Periodontal Ligament Width Research Articles

Clinical, radiographic and biochemical assessment of proximal cavities restored with composite resin using incremental vs. bulk packing techniques: One-year randomized clinical trial

BackgroundBulk-fill resin composites may suffer from recurrent caries around compound proximal restorations in posterior teeth, especially at the proximo-gingival interface.Over 12 months, will the bulk fill technique affect the caries recurrence rate at gingival margins when compared to the conventional incremental packing technique? How early will the first clinical, radiographical, and biochemical evidence of caries recurrence occur?MethodsAfter randomization, in 30 patients with two compound (OM or OD) supragingival lesions, one tooth was restored using the bulk fill technique on one side (group 1) (n = 15). In contrast, the other tooth on the other side was restored utilizing the incremental layering technique (group 2) (n = 15). Both teeth received restorative material (X-tra fil, Voco, Cuxhaven, Germany). The FDI criteria were used to evaluate restorations. As for the periodontal assessment, the gingival index, plaque index, papillary bleeding scoring index and periodontal pocket depth were evaluated. The gingival crevicular fluid (GCF) specimens were gathered, and MMP-9 was extracted and quantitated by ELISA. A customized radiographic template was designed, and 3D printed digital bitewing radiographs were taken. Assessments were done clinically, radiographically and biochemically at baseline (1 week) and after 3, 6 and 12 months. Data was statistically analyzed.ResultsThe null hypothesis was accepted clinically; no statistically significant differences appeared between bulk and incrementally filled posterior restorations. As for the radiographic assessment, the null hypothesis was accepted except for increased periodontal ligament width at 3 months. The null hypothesis for the biochemical evaluation was rejected as there were significant changes in levels of MMP-9 at different testing times.Conclusions1. With similar results but less sensitivity and significant time saving, the bulk fill technique can be considered an efficient alternative to the incremental fill technique in restoring proximal cavities. 2. Early evidence of caries recurrence can be correlated to an increase in the MMP-9 level in gingival crevicular fluid, followed by an increase in radiographic periodontal ligament width measurement.Trial registrationAn ethical approval from the Research Ethics Committee at the Faculty of Dentistry, October 6 University, (Approval No. RECO6U/5-2022). The study was registered at the Pan African Clinical Trials Registry on 24/07/2023 with an identification number (PACTR202307573531455).

Endodontic radiography - what’s displaying the radiograph? The yield of commercial computer screens vs. DICOM calibrated medical screens in endodontic radiography

ObjectiveA comparison between commercial computer screens and DICOM-calibrated medical screens for characterizing anatomy and diagnosing dental pathologies was performed. The aim of this study was to evaluate and compare the ability of each of those screens to identify root apices and widening of the periodontal ligament (PDL) in the posterior maxillary area.Materials and MethodsDigital X-ray images of 53 maxillary molar teeth were examined by means of a commercial computer screen and again two months later with a DICOM screen to compare their ability to help identify and diagnose PDL widening and to locate the root apices of those teeth.ResultsThe DICOM screen had a significantly better ability to identify widened PDLs (from 31.4% to 34.8% of the cases compared to 19% to 26.1% for the commercial screens, P < .001), depending upon the observer. The DICOM screen was also significantly superior in depicting the root apices compared to the commercial screens (from 77.4% to 83.6% of the cases compared to 56% to 66.7% for the commercial screens, P < 0.001), depending upon the observer.ConclusionDICOM-calibrated medical screens were significantly superior to commercial computer screens for identifying widened PDLs and locating the root apex in the posterior maxillary area.

Effects of Chitosan as a Novel Obturation Material for Pulpectomized Teeth on Periapical Inflammation, Periodontal Ligament Widening, and Hard Tissue Resorption: A Preliminary Exploratory Study on Dogs.

Objectives: This preliminary animal study was conducted to assess the effects of chitosan as a novel obturation material for pulpectomized teeth on periapical inflammation, periodontal ligament (PDL) widening, and hard tissue resorption. Materials and Methods: Forty premolar root canals in two mature dogs were obturated with zinc oxide eugenol (ZOE) and an experimental 3% chitosan paste (n=20 in each group). The teeth were then restored with amalgam. After 28 days, the dogs were sacrificed, and histopathological assessment was performed. The amount of resorbed obturation material, degree of inflammatory response, degree of PDL widening, and the number of bone/cementum/dentin resorption defects were recorded under ×40 and ×200 magnifications. Data were analyzed using the Mann-Whitney U test, one-sample Wilcoxon signed-rank test, and Fisher's exact test (α=0.05). Results: Bone, cementum, and dentin resorption were seen in 6, 10, and 1 chitosan-obturated canals and 14, 15, and 0 ZOE-obturated canals, respectively. Only the bone resorption defects were significantly fewer in the chitosan group (P=0.026). Mild, moderate, and severe inflammation were observed in 17, 3, and 0 chitosan-obturated canals, and 7, 9, and 4 ZOE-filled canals, respectively (P=0.004). Mild, moderate, and severe PDL widening were seen around 15, 5, and 0 chitosan-filled canals and 7, 12, and 1 ZOE-filled canals, respectively (P=0.025). Conclusion: The 3% chitosan was superior to ZOE in terms of causing less inflammation and PDL widening. It also decreased bone resorption and acted similar to ZOE in terms of dentin and cementum resorption.

Impact of Local Melatonin Application on Expression Level of Osteogenic Marker (Runx2) and Post-orthodontic Relapse in Ovine Model: A Split Mouth Study

Background: Retaining teeth in their proper alignment after orthodontic treatment can be highly challenging. This study aimed to estimate the effectiveness of locally injected melatonin in improving bone remodelling and reducing post-orthodontic relapse. Methods: The third incisors on the right and left quadrants of six sheep were removed and the second and fourth incisors were brought close together by using a sectional orthodontic appliance. Melatonin solution was injected near and parallel to the mesial surface of the second incisor and the distal surface of the fourth incisor on one quadrant while the other quadrant received 1% dimethyl sulphoxide as a control. Four weeks later, the orthodontic appliance was debonded and the teeth were allowed to move back. By utilizing digital analysis, the relapse distance of the approximated incisors was measured at 21 and 42 days respectively after appliance removal. Histological and mRNA expression analysis of osteogenic marker (Runx2) were conducted to evaluate the periodontal space width and the surrounding alveolar bone of the melatonin-treated and control side incisors. Result: clinical and histological measurements showed that the approximated incisors in the melatonin-treated quadrant had a significantly shorter relapse distance (p≤0.05), significantly smaller periodontal ligament width (p≤0.05) and significantly larger new bone area formation (p≤0.05) than in the control quadrant. The mRNA expression level of the osteogenic marker (Runx2) was significantly larger (p≤0.05) in the melatonin-treated quadrant than in the control quadrant. The outcomes of this research suggest that melatonin can enhance bone remodelling and reduce post-orthodontic relapse in sheep.

Physiological occlusal force attenuates replacement root resorption of replanted teeth: an experimental animal study

BackgroundTooth avulsion represents the most severe form of dental trauma, necessitating tooth replantation as the primary treatment. However, the risk of replacement root resorption (RRR) poses a significant threat to tooth retention following replantation. This study preliminarily aimed to investigate the effect of physiological occlusal force on RRR after the replantation of avulsed teeth and to explore the potential underlying mechanisms.MethodsThirty-six 4-week-old male Sprague-Dawley rats underwent extraction and immediate replantation of their left maxillary molars. The rats were randomly divided into two major groups: the occluded (n = 18) group, where the opposite mandibular teeth were preserved; non-occluded (n = 18) group, where the opposite mandibular teeth were extracted. Within each major group, there were three subgroups corresponding to 7 days, 14 days, and 2 months, resulting in a total of six subgroups, (n = 6 per subgroup). The right maxillary first molars served as the normal control. Various periodontal characteristics were assessed using haematoxylin-eosin (H&E), tartrate-resistant acid phosphatase (TRAP) staining, and micro-computed tomography (micro-CT).ResultsHistological staining revealed that under occlusal force, the early stage (day 7) after tooth replantation mainly manifested as root surface resorption, especially in the non-occluded group, which gradually diminished over time. Cementum and periodontal ligament (PDL) repair was observed on day 14. Micro-CT analysis indicated a significant decrease in PDL width in the non-occluded group two months after replantation, consistent with the histological findings, signifying severe RRR in the non-occluded group.ConclusionsThis study provides preliminary evidence that physiological occlusal force may attenuate osteoclastogenesis during the early stage of tooth replantation, thereby reducing the occurrence of RRR and promoting periodontal healing.

Enhancing orthodontic treatment control with fish scale-derived hydroxyapatite nanoparticles: Insights from an animal model study

ObjectivesThis study investigates the impact of injected fish-scale-derived hydroxyapatite nanoparticles (FsHA-NPs) on orthodontic tooth movement (OTM) and the width of the periodontal ligament (PDL) space. Materials and MethodsTwenty-six Wistar rats underwent mesial orthodontic traction with a force of 50 g for 21 days. Following the application of the orthodontic appliance, the rats were randomly divided into two groups: a control group, which received a 0.3 µg saline injection, and the experimental FsHA group, which received 100 mg/0.3 ml of FsHA-NPs after thorough characterisation. Injections were administered immediately after appliance application and repeated at 7 and 14 days. Statistical analysis was conducted with a significance level of P ≤ 0.05. ResultThe experimental group exhibited a significant reduction in OTM at 7-, 14-, and 21-day post-force application. Additionally, a reduction in PDL width was observed in the mesiocervical and disto-apical regions of the mesial and distal roots of the first molar. ConclusionFsHA-NPs derived from biowaste fish scales exhibit promising potential as biomaterials for enhancing control over OTM. This study underscores the viability, accessibility, and safety of FsHA-NPs as a locally injectable material for orthodontic applications.

Clinical and Radiographic Evaluation of Mineral Trioxide Aggregate and Human Amniotic Membrane Pulpotomy in Primary Molars: A Randomized Clinical Trial.

To clinically and radiographically compare the outcomes of pulpotomy with mineral trioxide aggregate (MTA) and human amniotic membrane (HAM) in primary molar teeth at 1, 3, 6, and 12 months. The study was a randomized clinical trial with two arms. One arm consisted of participants whose pulpotomy was conducted using MTA, called group I, and the other arm, using HAM, was designated group II. Both MTA and HAM exhibited 100% clinical success. Also, there were no signs of external resorption, periapical bone destruction, or internal resorption in both the MTA and the HAM groups at all four time intervals in this study. However, periodontal ligament widening was seen in 30% of the participants in the MTA group at 1-month and at the 12-month follow-up, whereas in the HAM group, periodontal ligament widening was found to reduce significantly from 22.2% at 1-month to 11.1% at the 12-month follow-up. The HAM exhibited favorable clinical and radiographic outcomes in the present study. Mineral trioxide aggregate is the most preferred choice as a pulpotomy agent for deciduous teeth. However, various drawbacks associated with MTA have been fueling the need for newer, effective agents. HAM is not only easily available, cost-effective, and easy to handle but also favors tissue regeneration. The positive outcome of the present study strongly advocates the use of HAM as an alternative to MTA for pulpotomy in primary teeth. Joseph EJ, Rao A, Mahabala KY, et al. Clinical and Radiographic Evaluation of Mineral Trioxide Aggregate and Human Amniotic Membrane Pulpotomy in Primary Molars: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2024;17(6):641-646.

Endodontic retreatment of a mesotaurodontic mandibular first molar with C-shaped configuration in a patient with multiple taurodonts: A case report and review of literature

Abstract Taurodontism is a dental anomaly characterized by an apical displacement of the pulp chamber floor, resulting in a large pulp chamber with short roots. It can be associated with certain syndromes and abnormalities, although it is common to occur as an isolated characteristic. This anomaly can occur along with other root canal system anomalies such as C-type configuration. The aim of this report is to present the successful endodontic management of a C-shaped mesotaurodontic mandibular molar and review the literature available on this matter. A 23-year-old Persian female was referred by her dental surgeon to complete the root canal treatment of her right mandibular first molar (#46). Clinical examination showed a temporized cavity with no response to pulpoperiapical tests or visible pocket depth while an elongated root trunk with slight periodontal ligament widening, incomplete obturation of the root canal system, and periapical radiolucency was evident on the intraoral radiograph. Cone-beam computed tomography (CBCT) revealed a taurodontic and type III C-shaped root canal configuration. With a diagnosis of previous treatment and asymptomatic apical periodontitis, the patient was scheduled for root canal retreatment. The same anomaly was discovered in other molar teeth on the panoramic radiograph taken before the primary treatment of tooth #46. At a 2-month follow-up session, the tooth was found asymptomatic clinically and radiographically. The past publications about the management of nonsyndromic taurodontic molars were also reviewed. The review of 29 similar articles showed that preoperative CBCT, magnification with illumination, along with active irrigation are helpful items in managing such cases.

Radiological, histological and clinical side effects of incisor trimming in rabbits.

Incisor malocclusion in rabbits (Oryctolagus cuniculus) is a common clinical problem seen in general practice. Given that the growth rate is about 2 mm per week, a lack of wear quickly leads to feeding difficulties and soft tissue injuries. Therefore, pathologically elongated incisors must be shortened every three to six weeks. The goal of this study was to assess the potential adverse effects on dental and periodontal tissues associated with the three most commonly used trimming methods: nail cutter, diamond-coated cutting disc and diamond burr. The left mandibular incisor of 28 healthy New Zealand rabbits was subjected to four trimmings with one of the three cutting methods. After the fattening period, the mandibles were collected and both mandibular incisors were investigated on dental radiographs, micro-computed tomography scans and histological sections. Dental and periodontal tissue changes were evaluated. This study allowed a more accurate statement of the potential short-term adverse effects of the three trimming methods. At the clinical level, the nail cutter caused the formation of an irregular occlusal surface with sharp edges. Both engine-drive methods allowed the attainment of a smooth surface but the disc was less accurate. Histological evaluation revealed that the primary modifications, including coronal fractures, periodontal ligament widening and inflammation, reparative osteodentine, paracementosis and biofilm accumulation, were found in the nail cutter group.

The effectiveness of Moringa oleifera in the preservation of periodontium after radiation therapy: An experimental animal study

BackgroundRadiation therapy produces reactive oxygen species, which have been linked to various degenerative conditions in periodontal attachment. This study aimed to assess the beneficial effects of aqueous Moringa oleifera leaf extract on the periodontium of albino rats exposed to fractionated gamma radiation. Materials and methodsThis experimental study involved 24 adult male albino rats divided into three groups: Group M received M. oleifera leaf extract (300 mg/kg) intraperitoneally for 14 days; Group R received 20 Gy fractionated gamma irradiation; and Group MR received the same M. oleifera regimen as Group M and then fractionated gamma irradiation dose as Group R. On the first and seventh days post-radiation, bone, cementum, and periodontal ligament samples were histologically and histomorphometrically examined. ResultsThe periodontal ligament, alveolar bone, and cementum showed structural damage in Group R. A relative persistence of normal periodontal tissue structures was seen in Group MR, showing less disruption of the periodontal ligament and greater trabecular bone thickness than Group R. The histomorphometric analysis showed that the mean periodontal ligament width was highest in Group R7 (245.20 μm) and lowest in Group M7 (54.55 μm). In addition, the mean cementum width was highest in Group R1 (88.99 μm) and lowest in Group M1R1 (17.87 μm) and differed significantly between groups. ConclusionWithin the limitations of this study, Moringa oleifera leaf aqueous extract showed the potential to reduce the adverse effects of radiation, control inflammation, and support tissue healing in a rat model.

Comparative evaluation of effect of different premedication agents on efficacy of Articaine: A randomized contol trial.

Original Research. To comparatively evaluate the effect of different premedication agents on the efficacy of 4% Articaine in teeth with symptomatic irreversible pulpitis. The primary objective of our study is to evaluate the effect of premedication agents on efficacy of Articaine as an oral anesthetic. Our secondary objective is to comparatively evaluate the efficacy of Diclofenac patch, Ibuprofen tablet, Paracetamol tablet and Placebo as a premedication agent. Patients with 25-40 years age, no systemic disease, no history of medication for that complaint, with pain on Heft Parker Visual Analog Scale between 55mm and 170mm (VAS), no tenderness on percussion, cold test and EPT negative- Positive, giving proper consent, coming to the Department of Conservative Dentistry and Endodontics were allowed to participate. The exclusion criteria include the following- Non-vital teeth, pregnant and lactating women, allergic to Articaine and NSAIDs, active systemic disease, immune-compromised patients, taken analgesics in last 24h, root fractures, restoration extending to pulp10 and periapical pathologies (except periodontal ligament widening).Preoperatively pain was recorded using Heft Parker VAS (Visual Analog Scale). Cold testing, palpation, percussion and EPT were carried out. 40 patients having symptomatic irreversible pulpitis were randomly divided into 4 groups: group 1 Placebo (n=10), group 2-Diclofenac patch (n=10), group-3 Ibuprofen tablets (n=10), group 4-Paracetamol tablets (n=10). After 1h of premedication, all patients were administered IANB injection using 4% Articaine (Septanest with adrenaline 1/100000, Septodont, France) containing epinephrine 1:100000. 15 mins after administration of IANB, patients were asked about symptomatic numbness and was tested with Endo frost and EPT and Outcome was recorded. If lip numbness was present, Electric Pulp Testing and Cold Test give negative result then endodontic access opening was performed and pain was recorded using visual analog scale. The study was conducted for a period of 1.5 years. During the access cavity preparation only 1 subject in the Group III reported pain while in other groups none of the subjects reported pain of any type. When the intergroup comparison was made of intensity of pain 15min after LA and during access cavity preparation, the difference between the groups was statistically non-significant when analyzed using One Way ANOVA. The intragroup comparison between three time intervals revealed significant reduction in the pain scores from the pre-treatment levels in all the four groups. The results of the study showed that there is no significant effect of different premedication agents on the efficacy of 4% Articaine in teeth with symptomatic irreversible pulpitis.

Incidental Pathologic Findings from Orthodontic Pretreatment Panoramic Radiographs

Panoramic radiography is frequently performed for new patients, follow-ups and treatment in progress. This enables dental clinicians to detect pathology, view important structures, and assess developing teeth. The objective of the study was to determine prevalence of incidental pathologic findings (IPFs) from orthodontic pretreatment panoramic radiographs at a university dental hospital. A retrospective cross-sectional review was conducted of pretreatment panoramic radiographs, using data collection sheets with predefined criteria. Demographic data and abnormalities (impacted teeth, widening of periodontal ligament, pulp stones, rotated teeth, missing teeth, unerupted teeth, crowding, spacing, supernumerary teeth, and retained deciduous teeth) were reviewed. SPSS 28.0 was used to analyze data with statistical tests set at a 5% significance level. Results: One hundred panoramic radiographs were analyzed with an age range of 7 to 57 years. The prevalence of IPFs was 38%. A total of 47 IPFs were detected with altered tooth morphology predominantly (n = 17). Most IPFs occurred in males (55.3%), with 44.7% in females. A total of 49.2% were in the maxilla and 50.8% in the mandible. This difference was statistically significant (p < 0.0475). Other abnormalities were detected in 76% of panoramic radiographs; 33 with IPFs and 43 without. A total of 134 other abnormalities detected showed predominantly impacted teeth (n = 49). Most of these abnormalities were in females (n = 77). Conclusions: The prevalence of IPFs was 38%, predominated by altered tooth morphology, idiopathic osteosclerosis, and periapical inflammatory lesions. Detection of IPFs from panoramic radiographs underscored the importance for clinicians to examine them for comprehensive diagnosis and treatment planning, especially in orthodontics.

The effect of submucosal injection of platelet-rich fibrin vs. platelet-rich plasma on orthodontic tooth movement in rabbits; 28 days follow-up

This study aimed to compare between the effects of submucosal injection of platelet rich fibrin (i-PRF) versus platelet rich plasma (PRP) on orthodontic tooth movement (OTM) in a rabbit model over a 28-day follow-up period. Sixty-three rabbits were assigned into 3 equal groups. Group I animals were subjected to the OTM without any treatments and considered as the control. Whereas groups II and III were handled as group I and instead i-PRF and PRP were injected submucosally in the buccal vestibular mucosa next to the mandibular 1st premolar, respectively. The distance of OTM was consecutively measured clinically after 7, 14 and 28 days. Seven rabbits from each group were euthanized after 7, 14 and 28 days for histological evaluation. Two-way ANOVA followed by LSD post-hoc statistical tests were used for comparison. After 28 days, the mean tooth movements were 4.36±0.04mm in the control group, 6.30±0.06mm in the group receiving PRP and, 6.85±0.09mm in the group receiving i-PRF. Statistical analysis for the values of teeth movements revealed highly significant differences between different groups (P=0.001) and between different time periods (P=0.001). Histological analysis showed that submucosal injection of PRP and i-PRF yielded significant differences in periodontal ligament width in compression and tension sides between different groups (P=0.001) and between different time periods (P=0.001). Submucosal injection of either PRP or i-PRF is a minimally invasive and safe approach for accelerating OTM. In this rabbit model, the effect of i-PRF is significantly more pronounced than the effect of PRP.

The Role of Type VI Collagen in Alveolar Bone.

Many studies have been conducted to elucidate the role of Type VI collagen in muscle and tendon, however, its role in oral tissues remains unclear. In this study, an α2(VI) deficient mouse (Col6α2-KO) model was used to examine the role of Type VI collagen in oral tissues. Tissue volume and mineral density were measured in oral tissues by µCT. Proteome analysis was performed using protein extracted from alveolar bone. In addition, alveolar bone was evaluated with a periodontitis induced model. µCT analysis showed the Col6α2-KO mice had less volume of alveolar bone, dentin and dental pulp, while the width of periodontal ligament (PDL) was greater than WT. The mineral density in alveolar bone and dentin were elevated in Col6α2-KO mice compared with WT. Our proteome analysis showed significant changes in proteins related to ECM organization and elevation of proteins associated with biomineralization in the Col6α2-KO mice. In induced periodontitis, Col6α2-KO mice had greater alveolar bone loss compared with WT. In conclusion, Type VI collagen has a role in controlling biomineralization in alveolar bone and that changes in the ECM of alveolar bone could be associated with greater bone loss due to periodontitis.

Response of human periodontal ligament to orthodontic force using superb microvascular imaging

Remodeling of the periodontal ligament (PDL) during orthodontic tooth movement is closely related to the vascularity of the PDL, which has not been thoroughly investigated in humans. This study aimed to measure the width and vascular parameters of human PDL using superb microvascular imaging for the first time. Patients aged 18-25 years were selected for participation. The intervention was randomly allocated from the maxillary canines to the first molars on both sides using 50 g or 150 g of force. The width and vascular parameters of the PDL were measured using superb microvascular imaging at different time intervals (baseline, 30 minutes, and 1, 3, 7, and 14 days). Before the intervention, the width of the PDL ranged from 0.14 to 0.25 mm, and the vascular index ranged from 9.40% to 13.54%. After applying orthodontic forces, the cervical and middle PDL widths increased. The vascular index decreased slightly in 30 minutes, decreased to a minimum value after 1 day, increased to the maximum in 3-7 days, and returned to baseline values in 14 days. The values of other vascular parameters showed similar trends. The width and vascular parameters of the PDL changed slightly after force application, underwent changes in the period of reconstruction for 3-7 days, and eventually returned to baseline in 14 days.

Prevalence of apical periodontitis in endodontically-treated maxillary and mandibular posterior teeth in a Saudi Arabian population: a cone-beam computed tomography study.

The aim of this retrospective study was to assess the prevalence of apical periodontitis (AP) in root canal-treated maxillary and mandibular posterior teeth in a Saudi Arabian population based on findings from images taken using cone-beam computed tomography (CBCT). The sample included 300 CBCT images from patients (150 females and 150 males) aged between 18 and 80years old and they were analyzed to detect AP in endodontically treated maxillary and mandibular premolars and molars. Also, the correlation between the prevalence of AP and gender along with location (right/left side of jaw) were analyzed. Periapical lesions were defined as lamina dura gaps appearing disrupted around the width of periodontal ligament and apex at the apical third of the roots. There was higher prevalence of AP in maxillary (19.1%) when compared to mandibular posterior teeth (17.3%). Mandibular first and maxillary second molars were the most affected teeth with AP (P = 0.05 and P = 0.04, respectively). Also, there was higher prevalence of AP cases with a predilection toward males (Maxillary P = 0.005; Mandibular P = 0.00) and on the right side of the mandibular jaw (P = 0.03). In this study, the prevalence of AP had a significant association between gender with a predilection in males and location with a tendency to occur on the mandibular right side as observed in endodontically treated maxillary and mandibular posterior teeth using CBCT.

Utility of injectable bisphosphonates in enhancing orthodontic retention in a goat model: A split-mouth study

ObjectiveThe aim of this study was to evaluate the utility of bisphosphonates in reducing relapse after orthodontic tooth movement when injected intra-periodontally in a goat model. MethodsRight and left second incisors of four goats were extracted and the first and third incisors were approximated orthodontically and retained. A bisphosphonate gel was injected into the mesial and distal periodontal spaces of first and third incisors on one side, while the first and third incisors of the other side received normal saline as a control. After 12 weeks of retention, the orthodontic appliance was removed and teeth were relieved from any active force. Following 6 weeks from appliance removal, millimetric measurements were performed to calculate the amount of relapse of orthodontically moved incisors. Histological and microcomputed tomographic examination was performed to assess the periodontal space and surrounding alveolar bone of the study and control incisors. ResultsThe millimetric measurements and microcomputed tomographic scanning revealed that the orthodontically moved incisors in the side of bisphosphonate injection had significantly less relapse (p ≤ 0.05) and significantly narrower periodontal ligament width (p ≤ 0.05) than in the control side, respectively. Histologically, newly formed bone projecting into the periodontal ligament was observed in the side of bisphosphonate injection with newly formed cementum overlying areas of resorbed cementum. ConclusionThe results suggest that bisphosphonate injection has the potential to enhance post-orthodontic stability and repair of root resorption following orthodontic treatment.

Clinical and radiographic effectiveness of mineral trioxide aggregate (MTA) partial pulpotomy with low power or high power diode laser irradiation in deciduous molars: a randomized clinical trial.

This study investigated the clinical and radiographic effectiveness of MTA partial pulpotomy with low power or high power diode laser irradiation in primary molars. In this randomized single-blind clinical trial, 63 mandibular second molars were assigned into three groups (n = 21). After pulp amputation and achieving hemostasis, MTA was placed over pulp stumps in group 1 (MTA). The patients in groups 2 (LLLT-MTA) and 3 (DL-MTA) underwent low level (660nm, 200 mW) and high power (810nm, 1W) diode laser radiation prior to MTA placement, respectively. The occurrence of clinical failure (spontaneous pain, tenderness upon percussion, swelling, fistula, mobility) and radiographic failure (periodontal ligament widening, external or internal root resorption, periapical or furcal radiolucency) was recorded up to 18months after therapy.MTA and LLLT-MTA groups showed clinical success rate of 100% throughout the experiment. The clinical success rate of DL-MTA group was 95.2%, 95.2%, and 87.5% after 6, 9, and 18months. The radiographic success rates were 90.5%, 90.5%, and 87.5% in the MTA group; 100%, 95.2%, and 88.2% in the LLLT-MTA group, and 85.7%, 76.2%, and 68.7% in the DL-MTA group, at 6-, 9-, and 18-month follow-ups, respectively. No significant differences were found in the frequency of clinical or radiographic failure among the groups at any interval (p > 0.05). MTA partial pulpotomy was a suitable technique for vital pulp therapy in deciduous teeth. The addition of low power or high power diode laser radiation to the procedure did not cause a significant difference in success rate values.

Bio-hybrid dental implants prepared using stem cells with β-TCP-coated titanium and zirconia.

PurposeThis study investigated periodontal ligament (PDL) restoration in osseointegrated implants using stem cells.MethodsCommercial pure titanium and zirconium oxide (zirconia) were coated with beta-tricalcium phosphate (β-TCP) using a long-pulse Nd:YAG laser (1,064 nm). Isolated bone marrow mesenchymal cells (BMMSCs) from rabbit tibia and femur, isolated PDL stem cells (PDLSCs) from the lower right incisor, and co-cultured BMMSCs and PDLSCs were tested for periostin markers using an immunofluorescent assay. Implants with 3D-engineered tissue were implanted into the lower right central incisors after extraction from rabbits. Forty implants (Ti or zirconia) were subdivided according to the duration of implantation (healing period: 45 or 90 days). Each subgroup (20 implants) was subdivided into 4 groups (without cells, PDLSC sheets, BMMSC sheets, and co-culture cell sheets). All groups underwent histological testing involving haematoxylin and eosin staining and immunohistochemistry, stereoscopic analysis to measure the PDL width, and field emission scanning electron microscopy (FESEM). The natural lower central incisors were used as controls.ResultsThe BMMSCs co-cultured with PDLSCs generated a well-formed PDL tissue that exhibited positive periostin expression. Histological analysis showed that the implantation of coated (Ti and zirconia) dental implants without a cell sheet resulted in a well-osseointegrated implant at both healing intervals, which was confirmed with FESEM analysis and negative periostin expression. The mesenchymal tissue structured from PDLSCs only or co-cultured (BMMSCs and PDLSCs) could form a natural periodontal tissue with no significant difference between Ti and zirconia implants, consequently forming a biohybrid dental implant. Green fluorescence for periostin was clearly detected around the biohybrid implants after 45 and 90 days. FESEM showed the invasion of PDL-like fibres perpendicular to the cementum of the bio-hybrid implants.Conclusionsβ-TCP-coated (Ti and zirconia) implants generated periodontal tissue and formed biohybrid implants when mesenchymal-tissue-layered cell sheets were isolated from PDLSCs alone or co-cultured BMMSCs and PDLSCs.

Management of Compromised First Permanent Molar with Triple Antibiotic Paste in a 12-year-old Child: A Case Report

In teeth with pulpal and periapical infection, various group of microorganisms are present. Inhibition of the growth of these microorganisms and suppression of their antimicrobial activity play a crucial role in the success of the endodontic management. Triple antibiotic paste has been reported to have an excellent antimicrobial efficacy and it can be useful in management of teeth with severe infection. A 12-year-old female child reported with pain and swelling in relation with a lower left first permanent molar. Clinical examination of the tooth revealed deep occlusal caries and dentoalveolar abscess. Radiographically, the carious lesion was seen involving the pulp with periodontal ligament widening and inter-radicular bone loss was observed (endo-perio lesion). Considering the position of the tooth and its strategic importance, a conservative approach to salvage the tooth using Triple Antibiotic Paste (TAP) as a medicament was employed with complete radiographic healing by 12 weeks. Subsequent obturation using lateral condensation with gutta percha followed by composite restoration and preformed stainless steel crown was performed. This case report focuses on the endodontic management of perforated first permanent molar with compromised periodontal support and significant bone loss TAP as medicament and Mineral Trioxide Aggregate (MTA) as perforation repair material. Based on the results it can be concluded that Triple Anitibiotic Paste (TAP) can be effective in the disinfection and sterilization of the root canals and repair of complex lesions.