Bioactive Bismuth Compounds: Is Their Toxicity a Barrier to Therapeutic Use?

Bismuth compounds are considered relatively non-toxic, with their low solubility in aqueous solutions (e.g., biological fluids) being the major contributing factor to this property. Bismuth derivatives are widely used for the treatment of peptic ulcers, functional dyspepsia, and chronic gastritis. Moreover, the properties of bismuth compounds have also been extensively explored in two main fields of action: antimicrobial and anticancer. Despite the clinical interest of bismuth-based drugs, several side effects have also been reported. In fact, excessive acute ingestion of bismuth, or abuse for an extended period of time, can lead to toxicity. However, evidence has demonstrated that the discontinuation of these compounds usually reverses their toxic effects. Notwithstanding, the continuously growing use of bismuth products suggests that it is indeed part of our environment and our daily lives, which urges a more in-depth review and investigation into its possible undesired activities. Therefore, this review aims to update the pharmaco-toxicological properties of bismuth compounds. A special focus will be given to in vitro, in vivo, and clinical studies exploring their toxicity.

Microstructural Evaluation of the Mineralized Apical Barrier Induced by a Calcium Hydroxide Paste Containing Iodoform: A Case Report.

INTRODUCTION: A 65-year-old man had nonsurgical retreatment using an iodoform and calcium hydroxide paste in a maxillary left canine with persistent apical periodontitis. An apical mineralized barrier (AMB) was observed 3-months postoperatively. Unfortunately, the tooth was extracted due to a cementum tear. This provided an opportunity to analyze the AMB histologically, as there is a lack of previous reports on its microstructure. METHODS: After extraction and removal of the granulation tissue from the root surface, the canine was processed, and observed using micro-computed tomography (µCT) and light microscopy. Thereafter, the specimen was resin-embedded specimen was evaluated by scanning electron microscopy, micro-X-ray fluorescence spectroscopy and Raman spectroscopy to understand the mechanism and nature of the AMB formation during apical healing. RESULTS: Nonsurgical retreatment was clinically successful based on the absence of clinical symptoms of apical periodontitis and the radiographic presence of an AMB. The AMB was opaque and could be readily differentiated from dentin under a light microscope. Micro-computed tomography analysis revealed that the AMB had the same mineral density as dentin. Scanning electron microscopy revealed that the AMB had two distinct layers based on the size of the calcified particles. Elemental mapping using micro-X-ray fluorescence spectroscopy showed that the localization of calcium and phosphorus differed between AMB and other areas of biomineralization. Raman spectral mapping revealed that the surface layer of the AMB consisted of collagen, calcium carbonate, and hydroxyapatite. CONCLUSIONS: This study explored new analytical methods for elucidating the apical wound-healing process and the nature of the mineralized repair. The findings provided detailed information on the AMB highlighting a bilaminar structure with high calcium components higher on the inside and a brightness similar to cementum not dentin and the presence of hydroxyapatite.

Biocompatibility, Biomineralization and Induction of Collagen Maturation with the Use of Calcium Hydroxide and Iodoform Intracanal Dressing.

Biocompatibility and biomineralization of root canal dressings are important requirements for periapical healing. This study evaluated the inflammatory response, biomineralization and tissue repair by collagen fiber maturation in the subcutaneous tissue of rats. Eighteen Wistar rats (n = 6) received subcutaneous implants: calcium hydroxide + propylene glycol [CH+P], calcium hydroxide + propylene glycol + iodoform [CH+P+I], iodoform + carbowax [I+Cwax] and carbowax [Cwax]. Extra empty tubes were used as a control [C]. After 7, 15 and 30 days, the implants were removed with surrounding tissue for staining of hematoxylin-eosin, Von Kossa, picrosirius red and without staining for analysis under polarized light. Results were analyzed via Kruskal-Wallis followed by Dunn testing for nonparametric data and ANOVA followed by a Tukey post hoc test for parametric data (p < 5%). At 7 days, all groups showed a moderate inflammatory reaction and thick fibrous capsule, except the [Cwax] group, with a severe inflammatory infiltrate (p < 0.05). After 15 days, all groups but control had a decrease in inflammatory response. At 30 days, all groups presented a mild reaction and thin fibrous capsule (p > 0.05). Only groups containing calcium hydroxide were found to be positive using Von Kossa staining and polarized light in all periods. At 7 days, all groups showed a higher proportion of immature fibers. At 15 days, the [CH+P] and [Cwax] groups increased their proportion of mature/immature fibers. At 30 days, only the [CH+P] group presented a significant prevalence of mature collagen fibers (p < 0.05). All groups showed biocompatibility, but only groups containing calcium hydroxide induced biomineralization. The addition of iodoform delayed tissue healing.

Massive Infected Dentigerous Cyst in a Young Child.

Dentigerous cysts are odontogenic cysts that form on the crown of an unerupted or partially erupted tooth. They are specifically anchored to the cementoenamel junction. Dentigerous cysts are known to rarely involve impacted deciduous teeth. Because of this rarity, this article reports a unique case of a five-year-old female patient who developed a dentigerous cyst in relation to a developing permanent left mandibular first molar tooth with its surgical treatment and histopathological features.

Role of iodoform in jaw lesions: a systematic review.

Iodoform formulations are used as packing material following the surgical removal of jaw lesions. The purpose of this review was to explore the evidence and efficacy of iodoform-based dressings. We have systematically reviewed published articles according to the PRISMA statement. The search was conducted in PubMed, Google Scholar, Semantic Scholar, and the Cochrane Library database for articles mentioning the use of iodoform as dressing material for jaw lesions from January 2000 to March 2022. Finally, 92 studies were included. A total of 386 patients whose ages ranged from five months to 86 years (male n = 180, female n = 117). Different formulations of iodoform used were BIPP (n = 67), Whitehead's varnish (n = 17), iodoform (n = 7) and, iodine (n = 1) for its antiseptic properties. An iodoform impregnated gauze pack was changed once a week, most commonly, for a stipulated duration, until complete healing of the cavity. In the present review, iodoform was used, most commonly, in pathological cavities following surgical treatment of ameloblastoma and odontogenic keratocyst. Toxicity was reported in two studies. Based on the current review, iodoform is relatively safe and can be used in the management of extensive jaw lesions in which secondary healing is expected. Prospective and randomised control trials are recommended to assess the efficacy of various formulations and to delineate the timeframe for patient compliance.

Physicochemical, Pre-Clinical, and Biological Evaluation of Viscosity Optimized Sodium Iodide-Incorporated Paste.

This study aimed to investigate the impact of different viscosities of silicone oil on the physicochemical, pre-clinical usability, and biological properties of a sodium iodide paste. Six different paste groups were created by mixing therapeutic molecules, sodium iodide (D30) and iodoform (I30), with calcium hydroxide and one of the three different viscosities of silicone oil (high (H), medium (M), and low (L)). The study evaluated the performance of these groups, including I30H, I30M, I30L, D30H, D30M, and D30L, using multiple parameters such as flow, film thickness, pH, viscosity, and injectability, with statistical analysis (p < 0.05). Remarkably, the D30L group demonstrated superior outcomes compared to the conventional iodoform counterpart, including a significant reduction in osteoclast formation, as examined through TRAP, c-FOS, NFATc1, and Cathepsin K (p < 0.05). Additionally, mRNA sequencing showed that the I30L group exhibited increased expression of inflammatory genes with upregulated cytokines compared to the D30L group. These findings suggest that the optimized viscosity of the sodium iodide paste (D30L) may lead to clinically favorable outcomes, such as slower root resorption, when used in primary teeth. Overall, the results of this study suggest that the D30L group shows the most satisfactory outcomes, which may be a promising root-filling material that could replace conventional iodoform-based pastes.

The efficacy of minocycline hydrochloride ointment versus iodoform gauze for alveolar osteitis: A prospective cohort study.

BACKGROUND: Alveolar osteitis (AO) is one of the most commonly encountered complication following tooth extraction, however, to date there is no standard methods of prevention and treatment. The study aims to investigate the efficiency of minocycline hydrochloride ointment (MHO) for the treatment of alveolar osteitis compared with traditional treatment with iodoform gauze (IG). METHODS/DESIGN: STROBE checklist was followed to report this study. All patients underwent tooth extraction either in our department or other hospitals, whom presented with postoperative pain, were screened out to meet the inclusion and exclusion criteria of this study about AO. Patients who fulfilled the inclusion criteria were enrolled in our prospective cohort study, and MHO or IG was administered. The Visual analog scale scores were used to assess the pain score of patients. The healing status of the extraction sockets was followed up. Differences in responses between groups were analyzed using Mann-Whitney U tests. Chi-square test was performed to explore the differences in the teeth position of AO. RESULTS: Of 41,371 patients underwent tooth extraction with post-operative follow-up in our departments, only 20 patients (0.05%) suffered from AO. 31 patients with AO, whose teeth were extracted in other places, were also enrolled. The incidence of AO was significantly higher in third molars than other teeth (P < 0.01). In 28 patients that were treated with MHO, the pain was relieved substantially on day 3 and almost painless on day 7. And only 25% of cases required dressing change more than once. Whilst 23 patients treated with IG, the pain was relieved on day 5, and 56.5% of cases required multiple dressing change. The difference between the two groups of VAS scores had statistical significance during treatment at 8 h, 24 h, 3d, 5d, and 7d. No allergic reaction or further infection occurred. CONCLUSION: MHO has a safer and higher therapeutic effect in the treatment of AO compared with traditional treatment with IG. MHO may become a preferred treatment modality for AO.

Physicochemical and Antibacterial Properties of Conventional and Two Premixed Root Canal Filling Materials in Primary Teeth.

In this study, some physicochemical and antibacterial properties of three root canal filling materials for primary teeth, Calplus "CP" (Prevest DenPro, Lewes, DE, USA), Bio-C Pulpecto "Bio-CP" (Angelus, Basil, Londrina, Paraná, Brazil), and Zinc Oxide and Eugenol "ZOE" (Prevest DenPro, Lewes, DE, USA) were compared. For each material, the pH, solubility, contact angle, and crystalline microstructure under SEM were evaluated. Their antibacterial activity against Enterococcus faecalis was determined through direct tests. The Kruskal−Wallis test was used to analyze the results using a one-way analysis of variance on ranks. All the materials had an alkaline pH at 3, 24, and 72 h, with CalPlus having the highest (p < 0.05). Bio-CP was more soluble during the evaluation period (24 h) than ZOE and CalPlus (p < 0.05). Bio-CP and ZOE demonstrated the creation of crystallite structures on their surfaces after immersion in PBS at 37 °C, whereas CalPlus showed none. The lowest contact angle was observed for Bio-CP (53 ± 1.5°); contact angles of (86 ± 4°) and (96 ± 1°), respectively, were observed after 10 s of the deposition of the water drop for CalPlus and ZOE. In conclusion, according to this study, there is still a need to develop new filling materials for primary teeth. ZOE, CalPlus and Bio-CP demonstrated different physicochemical and antibacterial properties, but none of the materials had optimal properties and could be considered the most suitable filling material for primary teeth pulpectomy. Bioceramics in their current state are not an alternative. The physicochemical and antibacterial properties still need improvement to fit the intricate anatomy of primary teeth.

Improvement of Biological Effects of Root-Filling Materials for Primary Teeth by Incorporating Sodium Iodide.

Therapeutic iodoform (CHI3) is commonly used as a root-filling material for primary teeth; however, the side effects of iodoform-containing materials, including early root resorption, have been reported. To overcome this problem, a water-soluble iodide (NaI)-incorporated root-filling material was developed. Calcium hydroxide, silicone oil, and NaI were incorporated in different weight proportions (30:30:X), and the resulting material was denoted DX (D5~D30), indicating the NaI content. As a control, iodoform instead of NaI was incorporated at a ratio of 30:30:30, and the material was denoted I30. The physicochemical (flow, film thickness, radiopacity, viscosity, water absorption, solubility, and ion releases) and biological (cytotoxicity, TRAP, ARS, and analysis of osteoclastic markers) properties were determined. The amount of iodine, sodium, and calcium ion releases and the pH were higher in D30 than I30, and the highest level of unknown extracted molecules was detected in I30. In the cell viability test, all groups except 100% D30 showed no cytotoxicity. In the 50% nontoxic extract, D30 showed decreased osteoclast formation compared with I30. In summary, NaI-incorporated materials showed adequate physicochemical properties and low osteoclast formation compared to their iodoform-counterpart. Thus, NaI-incorporated materials may be used as a substitute for iodoform-counterparts in root-filling materials after further (pre)clinical investigation.

Radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste: a retrospective study.

OBJECTIVE: To assess the radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste. MATERIALS AND METHODS: Clinical and radiographic data were collected from 115 necrotic immature permanent teeth (71 caused by trauma and 44 caused by dens evaginatus) treated with apexification using a modified calcium hydroxide. Postoperative root morphology and changes in radiographic root area (RRA) on periapical radiographs were determined and statistically evaluated. Regression analysis was performed to identify factors associated with the outcomes of apexification. RESULTS: The average time for a calcified barrier formation was 10.66 ± 6.37 months. The root morphology after apexification with calcium hydroxide + iodoform paste was similar to that previously described after calcium hydroxide apexification. Compared with the trauma cases, the dens evaginatus cases revealed more type I (40.91% vs 16.9%) and less type II morphology (45.45% vs 67.61%). Although the changes in RRA were limited, the dens evaginatus cases showed greater increment of RRA than the trauma cases (4.12% ± 5.58% vs 0.70% ± 5.21%, P < 0.001). A significant association was found between the preoperative stage of root development and postoperative percentage change in RRA (P < 0.001). CONCLUSIONS: Teeth caused by dens evaginatus had better outcomes after apexification than teeth caused by trauma. Early stages of root development were associated with superior radiographic outcomes. CLINICAL RELEVANCE: Apexification provided reliable outcomes in the treatment of immature teeth with pulp necrosis and apical periodontitis, even though the root development is limited. Treatment decision should be made with comprehensive evaluation of prognostic factors.

Review of endoscopic myringoplasty success: comparisons of intra-operative graft material and post-operative packing in terms of graft failure rate.

BACKGROUND: Myringoplasty success rate is estimated to be between 60 and 90 per cent. Factors predicting success include the choice of graft and use of auditory canal packing. This study aimed to determine the intra-operative factors associated with endoscopic myringoplasty success. METHODS: A retrospective review of all endoscopic myringoplasty cases between January 2017 and January 2020 was undertaken. Data were collected on: patient demographics, tympanic membrane perforation size, intra-operative details, audiology and post-operative outcomes. RESULTS: There was no significant difference in graft success rates between cases using bismuth iodoform paraffin paste and Spongostan packing (86.7 per cent vs 84.9 per cent, respectively). Conchal cartilage graft had a higher success rate (100.0 per cent) compared with Biodesign grafting biomaterial (66.7 per cent), but was not superior to tragal cartilage (84.6 per cent) or temporalis fat or fascia (80.0 per cent). CONCLUSION: Spongostan packing is equivalent to bismuth iodoform paraffin paste in terms of endoscopic myringoplasty success rate. Although conchal cartilage graft had higher success rates, it was not statistically significantly different from tragal cartilage.

Efficacy of an iodoform-based filling material for pulpectomy of primary teeth: A 24-month non-inferiority randomized clinical trial.

AIM: The aim of this non-inferiority randomized clinical trial was to compare the efficacy of an iodoform-based paste (Guedes-Pinto -(GP)) as a filling material in pulpectomies of primary teeth, and a standard material composed by calcium hydroxide and iodoform (CaOH/Iodof paste; Vitapex® ). DESIGN: A total of 104 teeth from 61 children (3-8 years old) were randomly allocated to two groups according to filling materials. Children were followed up for 24 months. The primary endpoint was the treatment success rate evaluated through clinical and radiographic examinations at follow-up, and the secondary outcome was the analysis of the canal filling quality. Differences in the proportion of treatment success was calculated based on 95% confidence intervals (95% CI) and with the Miettinen and Nurminen method in the intention-to-treat population, considering a -20% of the non-inferiority limit. RESULTS: From 104 randomized teeth, 102 were followed up after 24 months (attrition rate of 1.9%). The success rate of teeth treated with the GP paste was 86.8% (95% CI: 69.9-94.9) and 78.4% (95% CI: 61.8-89.1) with the CaOH/Iodof paste. Consequently, a non-inferiority of the GP paste was observed when compared to the CaOH/Iodof paste (P < .001). CONCLUSION: The GP paste has a non-inferior success rate than the CaOH/Iodof paste used as filling material for pulpectomy in primary teeth.

Myoclonus From Intoxication by Bismuth Iodoform Paraffin Paste (BIPP) Nasopharyngeal Packing.

Bismuth iodoform paraffin paste (BIPP) gauze is widely used as an antiseptic wound packing in otolaryngology, head, and neck surgery. Uncommonly, BIPP can cause intoxication. Our report highlights an elderly patient who developed encephalopathy and overt myoclonus after nasopharyngectomy secondary to intoxication by the components of the BIPP gauze. The patient's impaired renal function, the amount of BIPP packing and the extensive nature of his wound likely predisposed him to BIPP toxicity. The myoclonus and delirium resolved promptly after removal of the BIPP packs. Clinicians should be aware of the clinical features of BIPP intoxication because of its common usage.

Calcium hydroxide/iodoform nanoparticles as an intracanal filling medication: synthesis, characterization, and in vitro study using a bovine primary tooth model.

The aims of this in vitro study were to synthesize, characterize, and evaluate the efficacy of a Calcium Hydroxide/Iodoform nanoparticles (CHIN) paste compared with Ultrapex as intracanal filling medication using an experimental model of bovine primary teeth. CH nanoparticle synthesis was performed via the simple hydrolysis technique of reacting calcium nitrate with sodium hydroxide. SEM-EDS and FT-IR analyses were used to characterize the obtained product. 30% of CH nanoparticles were combined with 40% of iodoform and 30% silicone oil to prepare an intracanal filling paste (CHIN). All endodontic procedures were performed on 34 uniradicular primary bovine teeth. Every root canal was instrumented with K files (up to #35) and obturated with the nanoparticle paste (experimental) or Ultrapex® (control). Three outcome variables were studied: penetration depth through the root dentinal tubules, Ca2+ ion release, and filling paste dissolution rate. The obtained data were analyzed by Student's t test. The X-ray diffraction pattern of CH nanoparticles showed characteristic peaks at CH, as confirmed by FT-IR analyses in which an intense signal was observed at 3643 cm-1, characteristic of CH. In the morphological characterization, CH particles could be detected at the nanosize scale. When applied as intracanal filling, the CHIN paste exhibited a higher level of penetration through the root dentin tubules. The global mean penetration measures were 500 µm for the experimental paste and 380 µm for the control paste (p < 0.05). The release of Ca2+ ions (up to the seventh day) and the dissolution rate were significantly higher in the experimental paste group than in the control group. No significant differences were observed between the groups regarding pH levels. The findings of this study suggest the potential suitability of CHI nanoparticles as an alternative intracanal filling medication for infected or devitalized primary teeth.

Pasta de hidróxido de calcio/yodoformo en pulpectomías de dientes deciduos: Reporte de caso con seguimiento de seis meses / Calcium hydroxide/iodoform paste in primary teeth pulpectomies: a case report with six-month follow-up

Resumen Introducción: Las pastas de obturación a base de hidróxido de calcio/yodoformo han demostrado buenos resultados en pulpectomías de dientes primarios. Objetivos: describir el desempeño de una pasta de hidróxido de calcio/yodoformo (Calplus®) mediante la evaluación clínica y radiográfica en pulpectomias durante 6 meses. Metodología: Un paciente de sexo masculino de 2 años de edad acudió a la Clínica Odontológica de la Universidad Científica del Sur, Lima-Perú. Durante la evaluación clínica se diagnosticó caries de infancia temprana. Tratamientos preventivos y restauradores fueron realizados. Las pulpectomias fueron obturadas con (Calplus®). Para evaluar el desempeño, las pulpectomías fueron acompañadas durante 1, 3 y 6 meses mediante exámenes clínicos y radiográficos examinando dolor, movilidad patológica, alteraciones de tejido blando, rarefacción ósea, y reabsorción radicular patológica. Al tercer mes de seguimiento solo se observó contorno gingival alterado. Conclusiones: La pasta a base de hidróxido de calcio/yodoformo (Calplus®) demostró buen desempeño en pulpectomías de dientes primarios considerando aspectos clínicos y radiográficos después de 6 meses de seguimiento.

Abstract Introduction*: Calcium hydroxide/iodoform is a root canal filling material that have shown good results in pulpectomies of primary teeth. Objective: Describe the performance of a calcium hydroxide/iodoform (Calplus®) root canal filling material considering clinical and radiographic outcomes after 6 months follow-up. Methods: A 2-year-old male patient attended the Dental Clinic of Universidad Científica del Sur, Lima-Perú. Oral clinical examination showed early childhood caries. Preventive and restoration treatments were carried out. Pulpectomies were performed with Calplus®. To evaluate pulpectomies performance it was examined clinical and radiographic outcomes: pain, pathological mobility, soft tissue disorders, bone rarefaction and pathological root resorption. The clinical and radiographic findings at 1, 3, and 6 months were assessed. After three months, it was only observed altered gingival contour. Conclusion: Calcium hydroxide/ iodoform (Calplus®) root canal filling material showed good success rate in primary teeth pulpectomies considering clinical and radiographic outcomes after 6 months follow-up.

Efficacy of Endoactivator, CanalBrush, and passive ultrasonic irrigation in the removal of calcium hydroxide paste with iodoform and p-chlorophenol from root canals.

AIMS: We evaluated and compared EndoActivator, CanalBrush, and passive ultrasonic irrigation (PUI) in the removal of calcium hydroxide and calcium hydroxide with iodoform and p-chlorophenol paste (Calcipast Forte) from artificial standardized grooves in the apical third of root canals. MATERIALS AND METHODS: A total of 34 mandibular premolars were prepared and then split longitudinally. A standardized groove was prepared in the apical part of both segments. The grooves were filled with either calcium hydroxide or Calcipast Forte, and the segments were reassembled. CanalBrush, EndoActivator, or PUI were used. The amount of remaining medicament was evaluated using a four-grade scoring system. RESULTS: None of the irrigation methods could completely remove the pastes from the grooves. More Calcipast Forte paste was detected compared with calcium hydroxide (P < 0.01). PUI was the least effective method in removing Calcipast Forte. CONCLUSIONS: It was more difficult to remove Calcipast Forte than a water-based calcium hydroxide paste.

A comparison of calcium hydroxide/iodoform paste and zinc oxide eugenol as root filling materials for pulpectomy in primary teeth: A systematic review and meta-analysis.

Zinc oxide eugenol (ZOE) has traditionally been used as a root filling material in primary teeth pulpectomy. Calcium hydroxide and iodoform (Ca(OH)2/iodoform) may have advantages as a root canal filling material to evaluate treatment success of Ca(OH)2/iodoform pulpectomy in primary teeth compared with ZOE based on clinical and radiographical criteria. All human clinical studies reporting clinical and radiographical outcomes of Ca(OH)2/iodoform compared with ZOE in primary teeth pulpectomy were identified in digital bibliographic databases. Two authors independently selected studies and extracted relevant study characteristics. Success of treatment was based on an accomplishment of specific clinical and radiographical criteria. Meta-analyses were performed to appraise study heterogeneity and aggregated statistics. Out of 5,000 articles identified in initial search, 15 articles met all inclusion criteria, while 10 were included in the meta-analyses. At 6- and 12-month follow-up, there were no statistically significant differences in the clinical and radiographical success rates of Ca(OH)2/iodoform and ZOE. However, ZOE was shown to have statistically significant higher success rates at ≥18-month follow-up. On the basis of the findings of this systematic review, we recommend that Ca(OH)2/iodoform be utilized for pulpectomy in primary teeth nearing exfoliation; conversely, ZOE should be utilized when exfoliation is not expected to occur soon. Future randomized control clinical trials with a long-term follow-up are needed before a reliable conclusion can be drawn as to the best pulpectomy material. The success of pulpectomy in primary teeth depends on selecting the ideal root canal filling material. It is challenging to select the appropriate filling materials for primary teeth. ZOE or ZOE/iodoform combined with Ca(OH)2 appears to be the materials of choice if primary teeth are not nearing exfoliation. More high-quality randomized control clinical trials with a long-term follow-up period are needed before a reliable conclusion can be drawn as to the best pulpectomy material in primary teeth (systematic review registration number: CRD42016037563).

Comparative Evaluation of Tissue Response of MTA and Portland Cement with Three Radiopacifying Agents: An Animal Study.

AIM: This study compared the tissue reaction of 80 wt% of White Portland cement (WPC) mixed with 20 wt% of three radiopacifying agents: Bismuth oxide/Iodoform/Zirconium oxide with MTA in rat subcutaneous connective tissue. MATERIALS AND METHODS: The study was performed in 18 albino rats by implanting the WPC mixed with radiopacifying agents loaded in a polyethylene tube. Empty tubes were used as a control. At the end of 7, 30 and 60 days excisional biopsy of the implant along with surrounding tissues was done and sent for histological examination. RESULTS: In the 7 days experimental period there was no significant difference between groups in terms of the tissue response. In 30 and 60 days period significant difference was seen between the control (empty tube) and the other groups. But there was no significant difference between WPC mixed with radiopacifiers BiO/Iodoform/ZrO2and MTA. CONCLUSION: The tissue reaction of the tested materials, White Portland cement (WPC) + Bismuth oxide, WPC + Iodoform, and WPC + Zirconium dioxide were similar to MTA (Pro Root MTA) in all experimental periods 7 days, 30 days and 60 days.

Application of different biomaterial capping agents in pulpotomy of deciduous molars / 实用口腔医学杂志

Objective: To investigate the effects of biomaterial capping agents mineral trioxide polymer (MTA), calcium hydroxide iodoform paste (CHI) and calcium hydroxide (CH), in the pulpectomy of deciduous molars. Methods: 96 children undewent deciduous molar pulpectomy were included and divided into MTA, CHI and CH groups (n = 32), MTA, CHI and CH were respectively usd as capping agents for the 3 groups. The patients were regularly examined clinically and by X-ray at 3, 6 and 12 months after surgery. Results: 3 months after treatment the total effective rate of MTA, CHI and CH groups was 100％, 96. 88％ and 96. 88％ respectively (P＞ 0. 05), 6 months after operation 90. 63％, 93. 75％ and 78. 13％ respectively (P＞ 0. 05), 12 months after operation. 87. 50％, 84. 38％ and 59. 38％ respectively (P ＜ 0. 05) . There was no significant difference in root resorption between the 3 groups at 3 months and 6 months after surgery (P＞ 0. 05) . 12 months after operation, the non-root resorption rate of MTA, CHI and CH group was 93.75％, 87. 50％ and 50. 00％ respectively (P ＜ 0. 05) . The mild root resorption rate of group MTA, CHI and CH was 3. 13％, 9. 38％and 21. 88％; the moderat resorption 3. 13％, 3. 13％ and 18. 75％; the severe resorption 0, 0 and 9. 38, respectively. Conclusion:MTA and CHI used as capping agents are effective in pulpotomy, CH is prone to root absorption, which leads to treatment failure.