Non-setting Calcium Hydroxide Research Articles

Case series on two-stage disinfection in regenerative endodontics on permanent mandibular molar with blunderbuss canal

Background: Revascularization is a promising approach as it promotes root end closure forming healthy, thick root dentin at the apex which provides clinical and radiographic success due to the elimination of bacteria and disinfection of the canal which gives a 100% sterile environment to receive SCAP. Aim: To examine the effect of a regenerative endodontic procedure on immature necrotic teeth with apical periodontitis Method: An 8-year-old medically fit boy was referred to the department with a lingering type of pain in the immature permanent mandibular first right molar. Bleeding was induced in the root canals at the third appointment. The blood clots (scaffolds) were covered with MTA, and the tooth was restored with a composite filling. Recall sessions were scheduled after one month and 3 months, when the tooth appeared asymptomatic clinically and radiographically, with considerable periapical healing. Conclusion: An immature multirooted tooth with necrotic pulps and periapical radiolucency was managed with evident clinical and radiographic success, wherein non-setting calcium hydroxide paste and triple antibiotic paste were used sequentially to guarantee complete canal disinfection.

Outcome of Regenerative Endodontic Procedures in Nonvital Immature Permanent Teeth Using 2 Intracanal Medications: A Prospective Randomized Clinical Study

IntroductionThis randomized clinical trial aimed to assess and compare the long-term clinical and radiographic outcomes of regenerative endodontic procedures (REPs) in treating nonvital immature permanent teeth using 2 intracanal medicaments. MethodsForty-five patients yielding a total of 50 anterior and posterior nonvital immature teeth were randomly divided into 2 groups. REPs using either nonsetting calcium hydroxide (Ca[OH]2) (n = 25) or modified triple antibiotic paste (TAP) (n = 25) as intracanal medicaments were performed. NeoMTA Plus (Avalon Biomed Inc) was applied for coronal sealing. Cases were followed up clinically and radiographically for 36 months. The survival rate, success rate, and clinical outcome measures were analyzed. Preoperative and recall radiographs were evaluated for dimensional changes in root length, dentin thickness, apical diameter, and periapical radiolucency. ResultsAt the 36-month follow-up, the success and survival rates were 81.6% and 100%, respectively, in which 79.4% of cases showed complete resolution of periapical radiolucency with no significant difference between the nonsetting Ca(OH)2 and modified TAP groups (P > .050). The cumulative changes in root length, root dentin thickness, and apical diameter throughout the study period were observed in 47.9%, 77.1%, and 89.6% of cases, respectively, with no significant differences between groups (P ≥ .39). Intracanal calcifications were detected in 60% of cases with no significant difference between groups (P = .77). ConclusionsREPs, using either nonsetting Ca(OH)2 or modified TAP as the intracanal medicament, exhibited high success and survival rates over a follow-up period of 36 months with equally favorable clinical and radiographic outcome data.

Effect of Non-Setting Calcium Hydroxide on the Healing of Periapical Lesions: A Systematic Review

Summary: Periapical lesions, inflammatory reactions caused by bacterial infections in the periapical area of teeth, require effective treatment for optimal healing. Non-setting Ca (OH)2 has been utilized as a medicament in endodontic procedures to promote the healing of periapical lesions. This systematic review aims to evaluate the effect of non-setting calcium hydroxide on the healing of periapical lesions. Non-setting calcium hydroxide is commonly used in endodontic procedures for its antimicrobial and tissue-healing properties. Understanding its effectiveness in promoting periapical lesion healing is crucial for clinical decision-making and improving patient outcomes. A comprehensive literature search was conducted using electronic databases (PubMed, Embase, and Cochrane Library) to identify relevant studies published up to September 2021. The search strategy included keywords related to non-setting calcium hydroxide, periapical lesions, endodontic treatment, and healing. Both experimental and clinical studies assessing the effect of non- setting calcium hydroxide on periapical lesion healing were included. Data were extracted and assessed for quality and bias using appropriate tools. The initial search yielded a total of 378 articles, of which 12 studies met the inclusion criteria. The studies included in this review consisted of both in vitro and in vivo experimental models, as well as clinical trials. The outcomes assessed varied among the studies, including radiographic evaluation, histological analysis, and clinical examination. The majority of the included studies reported positive effects of non-setting calcium hydroxide on periapical lesion healing. These effects were attributed to its antimicrobial activity, promotion of tissue repair, and induction of mineralized tissue formation. Based on the available evidence, non-setting calcium hydroxide appears to have a beneficial effect on the healing of periapical lesions. However, due to the heterogeneity ...

In-vitro Comparison of Antibacterial Activities on Stingless Bee Propolis using Selected Extraction Methods

This study aimed to compare the different selected extraction methods of propolis extracts against Enterococcus faecalis (E. faecalis). Extraction of Malaysian Propolis (MP) from Heterotrigona itama, was carried out using 70% ethanol. For the selected extraction processes, such as, centrifugation-assisted extraction (CAE), vacuum-assisted extraction (VAE), and shaking-assisted extraction (SAE) methods were used. Antimicrobial activity against E. faecalis was assessed using the antibacterial susceptibility test (AST). The results showed that SAE, followed by CAE, had better antimicrobial properties as compared to those obtained by VAE. The inhibition zones for SAE, CAE, and VAE were 5.3mm, 4.67mm, and 4.16mm, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for extracted MP by SAE were 12.5 and 25 mg/mL, respectively. Furthermore, non-setting calcium hydroxide’s [Ca(OH)2] MIC and MBC were determined to be 50 and 100 mg/mL, respectively. As a result, we believe that extraction of raw MP from Heterotrigona itama using the SAE method was more effective than Ca(OH)2 against E. faecalis.

English

Calcium hydroxide is used as an intracanal medicament in endodontics as it reduces intracanal microbial load and exudate discharge from infected teeth. Reports have shown that extrusion of calcium hydroxide periapically leads to an increased incidence of swelling, delayed periapical healing, nerve paraesthesia and other complications. Teeth with immature apex or those undergoing apical resorption are prone to higher chances of periapical medicament extrusion, especially under high pressure delivery systems. This case report discusses nonsurgical management of periapically extruded non-setting calcium hydroxide by an innovative technique which is less invasive and comfortable both for the clinician and the patient. Calcium hydroxide is widely used as an intracanal medicament for the treatment of pulpal and periapical diseases.1 The intracanal placement of calcium hydroxide can be done with a lentulospiral or a syringe-based delivery system.2 If extruded periapically, there is an increased incidence of swelling, delayed periapical healing, nerve paraesthesia and other complications.3 Case reports in the past have suggested surgical management of periapically extruded calcium hydroxide. The purpose of this case report is to discuss an orthograde nonsurgical management of periapically extruded calcium hydroxide based intracanal medicament containing barium sulphate during endodontic treatment.

Revascularization of an Immature Necrotic Mandibular Second Molar Using Calcium Hydroxide: A 3-year Follow Up

Endodontic intervention in necrotic immature permanent teeth is usually a clinical challenge. With appropriate case selection and optimal disinfection, regenerative endodontic procedure (REP) can be effective and a desirable result can be obtained. In this report, an immature necrotic mandibular second molar had been treated by REP in two visits. In the first visit, a nonsetting calcium hydroxide was used as intracanal medication after irrigation with 1.5% (NaOCl). In the second visit, blood clots were created in the root canals. MTA was placed over the blood clots and the tooth was restored with a composite filling and stainless-steel crown. A clinical and radiographic follow up was performed for three years where the tooth was deemed a symptomatic with a complete root formation.

Regenerative Endodontic Procedures, Disinfectants and Outcomes: A Systematic Review.

This systematic review aims to identify and synthesise available evidence to determine the clinical and radiographic outcomes of REP involving any disinfection irrigant together with a non-antibiotic intracanal medicament. Experimental and observational studies evaluating the outcomes of REP in immature non-vital permanent teeth in 6-16 year olds, where the protocol used any type of disinfectant irrigant together with a non-antibiotic intracanal medicament (non-setting calcium hydroxide) were included. Data was narratively synthesised and presented in respect to the primary outcome (elimination of symptoms and infection) and secondary outcomes (increase in root length/width; positive response to vitality testing; patient-reported outcomes; adverse effects). 1628 studies were identified, of which five met the eligibility criteria for inclusion in the review. Studies included one randomised control trial and four observational studies. All five studies showed an absence of clinical signs and symptoms for all teeth postoperatively with radiographic resolution or absence of pathology following the disinfection stages of the REP used. Choice of secondary outcomes were inconsistent but included further root development, coronal discolouration and root canal calcifications postoperatively. There was a high risk of bias in all five studies and subsequently the quality of the evidence base was judged to be low. REP using a non-antibiotic disinfectant approach appears capable of providing satisfactory outcomes for a non-vital immature permanent tooth. Further high-quality research is required before solid recommendations towards clinical practice guidelines for the disinfection portion of REP can be implemented.

Undergraduate endodontic clinical training in Malaysia: A National survey.

Online survey was conducted to investigate the state of undergraduate endodontic clinical training in Malaysian dental schools. An online questionnaire and a cover letter were emailed to the deans of 13 Malaysian dental schools. The questionnaire covers various aspects of endodontic clinical training including teaching methods, endodontic clinical procedures, minimum requirements, clinical sessions and teaching staff. The response rate was 69%. Similarities in teaching methods were observed in all responding schools. All schools taught contemporary root canal treatment procedures, including the utilisation of radiograph and electronic apex locator for working length determination, the crown-down approach for canal preparation and the cold lateral compaction for obturation. Sodium hypochlorite solution and non-setting calcium hydroxide medicament were used in most dental schools. Variations were observed in terms of the number of clinical requirements, supervisor: student ratio, and availability of endodontic specialists. The use of engine-driven instruments was observed mainly in government-funded dental schools. The majority of dental schools in Malaysia are adopting the European Society Endodontology recommendation for undergraduate endodontic training, particularly in relation to the surveyed aspects. Most of the government-funded dental schools have progressed towards engaging contemporary endodontics with their increasing application of engine-driven Ni-Ti instruments and 3D imaging techniques. Appointments of full-time endodontic specialists would further enhance the quality of endodontic teaching and permit the utilisation of contemporary endodontic materials.

Time-Dependent Effect of Different Intracanal Medicaments on Dentin Microhardness and Dislocation Resistance of MTA Used During Regenerative Endodontic Treatment

Objectives: This study was designed to measure and compare dentin microhardness and MTA (ProRoot, Dentsply Tulsa Dental, Tulsa, OK) dislocation resistance (DR) used in regenerative endodontic treatment (RET) after application of three different intracanal medication(ICM) for 2,4 and 12 weeks’ time intervals. Material and methods: One-hundred sixty eight human maxillary central incisors were selected for the study. Teeth were cut apically 12 mm below and coronally 2 mm above the cemento-enamel junction. Canals were instrumented up to instrument F5 (ProTaper Universal, Dentsply Maillefer, Ballaigues, Switzerland), then Peeso drills (Mani, Tochigi, Japan) were used from No. 1 up to No. 6 , passing 1 mm beyond the apical foramen to obtain larger root canals. Between every 2 consecutive instruments 2 mL of 2.5% sodium hypochlorite (NaOCl) used for canals irrigation , final flush using 5 mL of 2.5% NaOCl and 5 mL of 17% ethylene-diamine-tetra-acetic acid (EDTA, Sigma) followed by 10 mL of distilled water. Samples were randomly divided according to the type of the ICM used inside the canal into 4 equal groups (n = 42); Group 1: Double antibiotic past(DAP) paste: 1:1 mixture of ciprofloxacin (Cipro 500 mg, Schering Plough, Kenilworth, NJ, USA) and metronidazole (Flagyl 500 mg, Sanofi-Aventis, Tours, France), Group 2: Bioactive glass powders (BAG S53P4) of 60 mol% SiO2, 12 mol% P2O5 and 28 mol% CaO composition were prepared through sol gel processing route, all reagents were purchased from Sigma-Aldrich(Dorset, UK). Group 3: Non-setting Calcium hydroxide (CH) (Merk, Germany) was used, and finally, Group 4(Control): where no ICM was applied. Samples were kept in saline solution for either 2, 4, and 12 weeks, randomly selected samples from each group n=14 at each interval where intracanal medication removed, half of them n=7 were subjected to dentin Vickers microhardness test, in remaining half n=7 MTA (ProRoot, Dentsply Tulsa Dental, Tulsa, OK) placed 4 mm deep into the coronal third of the roots having a 4 mm-long chamber, samples were stored for a week at 37 °C at 100 % humidity to allow the complete setting of MTA, then push-out test was used to measure the dislocation resistance DR of MTA. Collected data were analyzed using a two-way ANOVA followed by Bonferroni’s post-hoc test was used for pair-wise comparisons (P ≤ 0.05). Results: showed that both DAP, CH groups of intracanal medication and time interval had a significant decreasing effect on dentine microhardness and MTA dislocation resistance the DR of MTA (P-value <0.001). While, BAG group`s results revealed significant increase in dentine microhardness and MTA dislocation resistance (P-value <0.001). The time factor displayed a significant effect on dentin microhardness and the DR of MTA (P-value <0.001).Conclusion: Regarding situations in this study, intracanal medications type and duration of application used in root canals disinfection through RET must be carefully chosen to avoid negative effect on dentin microhardness or DR of MTA jeopardizing the success of the treatment. BAG (S53P4) showed promising results, further studies needed to complete investigations about it as intracanal medication in RET.

Endodontic Management of a Tooth with Severe External Root Resorption using Injected Non-setting Calcium Hydroxide Paste: A Case Report

External Root Resorption (ERR) is a pathological condition that can lead to tooth loss if not diagnosed and treated correctly. Calcium Hydroxide Ca(OH)2 is an intracanal medicament, which is used in cases of teeth with pulp necrosis, peri-radicular lesions and ERR. This paper describes the endodontic management of a tooth with severe ERR using injected non-setting Ca(OH)2 paste. A 28-year-old patient was referred for endodontic evaluation of tooth 47, which presented an extensive composite resin restoration and was negative to cold test. Panoramic and periapical radiographs revealed the presence of a filled pulp chamber, calcified root canals, ERR on the mesial and distal roots, and apical periodontitis in the mesial and distal roots. The diagnosis of asymptomatic apical periodontitis and severe ERR was established, and conventional root canal treatment combined with non-setting Ca(OH)2dressing was chosen. After five months, no more discharge from the root canal was observed, and a decrease in the size of the periapical lesion and arrest of ERR was detected. The root canal was filled, and the patient was referred for restoration. At the 6-months follow-up, radiographic examination evidenced periapical repair and containment of the ERR process. Chemomechanical root preparation in association with a non-setting Ca(OH)2 dressing protocol allows positive outcomes during the management of severe ERR associated with pulp necrosis and periapical inflammation.

Comparison of the radiopacity of selected materials used for vital pulp therapy: An in vitro assessment.

An assessment of the therapeutic effects of vital pulp treatment is based on both clinical and radiological evaluation. The aim of the research was a long-term (after 1, 2, 4, 6, and 8 weeks) radiological assessment of X-ray absorption by 8 selected materials used for the vital treatment of dental pulp. The materials, prepared in accordance with the manufacturers' recommendations, were placed in molds measuring 10 mm in diameter and 2 mm in thickness. The molds with the samples were placed on an occlusal film with an aluminum step wedge, and then X-rayed using an intraoral X-ray unit. After processing, an X-ray image with varying degrees of opacity was obtained. The radiological density of the samples, the step wedge and the background was measured 6 times using a densitometer. The tests were repeated at the following intervals: after 7 days, and after 2, 4, 6, and 8 weeks. The molds with the material samples were stored in an incubator at 37°C and 95% humidity. The obtained results were statistically analyzed. The mineral trioxide aggregate (MTA) materials exhibited the highest degree of contrast, whereas the lowest radiopacity was shown for the non-setting calcium hydroxide preparations (p < 0.0001). Calcium hydroxide cements presented medium radiopacity values. The radiopacity of all the evaluated materials showed a statistically insignificant increasing tendency with regard to the duration of the experiment. All the tested preparations showed acceptable radiopacity, enabling radiological detection in the course of vital pulp therapy.

Dentists’ Knowledge, Attitude and Practice of Root Canal Treatment Procedure: Survey-based Research

The aim of this survey was to assess the dentists' knowledge, attitude and practice of endodontic treatment procedures and materials in Damascus city (capital of Syria), and the effect of endodontic specialty and years of experience on the survey findings. Two hundred direct contacts (25 multiple-choice questions containing) questionnaires were distributed to randomly selected dentists practicing in Damascus city in 11 different areas, and a questionnaire contained questions regarding dentists' knowledge, attitude, and practice of root canal treatment procedure. The collected data were entered into a personal computer and analyzed using the statistical package for the social sciences (SPSS), 25 edition. One hundred eighty-eight questionnaires were collected with a 94% response rate. About 71.8% were general dental practitioners (GDPs), 25.5% were not practicing molar endodontics, and only 5.3% were referring difficult cases to endodontists. 32.4% and 21.8% of respondents were practicing vital and necrotic single visit root canal treatment, respectively. Only 6.9% were using rubber dam isolation, and more than half of the respondents used the standardized preparation technique. Non-setting calcium hydroxide was used 100% as an intra-canal medicament during necrotic root canal treatment sessions.96.3% of our respondents prefer delaying final restoration to next visit for symptoms disappearance. It was evident that more practicing experience does not improve treatment options selections of endodontic treatment. So the continuous educational programs are a very important way to change the old or wrong concepts in dental offices. The sample covered a large number of dentists who are working in Damascus; the most developed place in Syria. It is also considered that for carrying out such kind of surveys as long as the dentists are familiar with this type of studies.

Assessment of root dentin pH changes in primary and permanent molars with different types of calcium hydroxide intracanal medication

PurposeTo evaluate root dentin pH changes using different calcium hydroxide medications in primary and permanent molar root canals. MethodsSixty primary and 60 permanent molar roots were prepared with Twisted files and assigned in two subgroups: Group1, nonsetting calcium hydroxide (n = 30); group 2, viscous vehicle-based material (ApexCal®) (n = 30). The assigned materials were delivered in root canals and then stored for 24 h, 7 days and 14 days. All specimens were transversely cut in three sections and pH change was determined by Expandable Ion Analyzer cooperating with Flat Membrane pH Electrode and Reference Half-Cell Electrode at sample root surfaces. Two-way ANOVA was used for statistical analysis. ResultsNo significant difference was observed in primary teeth at all test periods. The mean pH values of the nonsetting calcium hydroxide group (pH10.39–10.90) were greater than those in viscous vehicle-based group (pH 9.84–10.12), but significant difference was observed only at 24 h. Among permanent teeth, the highest pH values of both materials were observed at 7 days. The pH values of the nonsetting calcium hydroxide group (pH 10.40–11.10) were greater than those in the viscous vehicle-based group (pH 9.80–10.41); however, no significant difference was observed at any test period. ConclusionThe peak pH of nonsetting calcium hydroxide group was at 24 h in primary teeth and 7 days in permanent teeth. The nonsetting calcium hydroxide group showed higher pH values than those in the viscous group in both primary and permanent teeth.

Direct pulp capping in permanent teeth in children – types of pulp exposure, therapeutic indications. Part I

Direct pulp capping, as a method allowing the preservation of viable and healthy pulp, is a key element in the treatment of immature permanent teeth. Maintaining pulp vitality is a condition for continuous root development, which is important for long-term maintenance of the tooth in the oral cavity. Therefore, the maintenance of vital pulp should be one of the main goals in the treatment of young permanent teeth and biological treatment is particularly recommended in such cases. Since young pulp has a great regenerative potential, the success rates of direct pulp capping are high. Therapeutic indications for this method include traumatic and mechanical exposure of either healthy or reversibly inflamed pulp. Accurate assessment of the clinical condition of the tooth is crucial for the choice of the most appropriate treatment option. Another crucial issue is proper understanding of the mechanisms that occur in the pulp as a result of treatment. Choice of a therapeutic agent, such as commonly used non-setting calcium hydroxide or MTA is also essential. However, other, less popular preparations should be also considered.

Evaluation of cytotoxicity and pH changes generated by various dental pulp capping materials - an in vitro study.

Various materials are used in direct dental pulp capping method. Their biocompatibility and alkalizing abilities are of primary importance affecting therapeutic effects. The aim of this study was to evaluate and compare the cytotoxicity of various pulp-capping materials on human gingival fibroblasts and investigate the pH changes induced by these materials. Human gingival fibroblasts were cultured with nine direct pulp materials using culture plate inserts. The cytotoxic effects were recorded by using an MTT-based colorimetric assay after 3 and 24 h. In the second part of the experiment, the materials were inserted in dialysis tubes and transferred into plastic vials containing deionized water. The changes of the medium pH were measured after 3 and 24 h. We showed differences in cell viability of gingival fibroblasts after varied time of exposition for the tested materials. Cell viability after 24 h increased for Dycal, Biopulp, and Calcipro, and decreased for Calcipulpe, Angelus, Angelus White, and ProRoot Regular. Cell viability for ProRoot and Life did not change. Non-setting calcium hydroxide preparations followed by the MTA group and setting calcium hydroxide materials produced the highest pH. All the tested materials significantly increased pH (p < 0.0001) at 24 h. Currently used pulp capping materials varied in their cytotoxicity relative to human gingival fibroblasts and their alkalizing capacities. Since most likely pH does not affect the viability of cultured cells, further investigations are required to determine physicochemical properties of these materials and the biological activity of the dental pulp.

Margin Integrity and Secondary Caries of Lined or Non-lined Composite and Glass Hybrid Restorations After Selective Excavation In Vitro.

For deep carious lesions, selective carious tissue removal (leaving soft dentin close to the pulp) is suggested. Afterward, different restoration materials, such as resin composites or glass hybrids (GHs), can be placed. Many dentists also apply setting or non-setting calcium hydroxide liners before restoration. We compared margin integrity and susceptibility for secondary caries in differently restored premolars in vitro. In 48 extracted human premolars, artificial residual lesions were induced on pulpo-axial walls of standardized cavities. Teeth were restored using a GH (Equia Forte) or adhesively placed resin composite restoration (OptiBond FL and Tetric EvoCeram) without any liner (RC), resin composite restoration with a non-setting calcium hydroxide liner (RC_NCH), or resin composite restoration with a setting calcium hydroxide liner (RC_SCH). After thermomechanical cycling, groups (n=12) were compared regarding their gingivocervical margin integrity (proportion of irregularities, microgaps, gaps >5 μm, overhangs). Teeth were then submitted to a continuous culture Lactobacillus rhamnosus biofilm model. After 14 days, bacterial numbers in biofilms, along tooth-restoration margins and mineral loss (ΔZ) of secondary lesions, were determined. GH and RC_NCH showed significantly higher proportions of irregularities than RC and RC_SCH (p<0.05/Mann-Whitney). GH also showed significantly more gaps than alternative restorations (p<0.05). Bacterial numbers and ΔZ did not differ significantly between groups (p>0.05). GH and composites lined with non-setting calcium hydroxide showed reduced margin integrity compared with non-lined composites or composites lined with setting calcium hydroxide. This did not increase susceptibility for secondary caries.

Glass hybrid, but not calcium hydroxide, remineralized artificial residual caries lesions in vitro.

For deep carious lesions, less invasive carious tissue removal is recommended. The resulting residual carious lesions might benefit from remineralization by lining or restoration materials. We aimed to compare mineral gains in artificial residual lesions provided by calcium hydroxide and glass hybrid materials in combination with pulpal fluid simulation. On the coronal aspect of human dentin discs (n=20), artificial carious lesions were induced using acetic acid. Median mineral loss ΔZ [25th/75th percentiles] of resulting lesions was 1643 [1301/1858] vol%μm. One third of each disc served as baseline sample. The remaining disc was divided into four groups, each being covered with one experimental material (n=20/group): flowable composite (control (CO)), setting or non-setting calcium hydroxide liner plus flowable composite (CH-S, CH-NS), and glass hybrid (GH). Samples were mounted in a dual-chamber device. Pulpal surfaces were exposed to simulated pulpal fluid at 2.94kPa. Coronal surfaces were exposed to artificial saliva and rinsed with 200ppm NaF every 2weeks. After 12weeks, mineral loss differences (ΔΔZ) were assessed using transverse microradiography. Electron probe microscopic analysis was used to measure fluoride and strontium concentrations. Mineral gains were not significantly different between CO (ΔΔZ=372 [115/501] vol%μm), CH-S (ΔΔZ=317 [229/919] vol%μm), or CH-NS (ΔΔZ=292 [130/579] vol%μm; p>0.05/Wilcoxon test) but significantly increased in GH (ΔΔZ=1044 [751/1264] vol%μm, p<0.001). Samples in GH showed fluoride and strontium enrichment deep into the dentin. Such enrichment was not found in CO. Within the limitations of this study, GH, but not calcium hydroxide, provided coronal remineralization of residual carious lesions. Glass hybrids might provide additional remineralization of residual carious lesions. The functional implications of this mineral gain need to be evaluated.

Accidental periapical extrusion of non-setting calcium hydroxide: Unusual bone response and management

Premixed non-setting calcium hydroxide is frequently used as interim root canal dressing in endodontically involved permanent teeth and as obturating paste in deciduous teeth in pediatric dentistry. Wide apex in both cases makes it more prone for deliberate extrusion especially when applied with pressure delivery systems. Contrary to common belief the mix was not resorbed in two years with the complaint of insufficiency in mastication. Large mass of calcium hydroxide in bone delayed healing process even after its removal. The present case report intends to demonstrate unusual behavior of bone in response to oily non-setting preparation of calcium hydroxide. Therefore its application with pressure syringe should be reconsidered in pediatric dentistry.

Nerve lesions following apical extrusion of non-setting calcium hydroxide: A systematic case review and report of two cases

We present two cases of apical extrusion of non-setting, calcium hydroxide paste which had been placed as an interappointment root canal dressing during routine endodontic treatment resulting in tissue necrosis of a large part of the mandible. Surgical intervention consisted of resections in both instances.In relation to the cases presented, a systematic review of similar cases in the literature between 1980 and April 2013 was conducted which resulted in eight cases meeting the criteria outlined. As with the two presented cases, half of these eight cases showed serious adverse effects and the use of an injectable system had most often been related to apical extrusion. Consequently, great care should be taken when applying the paste into the canal system.

The effect of nonsetting calcium hydroxide on root fracture and mechanical properties of radicular dentine: a systematic review

The aim of this review was to identify and analyse all studies related to the effect of nonsetting calcium hydroxide [Ca(OH)(2)] on root fracture and various mechanical properties of radicular dentine. A PubMed search was conducted using the keywords 'calcium hydroxide' and 'dentistry' combined with MeSH terms 'tooth fractures' or 'mechanical phenomena' or 'compressive strength'. The search was expanded by including Embase and Web of Science databases, using the keywords 'calcium hydroxide' and 'root' and 'fracture'. The search was supplemented by checking the reference lists from each selected article. Each study had to meet the following criteria to be selected for review: (i) Inclusion of at least one experimental group with root or radicular dentine either filled with or exposed to nonsetting Ca(OH)(2); (ii) inclusion of at least one appropriate control group; and (iii) a minimum of five samples per experimental group. Only articles written in English were included. Of the 16 studies selected initially, 12 in vitro studies fulfilled the selection criteria for inclusion in the final review. No clinical studies that directly supported the correlation between Ca(OH)(2) intracanal dressing and root fracture were found in the literature. However, the majority of in vitro studies showed reduction in the mechanical properties of radicular dentine after exposure to Ca(OH)(2) for 5 weeks or longer. Conversely, the data were inconclusive regarding whether Ca(OH)(2) exposure for 1 month or less had a negative effect on the mechanical properties of radicular dentine.