Healing and Spontaneous Realignment of Displaced Roots With Periapical Granuloma After Microsurgical Endodontic Treatment (Three Years' Follow-up): A Case Report.

Endodontic therapy aims to treat or prevent apical periodontitis, a condition characterized by inflammation of the periapical tissues at the apex of the tooth root. This case study demonstrates the successful nonsurgical and surgical management of a large periapical lesion involving the lower central incisors with root displacement induced by a periapical granuloma. A patient was referred from the maxillofacial department for endodontic treatment due to persistent pain and swelling in the lower anterior region started two months ago. Upon arrival, a clinical examination and radiographic assessment were performed using cone-beam computed tomography (CBCT). The CBCT scan revealed a significant radiolucent area measuring (10x8) mm extending from the lower left lateral incisor to the right central incisor. The lower left central incisor was necrotic and tender to palpation and percussion. A nonsurgical root canal was performed followed by an apicectomy using mineral trioxide aggregate (MTA) to facilitate healing of the periapical lesion. Histopathological examination of the lesion confirmed the diagnosis of periapical granuloma. At follow-up 1, 2, and 3 years' visits, the periodontal assessment was performed and found to be free of pain upon percussion or palpation. No other clinical or radiological signs or symptoms were identified except for a small radiolucent area mesially adjacent to the root of the lower left central incisor. The development of materials such as MTA has significantly improved the prognosis of cases with large periapical lesions. In this case, healing and spontaneous realignment of the root were observed after three years.

Evaluation of root and canal morphology of mandibular premolar amongst Saudi subpopulation using the new system of classification: a CBCT study.

BACKGROUND: The clinician should have complete knowledge of the normal anatomy of the root as well as complexities in the root canal configuration for a better outcome, as missed or improper handling of the canal system can lead to the failure of an entire endodontic procedure. The present study aims to assess the morphology of roots and canals in permanent mandibular premolars in the Saudi subpopulation with a new classification system. METHODS: The present study includes 1230 mandibular premolars (645 first premolars and 585-second premolars) from 500 CBCT images of the patients, including retrospective data. iCAT scanner system (Imaging Sciences International, Hatfield, PA, USA) was used to obtain the images; scanning of 8 × 8 cm images was performed at 120 KVp and 5-7 mA with a voxel size of 0.2 mm. The new method of classification presented by Ahmed et al. 2017 was used to record and classify the root canal morphology, followed by recording the differences regarding the age and gender of the patients. Comparison of canal morphology in lower permanent premolars and its association with gender and age of the patients was done by Chi-square test/ Fisher exact test; the significance level was set at 5% (p ≤ 0.05). RESULTS: The left mandibular 1st and 2nd premolars with one root were 47.31%, with two roots were 2.19%. However, three roots (0.24%) and C-shaped canals (0.24%) were reported only in the left mandibular 2nd premolar. The right mandibular 1st and 2nd premolars with one root were 47.56%, with two roots were 2.03%. The overall percentage of the number of roots and canals in the first and second premolars 1 PM 1 (88.38%), 2 PM 1 B 1 L 1 (3.5%), 2 PM B 1 L 1 (0.65%), 1 PM 1-2-1 (3.08%), 1 PM 1-2 (3.17%), 1 PM 1-2-1-2 (0.24%), 3 PMMB 1 DB 1 L1 (0.48%). However, the C-shaped canals (0.40%) were reported in right and left mandibular second premolars. No statistically significant difference was reported between mandibular premolars and gender. A statistically significant difference was reported between mandibular premolars and the age of the study subjects. CONCLUSION: Type I (1 TN 1) was the major root canal configuration in permanent mandibular premolars, which was higher among males. The CBCT imaging provides thorough details about the root canal morphology of lower premolars. These findings could support diagnosis, decision-making, and root canal treatment, for dental professionals.

External Cervical Resorption: A Case Report and Brief Review of the Literature, and Treatment Algorithms.

AIM: This report presents a case of external cervical resorption and illustrates the effects of a non-surgical approach in the amelioration of this condition and discusses the etiology, classifications, and treatment options. BACKGROUND: One of the most common root resorption forms is external cervical resorption, which initiates in the cervical area of the tooth and spreads out in the thickness of the dentin in an irregular way. This resorptive process may spread across the dentin leading to significant loss of tooth structure, with or without pulp involvement. CASE DESCRIPTION: During a routine radiographic examination of a 25-year-old female patient, external cervical resorption in a maxillary right second premolar was discovered. Cone-beam computed tomography (CBCT) confirmed the extension of the lesion into the pulp and the need for root canal treatment. The defect was sealed with bioceramic putty. One year CBCT follow-up demonstrated the cessation of the resorption site with no clinical symptoms. CONCLUSION: CBCT examination and combining non-surgical root canal treatment with non-surgical repair using bioceramic putty was an effective treatment option. CLINICAL SIGNIFICANCE: Treatment selection of external cervical resorption depends on many factors, including the location and severity of the resorptive defect and the remaining tooth structure. If the resorptive defect has extended to the pulp, the management involves root canal treatment and subsequent placement of a direct restoration to restore the resorptive lesion.

Assessment of Mesiobuccal Canal Configuration, Prevalence and Inter-Orifice Distance at Different Root Thirds of Maxillary First Molars: A CBCT Study.

AIM: The aims of this study were to assess the prevalence and configuration of the second mesiobuccal (MB2) canal in the mesiobuccal MB root of permanent maxillary first molars at different root levels in a Saudi sub-population using cone­beam computed tomography (CBCT) and to measure the inter-orifice distance between MB & MB2 at the pulpal floor level. MATERIALS AND METHODS: This retrospective study was carried out on CBCT images of Saudi patients seen at King Abdul Aziz University. A total of 106 maxillary first molars were evaluated using a specialized software program (iCAT CBCT software). The prevalence of MB2, canal configuration and location of joining (apical-middle-coronal), if present was calculated. Also, the inter-orifice distance between both canals was measured at the level of the pulpal floor. Chi­square and one-way analysis of variance (ANOVA) were used. RESULTS: The MB2 canal was found in 92 (86.8%) maxillary first molar teeth. The MB and MB2 canals were joined in 61 (58%) cases, where the location of joining was 14 (23%), 17 (27%), and 31 (50%) in the coronal, middle, and apical third, respectively. The mean inter-orifice distance between both canals at the level of the pulpal floor was 2.52±0.76 mm. CONCLUSION: The prevalence of MB2 canal in this Saudi sub-population was high. The prevalence decreased as the root canal approached the apical third. There was no correlation between the average distance and occurrence of canal joining. CBCT is useful in detecting and mapping the mesiobuccal root canal system, with a likelihood of enhancing the quality of root canal treatment.

Reciproc Endodontic File Surface Defects After Single Use: An SEM Analysis.

OBJECTIVE: The aim of this investigation was to detect defects that may occur to Reciproc endodontic files after a single use. MATERIALS AND METHODS: A sample of convenience of Reciproc files (VDW GmbH, Munich, Germany) that were used to prepare root canals of anterior or posterior teeth were collected. The files were divided equally into two groups: Group 1 (R25) files were used to prepare mesial root canals of 50 human permanent mandibular molars, and Group 2 (R40) included 50 files that were used to prepare permanent maxillary incisor teeth. Files were analyzed after single use by using a scanning electron microscope at X120 to detect changes in surface morphology. The data were statistically analyzed by using the χ2 test, and statistical significance was set at P < 0.05. RESULTS: A total of 96 Reciproc NiTi files were collected; of those, 67 (70%) were unaffected and 29 (30%) showed overall surface deformations. The types of deformation were blade disruption (22%), surface pitting (12%), and unwinding and tip deformation (1%). No microcracks were detected, and none of the studied files showed fracture. R40 was three times more likely to be deformed and showed blade disruption compared with R25 (P < 0.05). CONCLUSIONS: Reciproc rotary NiTi files show high resistance to deformation after a single use. Blade disruption was the most frequent defect occurring in both the small and large files.

Pulp volume changes after piezocision-assisted tooth movement: a randomized clinical trial.

BACKGROUND: Orthodontic treatment may result in undesirable side effects, such as root resorption and a decrease in the size of the pulp tissue which could be associated with the duration of the orthodontic treatment. Piezocision-assisted tooth movement was introduced as a minimally invasive surgical procedure to shorten orthodontic treatment time. This prospective randomized clinical trial was aimed to compare the pulp volume changes of maxillary anterior teeth after en-masse retraction with or without piezocision-assisted orthodontics. METHODS: Patients who required orthodontic treatment with bilateral maxillary first premolar extractions and en-masse retraction were recruited. Patients were randomly divided into extraction with piezocision, or only extraction, serving as controls. Pulp volume and root length changes of the maxillary six anterior teeth were measured and compared between the two groups using a 3-Dimensional analytical software. Paired and independent sample t-tests were used to compare within and between groups. Bivariate correlation was done between the mean change in pulp volume and its corresponding root length. The significance level was set at α = 0.05. RESULTS: A total of 23 patients were included, 12 in the piezocision, and 11 in the control group. At the end of the en-masse retraction phase, (mean = 122.74 ± 3.06 days) pulp volume was significantly decreased in all six anterior teeth in both groups (P < 0.01). The decrease in pulp volume was not statistically different between both groups, (P > 0.05). There was a statistically significant but moderate correlation only between the pulp volume change of the right canine and its root length, r = 0.44, P = 0.034. CONCLUSIONS: The effect of piezocision-assisted orthodontic tooth movement on the pulp volume was comparable to the conventional orthodontic treatment. The degree of change in pulp volume does not appear to be related to the amount of root resorption. Trial registration NCT03180151. Registered December 25, 2016, retrospectively registered, https://clinicaltrials.gov/ct2/show/record/NCT03180151 .

Prevalence of periodontitis in high school children in Saudi Arabia: a national study.

BACKGROUND: The occurrence of periodontitis is rather infrequent in children and adolescence and increases with age. We conducted this study because there have been few epidemiological studies on prevalence of periodontitis in children in Saudi Arabia. OBJECTIVE: Determine the prevalence of periodontitis in high school children in Saudi Arabia. DESIGN: Cross-sectional, using cluster and multistage sampling. SETTING: High school children in Saudi Arabia. PARTICIPANTS AND METHODS: Periodontal examinations were conducted on a randomized sample of high school children between the ages 15 to 19 in Saudi Arabia. The study spanned from September 2012 to January 2016. Clinical examinations included measurements of the probing depth (PD) percentage of PD ≥4 mm per patient. MAIN OUTCOME MEASURES: The prevalence of periodontitis (PD ≥4 mm and CAL ≥1 mm), the mean percentage PD ≥4 mm, the mean percentage CAL ≥1 mm, plaque index (PI) and gingival index (GI). SAMPLE SIZE: 2435 high school students. RESULTS: Of 2435 high school children in the sample, 209 students (8.6%) had periodontitis. The mean (standard deviation) for the PD was 0.59 (0.17) mm. Differences in percentage PD ≥4 mm and CAL ≥1 mm were greater in students with periodontitis ( P<.001). The prevalence of periodontitis was higher among non-Saudis, students who did not brush their teeth and did not visit their dentist regularly. In the bivariate analysis, periodontitis was positively associated with GI, PI, number of teeth extracted, mean percentage PD ≥4 mm, and mean PD. However, in the multivariate analysis, tooth brushing was the main factor protective against periodontitis (odds ratio: 0.62, 95% CI 0.42-0.92, P=.017). CONCLUSION: Periodontitis prevalence was high compared with Western countries in a nationally representative sample of high school students in Saudi Arabia. LIMITATIONS: Partial mouth study design, which may underestimate the disease prevalence. CONFLICT OF INTEREST: None.

Elevated Expression of Macrophage Migration Inhibitory Factor Promotes Inflammatory Bone Resorption Induced in a Mouse Model of Periradicular Periodontitis.

Locally produced osteoclastogenic factor RANKL plays a critical role in the development of bone resorption in periradicular periodontitis. However, because RANKL is also required for healthy bone remodeling, it is plausible that a costimulatory molecule that upregulates RANKL production in inflammatory periradicular periodontitis may be involved in the pathogenic bone loss processes. We hypothesized that macrophage migration inhibitory factor (MIF) would play a role in upregulating the RANKL-mediated osteoclastogenesis in the periradicular lesion. In response to pulp exposure, the bone loss and level of MIF mRNA increased in the periradicular periodontitis, which peaked at 14 d, in conjunction with the upregulated expressions of mRNAs for RANKL, proinflammatory cytokines (TNF-α, IL-6, and IL-1ß), chemokines (MCP-1 and SDF-1), and MIF's cognate receptors CXCR4 and CD74. Furthermore, expressions of those mRNAs were found significantly higher in wild-type mice compared with that of MIF-/- mice. In contrast, bacterial LPS elicited the production of MIF from ligament fibroblasts in vitro, which, in turn, enhanced their productions of RANKL and TNF-α. rMIF significantly upregulated the number of TRAP+ osteoclasts in vitro. Finally, periapical bone loss induced in wild-type mice were significantly diminished in MIF-/- mice. Altogether, the current study demonstrated that MIF appeared to function as a key costimulatory molecule to upregulate RANKL-mediated osteoclastogenesis, leading to the pathogenically augmented bone resorption in periradicular lesions. These data also suggest that the approach to neutralize MIF activity may lead to the development of a therapeutic regimen for the prevention of pathogenic bone loss in periradicular periodontitis.

Assessment of the involvement of the macrophage migration inhibitory factor-glucocorticoid regulatory dyad in the expression of matrix metalloproteinase-2 during periodontitis.

Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine and counter-regulator of endogenous glucocorticoids (GCs). It is implicated in acute and chronic inflammatory diseases. This study investigated the role of the MIF-GC regulatory dyad in the expression and release of matrix metalloproteinase-2 (MMP-2) during periodontitis, in vivo and in vitro. In a Mif-knockout (KO) mouse model of ligature-induced periodontitis, gingival tissues and blood were collected and analysed for levels of interleukin-6 (IL-6), MIF, MMP-2, and corticosterone. In addition, human gingival fibroblasts (HGFs) were tested for production of IL-6 and MMP-2 after stimulation with hydrocortisone (HC), MIF, tumour necrosis factor-alpha (TNF-α), or Fusobacterium nucleatum, a pathogen known to elicit immune responses during periodontitis. Wild-type (WT) mice showed a local and systemic increase of MIF levels during inflammation, which was confirmed by increased local IL-6 concentrations. Systemic GC levels were reduced in WT and Mif-KO mice during inflammation, with overall lower concentrations in Mif-KO mice. In vivo and in vitro, MMP-2 production was not dependent on MIF or inflammatory stimuli, but was inhibited by HC. Therefore, MIF does not appear to stimulate expression of MMP-2 in the gingival tissues, whereas GC upregulates MIF and downregulates MMP-2. Our findings further suggest that MIF may regulate systemic GC levels.

Phosphoglycerol dihydroceramide, a distinctive ceramide produced by Porphyromonas gingivalis, promotes RANKL-induced osteoclastogenesis by acting on non-muscle myosin II-A (Myh9), an osteoclast cell fusion regulatory factor.

Among several virulence factors produced by the periodontal pathogen Porphyromonas gingivalis (Pg), a recently identified novel class of dihydroceramide lipids that contains a long acyl-chain has the potential to play a pathogenic role in periodontitis because of its higher level of tissue penetration compared to other lipid classes produced by Pg. However, the possible impact of Pg ceramides on osteoclastogenesis is largely unknown. In the present study, we report that the phosphoglycerol dihydroceramide (PGDHC) isolated from Pg enhanced osteoclastogenesis in vitro and in vivo. Using RAW264.7 cells, in vitro assays indicated that PGDHC can promote RANKL-induced osteoclastogenesis by generating remarkably larger TRAP+ multinuclear osteoclasts compared to Pg LPS in a TLR2/4-independent manner. According to fluorescent confocal microscopy, co-localization of non-muscle myosin II-A (Myh9) and PGDHC was observed in the cytoplasm of osteoclasts, indicating the membrane-permeability of PGDHC. Loss- and gain-of-function assays using RNAi-based Myh9 gene silencing, as well as overexpression of the Myh9 gene, in RAW264.7 cells showed that interaction of PGDHC with Myh9 enhances RANKL-induced osteoclastogenesis. It was also demonstrated that PGDHC can upregulate the expression of dendritic cell-specific transmembrane protein (DC-STAMP), an important osteoclast fusogen, through signaling that involves Rac1, suggesting that interaction of PGDHC with Myh9 can elicit the cell signal that promotes osteoclast cell fusion. Taken together, our data indicated that PGDHC is a Pg-derived, cell-permeable ceramide that possesses a unique property of promoting osteoclastogenesis via interaction with Myh9 which, in turn, activates a Rac1/DC-STAMP pathway for upregulation of osteoclast cell fusion.

TRAP-positive osteoclast precursors mediate ROS/NO-dependent bactericidal activity via TLR4.

Osteoclastogenesis was induced by RANKL stimulation in mouse monocytes to examine the possible bactericidal function of osteoclast precursors (OCp) and mature osteoclasts (OCm) relative to their production of NO and ROS. Tartrate-resistant acid phosphatase (TRAP)-positive OCp, but few or no OCm, phagocytized and killed Escherichia coli in association with the production of reactive oxygen species (ROS) and nitric oxide (NO). Phagocytosis of E. coli and production of ROS and NO were significantly lower in TRAP+ OCp derived from Toll-like receptor (TLR)-4 KO mice than that derived from wild-type (WT) or TLR2-KO mice. Interestingly, after phagocytosis, TRAP+ OCp derived from wild-type and TLR2-KO mice did not differentiate into OCm, even with continuous exposure to RANKL. In contrast, E. coli-phagocytized TRAP+ OCp from TLR4-KO mice could differentiate into OCm. Importantly, neither NO nor ROS produced by TRAP+ OCp appeared to be engaged in phagocytosis-induced suppression of osteoclastogenesis. These results suggested that TLR4 signaling not only induces ROS and NO production to kill phagocytized bacteria, but also interrupts OCm differentiation. Thus, it can be concluded that TRAP+ OCp, but not OCm, can mediate bactericidal activity via phagocytosis accompanied by the production of ROS and NO via TLR4-associated reprograming toward phagocytic cell type.

Macrophage Migration Inhibitory Factor (MIF) Supports Homing of Osteoclast Precursors to Peripheral Osteolytic Lesions.

By binding to its chemokine receptor CXCR4 on osteoclast precursor cells (OCPs), it is well known that stromal cell-derived factor-1 (SDF-1) promotes the chemotactic recruitment of circulating OCPs to the homeostatic bone remodeling site. However, the engagement of circulating OCPs in pathogenic bone resorption remains to be elucidated. The present study investigated a possible chemoattractant role of macrophage migration inhibitory factor (MIF), another ligand for C-X-C chemokine receptor type 4 (CXCR4), in the recruitment of circulating OCPs to the bone lytic lesion. To accomplish this, we used Csf1r-eGFP-knock-in (KI) mice to establish an animal model of polymethylmethacrylate (PMMA) particle-induced calvarial osteolysis. In the circulating Csf1r-eGFP+ cells of healthy Csf1r-eGFP-KI mice, Csf1r+/CD11b+ cells showed a greater degree of RANKL-induced osteoclastogenesis compared to a subset of Csf1r+/RANK+ cells in vitro. Therefore, Csf1r-eGFP+/CD11b+ cells were targeted as functionally relevant OCPs in the present study. Although expression of the two cognate receptors for MIF, CXCR2 and CXCR4, was elevated on Csf1r+/CD11b+ cells, transmigration of OCPs toward recombinant MIF in vitro was facilitated by ligation with CXCR4, but not CXCR2. Meanwhile, the level of PMMA-induced bone resorption in calvaria was markedly greater in wild-type (WT) mice compared to that detected in MIF-knockout (KO) mice. Interestingly, in contrast to the elevated MIF, diminished SDF-1 was detected in a particle-induced bone lytic lesion of WT mice in conjunction with an increased number of infiltrating CXCR4+ OCPs. However, such diminished SDF-1 was not found in the PMMA-injected calvaria of MIF-KO mice. Furthermore, stimulation of osteoblasts with MIF in vitro suppressed their production of SDF-1, suggesting that MIF can downmodulate SDF-1 production in bone tissue. Systemically administered anti-MIF neutralizing monoclonal antibody (mAb) inhibited the homing of CXCR4+ OCPs, as well as bone resorption, in the PMMA-injected calvaria, while increasing locally produced SDF-1. Collectively, these data suggest that locally produced MIF in the inflammatory bone lytic site is engaged in the chemoattraction of circulating CXCR4+ OCPs. © 2016 American Society for Bone and Mineral Research.

The antimicrobial activity of the appetite peptide hormone ghrelin.

The present study examined the antimicrobial activity of the peptide ghrelin. Both major forms of ghrelin, acylated ghrelin (AG) and desacylated ghrelin (DAG), demonstrated the same degree of bactericidal activity against Gram-negative Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa), while bactericidal effects against Gram-positive Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis) were minimal or absent, respectively. To elucidate the bactericidal mechanism of AG and DAG against bacteria, we monitored the effect of the cationic peptides on the zeta potential of E. coli. Our results show that AG and DAG similarly quenched the negative surface charge of E. coli, suggesting that ghrelin-mediated bactericidal effects are influenced by charge-dependent binding and not by acyl modification. Like most cationic antimicrobial peptides (CAMPs), we also found that the antibacterial activity of AG was attenuated in physiological NaCl concentration (150mM). Nonetheless, these findings indicate that both AG and DAG can act as CAMPs against Gram-negative bacteria.