Resorption Cavities Research Articles

A case of bone resorption in the mentum caused by hyaluronic acid filler in a patient with skeletal Class II jaw deformity.

Chin augmentation by hyaluronic acid filler injection rarely causes abnormal bone resorption in the mentum. Thus, when taking the history of a patient with jaw deformity, it is imperative to check the history of treatment of the mentum. Hyaluronic acid (HA) filler injection is a common procedure in nonsurgical cosmetic chin augmentation. Due to its high biocompatibility and simple injection technique, HA filler injection is a popular procedure. However, adverse events such as allergic reactions and foreign body reactions have been reported in some cases. In this study, we report a case of skeletal Class II jaw deformity in which bone resorption was observed in the mentum after HA filler injection. The purpose of this study is to discuss the indications for HA filler injection in skeletal Class II cases that require orthognathic surgery. The patient was a 30-year-old woman. To improve retrusion of the mentum, she has been receiving HA filler injections in the mentum three times every 6 months in the cosmetic surgery clinic since 2015. However, the retrusion of the mentum did not improve, which prompted here to visit the orthodontic clinic. Radiographs and CT revealed bowl-shaped bone resorption surrounding the foreign bodies in the mentum. She was diagnosed with maxillary protrusion, vertical maxillary excess, mandibular retrusion, and bilateral condylar resorption. Bimaxillary orthognathic surgery (BOGS) and removal of residual HA fillers were planned after completion of the preoperative orthodontic treatment. After BOGS, the foreign bodies were completely removed, and the resorption cavities were filled with excess bone segments from the surgical sites. X-ray photoelectron spectroscopy analysis of the foreign bodies suggested the presence of HA. One year after the BOGS, no progression of condylar resorption occurred, and bone healing at the mentum had a good prognosis. Therefore, the patient underwent reduction and advancement genioplasty. She was satisfied with her facial profile and occlusal function. Unexpected bone resorption in the mentum caused by HA filler injection is often discovered incidentally. Although, patients may feel hesitant to confess their history of treatment of the mentum, it is important to ensure that they are carefully interviewed.

Can ultrasonography be used to detect root perforation? An invitro study.

This study assessed the usability of ultrasonography in detecting root canal perforations. The buccal side of incisor root were perforated. The actual lengths up to the perforation site were measured by visualisation of the tip of a file. Specimens were embedded in gypsum, and it was scraped to simulate bone resorption. Resorption cavities were filled with ultrasound gel. Measurements were taken by advancing a file through the canal until the tip became visible in the ultrasound image. 3D scans were obtained using cone-beam computed tomography (CBCT) and the distance between the coronal point of the resorption cavity and the reference point was measured. The actual distance of the resorption cavity from the reference point varied 6-10.6 mm. The same distances were measured via ultrasound as 5.7-10.9 mm, while measured using CBCT 6-10.5 mm. No significant differences were found. Ultrasonography shows promise for detecting root perforations, however further research is needed.

Irrigation techniques for calcium hydroxide removal from resorption cavities

Irrigation techniques for calcium hydroxide removal from resorption cavities

Stress Distribution of External Resorption Cavities with Different Materials

Stress Distribution of External Resorption Cavities with Different Materials

Medicaments removal with different techniques from internal resorption cavities

Medicaments removal with different techniques from internal resorption cavities

Evaluation of different irrigation activation techniques for the removal of various medicaments from a simulated internal resorption cavity: an in vitro study.

This study aimed to assess the efficacy of different activation techniques in removing calcium hydroxide (Ultracal XS), Ledermix, and Bio-C Temp from simulated internal root resorption (IRR) cavities. 108 single-rooted maxillary incisors were prepared using Reciproc R50 files. Simulated IRR cavities, 2mm in diameter and located 8mm from the apex, were created. Ultracal XS, Ledermix, and Bio-C Temp were applied to the samples, grouped by irrigation activation techniques: Standard Needle Irrigation (SNI), EDDY, Passive Ultrasonic Irrigation (PUI), and XP-endo Finisher (XPF). Medicament removal efficacy was evaluated using a standardized scoring system. Statistical analysis was performed using the Kruskal-Wallis test. XPF and PUI were more effective than SNI in medicament removal across the groups, with no significant difference. EDDY showed no significant difference than other groups. Ledermix was more effectively removed in all activation groups compared to Bio-C Temp. The XPF was superior in removing Ultracal XS compared to Bio-C Temp. However, none of the groups achieved complete medicament removal. XPF and PUI techniques enhance medicament removal efficacy. Bio-C Temp was more difficult to remove from the IRR cavities than other medicaments. Bio-C Temp could be removed from the canals less effectively compared to calcium hydroxide and Ledermix. Among the tested irrigation activation methods, XPF and PUI were found to be more effective at removing the tested medicaments.

Evaluation of the efficacy of different irrigation activation techniques in removing of calcium hydroxide on teeth with the simulated internal root resorption cavity: a confocal laser scanning microscope analysis.

The aim of this study is to evaluate the effect of different irrigation activation methods on root canal sealer penetration in teeth with simulated internal root resorption (IRR) and calcium hydroxide (CH) applied using a confocal laser scanning microscope (CLSM). 60 incisors with a single root and a single canal were included in the study. IRR cavities were created in the middle third of the root canal, and CH was placed. The samples were randomly divided into 4 groups (n = 15) according to the irrigation activation method to be tested: standard needle irrigation (SNI), sonic activation (EDDY), photon-induced photoacoustic flow (PIPS), and shock wave enhanced emission photoacoustic flow (SWEEPS). After irrigation activation applications, the root canals were obturated. Sections of 1.0 ± 0.1mm were taken from the apical, middle, and coronal regions of each sample. The penetration area (µm2) and maximum penetration depth (µm) of the root canal sealer were examined by CLSM and analyzed using ImageJ software. Statistical analysis was performed with a one-way ANOVA and post-hoc Tukey test at the P < 0.05 significance level. Among all irrigation activation methods tested, both the penetration area and maximum penetration depth of the root canal sealer were greater in the coronal region than in the apical region (p < 0.05). In the IRR region, there was no difference in terms of maximum penetration depth between PIPS and SWEEPS (p > 0.05), it was highest in SWEEPS (p < 0.05). PIPS and SWEEPS were better than other irrigation activation methods in the penetration of root canal sealer in the resorption areas of teeth with IRR.

The ability of three different protocols in removing Bioceramic- and Resin-Based sealers from simulated internal resorption cavities: an in vitro study

The ability of three different protocols in removing Bioceramic- and Resin-Based sealers from simulated internal resorption cavities: an in vitro study

Comparative Effectiveness of Different Er:YAG Laser-Activated Irrigation Systems on Removing Calcium Hydroxide from Simulated Internal Root Resorption Cavities at Different Root Levels.

Objective: To investigate the effectiveness of Er:YAG laser-activated irrigation (LAI) with a short pulse duration for removing calcium hydroxide (CH) from simulated internal root resorption (IRR) cavities at three root levels. Background: Pulse duration is an important parameter during LAI, which ensures the efficiency of irradiation and the corresponding activation process. Short pulses in the range of a few microseconds enable rapid expansion and successive implosion of irrigants, resulting in distinct fluid movement. There have been few reports on CH removal efficacy from IRR cavities of different LAI systems, including those using short pulse duration. Methods: IRR cavities (1.6 mm diameter) were created at the apical, middle, and coronal root levels in 60 mandibular premolars and filled with a radiopaque CH paste. Samples were assigned to the following irrigation groups (n = 12, each): (1) LAI(P)-F, a prototype laser device that operates with short pulse duration (Morita Manufacturing) with a flat tip; (2) LAI(EA)-F, the ErwinAdverl laser device (Morita Manufacturing) with a flat tip; (3) LAI(EA)-T, the ErwinAdverl laser device with a tapered tip; (4) PIPS-T, the Lightwalker laser device (Fotona) with a tapered tip; and (5) SI, the syringe irrigation group. The laser tips were fixed at the canal entrance. The remaining CH volume and surface area were assessed in IRR cavities using micro-computed tomography and scanning electron microscopy, respectively. Data were statistically analyzed utilizing one-way analysis of variance and Tukey's test at 5% significance level. Results: The LAI(P)-F and PIPS-T groups exhibited the highest CH removal rates at three different levels (p < 0.05). The LAI(EA)-F group had a significantly better efficacy of CH removal compared with the LAI(EA)-T group at the middle level (p < 0.05). Conclusion: The LAI(P)-F and PIPS-T groups demonstrated superior efficiency in removing CH from simulated IRR cavities.

Characterization and quantification of in-vitro equine bone resorption in 3D using μCT and deep learning-aided feature segmentation

High cyclic strains induce formation of microcracks in bone, triggering targeted bone remodeling, which entails osteoclastic resorption. Racehorse bone is an ideal model for studying the effects of high-intensity loading, as it is subject to focal formation of microcracks and subsequent bone resorption. The volume of resorption in vitro is considered a direct indicator of osteoclast activity but indirect 2D measurements are used more often. Our objective was to develop an accurate, high-throughput method to quantify equine osteoclast resorption volume in μCT 3D images. Here, equine osteoclasts were cultured on equine bone slices and imaged with μCT pre- and postculture. Individual resorption events were then isolated and analyzed in 3D. Modal volume, maximum depth, and aspect ratio of resorption events were calculated. A convolutional neural network (CNN U-Net-like) was subsequently trained to identify resorption events on post-culture μCT images alone, without the need for pre-culture imaging, using archival bone slices with known resorption areas and paired CTX-I biomarker levels in culture media. 3D resorption volume measurements strongly correlated with both the CTX-I levels (p < 0.001) and area measurements (p < 0.001). Our 3D analysis shows that the shapes of resorption events form a continuous spectrum, rather than previously reported pit and trench categories. With more extensive resorption, shapes of increasing complexity appear, although simpler resorption cavity morphologies (small, rounded) remain most common, in acord with the left-hand limit paradigm. Finally, we show that 2D measurements of in vitro osteoclastic resorption are a robust and reliable proxy.

An Evaluation of the Fracture Resistance of Teeth with Simulated External Cervical Resorption Cavities Categorized Using Three-Dimensional Classification.

(1) Background: External cervical resorption causes dental hard tissue destruction that may reduce the fracture resistance of affected teeth. By using a compressive strength test, this study aimed to evaluate the fracture resistance of teeth with simulated external cervical resorption cavities that have different three-dimensional classifications. (2) Methods: In total, 170 teeth with simulated external cervical resorptions were divided into 16 experimental groups (n = 10) and 1 control group (n = 10) based on the three-dimensional classification: 1Ap, 1Bp, 1Cp, 1Dp, 2Ap, 2Bp, 2Cp, 2Dp, 3Ap, 3Bp, 3Cp, 3Dp, 4Ap, 4Bp, 4Cp, 4Dp and a control group. Defects were restored with mineral trioxide aggregate. The fracture resistances of the samples were statistically analyzed using two-way repeated ANOVA and the Bonferroni correction for multiple comparisons at a significance level of p < 0.05. (3) Results: The lowest resistance to fracture was observed in samples with vertical height level "4" and circumferential spread of "D" (p < 0.001). In the groups with circumferential spreads "B", "C" and "D", there were significant differences between the samples with vertical height levels "1", "2", "3" and "4" regarding fracture resistance (p < 0.001). (4) Conclusions: The circumferential spread and vertical height of the external cervical resorption influenced the fracture resistance of the affected teeth.

Three-Dimensional Measurement of Obturation Quality of Bioceramic Materials in Filling Artificial Internal Root Resorption Cavities Using Different Obturation Techniques: An In Vitro Comparative Study

IntroductionPathologic conditions such as internal root resorption (IRR) may complicate root canal filling. This study aimed to evaluate and compare the obturation quality by measuring the percentage of obturation volume (POV) in root canals with artificial IRR obturated with different materials and techniques using cone beam computed tomography (CBCT). MethodsForty single canal extracted mandibular premolars were decoronated to standardize their length to 14 mm. Following instrumentation, the roots were cut horizontally, and artificial IRR cavities were made at the level of 7 mm from the apex. The root halves were joined using cyanoacrylate adhesive. The samples were randomly assigned to 4 groups (n = 10), and the canals were filled as follows: single-cone technique (SC), bulk-fill Bio-C Sealer (BF), and Bio-C Repair for the coronal and middle third (BCR) + cold lateral condensation technique (CLC) for the apical third and continuous wave compaction technique (CWC). The pre- and postobturation volumes and the POV were measured in the total canal and for the apical, middle, and coronal thirds separately using CBCT and Mimics Medical software. The results were analyzed statistically using one-way ANOVA and Tukey HSD test, and statistical significance was set at P < .05. ResultsBF group resulted in significantly lower total, coronal, middle and apical POV values compared to SC, BCR + CLC, and CWC groups (P < .05), respectively. Also, at the apical third, the BCR + CLC group showed significantly lower POV than the SC and CWC groups (P < .05), respectively. The intra-group comparison showed that BF and BCR + CLC groups had a significantly lower POV in the apical third compared to the middle third (P < .05). Conversely, the CWC group had a significantly higher apical POV than the middle third (P < .05). ConclusionsThe maximum POV was obtained using the CWC technique, Bio-C Repair, and SC technique with Bio-C Sealer, making their application in IRR more preferable than the BF Bio-C Sealer.

Toll-like receptor-2 induced inflammation causes local bone formation and activates canonical Wnt signaling.

It is well established that inflammatory processes in the vicinity of bone often induce osteoclast formation and bone resorption. Effects of inflammatory processes on bone formation are less studied. Therefore, we investigated the effect of locally induced inflammation on bone formation. Toll-like receptor (TLR) 2 agonists LPS from Porphyromonas gingivalis and PAM2 were injected once subcutaneously above mouse calvarial bones. After five days, both agonists induced bone formation mainly at endocranial surfaces. The injection resulted in progressively increased calvarial thickness during 21 days. Excessive new bone formation was mainly observed separated from bone resorption cavities. Anti-RANKL did not affect the increase of bone formation. Inflammation caused increased bone formation rate due to increased mineralizing surfaces as assessed by dynamic histomorphometry. In areas close to new bone formation, an abundance of proliferating cells was observed as well as cells robustly stained for Runx2 and alkaline phosphatase. PAM2 increased the mRNA expression of Lrp5, Lrp6 and Wnt7b, and decreased the expression of Sost and Dkk1. In situ hybridization demonstrated decreased Sost mRNA expression in osteocytes present in old bone. An abundance of cells expressed Wnt7b in Runx2-positive osteoblasts and ß-catenin in areas with new bone formation. These data demonstrate that inflammation, not only induces osteoclastogenesis, but also locally activates canonical WNT signaling and stimulates new bone formation independent on bone resorption.

Reinforcement of Teeth Having Reenacted Perforating Internal Resorption Cavities After Repair Using Different Calcium Silicate-based Cements and Backfilling Materials: An In vitro Study

ABSTRACT To evaluate the fracture resistance (FR) of the teeth having reenacted perforating internal resorption cavities repaired by distinctive calcium silicate-based cements (CSCs) specifically: Endocem MTA, Biodentine, NeoMTA Plus, and backfilling materials. Ninety-six freshly extracted human mandibular premolar teeth were selected. Twelve roots were used as the negative control group. Rotary files were used to complete the final irrigation and root canal preparation on the remaining teeth. Following that, burs were used to make standardized internal resorption chambers in the middle part of the roots. Twelve of these samples were used as positive control samples. The remaining 72 root canals were obturated in the apical 4 mm using a single-cone approach, and they were separated into 6 groups based on the CSCs used to fill voids and the materials used as backfilling. Group 1: Endocem MTA (resorption) + Endocem MTA (coronal), Group 2: Endocem MTA (resorption) + Gutta-percha/sealer (coronal), Group 3: Biodentine (resorption) + Biodentine (coronal), Group 4: Biodentine (resorption) + Gutta-percha/sealer (coronal), Group 5: NeoMTA Plus (resorption) + NeoMTA Plus (coronal), and Group 6: NeoMTA Plus (resorption) + Gutta-percha/sealer (coronal). Specimens were inserted in acrylic resin and then subjected to fracture testing. Fracture strength tests were performed using a Universal Testing Machine. The force was employed vertically with a consistent speed of 1 mm/minute. The results were analyzed with Variance and Bonferrini tests at P &lt; 0.005. The mean force of fracture values were 447.00, 201.25, 318.75, 187.50, 596.58, 258.75, 347.50, and 298.75 N for Group 1, 2, 3, 4, 5, 6, 7, and 8, respectively. “There was a significant difference (P &lt; 0.001) between the experimental groups and the control group”. Group 5 showed the highest FR as compared to other groups. Backfilling with CSCs appears to be a better material than a gutta-percha/sealer combination. Neo MTA plus furthermore appeared the highest fracture-resistant material, while Biodentine + Gutta percha/sealer showed the least FR.

Effects of melatonin against experimentally induced apical periodontitis in rats.

Apical periodontitis is an inflammatory condition resulting from microbial invasion in the root canal system, causing periapical tissue destruction and bone resorption. This study investigated melatonin's effects, known for its antioxidant and anti-inflammatory properties, on experimentally induced apical periodontitis in rats. Three groups of rats were studied: control, apical periodontitis and apical periodontitis with melatonin treatment. Proinflammatory cytokines and enzyme levels in blood serum were measured, and micro-CT analysis assessed bone resorption. Results showed significantly elevated cytokines and enzyme levels in the apical periodontitis group compared to the control. However, in the melatonin-treated group, these levels were significantly reduced (p < 0.01-0.001). Micro-CT analysis indicated decreased periapical resorption cavity volume and surface area with melatonin treatment. This suggests that systemic melatonin administration can mitigate inflammation and reduce bone resorption in experimentally induced apical periodontitis in rats, potentially holding promise for human endodontic disease treatment pending further research.

Evaluation of rise in pH and oxygen release at the site of simulated external root resorption cavities using different oxygen-releasing biomaterials: An in vitro study.

External inflammatory root resorption has rapid onset and progresses aggressively. It leads to cementum loss, which allows communication between the infected pulp and the periodontium through the denuded dentinal tubules. Primary management strategy includes adequate chemomechanical debridement and lesion arrest for which maintaining alkaline pH and aerobic conditions is essential for healing and repair of the resorption defect. The aim of this study is to evaluate rise in pH and oxygen release at the site of simulated external root resorption cavities using different oxygen-releasing biomaterials. In 40 extracted single-rooted teeth access opening and chemomechanical debridement were done. Cavities simulating resorption defect are prepared on the roots. The samples are divided into four groups (n = 10) based on the biomaterial used. After placing the biomaterial, the root apices were sealed. Half of the samples from each group were tested for oxygen release using dissolved oxygen meter and the other half for rise in pH using pH meter at 7, 14, 21, and 28 days. The pH values were analyzed using Friedman 2-way analysis of variance (ANOVA) and Kruskal-Wallis test. Oxygen release was measured using the two-way and repeated-measures ANOVA. Calcium peroxide group showed the highest mean pH and oxygen release than other groups at any given point of time. Incorporating oxygen-releasing biomaterials such as calcium peroxide and perfluorodecalin into intracanal medicaments, such as calcium hydroxide, creates an alkaline and oxygen-enriched milieu in the periapical tissues.

Evaluation of Filling Quality of Obturation Techniques in Internal Resorption Cavities Created with a Novel Methodology

Evaluation of Filling Quality of Obturation Techniques in Internal Resorption Cavities Created with a Novel Methodology

Trichloroacetic Acid - Historical Origins and Dental Applications.

The use of trichloroacetic acid in dentistry has been advocated by several authors in the last 50 years due to its action on invasive gingival tissues that are seen in the presence of cervical resorption or proximal cavities. Publications addressing this substance and its applications are completely silent regarding its historical evolution or make general claims regarding its original source without substantiation. This perspective will attempt to provide the missing links to this substance and its contemporary use in dentistry, specifically in Endodontics.

Effects of N-acetyl-L-cysteine against apical periodontitis in rats with adriamycin-induced cardiomyopathy and nephropathy.

This study aimed to investigate the potential protective effects of N-acetyl-L-cysteine (NAC) against apical periodontitis (AP) in rats with adriamycin (ADR)-induced kidney and heart diseases. Fourty-eight Wistar albino rats were divided into six groups: (1) Control group, (2) ADR group (1 mg/kg/day ip for 10 days), (3) AP Group (1st mandibular molar tooth), (4) AP + ADR Group, (5) AP + NAC group (150 mg/kg/day ip), and (6) AP + ADR + NAC group. After 3 weeks, the rats were decapitated and blood and tissue samples (heart, kidney, and jaw) were collected. Tissue samples were evaluated by biochemical (inflammatory cytokines and hemodynamic parameters) and radiological analyses. One-way anova with Tukey post hoc tests was used to compare data, considering p < .05 as statistically significant. The serum levels of TNF-α, IL-1β, BUN, Creatinine, CK, and LDH were elevated in the test groups compared with the control group, and treatment with NAC reduced these levels (p < .05). Heart and kidney tissue analysis showed a higher heart-to-body weight ratio (HW/BW) and kidney-to-body weight ratio (KW/BW) in the test groups compared with the control group (p < .05). No significant differences in HW/BW and KW/BW were found between the control and AP + NAC groups. Volumetric apical bone resorption analysis showed an increase in periapical radiolucencies in AP-induced groups indicating apical periodontitis. NAC treatment reduced the total area and volume of resorption cavities (p < .05). The results suggest that NAC's antioxidant and anti-inflammatory effects can reduce adriamycin-mediated heart and kidney damage and may have a positive effect on apical periodontitis in individuals with nephropathy and cardiomyopathy.

Pulp tissue dissolution capacities of different irrigation agitation techniques in artificial internal resorption cavities.

The aim of this in vitro study was to compare the organic tissue dissolution capacities of 3 different irrigation agitation techniques (IATs) in artificial internal root resorption cavities (IRCs). Ninety freshly extracted maxillary human incisors were selected. After decoronation procedure, the roots were split longitudinally, and a standard IRC were prepared in the canals on each half of the roots. Then, the bovine pulp samples (~2,3 mg) were previously weighed and placed into the cavities. The root fragments were reassembled and cemented to create a circular IRC within the canal. Teeth samples were randomly divided into 6 groups (n=15); sodium chlorur (NaCl) and sonic irrigation (SI), sodium hypochlorite (NaOCl) and SI, NaCl and passive ultrasonic irrigation (PUI), NaOCl and PUI, NaCl and laser activated irrigation (LAI), NaOCl and LAI. After that, the teeth were decemented and the tissue samples inside the cavities were weighed again. The percentage of weight loss was calculated and statistically analyzed. SI has significantly more successful results than PUI and LAI in groups which the irrigant was NaCl. There was also a significant difference between LAI and PUI in groups which the irrigant was NaOCl (Group 6 ˃ Group 4, p=0.003). There was no significant difference between LAI and SI with NaOCl. Complete dissolution of bovine pulp tissue from IRCs was not achieved by any tested techniques. However, the LAI with NaOCl was more effective than other IATs. In addition, there is no significant difference between the LAI and SI with NaOCl.