Hesna Sazak Öveçoğlu

Comparison of ProTaper and Mtwo retreatment systems in the removal of resin‐based root canal obturation materials during retreatment

To evaluate the effectiveness of the ProTaper and Mtwo retreatment systems for removal of resin-based obturation techniques during retreatment. A total of 160 maxillary anterior teeth were enlarged to size 30 using ProTaper and Mtwo rotary instruments. Teeth were randomly divided into eight groups. Resilon + Epiphany, gutta-percha + Epiphany, gutta-percha + AH Plus and gutta-percha + Kerr Pulp Canal Sealer (PCS) combinations were used for obturation. ProTaper and Mtwo retreatment files were used for removal of root canal treatments. After clearing the roots, the teeth were split vertically into halves, and the cleanliness of the canal walls was determined by scanning electron microscopy. Specimens obturated with gutta-percha and Kerr PCS displayed significantly more remnant obturation material than did specimens filled with resin-based obturation materials. Teeth prepared with Mtwo instruments contained significantly more remnant filling material than did teeth prepared with ProTaper. ProTaper files were significantly faster than Mtwo instruments in terms of the mean time of retreatment and time required to reach working length. The Resilon + Epiphany and AH Plus + gutta-percha obturation materials were removed more easily than were the Epiphany + gutta-percha and Kerr PCS + gutta-percha obturation materials. Although ProTaper retreatment files worked faster than did Mtwo retreatment files in terms of removing root canal obturation materials, both retreatment systems are effective, reliable and fast.

Radiologic Assessment of Periapical Health: Comparison of 3 Different Index Systems

INTRODUCTION The aim of this study was to evaluate observer variations and observer reproducibility in the interpretation of periapical health using the Strindberg system, the periapical index (PAI), and the probability index for radiologic assessment of periapical health. METHODS Four observers read digital periapical images to evaluate the periapical health of 200 root-filled teeth. Each observer evaluated a tooth twice by using the Strindberg system, twice by using the PAI, and twice by using the probability index. Each observation session was held at 1-month intervals. Three scores were used for the evaluations conducted by using the Strindberg system. Both the PAI and the probability index were considered on 5-point scales and were also dichotomized. SPSS for Windows 15.0 software (SPSS Inc, Chicago, IL) was used for data analysis, and intra- and interobserver agreements were described by using kappa statistics. RESULTS The average kappa values of intra- and interobserver agreement calculated for the Strindberg system were 0.53 and 0.36, respectively. The corresponding average kappa values were calculated as 0.48 and 0.39 for the PAI and 0.45 and 0.30 for the probability index. The highest mean proportion values of intra- and interobserver agreement were observed for the dichotomization of the PAI (88.9% and 87.0%, respectively) followed by the dichotomization of the probability index (86.8% and 82.9%, respectively). CONCLUSIONS The Strindberg system has lower intraobserver variation compared with the PAI and the probability index, whereas PAI has lower interobserver variation compared with the Strindberg system and the probability index. The dichotomization of the PAI and the probability index provided higher intra- and interobserver agreement values in the radiologic assessment of periapical health.

Efficacy of XP-Endo Finisher in the Removal of Triple Antibiotic Paste from Immature Root Canals.

Introduction The aim of this study was to evaluate and compare the effectiveness of the XP‐Endo Finisher (FKG Dentaire, La Chaux‐de‐Fonds, Switzerland) with passive ultrasonic irrigation (PUI) and needle irrigation in the removal of triple antibiotic paste (TAP) from the straight immature root canals of extracted teeth. Methods Thirty‐four freshly extracted single‐rooted teeth were used. All canals were prepared up to the ProTaper F5 file (Dentsply Maillefer, Ballaigues, Switzerland). Apices were drilled to simulate teeth with immature apices. The canals were filled with TAP, sealed, and incubated at 37°C and 100% humidity for 1 month. Samples were randomly assigned to 3 experimental groups according to the method used for TAP removal: XP‐Endo Finisher, PUI, and needle irrigation (n = 10). Then, the roots were split into 2 halves. The amount of TAP residue in the apical portion of each segment was evaluated using a scanning electron microscopy and scored. Results The amount of remaining TAP was significantly lower in the XP‐Endo Finisher group compared with the needle irrigation and PUI groups (P < .05). Between the needle irrigation and PUI groups, there were no statistically significant differences (P > .05). Conclusions Within the limitations of this study, the XP‐Endo Finisher removed significantly more TAP than needle irrigation and PUI.

Assessment of the periapical health of abutment teeth: A retrospective radiological study.

AIM The aim was to examine the technical quality of root fillings and periapical status of root-filled and nonroot-filled teeth restored with crowns and bridge retainers through a retrospective analysis of orthopantomographs (OPTGs) in an adult Turkish subpopulation. MATERIALS AND METHODS In this study, the digital OPTGs of adult patients between the ages of 20 and 70 who appealed to the Endodontics Endodontics Department of the Dentistry Faculty at Marmara University (Istanbul, Turkey) for the first time to have their endodontic treatment needs met were used. The periapical health of all teeth restored with crowns and bridge retainers, and the technical quality of the root fillings on abutment teeth were evaluated by radiographic criteria. RESULTS The survey was carried out using the OPTGs of 1000 adult patients composed of 590 (59.0%) women and 410 (41.0%) men. 4656 (20.9%) of the totally examined 22280 teeth were with crowns and bridge retainers. 986 of the total abutment teeth were root-filled and 458 (46.5%) of them had apical periodontitis (AP) while 3670 of the total abutment teeth were nonroot-filled and 930 (25.3%) of them were with AP. The most commonly treated teeth were premolars (33.8%), followed by molars (26.2%), incisors (23.3%) and canines (16.7%). Technical quality was proved to be adequate in 27.5% of the root fillings. A higher frequency of AP was related to inadequate root fillings (P<0.01). CONCLUSION The frequency of root-filled abutment teeth with AP, nonroot-filled abutment teeth with AP, and technically inadequate root-fillings among teeth with crowns and bridge retainers was high in the selected adult population.

Comparison of intracoronal bleaching methods on teeth discolored by different antibiotic pastes

Aim: To compare the bleaching efficacy of sodium perborate with different activation methods on crowns discolored by two different antibiotic pastes. Materials and Methods: Eighty-five extracted human incisors were prepared to size #30 using ProTaper rotary instruments. After chemomechanical preparation and irrigation procedures, the specimens received triple antibiotic paste (TAP, n = 40), minocycline paste (MP, n = 40), or calcium hydroxide (n = 5, control group) and coronally sealed with temporary filling material. Spectrophotometric readings were obtained on day 0–week 4. Data were analyzed with the Mann–Whitney U-test and Wilcoxon sign test (P < 0.05). Sodium perborate was then inserted into the pulp chambers of discolored teeth (four subgroups, n = 10) and activated by heat or ultrasonically using two different frequencies and times. Spectrophotometric readings were obtained on days 3–7. Data were analyzed by the Mann–Whitney U-test and Kruskal–Wallis test (P > 0.05). Results: Both groups showed statistically significant coronal discoloration at each time interval (P < 0.01), but their final shades did not significantly differ between the groups (P > 0.05). Although the MP subgroups exhibited more bleaching than the TAP subgroups on days 3 and 7, the difference was not significant (P > 0.05). The bleaching results for the sodium perborate activation techniques did not significantly differ among groups (P > 0.05). Conclusions: Both antibiotic pastes induced crown discoloration that was reversible using all sodium perborate bleaching techniques.

Fractographic analysis of ProTaper and Mtwo systems: Breakage and distortion in severely curved roots of molars

Aim: This study evaluated the distortion and fracture mode of ProTaper and Mtwo rotary instruments following their use in severely curved root canals in extracted human teeth. Materials and Methods: A total of 30 mesial canals of mandibular molars were allocated into two groups that were balanced in terms of angle and radius of curvature. Canals were prepared by either ProTaper or Mtwo systems. Each set of instruments was changed after the third canal. Longitudinal and fractographic examinations of the instruments were carried out by scanning electron microscopy. Images were evaluated according to distortion and mode of fracture. Chi-square analysis and Fisher′s exact test were carried out at a significance level of P < 0.05. Results: No significant difference was found between fracture and distortion percentage of ProTaper and Mtwo rotary instruments (P > 0.05). Fractographic analysis revealed that all of the Mtwo instruments demonstrated torsional failure and all but one of the ProTaper instruments (S1) showed torsional failure. Conclusion: Fractographic examination of the fractured surface revealed shear fracture was the predominant mode of failure. Root canal curvature was an essential parameter influencing the susceptibility of instruments to fracture.

Evaluation of the Efficacy of Self-Adjusting File Instrumenton Oval-shaped Root Canals

Purpose;Oval-shaped canals are a challenge when using rotary files because buccal and/or lingual recesses are commonly left uninstrumented. The aim of this study was to evaluate root canal preparation in flat- oval canals treated with ProTaper, Reciproc or self-adjusting file (SAF) instruments. Methodology; 60 mandibular premolars were divided into three groups. After biomechanical preparation, teeth were embedded in acrylic blocks. Roots were then sectioned 4, 8, and 12 mm from the apex using a precise saw, and the cut surfaces in the apical, middle, and coronal thirds were observed under a stereomicroscope at ×40 magnification. Results;The areas of prepared canal walls were significantly higher with the SAF than the ProTaper or Reciproc instruments (p<0.05). The SAF removed the dentin layer from all around the canal, whereas the others left substantial untouched areas. The area in the apical third of the teeth prepared with the Reciproc was significantly higher than with the other techniques, likely due to the high taper of the Reciproc file (p<0.01).Conclusions;In the coronal third, mean increases in the area of the canal were significantly higher with the SAF than with ProTaper or Reciproc. Using the SAF instrument, flat-oval canals were prepared homogenously and circumferentially.

Canal Centring Ability of ProTaper and Mtwo Rotary Systems in Curved Canals

SUMMARY The purpose of this investigation was to compare centring ratio of ProTaper and Mtwo rotary systems. 60 mandibular molar teeth which had 25, 30 and 35 degree curvature in mesio-buccal root canal were used. Group 1 had 25°, Group 2 had 30°, and Group 3 had 35° curvatures. The roots were sectioned horizontally at 2 mm away from the apex. The apical region was then observed under a stereo-microscope. In each group, teeth were instrumented using ProTaper and Mtwo systems. After canal preparation, digital images of apical part of canals were taken. These images were then superimposed by using Adobe Photoshop CS2 programme. The data were analyzed using ANOVA and Student’s t-test. No significant differences were found between each curvature degrees and rotary systems at the apical part of curved root canals (p<0.05).

Comparison of protaper and mtwo retreatment systems for working time in the removal of resin-based root canal obturation materials during retreatment

Amaç: Bu çalışmada retreatment amacıyla kullanılan Ni-Ti esaslı döner sistemlerin (ProTaper Retreatment, Mtwo R) kök kanallarından rezin esaslı kanal dolgu materyallerinin sökülme sürelerinde bir etkisinin olup olmayacağının incelenmesi amaçlanmıştır. Yöntem: Çalışmamızda 160 adet çekilmiş maksiller anterior diş kullanılmıştır. Bu dişler ProTaper ve Mtwo döner sistemleri ile genişletilmiştir. Daha sonra dişler rastgele sekiz gruba ayrılmıştır (n=20). Grup 1 ve 5 Resilon-Epiphany kök kanal dolum sistemi, Grup 2 ve 6 güta-perka ve Epiphany, Grup 3 ve 7 güta-perka ve AH Plus, Grup 4 ve 8 ise, kontrol grubu olarak, güta-perka ve öjenol esaslı kanal dolgu patı Pulp Canal Sealer ile dolduruldu. ProTaper ile genişletilen dişlerin kök kanal sökümleri ProTaper Retreatment eğeleri, Mtwo ile genişletilen dişlerin sökümleri ise Mtwo Retreatment eğeleri ile yapıldı. Çalışma boyuna ulaşmak için geçen süre (T1), tekrar şekillendirme için geçen süre (T2) ve retreatment için geçen toplam süre (Tt) kronometre ile ölçüldü. Bulgular: Retreatment çalışma süreleri, kök kanallarının başlangıç şekillendirmesinde kullanılan iki döner sisteme göre değerlendirildi. T1 süreleri arasında istatistiksel olarak anlamlı farklılık bulunmaktadır. Mtwo kullanılan dişlerde T1, T2 ve Tt süreleri, ProTaper kullanılan dişlerden anlamlı şekilde uzundur. Dolum şekline göre T1, T2 ve Tt süreleri arasında istatistiksel olarak anlamlı farklılık bulunmaktadır. Dolum şekli Gütaperka+AH Plus olan dişlerin çalışma süreleri, diğer tekniklerle doldurulan dişlerden anlamlı düzeyde kısadır. Mtwo ile şekillendirilen dişlerin T1, T2 ve Tt süreleri, dolum ve retreatment tekniklerinden bağımsız olarak, ProTaper ile şekillendirilen dişlerden uzun bulundu. Sonuç: Araştırmamızın sonuçlarına göre, ProTaper Retreatment eğelerinin Mtwo Retreatment eğelerine kıyasla, kanal dolum materyallerini kök kanallarından daha çabuk uzaklaştırdıkları sonucuna varılmıştır. Anahtar sözcükler: ProTaper, Mtwo, rezin, epiphany, retreatment zamanı ABS TRACT Comparison of protaper and mtwo retreatment systems for working time in the removal of resinbased root canal obturation materials during retreatment

Clinical Success of IPS Empress II Inlays/Onlays

For the dental restorations, ceramic materials have increasing popularities because of their biocompatibility and superior esthetics. IPS Empress which is leucite-reinforced glass ceramic is one of the most popular ceramics. IPS Empress II was developed in following years which is stronger than IPS Empress. In the dental applications some problems occur about ceramic restorations. Hence,this study was performed to examine the six-year clinical performance of IPS Empress II ceramic onlay and inlay restorations.