dentinal defects. The use of EDTA gel during root canal preparation did not reduce the incidence of dentinal defects.

Mechanical or cold lateral compaction: The incidence of dentinal defects

The incidence of dentinal defects may influence the outcome of root canal treatment. The aims of this study were to evaluate and compare the incidence of dentinal defects following root canal obturation with two different techniques. A total of 110 mesial roots of human mandibular first molars were selected. Twenty-seven roots were left unprepared as negative controls (NCs). The mesiobuccal canals of 83 roots were prepared using rotary instruments. Twenty-seven roots were left unobturated as positive controls (PCs). Twenty-eight roots were obturated with cold lateral compaction (CLC) technique and the others were obturated with mechanical lateral compaction (MLC) technique. In the CLC and MLC groups, spreader penetration depth was measured by an electromechanical testing machine in canals containing master Gutta-percha cones. After root canal obturation, all the roots were sectioned horizontally at four levels from the apex and evaluated under a stereomicroscope at a magnification of ×40. The presence of dentinal defects was noted. Data were analyzed using the Chi-square and t-tests. The number of defects was not significantly different between the CLC, MLC, and PC groups. The CLC, MLC, and PC groups had significantly more defects compared to the NC group. According to the results of this study, the MLC and CLC techniques were the same in producing dentinal defects.

Dentin-Hartsubstanzdefekte als Folge maschineller Wurzelkanaltherapie

S. Bürklein, P. Tsotsis, E. Schäfer. Incidence of Dentinal Defects after Root Canal Preparation: Reciprocating versus Rotary Instrumentation. J Endodontics 2013; 39: 501–504

The effects of canal preparation and filling on the incidence of dentinal defects

To evaluate ex vivo the incidence of defects in root dentine before and after root canal preparation and filling. Eighty extracted mandibular premolars were divided equally in four groups. Group 1 was left unprepared. All other root canals were prepared using Gates Glidden drills and System GT files up to size-40, 0.06 taper at the working length. Group 2 was not filled while the canals of the other groups were filled with gutta-percha and AH26, either with a master cone and passive insertion of secondary gutta percha points (group 3) or lateral compaction (group 4). Roots were then sectioned horizontally 3, 6, and 9 mm from the apex and observed under a microscope. The presence of dentinal defects (fractures, craze lines or incomplete cracks) was noted and the differences between the groups were analysed with the Fisher's exact test. No defects were observed in the roots with unprepared canals. The overall difference between the groups was significant (P < 0.05). Canal preparation alone created significantly more defects than unprepared canals (P < 0.05). The total number of defects after lateral compaction was significantly larger than after noncompaction canal filling. Root canal preparation and filling of extracted teeth created dentine defects such as fractures, craze lines and incomplete cracks.