Present status and future directions:Apexification

The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each case.The main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and techniques.Future research on apexification should focus on how to treat open apices with wide periapical lesions without surgery.Previously,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more predictable.Another reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.

Microscopic removal of type Ⅲ dens invaginatus and preparation of apical barrier with mineral trioxide aggregate in a maxillary lateral incisor:A case report and review of literature

BACKGROUND Invaginated teeth pose greater challenges in clinical management because of their complex configuration.With advancements in equipment and materials,such as the dental operation microscope,cone-beam computed tomography and mineral trioxide aggregate,the preservation rate of type Ⅲ dens invaginatus could be greatly increased.CASE SUMMARY This case report presented a 31-year-old woman with complaints of spontaneous swelling and pain in the right maxillary lateral tooth.With the aid of cone-beam computed tomography,type Ⅲ dens invaginatus with apical periodontitis was diagnosed and confirmed.Three-visit endodontic treatment was performed.In the first visit,the invagination was carefully removed under the dental operation microscope,and chemomechanical preparation was done.In the second visit,mineral trioxide aggregate apical barrier surgery was performed in this tooth.In the third visit,the canal was finally obturated with thermoplastic gutta-percha to recover the crown morphology.A 26-mo follow-up revealed a satisfied outcome both in the radiographic and oral examinations.CONCLUSION In this case,removal of the entire abnormal structure provided great convenience for the follow-up treatment.When confronted with the same clinical case in the future,we can take a similar approach to address it.

Antibacterial activity of calcium hydroxide combined with chitosan solutions and the outcomes on the bond strength of RealSeal sealer to radicular dentin

The purpose of this study was to investigate the antibacterial activity of calcium hydroxide [Ca（OH）2] combined with chitosan solutions against Enterococcus faecalis-infected root canal dentin and the effect of this new intraca- nal medicament on the bond strength of RealSeal sealer to radicular dentin. An experimental intracanal medicament was prepared by mixing different concentrations of chitosan solution （25%, 50%, and 100%, W/V） to Ca（OH）2 powder. Antibacterial activity was evaluated and the total numbers of colony forming units were determined. Bonding ability of RealSeal sealer to radicular dentin was evaluated using push-out bond strength test. Data were analyzed using one-way analysis of variance （ANOVA） and Tukey＇s multiple comparison tests. We found that Ca（OH）2 combined with different concentrations of chitosan solutions showed better antibacterial activity than Ca（OH）2 mixed with saline, without significantly affecting the bond strength of RealSeal sealer to radicular dentin （P 〉 0.05）. The findings suggest that Ca（OH）2 combined with chitosan is a promising intracanal medicament and may be effective in endodontic therapy.

Non-surgical management of dens invaginatus type IIIB in maxillary lateral incisor with three root canals and 6-year follow-up:A case report and review of literature

BACKGROUND The presence of dens invaginatus(DI)complicates treatment of any tooth,from diagnosis to access cavity and biomechanical preparation and obturation.Reports of successful non-surgical management of DI type IIIB in maxillary lateral incisor are rare.Here,we report such a case,with three root canals and a long follow-up.CASE SUMMARY A 13-year-old female patient presented with mild pain in the maxillary right lateral incisor(#7)for 10-15 d.On examination,the tooth was slightly rotated,with slight tenderness on percussion and grade I mobility but with no caries,pockets or restorations and non-vital pulp(via vitality tests).Radiographic examination revealed unusual configuration of the tooth’s root canals,with an enamel-lined invagination extending to the apex,suggesting the possibility of DI Oehler’s type IIIB and a periapical radiolucency.Widening the access cavity lingually revealed one distinct buccal orifice and two distinct palatal orifices;under higher magnification of a dental operating microscope(DOM),the mesio palatal and disto-palatal orifices were observed as connected by a C-shaped groove.The root canals were prepared with hand K-files following a step-back technique,and obturated using a combination technique of lateral condensation and vertical compaction.At the 6-year follow-up,the patient was asymptomatic,and the periapical radiography displayed significant healing around the apical end of the root.CONCLUSION Proper knowledge of unusual root canal anatomy is required in treating DI.Conventional methods of root canal treatment can successfully resolve such complex cases,facilitated by DOM and cone-beam computed tomography.

HSP25 Affects the Proliferation and Differentiation of Rat Dental Follicle Cells

Aim To detect the expression of HSP25 in rat dental follicles both in vivo and vitro, and explore the underlying mechanism of HSP25 on the proliferation and differentiation of rat dental follicle cells （DFCs）. Methodology Immunohistochemistry was performed to detect the expression of HSP25 in mandibles of postnatal rats on days 1, 3, 5, 7, 9 and 11 in vivo. In vitro, the expression of HSP25 in DFCs was detected by an indirect immunofluorescence assay. Thiazolyl blue tetrazolium bromide （MTT） assay, flow cytometry and alkaline phosphatase （ALP） assay were used to identify the time-course effect mediated by different concentrations of recombinant murine HSP25 of 0, 1, 10, 50 and 100 ng/mL on rat DFCs. Results Expression of HSP25 was not detected in dental follicles of the rats until day 5 after birth, but became up-regulated in a time-dependent manner till day 11. HSP25 was detected in the cytoplasm of cultured rat DFCs. No significant difference could be observed in the proliferation of DFCs after stimulation with different concentrations of HSP25 on days 1, 2 and 3 （P〉0.05）. HSP25 at concentrations of 50 ng/mL and 100 ng/mL up-regulated the ALP activity of DFCs on day 9 （P〈0.05）. Conclusion HSP25-immunoreactivity increased chronologically during the development of dental follicles. The protein had no significant effect on cell proliferation but may play a role in cementoblast/osteoblast differentiation of DFCs.

Effect of addition of chitosan to self-etching primer:antibacterial activity and push-out bond strength to radicular dentin

The purpose of this study was to evaluate the antibacterial activity of a modified self-etching primer incorporating chitosan and whether this modification affected the bond strength to radicular dentin.A modified self-etching primer was prepared by adding chitosan solutions at 0.03%,0.06%,0.12% and 0.25%（W/W） to RealSeal selfetching primer.RealSeal primer without chitosan was used as the control.The antibacterial activity of the modified self-etching primer was evaluated using the direct contact test against Enterococcus faecalis.The bonding ability of the RealSeal system to radicular dentin was evaluated using the push-out bond strength test.The modes of failure were examined under a stereomicroscope.Data were analyzed using analysis of variance（ANOVA） and Tukey’s test,with a P-value 〈 0.05 indicating statistical significance.The results showed that the antibacterial properties of the freshly prepared and aged modified self-etching primer incorporating chitosan exhibited potent antibacterial effect against Enterococcus faecalis compared with the unmodified primer.The RealSeal system with the aged modified self-etching primer incorporating chitosan showed no significant differences in the bond strength as compared with the control（P = 0.99）.The findings suggest that modified self-etching primer incorporating chitosan is a promising antibacterial primer which does not adversely affect the bond strength of the RealSeal system to radicular dentin.

A comparative evaluation of dentin caries removal with polymer bur and conventional burs—An <i>in vitro</i>study

Aim: To evaluate the comparative efficacy of Polymer bur (Smartprep) and Conventional burs (Carbide bur & Diamond Points) in selective Dentin caries removal. Materials and method: 15 freshly extracted carious human premolars and molars were selected for this study. These teeth were split in the center of carious lesion, in order to obtain two corresponding half. Thus 30 samples were prepared in this way. These were randomly divided in to 3 groups of 10 samples each. Group 1: The carious portion of these samples was excavated with the help of polymer bur Smartprep (SS White). Group 3: Prepared with Tungsten carbide round bur (No. 018). Group 3: Prepared with the help of Diamond points (No. 018). The period of time involved in this process is measured. After excavation of all carious lesions, a longitudinal section from mid most part of lesion was obtain with the help of diamond disc at slow speed. After staining with caries detector dye “Seek”, the sections were subjected to histological evaluation under stereomicro-scope. The thickness of remaining caries is measured in more or less than 1 mm. Results: The difference in grading of remaining carious dentin between Polymer bur and Conventional burs were statistically non- significant, but Polymer bur taken more time in comparison to Conventional burs. Conclusion: Smartprep bur is more conservative in selectively dentin caries removal than Conventional burs but same time it is more time consuming than Conventional burs.

Expert consensus on endodontic therapy for patients withsystemic conditions

The overall health condition of patients significantly affects the diagnosis, treatment, and prognosis of endodontic diseases. Asystemic consideration of the patient’s overall health along with oral conditions holds the utmost importance in determining thenecessity and feasibility of endodontic therapy, as well as selecting appropriate therapeutic approaches. This expert consensus is acollaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence,aiming to provide general guidance on clinical procedures, improve patient safety and enhance clinical outcomes of endodontictherapy in patients with compromised overall health.

Advancing engineered approaches for sustainable wound regeneration and repair:Harnessing the potential of green synthesized silver nanoparticles

Wound healing is a crucial biological process for tissue repair and regeneration,preventing infections and com-plications.There’s been a growing interest in exploring sustainable wound healing strategies in recent years.This review examines the use of green-synthesized silver nanoparticles(AgNPs)in sustainable wound healing strate-gies.It highlights the need for innovative approaches and the challenges posed by infections.The current wound therapies and treatments,highlighting gaps in existing methodologies,are evaluated.This review provides a com-prehensive overview of the current state-of-the-art in green synthesis techniques for the synthesis of AgNPs.The properties and characterization of AgNPs are elucidated,providing insights into their efficacy.The biocompati-bility of AgNPs in wound healing is also explored,emphasizing safety in medical applications.Green synthesized AgNPs incorporated wound dressings are detailed,showcasing their potential in clinical settings.Challenges and future perspectives are discussed,addressing hurdles to widespread implementation.The conclusion consolidates key findings,offering a synthesized perspective on the potential of green-synthesized AgNPs in revolutionizing current knowledge on innovative approaches for sustainable wound healing practices.

Recent advances in imaging technologies in dentistry

Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the simple intra-oral periapical X-rays, advanced imaging techniques like computed tomography, cone beam computed tomography, magnetic resonance imaging and ultrasound have also found place in modern dentistry. Changing from analogue to digital radiography has not only made the process simpler and faster but also made image storage, manipulation(brightness/contrast, image cropping, etc.) and retrieval easier. The three-dimensional imaging has made the complex cranio-facial structures more accessible for examination and early and accurate diagnosis of deep seated lesions. This paper is to review current advances in imaging technology and their uses in different disciplines of dentistry.

Bilateral maxillary fused second and third molars:a rare occurrence

This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography （CBCT）. A 31-year-old Chinese male, with no contributory medical or family/social history, presented with throbbing pain in the maxillary right molar area following an unsuccessful attempted tooth extraction. Clinical examination revealed what appeared initially to be a damaged large extra cusp on the buccal aspect of the distobuccal cusp of the second molar. However, CBCT revealed that a third molar was fused to the second molar. Unexpectedly, the maxillary left third molar also was fused to the second molar, and the crown of an unerupted supernumerary fourth molar was possibly also fused to the apical root region of the second molar. Operative procedures should not be attempted without adequate radiographic investigation. CBCT allowed the precise location of the root canals of the right maxillary fused molar teeth to permit successful endodontic therapy, confirmed after 6 months.

Salivary gland disorders:A comprehensive review

Salivary glands are complex in nature. They could be either tubulo acinar, merocrine or exocrine glands secreting mainly saliva. Salivary gland is one of the main soft tissue structures in the maxillofacial area. Saliva is a clear, slightly acidic muco serous fluid that coats the teeth, mucosa and thereby helps to create and maintain a healthy environment in the oral cavity. Salivary glands may be affected by a number of diseases: local and systemic and the prevalence of salivary gland diseases depend on various etiological factors. The glands may be infected byviral, bacterial, rarely fungal or its ductal obstruction which may cause painful swelling or obstruction, affecting their functions. The salivary gland may also be affected by a various benign and malignant tumours. This review article briefly describes about the various salivary gland disorders, diagnostic techniques and their management including the recent advances and the future perspective.

Clinical Management of Mid-Root Fracture in Maxillary Central Incisors:Case Reports

Management of mid-root fractures presents a formidable challenge for clinicians because of the difficulty of achieving a stable reunion of fracture fragments. This article presents two varied treatment options for mid-root fractures. A 15-year-old female reported an impact injury to the maxillary anterior teeth 2 days after its occurrence. Clinically,the maxillary left central incisor was palatally-extruded with a negative vitality response and radiographic evidence of an oblique fracture at the middle third of the root. An endodontic implant was employed which utilized an open technique and has been on follow-up for ten months. A 32-year-old male reported an injury,which resulted in a mobile maxillary right central incisor,three months after its occurrence. Through clinical and radiographic means,a discolored,extruded,and non-vital maxillary right central incisor with an oblique root fracture at the alveolar-crest level was observed. Exploratory surgery was performed; an apical barrier was created with a mineral trioxide aggregate and obturated with gutta percha. The fragments were stabilized with a fiber post and patient has been on follow-up for five months. Short-term follow-up for both of the cases showed promising results both clinically and radiographically.

Ameloblastic carcinoma: Report of a rare case

Ameloblastic carcinoma is a rare odontogenic tumor exhibiting histological evidence of malignancy in the primary or recurrent tumor. It is characterized by rapid, painful expansion of the jaw, unlike conventional ameloblastomas. The tumor most frequently involves the mandible. The expanding lesion causes perforation of the buccal and lingual plates of the jaw and invades the surrounding soft tissue. Rapidly growing large tumor mass may cause tooth mobility. A mandibular tumor involving the mental nerve leads to paresthesia of the nerve. A maxillary tumor can produce a fistula in the palate and paresthesia of the infraorbital nerve. Most ameloblastic carcinomas are presumed to have arisen de novo with a few cases of malignant transformation of ameloblastomas. Although rare, these lesions have been known to metastasize, mostly to the regional lymph nodes or lungs. A case of ameloblastic carcinoma in a 60-year-old man is reported here and its clinical, radiological and histological features are discussed.

Antimicrobial effect of <i>Anacardium occidentale</i>leaf extract against pathogens causing periodontal disease

The oral cavity is perpetually colonized by different species of microorganisms and at times it is difficult to characterize the periodontal pathogen causing breakdown of tissue and bone. But over the years, based on scientific knowledge, it has been observed that various gram negative anaerobic bacteria have been involved with the initiation of periodontal disease. Based on literature reviews, a study was undertaken to investigate the antimicrobial effect of Anacardium occidentale (cashew) leaf extract on Porphyromonas gingivalis and Prevotella intermedia. Methanol and aqueous extracts of cashew leaves were prepared. Its antimicrobial activity against P. gingivalis and P. intermedia was tested using the agar diffusion method at various dilutions of 75 μ, 50 μl, 25 μl, 10 μl and 5 μl respectively. 0.2% Clorhexidine gluconate (CHX) was used as control. Cultures of P. gingivalis and P. intermedia strains were maintained on Kanamycin blood agar. The agar plates were then incubated at 37?C for 72 hours after which the zone of inhibition was measured and the mean was recorded for each test solution. The results of this study demonstrated that, for both P. gingivalis and P. intermedia, the highest concentration (75 μl) of both the extracts showed maximum antimicrobial action. For P. ginigvalis, the aqueous extract demonstrated significant inhibitory activity compared to the methanolic extract (p = 0.005), which was comparable to that of CHX. For P. intermedia, similar results were observed with aqueous extract being more effective compared to methanolic (p = 0.007), however, CHX was most effective compared to both the extracts (p = 0.007). This study revealed that Anacardium occidentale leaf extracts have efficient antimicrobial activity against P. gingivalis & P. intermedia. Hence, this preliminary study suggests that the antimicrobial action of A. occidentale leaf could be utilized for the preparation of chemical plaque control formulations.

Pulp Revascularization: Future Therapy of Tooth with Open Apex

Introduction: The endodontic management of necrotic permanent immature teeth is a challenge for the practitioner. These teeth are treated by apexification. However, because of the complications associated with this treatment, researchers have developed other therapies. Currently, a new technique called pulp revascularization has emerged. This technique allows the continuation of root completion thanks to a healthy tissue newly formed at the intra root canal level. Material and method: A literature search of articles dealing with pulp revascularization of immature permanent teeth was conducted using two types of search strategy, a literature search using keywords on databases and then a manual “bottom-up” search of references of previously identified articles. Results: 112 articles were identified based on inclusion and exclusion criteria. Discussion: This work showed that pulp revascularization is a new therapy that aims to restart root development on an immature permanent tooth. It is based on the principle of tissue engineering and uses the differentiation potential of stem cells. Conclusion: Currently, the literature values revascularization as it allows root development, sidewall thickening, apical closure and a decrease in periapical lesion and ensures a good sealing. Clinical and radiographic success rates appear to be encouraging, except that factors influencing treatment must be taken into consideration.

Controversy of silver amalgam as a restorative material

Silver amalgam contains mercury leading to concerns about the potential toxic effects of amalgam on the health of dental patients. The debate over the toxicity of silver amalgam restorations has divided the dental profession for over a century. The use of amalgam restorations for anterior teeth have been declining worldwide due to patient's safety concerns and preference for tooth colored restorations. Nevertheless, amalgam has served the dental profession for decades and benefited hundreds of millions of patients because of its longevity as a dental restorative material. Amalgam is still the World's most widely used restorative material for posterior teeth.

A survey of analgesic and anti-inflammatory drug prescription for oral implant surgery

Aim:This study was conducted to determine the preferred analgesic and anti-inflammatory drugs prescribed by oral implantologists in India.Methods:A structured questionnaire was distributed to 332 dentists to gather information regarding their prescription habits for analgesics and anti-inflammatory drugs.Frequency distributions were computed by type of drug being prescribed and the protocol followed.Results:Analysis of data showed that majority of dentists(85.8%,n=285)prescribed conventional non-steroidal anti-inflammatory drugs(NSAIDs)for implant surgery.The most common prescription was ibuprofen with paracetamol combination(32.2%,n=107)followed by diclofenac(20.2%,n=67).Most dentists reported prescribing different NSAIDs for the same procedure in different patients(64.7%,n=215).Only,35.5%(n=118)followed the peri-operative protocol.Adjunctive prescription of steroids was done by only 33.7%(n=112).Conclusion:Our study illustrates that the general trend of analgesic and anti-inflammatory drug prescription for dental implant surgery among Indian dentists is mostly in accordance with the guidelines for pain management worldwide.However,it is noteworthy that a few dentists do prescribe drugs not primarily indicated for dental pain management and use widely varying protocols for the same.Therefore,in order to avoid potential complications,it is essential to raise awareness of among the dental practitioners of the appropriate indications and dosage regimen of specific drugs.

Wnt and BMP signaling crosstalk in regulating dental stem cells:Implications in dental tissue engineering

Tooth is a complex hard tissue organ and consists of multiple cell types that are regulated by important signaling pathways such as Wnt and BMP signaling.Serious injuries and/or loss of tooth or periodontal tissues may significantly impact aesthetic appearance,essential oral functions and the quality of life.Regenerative dentistry holds great promise in treating oral/dental disorders.The past decade has witnessed a rapid expansion of our understanding of the biological features of dental stem cells,along with the signaling mechanisms governing stem cell self-renewal and differentiation.In this review,we first summarize the biological characteristics of seven types of dental stem cells,including dental pulp stem cells,stem cells from apical papilla,stem cells from human exfoliated deciduous teeth,dental follicle precursor cells,periodontal ligament stem cells,alveolar bone-derived mesenchymal stem cells(MSCs),and MSCs from gingiva.We then focus on how these stem cells are regulated by bone morphogenetic protein(BMP)and/or Wnt signaling by examining the interplays between these pathways.Lastly,we analyze the current status of dental tissue engineering strategies that utilize oral/dental stem cells by harnessing the interplays between BMP and Wnt pathways.We also highlight the challenges that must be addressed before the dental stem cells may reach any clinical applications.Thus,we can expect to witness significant progresses to be made in regenerative dentistry in the coming decade.

Fatigue resistance of ProTaper gold exposed to high-concentration sodium hypochlorite in double curvature artificial canal

This study aimed to evaluate and compare the fatigue resistance of ProTaper Gold(PTG)and ProTaper Universal(PTU)in artificial single and double curvature canals in 5%sodium hypochlorite(NaOCl)at body temperature(37℃).PTG and PTU files(size F1)were subjected to fatigue tests in two different artificial ceramic canals.The single curvature model had a 60°curvature angle with a 5mm radius.The double curvature model had a 60°curvature angle with a 5mm radius and a second 30°curvature with a 2mm radius.A file segment was introduced into the artificial canal and immersed in water or 5%NaOCl at 37℃.The total number of cycles to fracture(NCF)was recorded.Data were analyzed using t-test and linear regression analysis.The NCF of all files was significantly influenced by the type of NiTi metal alloy(P<.01),canal curvatures(P<.01),and the environmental conditions(P<.05).PTG had higher fatigue resistance than PTU files in both single and double curvature canals(P<.05).The NCF of PTU files in 5%NaOCl was shorter than that in water(P<.05).The mean length of broken PTG was significantly shorter than those of PTU files in both single and double curvature canals(P<.01).The fatigue performance of PTG is better than that of PTU in both single and double curvature.Environmental conditions may affect the fatigue behavior of PTU files with single curvature.