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Results for “Tooth Apex”

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PubMed2001

Size discrepancy of apical bases and treatment success in angle Class III malocclusion.

The aim of this retrospective clinical study was to measure the apical bases and determine their size relationship in Class III malocclusion cases before and after orthodontic treatment, in order to evaluate their significance for the treatment success. Maxillary and mandibular apical bases were measured on study models of 104 Class III cases treated by conventional orthodontics, using a specifically constructed conveyance apparatus, and related to each other as an index. Treatment success was quantitatively assessed as the percentage change of PAR scores obtained from the pretreatment and posttreatment study models. Statistically significant relationships were disclosed between the measurements of the apical bases and several other evaluated parameters. The results obtained indicate a high prognostic value of the size relationship of the apical bases for the treatment success of Class III malocclusion.

Adolescent↗

PubMed2005

Age estimation in children by measurement of open apices in teeth.

This paper concerns a method for estimating the age of children based on their teeth. The sample consisted of 455 Italian white children (213 boys, 242 girls) aged between 5 and 15 years. The purpose of the present investigation was to present a method for assessing chronological age based on the relationship between age and measurement of the open apices in teeth. Pearson's correlation coefficients between age and these variables showed that the correlations between age and the open apices in teeth were significant and negative. Furthermore, gender and the number of teeth with the apical end of the root canals completely closed (N(0)) showed a significant correlation with chronological age. With the aid of a stepwise multiple regression model, a linear relationship between open apices, N(0), and age was shown. Statistical analysis indicated that these morphological variables explain 83.6% of the variations in estimated chronological age. The median of residual errors between the actual and estimated ages was -0.035 years [interquartile range (IQR)=1.18 years].

Adolescent↗

PubMed2003

Apical leakage in maxillary type IV premolars with three different endodontic treatments.

The aim of this study was to evaluate the sealing ability in orthogradely filled, apicoectomised and retrogradely filled maxillary premolars with two canals and two separate apical foramina. The root canals of 51 extracted maxillary premolars of type IV were uniformly shaped and filled by means of lateral condensation and subsequently randomly divided into three groups of 17 teeth each. The teeth of groups II and III received an apicoectomy. In group III an additional retrograde seal (Ketac Fil) was applied. Group I served as control. All specimens were immersed in a methylene blue solution for 24 h. The teeth were cross-sectioned and the maximal dye-penetration was measured. The significantly least dye-penetration was observed in group II (apicoectomy only), followed by group I and group III. The differences among all groups were statistically significant (p<0.05). Most of the retrograde restorations in group III revealed circular colouration around the retrograde fillings extending to the gutta percha. Although the teeth of group II revealed the least dye-penetration, an apicoectomy cannot be favoured against an endodontic retreatment in maxillary premolars of type IV. The application of retrograde fillings using Ketac Fil must be considered critically.

Apicoectomy↗

PubMed2004

Appearance of the root canal walls after preparation with NiTi rotary instruments: a comparative SEM investigation.

The aim of this study was to evaluate, in vitro, with scanning electron microscope (SEM), the appearance of root canal walls shaped by three different rotary NiTi techniques and one conventional manual technique in human extracted teeth. Four different instruments were used: K3, Hero 642, RaCe and K-file. Each sample was irrigated with 5 ml of 5% NaOCl and 5 ml of 3% H2O2 and EDTA, Rc-Prep (1 ml). Each sample was prepared for SEM observation and analyzed in the coronal, middle and apical third, comparing its aspect with a predefined scale of four different parameters: presence of smear layer, pulpal debris, inorganic debris and surface profile. The apical third showed significantly more pulpal and inorganic debris, smear layer and a high number of surface profile irregularities. No significant difference was found at the coronal, middle and apical thirds between manual and rotary techniques for inorganic debris, smear layer and surface profile. Much pulpal debris were found in the apical third for K3 and RaCe compared with Hero 642 and K-file. In conclusion, mechanical rotary techniques with NiTi instruments produced quite similar results compared with a conventional manual technique using K-files. The present study demonstrated that dentin and pulpal debris, the morphology of smear layer and surface profile were only partially influenced by the type of endodontic instruments. The apical third was the anatomical area with greater amount of debris and smear layer.

Analysis of Variance↗

PubMed2006

Electronic root canal length measurement before and after experimentally induced pulpitis and apical periodontitis in dogs.

The aim of the study was to examine the influence of the state of the pulp and apical periodontium on the results of electronic root canal length measurement (ERCLM) with a resistance measuring device in dogs. Pulpitis and apical periodontitis were induced by pulp exposure and contamination by the oral flora in the premolar teeth of six mongrel dogs, comprising four experimental groups (36 root canals). In a control group, measured lengths of teeth with uninfected pulps were performed on the first experimental day (44 root canals). In all animals the ERCLMs were performed on teeth with healthy pulps, and at the end of the experimental period (20, 35, 50 and 65 days) following pulp exposure. The point of measuring canal lengths was the anatomical obstacle above the apical delta. Electronically measured lengths (EML) were compared between each other and with the root canal length established by tactile-sense measurement verified radiographically. The EMLs were less accurate in teeth with healthy pulps and teeth with pulpitis in the third experimental group (dif=2.27 x 2.65 mm(2); t test, p<0.05), while they were most precise after 65 days in teeth with completely necrotic pulp and established chronic apical periodontitis (dif=0.54 x 1.36 mm(2); t test, p>0.05). These results suggest that the state of the pulp and periapical tissue may have an influence on the ERCLM.

Animals↗

PubMed2005

Endoscopic periradicular surgery: a prospective clinical study.

We did apicectomies of 30 teeth with periradicular lesions in 23 patients, using a 3 mm endoscope. Two patients failed to attend for postoperative assessment and of the remaining 21 patients who had 28 teeth treated the operation was judged after 1 year to be a success in 26 (93%).

Adult↗

PubMed2004

The LightSpeed system.

This article describes the use of an innovative, engine-driven, rotary, root canal preparation instrument. The geometric design of this nickel-titanium instrument is totally different from currently marketed manual or engine-driven stainless steel or nickel-titanium instruments. The thin, taperless, noncutting shafts of LightSpeed instruments maximize the flexibility of the nickel-titanium alloy, particularly in the larger sizes. The three different methods for using the LightSpeed cutting heads and three different methods for using the LightSpeed system are described. LightSpeed instruments enable larger apical preparations in curved canals with less coronal flaring than is possible with most other techniques.

Dental Alloys↗

PubMed2004

The K3 rotary nickel-titanium file system.

The K3 rotary nickel-titanium file system by SybronEndo is a state-of-the-art rotary nickel-titanium endodontic instrumentation method combines excellent cutting characteristics with a robust sense of tactile control and excellent fracture resistance. The K3 has universal applicability across a wide range of clinical indications. Although it is a complete instrumentation system, future possibilities for hybrid instrumentation techniques that combine the best features of K3 with other rotary system hold promise.

Dental Alloys↗

PubMed2004

The hybrid concept of nickel-titanium rotary instrumentation.

The idea of the hybrid concept is to combine instruments of different file systems and use different instrumentation techniques to manage individual clinical situations to achieve the best biomechanical cleaning and shaping results and the least procedural errors. The hybrid concept combines the best features of different systems for safe, quick, and predictable results. Several hybrid instrumentation sequences are presented and their limitations are discussed.

Dental Alloys↗

PubMed2004

Real World Endo Sequence File.

As a result of the quest for a better, simpler technique, Real World Endo in partnership with Brasseler USA has developed a new endodontic file and sequence. It is hoped that this file and sequence will satisfy many of the current demands of modern root canal therapy and be user friendly. This article discusses the benefits of a fully tapered preparation, the general design of rotary files, and the specific design and use of Real World Endo Sequence File.

Dental Alloys↗

PubMed2004

MicroSeal systems and modified technique.

The MicroSeal technique was introduced in 1996 and consists of a nickel-titanium (NiTi) spreader, a NiTi condenser, a gutta percha heater, a gutta percha syringe, and a special formulation of gutta percha available in cones or in cartridges. It is considered a thermomechanical compaction technique that uses a rotary instrument to plasticize the gutta percha and move it within the root canal apically and laterally. The MicroSeal technique together with the author's modifications may be a very important tool in the hands of the endodontist. The MicroSeal system is able to preserve a conservative preparation and provide an adequate penetration by the obturation instruments in the apical third. Knowledge of the technique's indications and limitations represents an important step in the learning curve for those practitioners who are willing to incorporate a new obturation method into their clinical techniques.

Dental Alloys↗

PubMed2004

Perforation repair and one-step apexification procedures.

As with any dental treatment, procedural mishaps can occur during root canal therapy. One such occurrence is the perforation of a root or pulpal floor. After a perforation occurs, the goals are to "sterilize" (decontaminate) the site and then seal the perforation. The material most widely used in endodontics to seal perforations is mineral trioxide aggregate (MTA). MTA us extremely biocompatible, and it has been shown historically that osteoidlike material grows right into MTA. The technique of one-step apexification offers an alternative to draw-out cases with several medicament-changing appointments that often result in a failed attempt at root-end closure. With the favorable histologic response of MTA, this material is the best current choice for this procedure. Completion of these cases in an effective and efficient way allows for permanent restorations to be done in a more timely manner, prolonging the longevity of these teeth.

Aluminum Compounds↗

PubMed2004

Endodontic working width: current concepts and techniques.

Root canal morphology is a critically important part of conventional and surgical endodontics (root canal therapy). Many in vitro studies have recorded the scales and average sizes of root canals, but there have been few clinical attempts to determine the working width. In the absence of a study that defines what the original width and optimally prepared horizontal dimensions of canals are, clinicians are making treatment decision without any support of scientific evidence. This article provides definitions and perspectives on the current concepts and techniques to handle working width-the horizontal dimension of the root canal system-and its clinical implications.

Dental Pulp↗

PubMed2006

The effect of silane on the bond strengths of fiber posts.

OBJECTIVES: Esthetic posts have been developed to maximize the foundation of esthetic restorations. The purpose of this study was to evaluate the effect of silane on the bond strength of three fiber-reinforced resin posts (fiber posts). METHODS: Fifty-four extracted human maxillary central incisors and canines were endodontically treated. D.T. Light Post (DT, Bisco), FRC Postec (FR, Ivoclar Vivadent), and ParaPost Fiber White (PP, Coltène/Whaledent) were inserted using the resin adhesive system provided by the respective manufacturer. For half of the specimens in each group, the fiber posts were treated with a silane solution (Monobond S, Ivoclar Vivadent). A push-out test was performed on three different sections of each root to measure bond strengths. Data were analyzed with ANOVA and Bonferroni's post hoc test at P<0.05. RESULTS: The use of silane did not result in any statistically significant difference at any level of the root. Silane did not result in any significant different bond strengths (MPa) for each of the posts. When the data were pooled, the use of silane did not result in statistically significant different bond strengths at P>0.403: No silane=12.7+/-8.4; Silane=14.1+/-7.0. The coronal third of the root (17.5+/-6.7) resulted in statistically greater bond strengths than the medium third (12.9+/-6.8) and than the apical third (9.8+/-7.3) at P<0.002 and P<0.0001, respectively. The medium third and the apical third resulted in no statistically significant different bond strengths from each other at P>0.07. The type of post did not result in statistically significant different bond strengths at P>0.417: DT=14.7+/-6.8 MPa; FR=13.3+/-6.6 MPa; PP=12.2+/-6.6 MPa. SIGNIFICANCE: The use of a silane coupling agent did not increase the push-out bond strengths of the three fiber posts used in this study. All posts bonded to root dentin at the same magnitude. Bonding is more predictable at the most coronal level of the root.

Bismuth↗

PubMed2004

Risk analysis of failure of root canal treatment for teeth with inaccessible apical constriction.

OBJECTIVE: The risk of failure of root canal therapy was assessed in teeth with inaccessible apical constriction and factors influencing treatment outcome in these teeth were analyzed. METHODS: From the same 57 patients, one tooth with inaccessible apical constriction (n=57) and one tooth with adequate accessibility (n=57) were included in this retrospective investigation. Cox regression analysis was used to analyze factors that may have influenced the outcome one or more years after obturation. These factors included inaccessibility, systemic disease, canal curvature, preoperative periradicular lesion, widening of periodontal ligament space, patient gender and age, size of master apical file, preoperative pulp vitality, years of operator experience and obturation length. RESULTS: Inaccessible apical constriction was a significant factor related to outcome (odds ratio, 5.301). Preoperative presence of periradicular lesion significantly influenced the outcome in cases with inaccessibility (odds ratio, 4.448). CONCLUSION: Inaccessibility increases the risk of root canal therapy failure particularly in teeth with preoperative periradicular lesion.

Adult↗

PubMed2006

The effect of exposure to irrigant solutions on apical dentin biofilms in vitro.

This study assessed the effectiveness of different concentrations of sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX) (Vista Dental Products, Racine, WI), and BioPure MTAD (Dentsply Endodontics-Tulsa Dental, Tulsa, OK). Intracanal contents were collected from 10 patients diagnosed with chronic apical periodontitis. The samples were cultured on hemisections of root apices to generate a polymicrobial biofilm. Each biofilm was separately immersed in 6% NaOCl, 3% NaOCl, 1% NaOCl, 2% CHX, 1% NaOCl followed by BioPure MTAD, and sterile phosphate buffered solution (PBS). SEM analysis showed 6% NaOCl and 3% NaOCl were capable of disrupting and removing the biofilm; 1% NaOCl and 1% NaOCl followed by MTAD were capable of disrupting the biofilm, but not eliminating bacteria; 2% CHX was not capable of disrupting the biofilm. Viable bacteria could not be cultured from specimens exposed to 6% NaOCl, 2 % CHX, or 1% NaOCl followed by BioPure MTAD. These results indicate that 6% NaOCl was the only irrigant capable of both rendering bacteria nonviable and physically removing the biofilm.

Biofilms↗

PubMed2006

The quantitative evaluation of apical sealing of four endodontic sealers.

The aim of this in vitro study was to evaluate the apical seal obtained with four root canal sealers: Rocanal 2, Sealapex, AH Plus, and RC Sealer. Forty root canals were prepared using the step-back technique. The specimens were divided into four groups of 10 samples and obturated by laterally condensed gutta-percha with one of the tested sealers. The computerized fluid filtration method was used for evaluation of apical sealing properties. The quantitative apical leakage of each specimen was measured after 7, 14, and 21 days. Statistical analysis indicated that the apical leakage of all sealers used in this study decreased gradually from 7 days to 21 days (p < 0.05). Sealapex showed better apical sealing than the other sealers at 7, 14, and 21 days (p < 0.05). RC Sealer, AH Plus, and Rocanal 2 showed similar apical leakage values at every period (p > 0.05).

Analysis of Variance↗

PubMed2006

Penetration depth of warm vertical Gutta-Percha pluggers: impact of apical preparation.

The warm vertical gutta-percha compaction technique requires canals to be sufficiently flared to allow the tip of the plugger to penetrate to the apical third. The aim of the present study was to determine whether apical preparation or finishing instruments could be used to improve the penetration depth of pluggers. Single-root canals (48) were prepared using different rotary Ni-Ti instruments: M File System (I), ProTaper (II), HEROShaper (III), and EndoK3 (IV). Finger and heat (Endotwinn) pluggers were introduced into the canals, one after the other, and their penetration depths were measured. The apical thirds of the canals were then flared with specific instrumentation and the penetration depths of the pluggers were once again measured. After the initial preparation, the smallest diameter pluggers (No. 1 and F) could be inserted 5 to 7 mm short of working length without difficulty. Apical flaring improved the maximum penetration depth of the finger plugger by 1.76 mm and the heat plugger by 1.52 mm The deepest penetration was obtained with the EndoK3, ProTaper, and HEROShaper instruments. By accentuating the taper, apical flaring facilitated the penetration of warm vertical gutta-percha compaction pluggers.

Dental Alloys↗