Force eruption of mandibular second incisor in an 11- year old boy: a technical report

There is a great challenge in the treatment of deeply fractured and un-restorable teeth among dentists. Orthodontic force eruption is a method of treatment for these teeth to preserve natural root system and periodontal structures. This technical report is a new modification of this procedure presented in an 11- year old boy with deeply fractured left second mandibular incisor. The fractured teeth were treated with root canal therapy and a file #80 was modified to become a hook cemented into the fractured tooth Anterior teeth were splinted and used as anchorage to help the root extrusion. 1-year follow up of the tooth showed the convenience of the treatment. This simple and low-cost method can be an acceptable alternative to the current high cost techniques, achieving the same results

Prevalence of root dilaceration in adult patients referred to shiraz dental school [2005-2010]

Statement of Problem: Dilaceration is defined as a sudden change in the axial inclination of root or between the crown and the root of a tooth

There is no previous study evaluating its prevalence in south of Iran

Purpose: This study evaluates the prevalence of root dilaceration on the basis of its location in dental arch in a sample of dental patients referring to Shiraz dental school, Iran

Materials and Method: This retrospective study was performed using full mouth periapical radiographs of 250 patients who were referred to Shiraz dental school

Buccal and lingual dilaceration was determined by its known" bull's eye" appearance in the radiographs or if the deviation was in the mesial or distal directions; the angle of 90 degree or greater between the deviation and the axis of root was the inclusion criteria

Results: Root dilaceration was detected in 0.3% of teeth and 7.2% of patients. It was distributed equally between the maxilla and mandible. Mandibular second molar was the most frequent dilacerated tooth [1.6%] followed by maxillary first molar [1.3%] and mandibular first molar [0.6%]

The alveolar nerve was the most common anatomic structure near dilacerated teeth

Conclusion: According to this study, root dilaceration is an uncommon developmental anomaly which occurs mostly in the posterior teeth

Comparison of apical sealing ability of lateral condensation technique in room and body- simulated temperatures [an in vitro study]

Statement of Problem: Studies reported that nearly 60% of endodontic failures have been attributed to inadequate obturation of the root canal system. Thus, complete obturation of the root canal system and proper apical seal are essential elements in the longterm success of root canal treatment

Purpose: This study aimed to compare the apical seal of lateral condensation technique in the room and in body- simulated temperature

Materials and Method: In this experimental study, 70 extracted, single- rooted, human premolar teeth were instrumented and divided up into four groups. All tooth's canals were obturated by lateral condensation technique except the teeth in the positive control group. Group 1 and 2, each with 30 teeth, were obturated in the room and intracanal temperature respectively. The other two groups were positive and negative control group each with 5 teeth. All groups except negative control were covered by two layers of nail polish. Then linear dye penetration was evaluated with a stereomicroscope. Data was analyzed with student-t test and also Kolmogorov- Smirnov Goodness- of- Fit test to make sure of data

Results: Results showed that dye penetration in group one [obturation in room temperature] was 0.6mm more than group 2 [obturation in simulated-body temperature] although this was not statistically significant [p> 0.05]

Conclusion: Under the condition of this invitro study, apical sealing ability was better in the body-simulated temperature than the room temperature, although it was not statistically significant

Comparison of MTA and CEM cement microleakage in repairing furcal perforation, an in vitro study

Statement of Problem: Sealing the perforation defect is an important factor to reduce inflammation in the area and to perform healing. Selecting the appropriate material to repair the defect is an important concern. Among the various available materials, MTA and CEM are used recently for achieving this purpose. In the current study we compare the sealing ability of these materials by evaluating their microleakage by fluid filtration method

Purpose: The purpose of this study was to compare the microleakage of MTA and CEM cement in furcal perforation in different periods of time

Materials and Method: Forty one mandibular molars were selected for this experimental study. The perforation defects were created perpendicular to the long axis of the teeth, on the furcation of the teeth and the samples were divided into 2 experimental and two control groups. The defects were sealed by CEM and MTA in each experimental group. The samples were undergone the fluid filtration test with 20 cm H2O pressure. The amount of fluid filtration was measured for each sample at 24, 72 and 168 hrs and the data were analyzed by using ANOVA and T test

Results: The experimental groups which were sealed with CEM exhibited significantly less microleakage in all determined periods of time [24, 72 and 168 hrs] than MTA groups [p< 0.001]

Conclusion: Based on the results of this study, CEM cement has a better sealing ability compared with MTA using fluid filtration method

Comparison of flare up incidence in patients treated by different practitioners

Statement of Problem: Flare up is an acute exacerbation of an asymptomatic pulpal and/or periapical pathosis after commencement or termination of root canal therapy. Its incidence may be different in patients treated by different practitioners regarding their graduation status

Purpose: The aim of this study was to compare flare up incidence in patients treated by dental students of Shiraz Dental School and those whom were treated by endodontists

Materials and Method: Patients' information including age, gender, and previous history of pain and pulp vitality were taken before treatment of 383 patients. 230 of them were treated by senior dental students of Shiraz Dental School and 153 of them were treated by endodontists. Students employed conventional step back technique whereas specialists had a chance to select variety of techniques. Data, regarding the quantity of pain experienced by patients were collected 48 hours after treatment. Case was considered a flare up if the patient had experienced severe pain which hadn't been reduced either by analgesic medication or by consequent swelling. Chisquare statistic tests were used to analyze the receiving data

Results: 41 individuals [10.7%] out of 383 patients depicted flare up. 13.5% of these patients were treated by students and 6.5% were treated by endodontists. The difference was statistically significant

Conclusion: Different rate of flare up in two groups is probably due to the dissimilarity in skills, techniques and materials used by different operators

[Evaluation of three different spreading forces using lateral condensation technique on apical leakage and tooth fracture: an in vitro study]

Lateral condensation technique is one of the most frequently used techniques for root canal obturation. There were few studies in order to determine the needed force for spreader penetration and its effect on apical seal. The purpose of this study was the in vitro evaluation of the effect of three spreader forces using the lateral condensation technique and the effect of these forces on root fractures. Eighty-five human mandibular premolar single rooted teeth without severe curvature and visible fractures were chosen and randomly divided into three groups. Each group of teeth were obturated on an acrylic model using three forces [1.6, 3 and 4.5 kg] with the lateral condensation technique. The teeth were observed under the stereomicroscope x6 again for any fracture line following clearing of the teeth and the maximum dye leakage penetration was measured for each tooth. The data were analyzed by using chi-square and Kruskal-Wallis statistical tests. All samples in the positive control group showed dye leakage but in the negative control group no sample showed any leakage. The mean dye penetration for the first [1.6 kg], second [3kg] and third [4.5 kg] groups was 0.344 mm, 0.153 mm and 0.746 mm, respectively. The 3kg force for lateral condensation technique produced a significantly better apical seal and less leakage in comparison with the other groups [P<0.05] and more fractures were observed with 4.5kg force [P<0.05]. The best force for lateral condensation in premolar teeth was 3kg and more pressure could produce more fracture

Comparison of the percentage of voids following root canal obturation with Gutta percha and ah26 sealer using four different sealer placement techniques

Different techniques are employed for sealer placementinto the root canal system. The purpose of this study was to compare the percentage of voids following root canal obturation with gutta percha and AH26 sealer using four different sealer placement techniques. In this laboratory experimental study, root canals of 50 mandibular second premolars were prepared using the step-back technique. The teeth were assigned to 4 experimental groups of 10 and one control group based on sealer placement technique. After sealer application and canal obturation with lateral condensation technique, specimens were horizontally cut into 3 mm slices. Sections were evaluated under a digital microscope at 150X magnification for void detection in apical, middle and coronal thirds. Kruskal Wallis and Bonferroni tests were applied to compare the percentage of voids between different groups. No significant difference was found in void percentage in one-thirds or total sections between the four methods [P=0.276]. Overall, no significant difference was noted in void percentage between the four techniques of sealer placement

[Effect of premedication with celecoxib and gelofen on reduction of post-endodontic pain]

Non-steroidal anti-inflammatory drugs [NSAIDs] are the most common drugs prescribed for controlling and post root canal treatment pain. During the last decade, a new generation of NSAIDs has been introduced such as Celecoxib and Gelofen with less gastrointestinal side effects and more analgesic effect. No studies have been performed to compare Celecoxib and Gelofen with other NSAIDs considering the reduction of post-endodontic pain; therefore, this study was designed. In this randomized double blind clinical trial study, 90 patients were divided into 3 groups and underwent root canal therapy. Celecoxib, Gelofen, or placebo was randomized prescribed to the patients 1 hour before treatment. The intensity of pain was recorded using visual analog scale [VAS] at 4, 8, 12, 24, 48 hours after completion of root canal treatment. The data were analyzed by means of repeated measurements, multiple comparisons and one way ANOVA tests using SPSS software. P<0.05 was considered as the level of significance. The results showed significant difference between Celecoxib and Gelofen in comparison with placebo at 8 and 12 hours after initiation of treatment. There was no significant difference among three groups at 4, 24, and 48 hours after initiation of treatment [P>0.05]. According to the results, use of Gelofen or Celecoxib before treatment reduces post-endodontic pain. These drugs can be prescribed before initiation of treatment as the effective agents for reduction of post-endodontic pain

[Comparison of three intra-canal irrigants effect on flare-up following treatment of necrotic teeth]

Acute pain and swelling following root canal therapy is considered as flare up. Pushing the infectious debris to the periapical region. Inadequate chemical and mechanical cleaning are the reasons for inflammation of this area. Microorganisms are the major causative agents of acute peri-radicular inflammation. Adequate and appropriate irrigation of the canal removes the intra-canal microorganisms, debris and infected agents from the canal space and may decrease pain and swelling. On the other hand, caustic effect of intra-canal irrigants may cause acute inflammation in the peri-radicular tissue. The aim of this study was to compare the effect of three intra-canal irrigants on the incidence of flare-up following root canal therapy of the teeth with necrotic pulp. In this clinical trial study, 225 patients with molar nectrotic pulp and peri-radiocular lesion were selected and randomly divided into three groups, 75 in each, Protaper Rotary files were used for preparing the canals and 2.5% sodium hypochlorite, 0.2% Chlorhexidine gluconate or saline were used for irrigation of the canals in each group respectively. Then, they were filled by lateral condensation technique. Questionnaires were given to the patients, asking for the level of their pain and swelling. The patients were followed for 48 hours. The data were statistically analyzed, using 'Chi-square, Mann-Whitney and Kruskal-Wallis tests. The results of this study showed no significant difference between irrigant solutions in the incidence of flare-up after endodontic treatment. Our clinical research indicated that the type of irrigating solution used makes little difference in the incidence of postoperative flare-up. It is difficult to attribute flare-up incidence specifically to the use for any particular irrigant

in vitro evaluation of human salvia penetration in obturated root canals with different pairs of root canal filling materials

Gutta-percha presents no adhesion to the tooth structure and sealers. Ideally, it should be replaced by a material that offers better sealing in the entire length of the root canal. The aim of this study was to compare the coronal microleakage of the root canal filled with different pairs of Gutta-percha [GP], Resilon, Epiphany and AH26. For this study, 130 mandibular premolars were chosen. After decoronation and preparation of the root canals of the teeth, they were divided into four experimental groups with 30 teeth each and 2 control groups. Group one was obturated with GP and AH26 sealer, group two with GP and Epiphany sealer, group three with Resilon tips and Epiphany sealer, and group four with Resilon tips and AH26 sealer. All the groups were obturated, using cold lateral condensation. Micro-leakage was tested using a two-chamber bacterial method. The data were subjected to statistical analysis, using a Kaplan-Meier test. The bacterial microleakage test showed no significant difference between groups [p=0.1718]. It is concluded that, in vitro, the epiphany obturation system is as good as gutta-percha sealed with AH26 when compared over 90 days of salvia storage

[Evaluation the risk factors of surgical site infection after elective colorectal operations]

Abstract Introductions: Surgical Site Infection [SSI] is the most commonly reported nosocomial infection among hospital surgical inpatients. Determining measurable perioperative factors for SSI may provide information on reducing complications and improving outcome

Objective: Assess the predictive risk factors of tissue and wound complications in open colorectal operation patients

Materials and Methods: We studied 186 consecutive patients who underwent elective colorectal operation [due to pathologies such as colon cancer, inflammatory bowel disease, familial adenomatous polyposis and so on] in a cohort study between February 2004 and September 2006 in a tertiary hospital. The main outcome of surgical site infection included incision or organ/space. Multivariate analysis was performed to assess the independent association of every factor with SSI. Also odds ratio [OR] with 95% confidence interval were reported

Results: The mean age of patients was 49.4 +/- 16.5 year, and 50.5% were females. The most common preoperative diagnoses included colorectal cancer [84.9%] and familial adenomatous polyposis [10.7%]. Eighteen [9.7%] of patients suffered SSI. Of measured variables, mechanical preparation with an OR=0.053 and p value=0.002, smoking [OR=29.422 and p value=0.011], type of wound [OR=12.87 and p value=0.01], operation time [OR=3.14 and p value=0.001] and colostomy [OR=12.42 and p value=0.019] independently predicted SSI

Conclusions: The incidence of SSI in patients who underwent elective colorectal operation in present study could conform to results of the previous studies literature. Perioperative mechanical preparation, smoking, type of wound, operation time and colostomy independently predicted

[Apical microleakage of obturated canals with apical plug and customized cone techniques in open apices models]

Management of open apices teeth is one of the most serious problems for dentists. Contemporary endodontics proceeds to single step techniques such as apical plug and customized cone for management of these cases. The purpose of this study was to compare apical microleakage between customized cone and apical plug techniques on open apices polyester made root canals. In this in vitro experimental study, 68 clear models were made from polyester in two different forms: S models [round canals], and L models [oval canals]. Thirty models [15 S and 15 L] were obturated with customized cone technique and 30 models [15 S and 15 L] were obturated with apical plug technique using Ca[OH]2 as an apical barrier. Eight models were considered as positive and negative control groups. Models were immersed in methylene blue for 48 hours and maximum linear dye penetration of each was measured by three separate observers. Student t test was used for statistical analysis of the findings. The results illustrated that the mean leakage of the customized cone group was statistically greater than apical plug group [p<0.05]. In addition, when comparing L and S models in customized group, L models showed more linear leakage than S models [p<0.05], but this difference was not significant in apical plug technique. The finding of this study indicated that the apical plug technique, when using Ca[OH]2 plug as a barrier may produce a better apical seal than the customized cone technique in short term

in-vitro evaluation of survival of entrococcus faecalis [E.F.] in infected root canals after root canal obturation with or without using of calcium hydroxide

The main goal of root canal therapy is total elimination of bacteria from root canals. Studies have shown that the cleaning and shaping of root canals can not complexly eliminate these bacteria from the root canals. Obturation may kill the bacteria due to entrapment of them into the canals and prevent their access to nutrition. On the other hand, using of Ca [OH][2] before obturation may help to promise a better reduction of bacteria from root canals. The purpose of this study is an in vitro evaluation of antibacterial effect of obturaiton solely, or with using Ca [OH][2] as an intracanal dressing on E.F. in infected human root canals. For this experimental study, 50 single rooted human teeth without significant curvature were chosen. After cutting the crowns and preparing root canals, the samples were sterilized and then contaminated with Entrococcus faecalis bacteria for 5 days. The samples were divided randomly into 4 groups. The first experimental group which included 20 teeth, were filled by Ca [OH][2] for one week before obturation by lateral condensation technique. The second experimental group [20 samples] were obturated by ZOE sealer and gutta percha with lateral condensation for 2 weeks. Five roots considered as positive control were contaminated with bacteria but were not obturated, and 5 other roots were obturated after sterilization without contamination as negative control group. All samples were incubated in 35°C and 10% moisture for 2 weeks. Then the coronal and apical part of roots were removed and the dentin powder were collected from the middle parts by drilling the canals in sterile condition. Two mg of dentin powder was weighed from each root and cultured in blood agar for 48 hours. The results were recorded and compared with each other by Chi-Square test. All samples were positive in culture of positive control group, and negative in culture of negative control group. First experimental group did not show any positive growth after the incubation period and there was only one positive culture in the second experimental group. The findings of this study illustrated no significant difference between the two experimental groups. In other words, the obturation of canals with gutta percha and sealer merely could kill the E.F. in the infected root canals and application of Ca [OH][2] before obturation was not necessary for disinfection of canals

[Antimicrobial effect of NaoCl, hydrated Ca[OH2], thyme oil and normal saline as irrigating solutions on black pigmented and strep viridance]

Introduction: Bacteria and their by-products are the main cause of pulpal and periapical diseases. Complete debridment and disinfection of the root canal is essential in order to sustain the long term successful results following root canal therapy. This study aims at comparing the antibacterial effect of NaoCl, Thyme oil, Hydrated Calcium Oxide and Normal Saline on selected bacteria isolated from infected root canals

Materials and Methods: Bacteria were collected from 25 infected root canals of patients who had not received antibiotics. The bacteria were collected in the tubes and transfered for bacteriologic examination. Streptococcous viridance and black Pigmented Bacteroid groups were detected by specific bacteriological examination. The experimental solutions were serially diluted 8-folds in saline. A certain volume of bacteria was added to each diluted solution. After 1, 5 and 15 minutes, the solution of each tube was poled onto 3% sheep blood agar plates and incubated at 37°c for 48 hours. The grown colonies were counted and the results were recorded

Results: The results of this study showed a significant antibacterial effect of thyme oil, hydrated calcium hydroxide and sodium hypocholorite on selected bacteria even in low concentration. Normal saline did not show any antibacterial effect

Conclusion: These findings recommended further studies on other aspects such as tissue toxicity, tissue solving and biocompatibility properties of these solutions to be applied for clinical use

[ in vitro comparison of anti bacterial effect of AH26 and AHplus sealers on infected root canals with enterococcus faecalis bacteria]

Statement of Problem: Bacteria and their destructive byproducts are the main causes of pulpal and periapical diseases. The main goal of the root canal therapy is to eliminate these bacteria from the root canal systems to prepare a suitable environment for the healing of periradicular tissues. Total elimination of these bacteria from root canal system is impossible, even by cleaning, shaping and irrigating with antibacterial solutions; therefore, utilization of antibacterial filling materials can help to achieve a better result

Aim: The purpose of this study was an in vitro comparison of antibacterial effect of AH26 and AHplus sealers on infected root canals with enterococcus faecalis bacteria

Materials and Methods: For this experimental study, 90 single rooted human teeth including upper incisors and canine were chosen. The crowns were removed and the root canals were cleaned and shaped. Smear layer was removed from canals and the roots were contaminated with entrococcuous faecalis bacteria following their sterilization. The roots were randomly divided into four experimental groups. The root canals of two groups were obturated using gutta percha and AH26 sealer with the lateral condensation technique. Root canals of the remaining groups were obturated by the same method but by using AHplus sealer. After incubation periods of 2 and 7 days, 4 mm segments were prepared from the middle third of roots and following removal of gutta percha from the segments, dentinal shavings were collected from the inside walls of the segments. The dentinal shavings were cultured and the presence of bacteria and the number of colonies were evaluated. The data were compared with each other by Mann-Withney and Chi-Square tests

Results: The findings of this study demonstrated that AH26 sealer can kill all the bacteria in 2 and 7 days but AHplus sealer can not eliminate the bacteria from the infected root canals and a significant rise in the number of colonies was seen when comparing the incubation period of 2 days with 7 days

Conclusion: The findings of this survey illustrated a strong antibacterial effect of AH26 in comparing with AHplus which may be due to the greater amount of formaldehyde releases from this sealer