Augmentation genioplasty using discarded bone fragments following proximal segment osteotomy of the ramus in intraoral vertical ramus osteotomy (IVRO).

BACKGROUND: Based on a three-dimensional (3D) orthognathic simulation, this technical report introduces a method for augmentation genioplasty using a proximal bone fragment of the mandible, which is typically discarded in intraoral vertical ramus osteotomy (IVRO). RESULTS: A 43-year-old female patient diagnosed with Class III malocclusion, presenting with a protruding mandible and long facial height, underwent surgical treatment. The surgical plan involved mandibular setback position using IVRO and augmentation genioplasty. The 3D orthognathic surgery including augmentation genioplasty simulation was performed. An excessively elongated proximal segment was sectioned following IVRO. The inferior part of the sectioned proximal bone fragment of the mandible was positioned to align with the requirements of advancement genioplasty. After ensuring that the placement of the fragment matched that of the simulated surgery, each bone fragment was fixed. At 1.5 years post-surgery, the grafted bone on the augmentation genioplasty was well maintained, with slight bone resorption. CONCLUSIONS: Augmentation genioplasty using the proximal bone fragment of the mandible, which is typically discarded in IVRO, reduces the surgical complications associated with chin osteotomy. When a secondary genioplasty is required, genioplasty with osteotomy, movement of the cut bone fragments, partial bone-shaving osteotomy, and additional bone grafting are viable options.

An evaluation of buccal infiltrations and inferior alveolar nerve blocks in pulpal anesthesia for mandibular first molars.

We compared the anesthetic efficacy of inferior alveolar nerve blocks (IANBs) with that of buccal infiltrations (BIs) in mandibular first molars. Using a crossover design, all subjects received a standard IANB or a BI of 1.7 mL of 4% articaine with 1:100,000 adrenaline (Septanest; Septodont, Saint-Maru-des-Fosses, France) on two appointments separated by at least 1 week. Pulpal anesthesia was determined by using an electric pulp tester. Electric pulp testing was repeated at 5, 8, 11, 15, 20, 25, and 30 minutes after the injections. Anesthesia was considered successful if the subject did not respond to the maximum output of the pulp tester at two or more consecutive time points. Fifty-four percent of the BI and 43% of the IANB were successful; the difference was not significant (p = 0.34). The onset of pulpal anesthesia was significantly faster with BI (p = 0.03). In conclusion, BI with 4% articaine for mandibular first molars can be a useful alternative for clinicians because compared with IANB it has a faster onset and a similar success rate.

A randomized controlled trial of various MTA materials for partial pulpotomy in permanent teeth.

OBJECTIVES: The aim of this study was to evaluate and compare the clinical applicability of various MTA materials as partial pulpotomy materials in permanent teeth. METHODS: Partial pulpotomy was performed on 104 permanent teeth from 82 people (mean 29.3±14.8years old), who met the inclusion criteria in randomized clinical trial. The teeth were divided into three groups: ProRoot MTA (n=33), OrthoMTA (n=36), RetroMTA (n=35). Clinical examination and radiographic comparison were carried out at 1, 3, 6 and 12 months after the treatment. Survival analysis was performed using the Kaplan-Meier survival curves and log rank tests. RESULTS: Partial pulpotomy sustained a high success rate up to 1year with no significant differences in the outcomes treated with three MTA materials: ProRoot MTA, 96.0%; OrthoMTA, 92.8%; RetroMTA, 96.0%. The Kaplan-Meier survival function curves showed no significant differences among three groups concerning clinical and radiographic cumulative survival rates. In addition, no potential prognostic factors related to the success rate of partial pulpotomy among age, sex, tooth type, root apex status, the site and type of pulp exposure, and the type of restoration were observed in log rank analysis. CONCLUSIONS: Partial pulpotomy with ProRoot MTA, OrthoMTA and RetroMTA had favorable results and clinical and radiographic results were not significantly different in three groups after 1year.

Effect of Topical Anesthesia on Pain from Needle Insertion and Injection and Its Relationship with Anxiety in Patients Awaiting Apical Surgery: A Randomized Double-blind Clinical Trial.

INTRODUCTION: We aimed to simultaneously investigate the effects of topical anesthesia on needle insertion and injection pain in the labial mucosa of the maxillary central incisors of patients awaiting apical surgery and to assess the relationship between patients' anxiety and pain scores. METHODS: Forty-four patients scheduled for apical surgery of the maxillary anterior incisor or canine were included, and all completed the Modified Dental Anxiety Scale (MDAS) questionnaire. One piece of Xylocaine (AstraZeneca, Sodertalje, Sweden) gauze was applied to the right or left side of the labial vestibule below the central incisor according to a randomization process, and 1 piece of water gauze was applied to the contralateral side of the labial vestibule. Each piece of gauze remained in place for 2 minutes. The subjects were asked to rate their pain according to the numeric rating scale immediately after needle insertion and anesthetic solution injection. RESULTS: Topical anesthetic application significantly reduced both insertion- and injection-related pain. Injection pain was significantly higher than insertion pain throughout the experiment. The difference in pain scores between the placebo and topical anesthetic groups was significantly greater for insertion pain than injection pain. The group with higher MDAS scores showed significantly higher pain scores, except for insertion pain reported by the topical anesthetic group, which did not show a significant difference between MDAS score groups. CONCLUSIONS: The topical anesthetic was highly effective for both insertion and injection pain during infiltration anesthesia in the maxillary central incisors. Highly anxious patients reported higher pain scores; however, topical anesthetics reduced the effect of anxiety on increasing pain.

Influence of Size and Volume of Periapical Lesions on the Outcome of Endodontic Microsurgery: 3-Dimensional Analysis Using Cone-beam Computed Tomography.

INTRODUCTION: The purpose of this study was to examine the size, volume, and other parameters of preoperative periapical lesions measured from cone-beam computed tomographic (CBCT) images as potential prognostic factors in endodontic microsurgery. METHODS: A clinical database was searched for patients who had received endodontic microsurgery with preoperative CBCT examination between March 2010 and December 2014. The CBCT images were analyzed with the OnDemand3D software program (Cybermed, Seoul, South Korea). The mesiodistal (Lx), apicocoronal (Ly), and buccolingual (Lz) diameter and the volume (V) of the periapical lesions, destruction of the cortical bone, and height of the buccal bone plate (Lb) were measured independently by 2 examiners. The outcome was classified as a success or failure based on the clinical and radiographic evaluation at least 1 year after the operation. Univariate analyses using the chi-square or Fisher exact test were performed to show the correlation of the outcomes with variables to identify the potential predisposing factors. Multivariate analysis using a logistic regression model was performed with the associated variables. RESULTS: Ninety-five cases were evaluated after a period of at least 1 year, and 2 were extracted before the 1-year follow-up. The interexaminer agreements were excellent for the linear and volume measurement of the preoperative periapical lesion. A lesion volume above 50 mm(3) was found to be a significant negative predictor in the univariate analysis (P = .028) and the logistic regression model (P = .038). CONCLUSIONS: Within the limitations of this study, the volume of the preoperative periapical lesion had a significant effect on the outcome of endodontic microsurgery. It is suggested that further studies on endodontic microsurgery should be performed and that quantitative measurements using CBCT imaging may be useful for the analyses.

Scanning electron microscopic examination of resected root apices obtained from endodontic microsurgery.

This study was designed to examine the morphological features of the resected root apices obtained from endodontic microsurgery using a scanning electron microscope (SEM) as well as their anatomical effect on the clinical outcome of the surgical treatment. One-hundred-six resected root apices from 91 patients/surgeries were obtained by endodontic microsurgery, and fixed immediately for storage. The resected apices were prepared for SEM to examine their morphological features, such as the number and size of the apical foramina. The patients were periodically checked up at least 1 year and the clinical outcome of the microsurgery was judged as a success or failure according to the Molven's criteria. The SEM findings and the clinical outcome of apical surgery were evaluated to see any potential correlation between them. The SEM examination revealed that 60.4% of specimens had more than two portals of exit on the resected root apices and the size of the major foramen was at least 386 micrometer and 334 micrometer from maxillary and mandibular molar, respectively. With a recall rate of 72.9%, 91.9% of the surgical cases were decided to have successful outcomes. Based on this SEM study, a relatively high frequency of multiple portals of exit was existed and the sizes of major foramina were bigger than that were reported in previous reports. The clinical outcomes of endodontic microsurgery were not correlated with the anatomical features of resected apical root apices. SCANNING 38:455-461, 2016. © 2016 Wiley Periodicals, Inc.

Polymerase chain reaction identification of microorganisms in previously root-filled teeth in a South Korean population.

A large body of evidence indicates that microorganisms are the primary causative agents of endodontic treatment failures. This study intended to assess the occurrence of nine putative endodontic pathogens in root-filled teeth associated with periradicular lesions in a South Korean population using a culture-independent molecular approach. Fourteen root-filled teeth with persistent periradicular diseases were selected for retreatment. After removal of the root canal filling, the canals were sampled, and a polymerase chain reaction assay using taxon-specific oligonucleotide primers was used for microbial detection. Bacteria were present in all cases, as revealed by amplification using ubiquitous 16S rDNA primers. The most frequently detected taxon was Enterococcus faecalis (64%), followed by Streptococcus spp. (21%) and Tannerella forsythensis (14%). The results of this study using a highly sensitive identification method are concurrent with those from other geographical locations using diverse identification methods in that E. faecalis is the main species found in cases of root-filled teeth associated with periradicular lesions.

Effect of different temperatures and penetration depths of a System B plugger in the filling of artificially created oval canals.

OBJECTIVES: The purpose of this study was to compare the gutta-percha-filled area in oval canals while varying the temperature and penetration depth of the System B plugger. STUDY DESIGN: Seventy-five resin blocks, with artificially created oval canals, were obturated by using a continuous wave technique. In groups 1, 2, and 3, the plugger was introduced to a depth of 4 mm from the apex at set temperatures of 100, 200, and 350 degrees C, respectively. In group 4, the plugger was inserted to a depth of 2 mm from the apex at a set temperature of 200 degrees C. Group 5 was obturated in the same way as group 2, and then an additional cold plugging was performed to a depth of 3 mm from the apex. The cross sections of the obturated canals were photographed, and the percentage of the gutta-percha-filled area (PGP) was measured. RESULTS: No significant differences were found between the 3 different temperature settings (P >.05). At 1 mm from the apex, group 4 showed the highest PGP (95.57% +/- 6.86), followed by group 5 (84.72% +/- 12.19), and group 2 (67.33 +/- 13.03) (P <.05). CONCLUSION: In artificially created oval canals, plugger temperature within the range used in this study did not affect the PGP. However, the penetration depth of the plugger was significantly related to PGP.

Effects of removing residual peroxide and other oxygen radicals on the shear bond strength and failure modes at resin-tooth interface after tooth bleaching.

PURPOSE: To investigate the effects of removing residual peroxide on the bond strength and the failure mode at the interface of resin-based composite and enamel after tooth bleaching. METHODS: Standard-sized light-cured resin cylinders were formed on, and bonded to the flattened bleached enamel surfaces of 60 human canine and premolars which had previously been subjected to three different surface treatments for 3 minutes: (1) catalase; (2) 70% ethanol; (3) sprayed water. For each experimental group (n=12), non-bleached teeth and 2-week post-bleached teeth without any surface treatment were used for negative and positive control respectively. Specimens were thermocycled, tested in shear until failure, and the results statistically analyzed. All fractured specimens were examined by scanning electron microscopy. RESULTS: Pretreatment of bleached surface with the catalase and the ethanol prior to bonding significantly improved the composite-enamel bond strength compared to the water-sprayed group (P< 0.05). However, the bond strength level of the ethanol group did not return to the level recorded for the non-bleached negative control group. Scanning electron microscopic examination of randomly selected, fractured specimens indicated that the peroxide-induced reduction in bond strength was related to alterations in both attachment-surface area at the resin-enamel interface and resin quality.

Periapical status related to the quality of coronal restorations and root fillings in a Korean population.

INTRODUCTION: The purpose of this study was to assess the prevalence of apical periodontitis in root canal-treated teeth from the Korean population and to evaluate the relationship between the quality of root canal fillings and coronal restorations and the periapical status of these teeth. METHODS: Full-mouth periapical radiographs at the Dental Hospital of Yonsei University, Seoul, South Korea, were examined. A total of 1030 endodontically treated teeth restored with full veneer crown-type restorations were evaluated by 2 independent examiners. Teeth were classified as healthy or diseased according to the periapical status. The quality of endodontic treatment and coronal restorations were also classified via radiographic and clinical evaluation. The data were analyzed using the chi-square test and logistic regression. RESULTS: Forty-one percent of all endodontically treated teeth were classified as diseased. Approximately 35.6% of the teeth had endodontic treatments that were rated as adequate. The diseased teeth rate for cases with adequate endodontic treatment was 24.5%, which was significantly lower when compared with teeth with inadequate endodontic treatment (49.9%). The number of teeth with adequate coronal restorations was 706 (68.5%). Teeth with adequate coronal restorations had a significantly decreased prevalence of diseased teeth (34.7%) compared with teeth with inadequate coronal restorations (54.3%). Teeth with both adequate root fillings and restorations showed a significantly better outcome (82.3%) than the others, and teeth with both inadequate root fillings and restorations showed a significantly worse outcome (41.2%) than the others. CONCLUSIONS: Data from this Korean population showed a relatively high prevalence of apical periodontitis. The quality of endodontic treatment and coronal restorations were of equal importance and were strong independent predictors of the periapical status.

In vivo quantitative evaluation of live and dead bacteria in root canal infection by using propidium monoazide with real-time PCR.

INTRODUCTION: For selective detection of viable bacteria with molecular methods, propidium monoazide (PMA) treatment has been successfully applied to a wide range of bacteria. The purpose of this study was to compare the quantity of live cells with the total amounts of both live and dead cells before and after chemomechanical preparation by using PMA in combination with real-time polymerase chain reaction (qPCR). METHODS: Twenty-one teeth with pulp necrosis and a periapical lesion were included. Bacterial sampling of the root canals was performed before (S1) and after (S2) chemomechanical root canal treatment. Each sample was separated into 2 different tubes. PMA was added to one of the tubes, and the other was left untreated. Then, DNA extraction and qPCR were performed. To evaluate the validity of the PMA treatment, the defined mixtures containing different ratios of live and dead cell suspensions of Enterococcus faecalis were either subjected to PMA treatment or not subjected to PMA treatment, followed by qPCR quantification. RESULTS: A paired t test showed a highly significant difference in the mean threshold cycle values between S1 with and without PMA (P = .0002), and this difference (0.89) was similar to that (0.96) obtained from the samples consisting of 80% live cell suspension and 20% dead cell suspension of E. faecalis. The threshold cycle values between the S2 samples with and without PMA were also significantly different (P = .0134), and this difference (0.37) was similar to that obtained from the 100% live cell suspension of E. faecalis (0.42). CONCLUSIONS: PMA in conjunction with qPCR appeared to be useful in analyzing the primary infections of root canals because there were significant amounts of dead bacteria in the root canals. Although the use of PMA treatment in post-preparation samples significantly reduced the detection of dead bacteria, this difference was still small, so further studies should be carried out to confirm the necessity of PMA treatment.

Invasive cervical resorption: treatment challenges.

Invasive cervical resorption is a relatively uncommon form of external root resorption. It is characterized by invasion of cervical region of the root by fibrovascular tissue derived from the periodontal ligament. This case presents an invasive cervical resorption occurring in maxillary lateral incisor, following damage in cervical cementum from avulsion and intracoronal bleaching procedure. Flap reflection, debridement and restoration with glass ionomer cement were performed in an attempt to repair the defect. But after 2 mon, more resorption extended apically. Considering root stability and recurrence potential, we decided to extract the tooth. Invasive cervical resorption in advanced stages may present great challenges for clinicians. Therefore, prevention and early detection must be stressed when dealing with patients presenting history of potential predisposing factors.

Hypoesthesia after IAN block anesthesia with lidocaine: management of mild to moderate nerve injury.

Hypoesthesia after an inferior alveolar nerve (IAN) block does not commonly occur, but some cases are reported. The causes of hypoesthesia include a needle injury or toxicity of local anesthetic agents, and the incidence itself can cause stress to both dentists and patients. This case presents a hypoesthesia on mental nerve area followed by IAN block anesthesia with 2% lidocaine. Prescription of steroids for a week was performed and periodic follow up was done. After 1 wk, the symptoms got much better and after 4 mon, hypoesthesia completely disappeared. During this healing period, only early steroid medication was prescribed. In most cases, hypoesthesia is resolved within 6 mon, but being aware of etiology and the treatment options of hypoesthesia is important. Because the hypoesthesia caused by IAN block anesthesia is a mild to moderate nerve injury, early detection of symptom and prescription of steroids could be helpful for improvement of the hypoesthesia.

Continued development of the root separated from the main root.

INTRODUCTION: Endodontic infection or physical trauma of a developing tooth might lead to unusual situation for root development. METHODS: Two cases are presented. Both cases involved immature mandibular second premolars with infected pulps. In the first case, the tooth was treated by apexification, whereas revascularization procedures were performed in the second case. Interestingly, a separated root tip was observed with the main root at the initial presentation of case 2. RESULTS: At recall after apexification, a separate root tip was observed apically to the main root end, and root development continued in case 1. In the second case, the separate root displayed continuing root formation, but the main root did not gain root thickness or length. CONCLUSIONS: These cases revealed that Hertwig's epithelial root sheath and stem cells from the apical papilla can be separated from the main tooth structure by an external force or iatrogenic factors and thereafter produce a separate root tip.

Prognostic factors for clinical outcomes in endodontic microsurgery: a retrospective study.

INTRODUCTION: This retrospective study examined the potential prognostic factors on the outcome after endodontic microsurgery and compared the predictors of isolated endodontic lesion with those of both isolated endodontic lesions and endodontic-periodontal lesions. METHODS: The data were collected from patients with a history of endodontic microsurgery performed between August 2004 and December 2008 and at least 1 year before being evaluated. Surgical procedures were performed by the endodontic faculty and residents. After surgery, an operation record form was made with the preoperative, intraoperative, and postoperative factors from the clinical and radiographic measures. For statistical analysis of the predisposing factors, the dependent variable was the dichotomous outcome (ie, success vs failure). RESULTS: Of 907 cases, 491 were retained at follow-up. At the 0.05 level of significance, age, sex (female), tooth position (anterior), root-filling length (inadequate), [corrected] lesion type (endodontic lesion), root-end filling material (mineral trioxide aggregate and Super EBA; Harry J. Bosworth, Skokie, IL), and restoration at follow-up appeared to have a positive effect on the outcome. On the other hand, with an isolated endodontic lesion, the tooth position (anterior), root-filling length (inadequate), [corrected] and restoration at follow-up were significant factors at the 95% confidence level. CONCLUSIONS: Under the control of the significant variables in logistic regression, the potential prognostic factors on the outcome were sex, tooth position, lesion type, and root-end filling material. On the other hand, the tooth position was a pure predictor of an endodontic lesion affecting the clinical outcome.

Comparison of the cleaning efficacy of a new apical negative pressure irrigating system with conventional irrigation needles in the root canals.

OBJECTIVES: This study evaluated the efficacy of EndoVac system in comparison with that of a conventional needle irrigation method when the root canals were enlarged to various sizes. STUDY DESIGN: Sixty-nine single-rooted teeth were divided into 3 groups according to the root canal irrigation system (24G and 30G needle and EndoVac). Each group was divided into 3 subgroups according to the MAF size (#25, #40, and #60). Four-micron-thick serial sections were prepared at 1.5 and 3.5 mm from the apical level and photographs were taken for the analysis. The influence of the irrigation system and apical size was evaluated using a 1-way ANOVA test and Tukey's test (P < .05). RESULTS: At both levels, significant differences were detected between EndoVac system and conventional needle irrigation in removing debris (P < .05). The relationship between the MAF size and irrigation efficacy was found to have a positive relationship (P < .05). CONCLUSIONS: EndoVac left significantly less debris behind than the conventional needle irrigation methods. Although all 3 irrigation methods resulted in clean root canals because the percentage occupied by remaining debris was very low in our specimens, larger apical instrumentation seemed to improve apical root canal debridement.

An in vivo comparison of working length determination by only root-ZX apex locator versus combining root-ZX apex locator with radiographs using a new impression technique.

OBJECTIVE: The objective of this study was to compare, in vivo, the accuracy of working length determination using only the Root-ZX electronic apex locator versus adjusting Root-ZX measurements after obtaining a working length radiograph. STUDY DESIGN: The working length was determined in 25 premolar root canals using Root-ZX and K-files were fixed at these positions. Radiographs were acquired and interpreted, and the recorded working length measurement was adjusted, if necessary, for a combined measurement. The teeth were then extracted in an effort to determine the position of the file tip to the root canal constriction. On the basis of the position of the file tip to the apical foramen, polyvinylsiloxane impressions of the root apex were taken, or the root was imbedded in acrylic resin and ground in order to measure the position of the file tip to the apical constriction. RESULTS: The Root-ZX alone detected the apical constriction within +/- 0.5 mm in 84% of the samples (21 of 25 canals). However, 96% (24 of 25 canals) were within this range when the combination of Root-ZX and radiographs was used. We noted no statistical significance between these 2 methods (P > .05). CONCLUSION: Using a Root ZX Electronic Apex Locator combined with radiographs is recommended for the determination of working length, although there was no statistical significance between those 2 groups in this study.

Differences in prevalence of selected bacterial species in primary endodontic infections from two distinct geographic locations.

OBJECTIVE: This study intended to compare the prevalence of 7 putative endodontic pathogens in samples of primary endodontic infections taken from patients of 2 distant geographic locations. STUDY DESIGN: Samples from infected root canals associated with asymptomatic periradicular lesions or from pus aspirated from acute periradicular abscesses were collected from patients in Rio de Janeiro, Brazil, and Seoul, South Korea. South Korean samples were frozen and delivered to Brazil, where all steps in the molecular analysis were performed. DNA was extracted and a species-specific nested polymerase chain reaction assay was used to detect 7 target bacterial species. RESULTS: The most prevalent species detected in Brazilian samples were Porphyromonas endodontalis (79% of the cases) , Treponema denticola (79%), and Dialister pneumosintes (76%). The most prevalent species found in South Korean samples were Fusobacterium nucleatum (38% of the cases) , Tannerella forsythia (26%), and Treponema maltophilum (24%). Overall, P endodontalis, D pneumosintes, Filifactor alocis, T denticola, and T forsythia were significantly more detected in Brazilian samples than in South Korean samples ( P < .05). CONCLUSIONS: Findings indicated that the prevalence of some species in infections of endodontic origin may significantly differ from one geographic location to another.