Pulpectomies with Iodoform Versus Calcium Hydroxide-Based Paste: A Preliminary Randomised Controlled Clinical Trial

ABSTRACT Objective: To compare clinical and radiographical pulpectomy outcomes in primary teeth filled with different pastes. Material and Methods: The sample included thirty-eight teeth indicated for pulpectomy due to irreversible pulp inflammation or necrosis from thirty patients (2 to 9 years old). The first appointment comprised chemomechanical preparation (2.5% sodium hypochlorite), smear layer removal (6% citric acid), intracanal dressing and temporary restoration. Seven days later, teeth were randomly assigned to filling with iodoform (IP) or calcium hydroxide with zinc oxide (CHZO) based pastes and temporarily restored. Final restoration (composite resin) occurred at the 3rd appointment. Data from baseline, 6 and 12 months were analysed using descriptive and inferential statistics (p≤0.05). Results: The overall frequency of success was 63.6% (n=21), with no significant difference between groups (IP=62.5% n=10; CHZO=64.7% n=11, p=0.59). Multiradicular teeth, overfilled canals and teeth whose coronal restoration have been lost were significantly associated with failure (p=0.01, p=0.04 and p<0.001, respectively). Conclusion: After 12 months, both pastes showed similar outcomes and can be used as good options for pulpectomies in primary teeth. Moreover, tooth location, extent of the root canal filling, and integrity of final restoration during the follow-up influenced the outcome of pulpectomies.

Do Different Proportions of Antibiotics in the CTZ Paste Interfere with the Antimicrobial Action? In Vitro Study

Abstract Objective: To evaluate the antimicrobial action of the CTZ paste in three different proportions by diffusion in agar with the microorganisms: Enterococcus faecalis,Escherichia coli, and Candida albicans. Material and Methods: Three different proportions of antibiotics were tested: GROUP A - CTZ paste in the ratio of 33.33% chloramphenicol + 33.33% tetracycline + 33.33% zinc oxide, mixed with 2 drops of eugenol (1:1:1 ratio); GROUP B - CTZ paste in the proportion of 25% chloramphenicol + 25% tetracycline + 50% zinc oxide, mixed with 2 drops of eugenol (1: 1: 2 ratio); GROUP C - CTZ paste with 13% chloramphenicol + 13% tetracycline + 74% Zinc Oxide, mixed with 2 drops of eugenol (1:1:6 ratio); PC GROUP - Positive Control (0.12% Chlorhexidine); and NC GROUP - Negative Control (0.9% Saline solution). Data were analyzed through descriptive statistics (means and standard deviation). The one-way ANOVA and Tukey's test were used, with a significance level of 5% Results: No statistical differences for Enterococcus faecalis between groups A, B, and C (p = 0.1986) were found. There were statistical differences for Escherichia coli between groups B and C (p = 0.029), and for Candida albicans between groups A and C (p = 0.006). Groups A, B, and C had significant differences with both Positive and Negative Controls for all the microorganisms Conclusion: The three different ratios of CTZ paste showed antimicrobial efficacy against Enterococcus faecalis,Escherichia coli, and Candida albicans microorganisms.

Endodontic Treatment of Primary Molars with Antibiotic Paste: A Report of 38 Cases.

OBJECTIVE: This study presents 38 cases of primary molars with necrotic pulps treated with antibiotics-based paste. CASE REPORT: The technique consisted of necrotic tissue removal of the pulp chamber, using spoons excavators and low speed drills. Pulp cavity was washed with saline solution and dried with sterile cotton balls. Then an antibiotic paste composed of chloramphenicol, tetracycline, zinc oxide and eugenol - CTZ paste - was inserted at the entrance of root canals. Patients were evaluated clinically and radiographically at different times. The criteria that defined clinical success were the lack of periapical abscess and mobility compatible with chronological age. Radiographic assessments consisted in absence of radiolucency in the region of root bifurcation and pathological bone resorption. CONCLUSION: There were 100% and 93% of clinical and radiographic success, respectively. The results suggest that the CTZ paste is an optional therapy for pulp of primary molars.

Comparison of pulp stump wounds created by profile rotary root canal instruments and small-diameter fine diamond burs.

INTRODUCTION: The aim of this investigation was to evaluate and compare the pulp stump wounds created by the following root canal instruments: ProFile rotary files and small-diameter fine diamond burs. METHODS: Extracted mandibular premolars from adult patients with vital pulps and fully formed root canals were collected and stored in formalin. Within 48 hours of extraction, the periapical tissue was fixated to the root with a double coating of ethyl cyanoacrylate, and the pulp chambers were accessed with a #4 round carbide bur and high-speed handpiece in a traditional fashion. The pulp tissue of 10 specimens per group was extirpated at a level approximately 5 mm from the apex by using standard endodontic techniques. The specimens were then examined at ×100 magnification under a digital microscope. Grading criteria were developed, and the wounds were scored. RESULTS: Wounds created by diamond burs were significantly smoother that those created by ProFile rotary files; the mean wound score for diamond burs was 1.4 versus a mean wound score of 3 for ProFiles. After the author's scoring of the wounds, 2 endodontist graders were shown photos of each specimen in a double-blind fashion and instructed to score each specimen as being smooth or rough. To validate the developed scoring system and remove potential observer bias of the author, the data from the double-blind observations were used to complete a cross-tabulation for a Cohen kappa test. CONCLUSIONS: Kappa values demonstrated substantial inter-rater agreement for both groups.

Effect of working length measurement by electronic apex locator or digital radiography on postoperative pain: a randomized clinical trial.

INTRODUCTION: The aim of this study was to evaluate the effect of working length determination methods, electronic apex locator and digital radiography, on postoperative pain. METHODS: Two hundred twenty patients with asymptomatic single-rooted vital teeth were randomly assigned to 2 groups according to the method used for working length determination, the radiographic group and the electronic apex locator group. After working length determination, chemomechanical preparation was performed in a crown-down technique with ProTaper instruments. A master cone radiograph was taken. Canals were obturated with gutta-percha and sealer by using a lateral compaction technique. Postoperative pain was assessed after 4, 6, 12, 24, and 48 hours by using a 4-point pain intensity scale. In addition, patients were asked to record the number of days necessary to achieve complete pain resolution. RESULTS: Postoperative pain during the 4-hour to 48-hour interval studied was not significantly different (P > .05) between groups. The mean times for pain dissipation in the radiographic and electronic apex locator groups were 3.37 ± 2.79 and 3.88 ± 3.34 days, respectively. The difference between groups was not statistically significant (P > .05). CONCLUSIONS: There is no difference in postoperative pain between working length measurement methods by using an electronic apex locator or digital radiography. The reduced exposure to radiation by using apex locator may be a factor that influences a dentist's decision to choose the electronic apex locator over radiography.

Effectiveness of three instrumentation systems to remove Enterococcus faecalis from root canals.

AIM: To assess the effectiveness of three systems of mechanical preparation to reduce Enterococcus faecalis within root canals. METHODOLOGY: Twenty-four human single-rooted canine teeth were standardized to a length of 17 mm and the canal contents removed using a size 20 K-file, as the last apical file. After irrigation and sterilization, the canals were contaminated with E. faecalis and incubated for 21 days at 37 °C with 5% CO(2). Then, the teeth were divided into three groups for mechanical preparation with: ProTaper rotary system, ProTaper manual system and manual K-files. Samples of the root canal contents, before and after the debridement, were collected with sterile paper points for 1 min. Then, the samples were diluted and plated in Brain Heart Infusion (BHI) agar. The colony-forming units were counted and the percentage reduction calculated. The reduction and log CFU mL(-1) were compared between groups using Wilcoxon nonparametric test and two-way analysis of variance, respectively. RESULTS: There was a significant reduction in the number of CFU/mL (P = 0.000) before and after debridement for all the systems used. However, there was no significant difference between the systems. CONCLUSION: All the three instrumentation systems reduced E. faecalis counts to a similar degree.

Anesthetic efficacy of four percent articaine for pulpal anesthesia by using inferior alveolar nerve block and buccal infiltration techniques in patients with irreversible pulpitis: a prospective randomized double-blind clinical trial.

INTRODUCTION: The study was designed as a randomized double-blind trial to evaluate the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine in inferior alveolar nerve block (IANB) and infiltration anesthetic techniques to anesthetize mandibular molars with irreversible pulpitis. METHODS: The study was composed of 2 test arms and 1 control arm. Subjects in the test arms received either a standard IANB or a buccal infiltration (B Infil) of 4% articaine with 1:100,000 epinephrine, whereas the subjects in the control arm received a standard IANB of 2% lidocaine with 1:100,000 epinephrine. Subject's self-reported pain response was recorded on Heft Parker Visual Analogue Scale after local anesthetic administration during access preparation and pulp extirpation. RESULTS: For statistical analysis Pearson χ(2), Student's paired t test, 1-way analysis of variance, and Friedman tests showed no significant difference in success rates among the 3 arms of the trial. CONCLUSIONS: Although B Infil and IANB of 4% articaine were equally effective, B Infil can be considered a viable alterative in IANB for pulpal anesthesia in mandibular molars with irreversible pulpitis.

Comparison between rotary and manual techniques on duration of instrumentation and obturation times in primary teeth.

OBJECTIVE: The aim of this study was to compare the duration of instrumentation and obturation times and quality of root canal filling between rotary and manual instrumentation techniques in primary teeth. STUDY DESIGN: A randomized, controlled clinical trial was performed that included deciduous teeth with pulp necrotic. Forty necrotic teeth were included; 20 were instrumented with a rotary technique (experimental group) and 20 with a manual technique (control group). The time taken for instrumentation and for obturation were recorded in minutes, and the quality of the root canal filling was recorded as optimal, under-filled, or overfilled. RESULTS: The use of the rotary technique diminished the time of instrumentation to 63% and time of obturation to 68%, and it improved the quality of the root canalfilling. CONCLUSION: The use of rotary instruments in the pulpectomy of primary molars represents a promising technique; the time is significantly reduced.

Influence of cervical preflaring on determination of apical file size in mandibular molars: SEM analysis.

This study investigated the influence of cervical preflaring with different rotary instruments on determination of the initial apical file (IAF) in mesiobuccal roots of mandibular molars. Fifty human mandibular molars whose mesial roots presented two clearly separated apical foramens (mesiobuccal and mesiolingual) were used. After standard access opening and removal of pulp tissue, the working length (WL) was determined at 1 mm short of the root apex. Five groups (n=10) were formed at random, according to the type of instrument used for cervical preflaring. In group 1, the size of the IAF was determined without preflaring of the cervical and middle root canal thirds. In groups 2 to 5, preflaring was performed with Gates-Glidden drills, ProTaper instruments, EndoFlare instruments and LA Axxes burs, respectively. Canals were sized manually with K-files, starting with size 08 K-files, inserted passively up to the WL. File sizes were increased until a binding sensation was felt at the WL and the size of the file was recorded. The instrument corresponding to the IAF was fixed into the canal at the WL with methylcyanoacrylate. The teeth were then sectioned transversally 1 mm short of the apex, with the IAF in position. Cross-sections of the WL region were examined under scanning electron microscopy and the discrepancies between canal diameter and the diameter of IAF were calculated using the tool "rule" (FEG) of the microscope's proprietary software. The measurements (microm) were analyzed statistically by Kruskal-Wallis and Dunn's tests at 5% significance level. There were statistically significant differences among the groups (p<0.05). The non-flared group had the greatest discrepancy (125.30 +/- 51.54) and differed significantly from all flared groups (p<0.05). Cervical preflaring with LA Axxess burs produced the least discrepancies (55.10 +/- 48.31), followed by EndoFlare instruments (68.20 +/- 42.44), Gattes Glidden drills (68.90 +/- 42.46) and ProTaper files (77.40 +/- 73.19). However, no significant differences (p>0.05) were found among the rotary instruments. In conclusion, cervical preflaring improved IAF fitting to the canals at the WL in mesiobuccal roots of maxillary first molars. The rotary instruments evaluated in this study did not differ from each other regarding the discrepancies produced between the IAF size and canal diameter at the WL.

Endodontics in primary molars using ultrasonic instrumentation.

PURPOSE: The purpose of this study, which is a series of consecutive case reports, was to describe and evaluate the protocol used in the treatment of pulpal necrosed of primary molars, used by the dental service of Social Support Foundation of the Moinhos de Vento Hospital, Porto Alegre, RS, Brazil. METHODS: Eighteen primary molars in 15 children, ranging from 4 to 10 years of age, were endodontically treated using ultrasonic instrumentation. RESULTS: Clinical and radiographic controls showed a success rate of 94%, considering an evaluation time of 14.1+/-6.3 months. CONCLUSIONS: The use of ultrasonic instrumentation in primary molars with pulpal necrosis succeeded in reducing appointment time and showed a high success rate.

Study of root canal accessibility in human primary molars.

The aim of the present study was to provide a general scheme for pulpectomy of primary molars that may be useful for decision-making about negotiation of root canals and selection of appropriate instruments. A total of 160 vital primary molars in 85 patients (40 males, 45 females) aged 4-6 years were selected. After taking primary radiographs, local anesthesia was induced, and the teeth were isolated using a rubber dam. Canal accessibility index (CAI) and tooth accessibility index (TAI) were calculated according to initial file size. Mandibular first molars had either three canals (79.2%) or four canals (20.8%), and all second molars had four canals. Maxillary first molars had three canals and second molars had either three canals (70.9%) or four canals (29.1%). Lower accessibility of the mandibular first molar distobuccal root accounted for the lower accessibility of these teeth in comparison with mandibular second molars. While three-canal maxillary second molars were more accessible due to the lower accessibility of the distobuccal canal of the maxillary first molar, poor accessibility of the distal canal in four-canal second molars was responsible for the difficult accessibility of these teeth. In conclusion, it seems that the accessibility of a single canal in each tooth determines the difficulty of accessibility for any given tooth. Moreover, while primary second molars are more accessible than first molars, all of them are negotiable.

Influence of cervical preflaring on determinationof apical file size in mandibular molars: SEM analysis

This study investigated the influence of cervical preflaring with different rotary instruments on determination of the initial apical file (IAF) in mesiobuccal roots of mandibular molars. Fifty human mandibular molars whose mesial roots presented two clearly separated apical foramens (mesiobuccal and mesiolingual) were used. After standard access opening and removal of pulp tissue, the working length (WL) was determined at 1 mm short of the root apex. Five groups (n=10) were formed at random, according to the type of instrument used for cervical preflaring. In group 1, the size of the IAF was determined without preflaring of the cervical and middle root canal thirds. In groups 2 to 5, preflaring was performed with Gates-Glidden drills, ProTaper instruments, EndoFlare instruments and LA Axxes burs, respectively. Canals were sized manually with K-files, starting with size 08 K-files, inserted passively up to the WL. File sizes were increased until a binding sensation was felt at the WL and the size of the file was recorded. The instrument corresponding to the IAF was fixed into the canal at the WL with methylcyanoacrylate. The teeth were then sectioned transversally 1 mm short of the apex, with the IAF in position. Cross-sections of the WL region were examined under scanning electron microscopy and the discrepancies between canal diameter and the diameter of IAF were calculated using the tool "rule" (FEG) of the microscope's proprietary software. The measurements (µm) were analyzed statistically by Kruskal-Wallis and Dunn's tests at 5 percent significance level. There were statistically significant differences among the groups (p<0.05). The non-flared group had the greatest discrepancy (125.30 ± 51.54) and differed significantly from all flared groups (p<0.05). Cervical preflaring with LA Axxess burs produced the least discrepancies (55.10 ± 48.31), followed by EndoFlare instruments (68.20 ± 42.44), Gattes Glidden drills (68.90 ± 42.46)...

Este estudo investigou a influência do alargamento cervical feito com diferentes instrumentos rotatórios na determinação do instrumento apical inicial (IAI) das raizes mésio-vestibulares de molares inferiores. Foram utilizados 50 molares inferiores cujas raízes mesiais apresentavam dois forames apicais nitidamente separados (mésio-vestibular e mésio-lingual). Após o acesso à câmara pulpar de forma convencional e remoção do tecido pulpar, o comprimento de trabalho foi definido a 1 mm do ápice radicular. Os dentes foram divididos aleatoriamente em cinco grupos (n= 10) de acordo com o tipo de instrumento utilizado no alargamento cervical. No grupo 1, o IAI foi definido sem o prévio alargamento dos terços médio e cervical das raízes. Nos grupos 2 a 5, o terço cervical e médio do canal radicular foi alargado com as brocas de Gates-Glidden, instrumentos Pro Taper, Endo Flare e brocas LA Axxes, respectivamente. A determinação do IAI foi realizada manualmente com limas tipo K em ordem crescente de diâmetro a partir da lima 08 até se chegar ao instrumento que permitisse ao operador ter a sensação tátil do mesmo estar firmemente ajustado ao CRT. O instrumento que correspondeu ao IAI foi fixado no interior do canal radicular com cianocrilato de metila. Com o IAI posicionado, os dentes foram seccionados transversalmente até 1 mm do ápice. As seções transversais do CRT foram observadas através da microscopia eletrônica de varredura e os desajustes entre o diâmetro do canal e o diâmetro do IAI foram calculados com a função "régua" (FEG) do software do próprio microscópio. Os resultados foram avaliados estatisticamente pelo testes de Kruskal-Wallis e Dunn ao nível de significância de 5 por cento. Houve diferenças estatisticamente significantes entre os grupos (p<0,05). O grupo sem alargamento apresentou o maior desajuste (125,30 ±51,54) e diferiu significativamente dos demais grupos (p<0,05). O alargamento cervical com as brocas LA Axxess apresentou...

Effect of Waterlase laser retrograde root-end cavity preparation on the integrity of root apices of extracted teeth as demonstrated by light microscopy.

Most endodontists use ultrasonic instruments for retrograde root-end cavity preparations even though they have been found to produce cracks. In this laboratory study, thirty-six randomly chosen roots had root-end cavity preparations made with the Waterlase laser and only one questionable intra-canal crack was found. It was concluded that the Waterlase laser when used to make endodontic root-end cavity preparations produces either no cracks, or a very low percentage (2.8%) of cracks.

Impact of a biological barrier in pulpectomies of primary molars.

PURPOSE: The purpose of this in vitro study was to determine whether placement of a resorbable collagen barrier at the apical one third of the root canal could prevent extrusion of pulpectomy filling material. METHODS: Twenty-five extracted primary mandibular second molars, with at least two thirds of root length remaining, were used. The apical third of each root was covered with utility wax, and teeth were embedded in acrylic. Carious tooth structure was removed, crowns were reduced to a flat surface, and canals were accessed and preflared. Working lengths were established by reducing file lengths 2 mm short of the anatomic apex. Cleaning and shaping was performed using hand and rotary files, and canals were irrigated with sodium hypochlorite and dried with paper points. CollaCote was randomly packed into 1 of 2 prepared canals, and obturation was performed with Vitapex. Postoperative radiographs were independently evaluated for the presence of overfilling, and data were statistically analyzed using chi-square analysis. RESULTS: Overfilling was observed in 16% (4/25) of the CollaCote treated canals and in 42% (10/24) of canals when no barriers were used (P = .047). CONCLUSION: The application of CollaCote at the apical one third of the canals did not completely prevent, but did significantly decrease, the risk for overfilling in primary molars.

Pulpectomies in primary incisors using three delivery systems: an in vitro study.

This in vitro study assessed the quality of pulpectomies in primary incisors using three filling systems: syringe with plastic needle syringe with metal needle, and lentulo spiral. Preoperative radiographs of sixty extracted primary incisors were taken, canals were prepared and obturated Postoperative radiographs taken in two directions were evaluated by two independent evaluators blinded to the technique used. Filling quality was determined by analyzing radiopacity, presence of voids and amount of material in the canal After statistical analysis, this study showed that NaviTip system offered a more desirable filling quality than lentulo and Vitapex syringe techniques

Smear layer production by 3 rotary reamers with different cutting blade designs in straight root canals: a scanning electron microscopic study.

OBJECTIVES: The design of the cutting blade of rotary instruments may affect the outcome of root canal instrumentation in terms of cleanliness. The aim of this scanning electron microscopic study was to compare the quality and amount of smear layer generated in the apical third of straight root canals by 2 rotary nickel-titanium reamers and 1 rotary steel reamer with different cutting blade designs. STUDY DESIGN: Seventy intact, single-rooted human mandibular premolars with straight, fully developed roots were selected for this study. Before instrumentation, the cervical portion of all teeth was removed by using a microtome (Isomet), leaving 13-mm-long roots. Automated preparation was performed with ProFile (n = 20) and Hero 642 (n = 20) reamers by using the crown-down technique and with a stainless steel engine reamer (Mani; n = 20) by using a reaming motion. All root canals were instrumented to No. 40. A control group (pulp extirpation with barbed broaches; n = 10) was also included. Irrigation with 3 mL of a 1% sodium hypochlorite (NaOCl) solution was performed after each instrumentation. After the instrumentation, each root was split longitudinally, and a scanning electron microscope was used to examine the selected areas of the canal walls at the apical third from 2 different perspectives. A 4-category scoring system for smear layer was used, and the resulting scores were statistically analyzed. RESULTS: The least smear layer remained in the Hero 642 group at the selected apical third of straight root canals (P < .05). However, all instruments left a smear layer. The surface texture of the smear layer, in addition to the depth and the frequency of packed materials into the dentinal tubules, varied with instrument type. CONCLUSION: These data revealed that the design of the cutting blade of rotary instruments can affect root canal cleanliness in straight root canals. This information may be useful in the selection of nickel-titanium rotary reamers.

Percentage of filled canal area in mandibular molars after conventional root-canal instrumentation and after a noninstrumentation technique (NIT).

AIM: To compare the percentage of filled canal area in mandibular molar roots after using conventional root-canal hand instrumentation or after a noninstrumentation technique (NIT). METHODOLOGY: Forty mandibular molars were used shortly after extraction. The root canals of 20 molars in the manual group were conventionally prepared using hand instruments and then filled with warm vertical compaction of gutta-percha. The 20 teeth in the second group were cleaned and obturated by NIT. In each case, the entire molar, including the crown and the roots, was embedded in an acrylic resin cylinder before NIT. Horizontal sections were cut at 2, 4, 6 and 8 mm from the apex. Images of the sections were taken using a microscope at x40 magnification and a digital camera; the images were scanned as Tagged Image File Format (TIFF) images into a PC. The cross-sectional area of the canal with the filling materials was measured using an image analysis programme. The percentage of filled area was calculated. The difference in the percentage of filled canal area between the two groups was analysed using a Student's t-test. RESULTS: At all levels, 93-100% of the canal area was filled in both groups. No significant difference was found between the manual technique and the NIT technique at any level (P>0.05). CONCLUSIONS: Within the limitations of this study, following the cleaning and filling of root canals using NIT, the percentage of filled root canal was similar to that using warm vertical compaction of gutta-percha after conventional root-canal instrumentation.