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Background and aims

The aim of this study was to determine the microorganisms prevalent in the necrotic dental pulp and root canals of unsuccessfully treated teeth.

Materials and methods

The present study was conducted on 150 single-rooted teeth of patients referring to a dental clinic. Sampling was performed by placing a sterile paper point in the canal for 60 s. Bacterial samples were evaluated by a microbiological technique specific for anaerobic species, used for isolation and identification of sampled strains.

Results

From the 150 samples taken, 101 were from necrotic pulps (primary infection) and 49 were from the teeth with an unsuccessful endodontic treatment (secondary infection).

Conclusion

Enterococcus faecalis was a prevalent species in the failed root canals evaluated.

Objectives:

The purpose of this study was to search samples from primary endodontic infections for the presence of two common human bacterial pathogens - Helicobacter pylori and Chlamydia pneumoniae.

Methods:

Genomic DNA isolated from samples taken from 25 root canals of teeth with asymptomatic (chronic) apical periodontitis and 25 aspirates from acute apical abscess was initially amplified by the multiple displacement amplification approach and then used as template in species-specific polymerase chain reaction (PCR) for detection of H. pylori and C. pneumoniae.

Results:

All clinical samples were positive for the presence of bacterial DNA. However, no clinical sample was positive for either H. pylori or C. pneumoniae.

Conclusions:

Neither H. pylori nor C. pneumoniae were found in samples from primary endodontic infections. These findings suggest that these species are not candidate endodontic pathogens and that the necrotic root canal does not serve as a reservoir for these human pathogens in healthy patients.

Objectives:

The aim of this study was to investigate the presence of Treponema denticola in symptomatic apical periodontitis and in symptomatic apical abscesses by real-time polymerase chain reaction (PCR) method.

Methods:

Microbial samples were collected from 60 single-rooted teeth having carious lesions and necrotic pulps. For each tooth, clinical data including patient symptoms were recorded. Teeth were categorized by diagnosis as having symptomatic apical periodontitis or symptomatic apical abscess. Aseptic microbial samples were collected using paper points from 30 infected root canals and from aspirates of 30 abscesses. DNA was extracted from the samples by using a QIAamp® DNA mini-kit and analyzed with real-time PCR.

Results:

T. denticola was detected in 24 of 30 cases diagnosed as symptomatic apical abscesses (80%), and 19 of 30 cases diagnosed as symptomatic apical periodontitis (63.3%). In general T. denticola was found in 43 of 60 cases (71.6%).

Conclusions:

Our findings suggest that T. denticola can participate in the pathogenesis of symptomatic apical abscesses.

Microorganisms infecting the dental root canal system play an unequivocal role as causative agents of apical periodontitis. Although fungi, archaea, and viruses have been found in association with some forms of apical periodontitis, bacteria are the main microbial etiologic agents of this disease. Bacteria colonizing the root canal are usually organized in communities similar to biofilm structures. Culture and molecular biology technologies have demonstrated that the endodontic bacterial communities vary in species richness and abundance depending on the different types of infection and different forms of apical periodontitis. This review paper highlights the distinctive features of the endodontic microbiota associated with diverse clinical conditions.

Context:

For successful endodontic treatment, it's imperative to locate and obturate all root canals. As concluded by Ingle, the major cause for failure of root canal therapy is in ability to recognize all theexisting canals and subsequent failure in their obturation.

Aim:

To analyze the canal configuration of the mesio-buccal root of maxillary first permanent molar teeth.

Materials and Methods:

A total of 30 recently extracted human permanent maxillary first molars were collected and stored in a container with 5% Sodium Chloride solution for four days. Teeth with open apices, external resorption, improperly formed roots and teeth with previous restorations were excluded. Using the dental modeling wax, teeth were arranged in a ‘U’ shaped arch with roots embedded inside the wax and occlusal surface remaining free. 10 teeth were arranged in each arch and three such sample plates were prepared. Flat surface of the base encasing enabled the plate to be mounted on flat plastic bite plate. With bite plate roughly centered in the focal trough area Axial, Coronal and Sagittal section Cone-Beam Computed Tomography (CBCT) images were taken with Kodak 9000 Extra-oral Imaging System. Images displayed on a monitor were inspected by two endodontists using Kodak Dental Imaging Software 3D Module V2.2.

Statistical Analysis:

When the data was observed, it was found that 24 teeth out of total 30 teeth examined showed some variation (i.e. possible additional canal) along the length of the mesio-buccal root canal. Out of these 24 teeth, 13 showed presence of additional canal at coronal third, 7 showed presence of additional canal at middle third and four showed presence of additional canal in apical third level. Percentage analysis was done as there was no group comparison to be done.

Results:

Cone-Beam Volumetric Tomography (CBVT) evaluation positively identified the variations in mesio-buccal canal in 80% of samples. Out of these, 54.16% were in coronal 3rd, 29.16% in middle 3rd and 16.66% were in apical 3rd.

Conclusion:

Within the limitations of this study, it can be concluded that- (1) more than half of maxillary first molars have four canals and (2) most of the additional canals were located in the MBR and CBVT is a good diagnostic tool to help diagnose these additional canals. Further investigations using larger sample sizes would be helpful.

INTRODUCTION

Effective debridement of the root canal system with chemical irrigants prior to obturation is the key to long-term success of endodontic therapy. The purpose of this study is to compare the antibacterial activity of 2.5% sodium hypochlorite (NaOCl) and 2% iodine potassium iodide (IKI) solutions as intracanal disinfectant in infected root canals during one-visit endodontic treatment procedure.

MATERIALS AND METHODS

Thirty single-rooted teeth with necrotic pulps in 27 patients were selected according to specific inclusion/exclusion criteria and divided into two random groups. In group I, canals were irrigated with 2.5% NaOCl during instrumentation and in group II canals were initially irrigated with sterile saline during biomechanical preparation and then exposed to a 5-minute final irrigation with 2% IKI. Bacterial samples were taken before treatment (S1), and at the end of treatment (S2). Mann-Whitney U test was used for analysis.

RESULTS

Bacteria were present in all initial samples. NaOCl was able to significantly reduce the number of colony forming units (CFU) from S1 to S2 in approximately 90% of canals. Only 15% reductions in CFUs occurred after irrigation/instrumentation in group II; this degree of disinfection was not statistically significant.

CONCLUSION

According to this study, although root canal irrigation with 2.5% NaOCl could not eradicate all bacteria within the canals; it was significantly superior in comparison with 2% IKI use.

Aims

To evaluate the microbiota of endodontic infections in deciduous teeth by checkerboard DNA-DNA hybridization after uniform amplification of DNA in samples by multiple displacement amplification (MDA).

Methodology

Forty samples from the root canal system of deciduous teeth exhibiting pulp necrosis with or without radiographically detectable periradicular/interadicular bone resorption were collected and 32 were analyzed, with 3 individuals contributing 2 samples; these were MDA- amplified and analyzed by Checkerboard DNA-DNA hybridization for levels of 83 bacterial taxa. Two outcome measures were used: the percentage of teeth colonized by each species; and the mean proportion of each bacterial taxon present across all samples were computed.

Results

The mean amount of DNA in the samples prior to amplification was 5.2 (± 4.7) ng and 6.1 (± 2.3) μg after MDA. The mean number of species detected per sample was 19 (± 4) (range: 3–66) to the nearest whole number. The most prevalent taxa were Prevotella intermedia (96.9%), Neisseria mucosa (65.6%), Prevotella nigrescens (56.2%) and Tannerella forsythia (56.2%). Aggregatibacter (Haemophilus) aphrophilus and Helicobacter pylori were not detected. P. intermedia (10%), Prevotella tannerae (7%) and Prevotella nigrescens (4.3%) presented the highest mean proportions of the target species averaged across the positive samples.

Conclusion

Root canals of infected deciduous teeth had a diverse bacterial population. Prevotella sp were commonly found with P. intermedia, Prevotella tannerae and Prevotella nigrescens among the most prominent species detected.

Combinations of bacteria isolated from the root canals of teeth with necrotic pulps and periapical bone destruction were tested for their capacity to induce abscess formation and transmissible infections when inoculated subcutaneously into guinea pigs. Transmissible infections could be induced with combinations obtained from teeth with purulent apical inflammation, but not with combinations from symptomless teeth with chronic apical inflammation. All combinations which gave transmissible infections contained strains of Bacteroides melaninogenicus or B. asaccharolyticus (formerly B. melaninogenicus subsp. asaccharolyticus). The results suggest that purulent inflammation in the apical region in certain cases may be induced by specific combinations of bacteria in the root canal and that the presence of B. melaninogenicus or B. asaccharolyticus in such combinations is essential. However, with one exception, the strains needed the support of additional microorganisms to achieve pathogenicity. The results indicate that Peptostreptococcus micros was also essential. Histological sections of the lesions in the guinea pigs showed that all bacterial combinations induced acute inflammation with an accumulation of polymorphonuclear leukocytes and the formation of an abscess. However, the presence of B. melaninogenicus or B. asaccharolyticus in the combinations resulted in a failure of abscess resolution, with a gradually increaseing accumulation of polymorphonuclear leukocytes.

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INTRODUCTION

Bacterial infection of tooth pulp can progress into periapical diseases. Root canal treatment has been established as the best treatment. In cases of failure, nonsurgical retreatment of teeth is preferred to surgical procedure and extraction.

MATERIALS AND METHODS

In this historical cohort study, 104 permanent teeth with apical lesion were treated during 2002-2008. All teeth showed radiographic evidence of periapical lesion varying in size from 1 to >10mm. A total of 55 teeth were treated with initial root canal treatment and 49 teeth required retreatment. Patients were recalled up to ≈7 years. All radiographs were taken by RSV MAC digital imaging set and long cone technique. The presence/absence of signs and symptoms and periapical index scores (PAI) were used for measuring outcome. Teeth were classified as healed (clinical/radiographic absence of signs and symptoms) or diseased (clinical/radiographic presence of signs and symptoms). The data were statistically analyzed using student t-test and Pearson chi-square or fisher’s exact test.

RESULTS

The rate of complete healing for teeth with initial treatment was 89.7%, and for retreatment group was 85.7%; there was no significant difference. Size of lesions did not significantly affect the treatment outcomes. Success of tooth treatment did not reveal significant correlation with gender and number of roots.

CONCLUSION

Orthograde endodontic treatment/retreatment demonstrates favorable outcomes. Thus, nonsurgical endodontic treatment/retreatment should be considered as the first choice in teeth with large periapical lesion.

Aim

To compare the periapical status of endodontically treated teeth between Austrian and Croatian adult patients and determine its relation to age, sex, position of teeth, and length of root canal filling.

Methods

The study was conducted from 2007 to 2009 at two university dental clinics and included 163 Croatian (412 teeth) and 101 Austrian (430 teeth) patients. We assessed the periapical status of endodontically treated teeth by using the periapical index system and determined its relation to age, sex, position of teeth, and length of root canal filling.

Results

Austrian patients had a greater number of diseased endodontically treated teeth than Croatian patients (P = 0.001). In the age group 31-40 years, Austrian patients had apical periodontitis significantly more often (22.1% vs 12.2%, P < 0.001) than Croatian patients. In relation to sex and position of teeth, no significant difference was found between the two groups. In Croatian patients, apical periodontitis was significantly more often present in molar than premolar (46.2% vs 29.7%, P = 0.022) and front teeth (46.2% vs 24.1%, P < 0.001). In Austrian patients, apical periodontitis was significantly more often present in molar and premolar than front teeth (molar-front teeth: 38.2% vs 25.5%, P = 0.011; premolar-front teeth: 36.3% vs 25.5%, P = 0.029). Croatian and Austrian patients significantly differed in the number of adequately filled and underfilled teeth with AP (both P<0.001).

Conclusion

Apical periodontitis was significantly more present in endodontically treated teeth in Austrian patients. The difference in the periapical status between Croatian and Austrian patients was most related to age and length of root canal filling.

To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis. Patients with apical periodontitis who were referred for endodontic retreatment were examined. The type and quality of the restoration, symptoms, quality of obturation were recorded. During retreatment, an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E. faecalis. The 16S rRNA technique was used to identify E. faecalis. A total of 32 women and 22 men (mean age: 38 years; s.d.: 11 years) and 58 teeth were studied. The prevalence of E. faecalis was 19% in the saliva and 38% in the root canals. The odds that root canals harbored E. faecalis were increased if the saliva habored this bacterium (odds ratio=9.7; 95% confidence interval=1.8–51.6; P<0.05). Teeth with unsatisfactory root obturation had more cultivable bacterial species in root canals than teeth with satisfactory root obturation (P<0.05). E. faecalis is more common in root canals of teeth with apical periodontitis than in saliva. The prevalence of E. faecalis in root canals is associated with the presence of E. faecalis in saliva.

Dental trauma generally requires multidisciplinary planning and treatment for good prognosis. When immature teeth are traumatized to a degree where pulp necrosis ensues, the objective of root canal treatment should be apexogenesis and root maturation. Apexification of the root is the conventional choice, which involves cleaning the canal and filling it with a temporary medication that stimulates the formation of a calcific apical barrier. Dental Trauma Service of Piracicaba Dental School, State University of Campinas (UNICAMP), Brazil employs a dressing for apexification treatments with calcium hydroxide, chlorhexidine gel 2% and zinc oxide. This paper reports the case of a dental trauma of the maxillary central incisors and subluxation on teeth 11, 12 and 21 that were treated with multidisciplinary collaboration (Endodontics, Periodontology and Operative Dentistry) to improve prognosis. After five-years there were no pathological conditions and the teeth showed every evidences of success.

Objectives:

Using the fluid filtration method, an in vitro study was conducted to evaluate the effects of medication with calcium hydroxide on the sealing ability of the New Endodontic Cement (NEC) apical barrier in the short and long terms.

Methods:

Fifty extracted single rooted teeth were prepared and apical resorption produced using acid sulfuric for four days. The teeth were randomly divided into two experimental groups (n=20) and two control groups. In group 1, calcium hydroxide was placed into all canals for one week and in group 2, no medication was used. In both groups, a 4 mm NEC apical plug was placed in the canals and the remaining portion of the canals was filled with gutta-percha. The amount of microleakage of all samples was evaluated after one week and three months. The data were statistically analyzed using two-way ANOVA.

Results:

There was no significant difference between the two groups in either time period (P>.05). In both group 1 and group 2, microleakage increased after three months but this increase was not statistically significant (P>.05).

Conclusions:

According to the result of this study, medication with calcium hydroxide had no adverse effect on the short- and long-term sealing properties of an NEC apical plug.

Objectives

To investigate the expression of matrix metalloproteinases (MMPs) in apical periodontitis and during the periapical healing phase following root canal treatment.

Methods

Apical periodontitis was induced in dog teeth and root canal treatment was performed in a single visit or using an additional calcium hydroxide root canal dressing. One hundred and eighty days following treatment the presence of inflammation was examined and tissues were stained to detect bacteria. Bacterial status was correlated to the degree of tissue organization, and to further investigate molecules involved in this process, tissues were stained for MMP-1, MMP-2, MMP-8, and MMP-9. Data were analyzed using one-way ANOVA followed by Tukey test or Kruskal-Wallis followed by Dunn.

Results

Teeth with apical periodontitis that had root canal therapy performed in a single visit presented an intense inflammatory cell infiltrate. Periapical tissue was extremely disorganized, and this was correlated with the presence of bacteria. Higher MMP expression was evident, similar to teeth with untreated apical periodontitis. In contrast, teeth with apical periodontitis submitted to root canal treatment using calcium hydroxide presented a lower inflammatory cell infiltrate. This group had a moderately organized connective tissue, a lower prevalence of bacteria, and a lower number of MMP-positive cells, similar to healthy teeth submitted to treatment.

Conclusion

Teeth treated with calcium hydroxide root canal dressing exhibited a lower percentage of bacterial contamination, a lower MMP expression, and a more organized ECM, unlike those treated in a single visit. This suggests that calcium hydroxide may be beneficial in tissue repair processes.

INTRODUCTION

This cross-sectional survey determined the dental prevalence of apical periodontitis (AP) in selected Iranian population, and evaluated the influence of the quality of root canal treatment (RCT) and their coronal restorations (CR) on the periapical status.

MATERIALS AND METHODS

A total of 1064 panoramic radiographies were evaluated by two observers during 2009. The quality of RCT i.e. length/density of root fillings and CR in addition to periapical status of endodontically treated teeth were recorded. Their interrelationship was analyzed by Chi-squared, logistic regression and Spearman's rho statistics. Hosmer and Lemeshow tests were used for assessing fitness of logistic regression model and one sample k-s test was used for evaluating of normality of the data.

RESULTS

Our results showed that 527 teeth (52%) of the endodontically treated teeth presented with AP radiographically. The percentages of teeth which fulfilled the criteria of an acceptable RCT or CR radiographically were 42.3 and 62.5 respectively. Incidence of AP among teeth with acceptable RCT (29.1%) was significantly lower than those suffering from unacceptable RCT (68.8%) (P<0.001). Moreover, adequate CR demonstrated a significantly better periapical status (58.6%) compared to teeth with inadequate CR (30.3%) (P<0.001). The incidence of AP ranged from 25.6% (good qualities) to 79.5% (bad qualities) (P<0.001). Cases with both unacceptable RCT/CR were 11 times more likely to have AP than cases with acceptable RCT/CR. The quality of RCT and CR were found to impact the periapical health of endodontically treated teeth.

CONCLUSION

There are a significant high number of technically unacceptable endodontic and restorative treatments in Iran; therefore considerable efforts are needed to improve the standards of endodontic and restorative treatments.

Objectives

The aim of this study was to investigate the presence of Enterococcus faecalis in endodontic infections in both deciduous and permanent teeth by culture and polymerase chain reaction (PCR) methods.

Methods

A total of 145 children aged 5–13 years old were involved in this study. The presence of E. faecalis in necrotic deciduous and permanent teeth root canals was studied using culture and polymerase chain reaction methods.

Results

Among 145 molar teeth, 57% (n=83) presented necrotic asymptomatic pulp tissues and were included in this study. Culture and PCR methods detected the test species in 18 and 22 of 83 teeth involved, respectively. E. faecalis was cultured from 8 (18%) of 45 necrotic deciduous teeth and from 10 (26%) of 38 necrotic permanent teeth. PCR detection identified the target species in 10 (22%) and 12 (32%) of necrotic deciduous and permanent teeth respectively. Statistically significant difference in the presence of E. faecalis in deciduous and permanent teeth was found by culture and PCR methods (P=0.03 and 0.02, respectively). The difference in the presence of E. faecalis between two different methods was not statistically significant (P>.05).

Conclusions

The results of the present study confirm that both culture and PCR methods are sensitive to detect E. faecalis in root canals.

Samples from infected root canals of 43 teeth with chronic apical periodontitis were analyzed for the presence and relative levels of 83 oral bacterial species and/or phylotypes using a reverse-capture checkerboard hybridization assay. Associations between the most frequently detected taxa were also recorded. The most prevalent taxa were Olsenella uli (74%), Eikenella corrodens (63%), Porphyromonas endodontalis (56%), Peptostreptococcus anaerobius (54%), and Bacteroidetes oral clone X083 (51%). When prevalence was considered only for bacteria present at levels >105, Bacteroidetes clone X083 was the most frequently isolated bacterium (37%), followed by Parvimonas micra (28%), E. corrodens (23%), and Tannerella forsythia (19%). The number of target taxa per canal was directly proportional to the size of the apical periodontitis lesion, with lesions >10 mm in diameter harboring a mean number of approximately 20 taxa. Several positive associations for the most prevalent taxa were disclosed for the first time and may have important ecological and pathogenic implications. In addition to strengthening the association of several cultivable named species with chronic apical periodontitis, the present findings using a large-scale analysis allowed the inclusion of some newly named species and as-yet-uncultivated phylotypes in the set of candidate pathogens associated with this disease.

Aim

To determine the prevalence of apical periodontitis and assess the quality of endodontic fillings in the population of the city of Zagreb, Croatia.

Methods

A total of 1462 orthopantomograms from new patients at 6 different dental practices was analyzed during 2006 and 2007. The presence of periapical lesions was determined by using the periapical index score (PAI). The quality of endodontic fillings was assessed according to the filling length and homogeinicity. Data were analyzed using t test and ANOVA with Scheffe post-hoc test.

Results

There were 75.9% of participants with endodontically treated teeth and 8.5% of all teeth were endodontically treated. Only 34.2% of endodontically treated roots had adequate root canal filling length, while 36.2% of root canal fillings had homogenous appearance. From the total number of teeth with intracanal post, 17.5% had no visible root canal filling. Using PAI 3 as a threshold value for apical periodontitis, periapical lesions were detected in 8.5% of teeth. Adequate quality of root canal fillings was associated with a lower prevalence of periapical lesions.

Conclusion

We found a large proportion of endodontically treated teeth with apical periodontitis and a correlation between the quality of endodontic filling and the prevalence of periapical lesions. This all suggests that it is necessary to improve the quality of endodontic treatment in order to reduce the incidence and prevalence of apical periodontitis.

Crown fractures are common detrimental consequences of dental traumatic injuries. Early management of such cases is mandatory in order to prevent subsequent pathological changes that could further complicate the treatment. Pulp necrosis, chronic and cystic apical periodontitis can be the fate if these teeth are left untreated. Despite these serious complications, root canal treatment followed by apical surgery is considered a valid treatment option when such cases become complicated with large periapical lesions. However, whether a retrograde filling is essential to be placed or not is still a matter of debate. This case report discusses the orthograde endodontic management, the surgical approach and the clinical outcomes of longstanding crown fractured teeth with large cyst-like periapical lesions with and without retrograde filling.

Endodontic infections have been traditionally studied by culture methods, but recent reports showing that over 50% of the oral microbiota is still uncultivable (B. J. Paster et al., J. Bacteriol. 183:3770-3783, 2001) raise the possibility that many endodontic pathogens remain unknown. This study intended to investigate the prevalence of several uncultivated oral phylotypes, as well as newly named species in primary or persistent endodontic infections associated with chronic periradicular diseases. Samples were taken from the root canals of 21 untreated teeth and 22 root-filled teeth, all of them with radiographic evidence of periradicular bone destruction. Genomic DNA was isolated directly from each sample, and 16S rRNA gene-based nested or heminested PCR assays were used to determine the presence of 13 species or phylotypes of bacteria. Species-specific primers had already been validated in the literature or were developed by aligning closely related 16S rRNA gene sequences. Species specificity for each primer pair was confirmed by running PCRs against a panel of several oral bacteria and by sequencing DNA from representative positive samples. All species or phylotypes were detected in at least one case of primary infections. The most prevalent species or phylotypes found in primary infections were Dialister invisus (81%), Synergistes oral clone BA121 (33%), and Olsenella uli (33%). Of the target bacteria, only these three species were detected in persistent infections. Detection of uncultivated phylotypes and newly named species in infected root canals suggests that there are previously unrecognized bacteria that may play a role in the pathogenesis of periradicular diseases.

Background

Despite numerous studies on the prevalence of apical periodontitis (AP) and endodontic treatment in diverse geographical populations, there are currently no data on the prevalence of these conditions in populations of adults native to Kosovo. Therefore, little is known about how widespread these conditions are, and whether there is any correlation between root canal treatment and AP. The purpose of our research was to address this anomaly by investigating AP and endodontic treatment in an adult Kosovar population based on radiographic examination.

Methods

The sample used for this study consisted of randomly selected individuals referred to the University Dentistry Clinical Center of Kosovo in the years 2006-2007. Orthopantomographs of 193 patients were evaluated. The periapical status of all teeth (with the exception of third molars) was examined according to Ørstavik's Periapical Index. The quality of the root canal filling was rated as 'adequate' or 'inadequate' based on whether all canals were filled, the depth of fill relative to the radiographic apex and the quality of compaction (absence/presence of voids). Data were analyzed statistically using the Chi-square test and calculation of odds ratios.

Results

Out of 4131 examined teeth, the prevalence of apical periodontitis (AP) and endodontic treatment was 12.3% and 2.3%, respectively. Of 95 endodontically-treated teeth, 46.3% were associated with AP. The prevalence of AP increased with age. The prevalence in subjects aged over 60 years old (20.2%) was higher than in other age groups. A statistically significant difference was found for the frequency of endodontically-treated teeth associated with AP in the 40-49 year age group (P < 0.001). Of some concern was the discovery that only 30.5% of the endodontically-treated teeth examined met the criteria of an acceptable root canal filling. Inadequately root-filled teeth were associated with an increased AP risk.

Conclusions

The prevalence of AP and the frequency of endodontically-treated teeth with AP in this Kosovar population are higher than those found in other countries. Inadequate root canal fillings were associated with an increased prevalence of AP.

INTRODUCTION

Intrinsic tooth discolorations after endodontic treatment are principally attributed to the composition of necrotic pulp tissue, hemorrhage within the pulp cavity, endodontic medicaments and/or filling materials. Residual sealer left in pulp chamber after obturation can cause discoloration. The objective of this in vitro study was to evaluate coronal discoloration created by AH26 and ZOE sealers after four months.

MATERIALS AND METHODS

Fifty intact human extracted maxillary central incisors were employed. Access cavities were prepared in all samples and root canals were instrumented; coronal orifices were then sealed using self-cure glass ionomer. The teeth were divided into two experimental groups (n=20) according to utilized sealer in pulp chambers including AH26 and Dorifill (ZOE). The remaining 10 teeth served as negative and positive controls (n=5). The access cavities were sealed with self-cure glass ionomer. Teeth were kept in incubator for four month. Preliminary digital images of the teeth were taken and then compared with those related to 4-month follow-up. The images were assessed using Photoshop software. Data was analyzed using paired t-test and independent samples t-test.

RESULTS

The teeth which were filled with AH26 sealer showed significantly greater discoloration than those filled with ZOE sealer (Dorifill) (P<0.05).

CONCLUSION

AH26 sealer causes greater discoloration of the crown compared to ZOE sealer. Despite the other disadvantage of AH26 sealer, it seems that Dorifill is more esthetically considerate.

Some clinical case reports have shown that immature permanent teeth with periradicular periodontitis or abscess can undergo apexogenesis after conservative endodontic treatment. A call for a paradigm shift and new protocol for the clinical management of these cases has been brought to attention. Concomitantly, a new population of mesenchymal stem cells residing in the apical papilla of permanent immature teeth recently has been discovered and was termed stem cells from the apical papilla (SCAP). These stem cells appear to be the source of odontoblasts that are responsible for the formation of root dentin. Conservation of these stem cells when treating immature teeth may allow continuous formation of the root to completion. This article reviews current findings on the isolation and characterization of these stem cells. The potential role of these stem cells in the following respects will be discussed: (1) their contribution in continued root maturation in endodontically treated immature teeth with periradicular periodontitis or abscess and (2) their potential utilization for pulp/dentin regeneration and bioroot engineering.

Aim. The aim of this study was to evaluate by means of radiographs the technical quality of root fillings performed by dental practitioners. Methods and Material. Standardized periapical radiographs were made on 484 patients who received endodontic treatment in private practice. A total of 831 endodontically treated teeth with 1448 roots were evaluated for technical quality of the root canal filling and the periapical status of the teeth. Also, the apical status of each root-filled tooth was assessed according to the length, density, and taper of root fillings, and the presence of apical transportation, broken root instruments, and overfilled sealer or gutta-percha material was recorded for each root canal. Results. Of the endodontically treated teeth 26.6% had healthy periapical tissues, while technically good endodontic treatment constituted 12.8%. Based on the treatment success, there was no significant difference between the tooth groups. Statistical analysis of the data did not demonstrate statistically significant differences between the various parameters that were evaluated (P < 0.05). Conclusions. Technical quality of root fillings in a population who received treatment in private practice was poor and was consistent with a low prevalence of apical health. The probable reasons for this failure are multifactorial and may be improved if the operators improve their skills with continuing postgraduate education programs.

A large proportion of the population have pulpless teeth, hence the importance of this subject. The main principles concerned in the treatment of pulpless teeth are: the removal of the pulp in its entirety, the drainage of the stump of the severed pulp, the cleansing and drying of the root canals and the filling of the tooth cavity.

Local anæsthesia is preferable to caustics for desensitizing the tooth pulp prior to its removal. Antiseptics used in a dry condition are preferable to those used in a moist condition for root canal treatment.

Nothing is gained by filling the root canals, if the peri-apical tissues have scarred there is no further discharge into these canals; and if they have not scarred the filling of the root canals will only obstruct drainage. If the discharge from the canals is copious, the tooth cavity should be left open to the mouth except for the insertion of a loosely placed dressing.

Untreated pulpless teeth are more liable to give rise to “open” sepsis; treated pulpless teeth to “closed” sepsis.

The crux of the question as to whether pulpless teeth should be retained or extracted is one of evaluating their advantages and disadvantages.

A tooth deprived of its pulp owing to infective changes gives rise to subjective and objective symptoms and signs.

A tooth deprived of its pulp owing to physiological changes gives rise to no apparent ill effects.

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