Age estimation of fragmented human dental remains by secondary dentin virtual analysis.

Unlike bones, teeth are remarkably resilient and can withstand severe trauma, making age assessment based on the dentition essential for forensic analysis. Modern techniques for age estimation focus on pulp-chamber volume measurements using radiographs and computerized tomography (CT); however, these are applicable only for complete teeth (i.e., with intact crown and root). In the current study, we developed a new approach using high-resolution micro-computerized tomography (µCT) to visualize the secondary dentin (SD), an inner layer surrounding the pulp which accumulates with age, thus facilitating age estimation of fragmented and broken teeth.The growth pattern of the SD with age was analyzed for 77 lower premolars from two anthropological collections. A comparison of SD virtual segmentation and histological measurement was highly correlative (ICC = 0.95). SD was measured per volume (mm3) of a 1 mm thick slice directly below the cemento-enamel junction. Regression analysis using SD measurements increased the success rates of age estimation (82%) compared with the "gold-standard" pulp/dentin method (54%) in the range of ± 10 years. The accuracy of age estimation based on SD analysis was improved to a range of 7-8 years.The SD method thus allows age estimation with greater prediction rates and better accuracy based on only a small fragment of a tooth in a non-invasive manner. This novel methodology is easy to use, accessible, and bears implications in various fields such as forensic sciences and anthropological research.

Dissecting dentine-pulp injury and wound healing responses: consequences for regenerative endodontics.

A thorough understanding of the biology of the dentine-pulp complex is essential to underpin new treatment approaches and maximize clinical impact for regenerative endodontics and minimally invasive vital pulp treatment (VPT) strategies. Following traumatic and carious injury to dentine-pulp, a complex interplay between infection, inflammation and the host defence responses will occur, which is critical to tissue outcomes. Diagnostic procedures aim to inform treatment planning; however, these remain clinically subjective and have considerable limitations. As a consequence, significant effort has focussed on identification of diagnostic biomarkers, although these are also problematic due to difficulties in identifying appropriate diagnostic fluid sources and selecting reproducible biomarkers. This is further compounded by the link between inflammation and repair as many of the molecules involved exhibit significant multifunctionality. The tertiary dentine formed in response to dental injury has been purposefully termed reactionary and reparative dentine to enable focus on associated biological processes. Whilst reactionary dentine produced in response to milder injury is generated from surviving primary odontoblasts, reparative dentine, in response to more intense injury, requires the differentiation of new odontoblast-like cells derived from progenitor/stem cells recruited to the injury site. These two diverse processes result in very different outcomes in terms of the tertiary dentine produced and reflect the intensity rather than specific nature (nonexposure versus exposure) of the injury. The subsequent identification of the odontoblast-like cell phenotype remains challenging due to lack of unique molecular or morphological markers. Furthermore, the cells ultimately lining the newly deposited dentine provide only a snapshot of events. The specific source and plasticity of the progenitor cells giving rise to the odontoblast-like cell phenotype are also of significant debate. It is likely that improved characterization of tertiary dentine may better clarify the influence of cell derivation for odontoblast-like cells and their diversity. The field of regenerative endodontics offers exciting new treatment opportunities, and to maximize outcomes, we propose that the term regenerative endodontics should embrace the repair, replacement and regeneration of dentine-pulp.

Use of 0.4-Tesla static magnetic field to promote reparative dentine formation of dental pulp stem cells through activation of p38 MAPK signalling pathway.

AIM: To investigate whether static magnetic fields (SMFs) have a positive effect on the migration and dentinogenesis of dental pulp stem cells (DPSCs) to promote reparative dentine formation. METHODOLOGY: In vitro scratch assays and a traumatic pulp exposure model were performed to evaluate the effect of 0.4-Tesla (T) SMF on DPSC migration. The cytoskeletons of the DPSCs were identified by fluorescence immunostaining and compared with those of a sham-exposed group. Dentinogenic evaluation was performed by analysing the expressions of DMP-1 and DSPP marker genes using a quantitative real-time polymerase chain reaction (qRT-PCR) process. Furthermore, the formation of calcified deposits was examined by staining the dentinogenic DPSCs with Alizarin Red S dye. Finally, the role played by the p38 MAPK signalling pathway in the migration and dentinogenesis of DPSCs under 0.4-T SMF was investigated by incorporating p38 inhibitor (SB203580) into the in vitro DPSC experiments. The Student's t-test and the Kruskal-Wallis test followed by Dunn's post hoc test with a significance level of P < 0.05 were used for statistical analysis. RESULTS: The scratch assay results revealed that the application of 0.4-T SMF enhanced DPSCs migration towards the scratch wound (P < 0.05). The cytoskeletons of the SMF-treated DPSCs were found to be aligned perpendicular to the scratch wound. After 20 days of culture, the SMF-treated group had a greater number of out-grown cells than the sham-exposed group (nonmagnetized control). For the SMF-treated group, the DMP-1 (P < 0.05) and DSPP genes (P < 0.05), analysed by qRT-PCR, exhibited a higher expression. The distribution of calcified nodules was also found to be denser in the SMF-treated group when stained with Alizarin Red S dye (P < 0.05). Given the incorporation of p38 inhibitor SB203580 into the DPSCs, cell migration and dentinogenesis were suppressed. No difference was found between the SMF-treated and sham-exposed cells (P > 0.05). CONCLUSION: 0.4-T SMF enhanced DPSC migration and dentinogenesis through the activation of the p38 MAPK-related pathway.

Dental age estimation in the living after completion of third molar mineralization: new data for Gustafson's criteria.

There is a need for dental age estimation methods after completion of the third molar mineralization. Degenerative dental characteristics appear to be suitable for forensic age diagnostics beyond the 18th year of life. In 2012, Olze et al. investigated the criteria studied by Gustafson using orthopantomograms. The objective of this study was to prove the applicability and reliability of this method with a large cohort and a wide age range, including older individuals. For this purpose, 2346 orthopantomograms of 1167 female and 1179 male Germans aged 15 to 70 years were reviewed. The characteristics of secondary dentin formation, cementum apposition, periodontal recession and attrition were evaluated in all the mandibular premolars. The correlation of the individual characteristics with the chronological age was examined by means of a stepwise multiple regression analysis, in which the chronological age formed the dependent variable. Following those results, R 2 values amounted to 0.73 to 0.8; the standard error of estimate was 6.8 to 8.2 years. Fundamentally, the recommendation for conducting age estimations in the living by these methods can be shared. The values for the quality of the regression are, however, not precise enough for a reliable age estimation around regular retirement date ages. More precise regression formulae for the age group of 15 to 40 years of life are separately presented in this study. Further research should investigate the influence of ethnicity, dietary habits and modern health care on the degenerative characteristics in question.

Clinical and ultrastructural effects of different liners/restorative materials on deep carious dentin: a randomized clinical trial.

We evaluated the effect of calcium hydroxide cement (CHC) and glass ionomer cement (GIC) on carious dentin and bacterial infections after partial caries removal and sealing. Sixty permanent teeth with deep lesions underwent partial caries removal, the application of CHC, GIC or wax, i.e. negative control (NC), and were then sealed for 3-4 months. After the partial caries removal and the sealing period, the dentin was clinically assessed (colour and consistency) and analysed by scanning electron microscopy to assess dentin organization and bacterial infections. The effect of the treatment in each group was assessed by the Wilcoxon and χ2 tests, differences among groups by the Kruskal-Wallis test and the correlations between variables by Spearman correlation. No clinical symptoms or radiographic signals of pulpits or pulp necrosis were observed during the study. Dentin darkening was observed after the sealing period in the CHC and NC groups (p < 0.05). However, there was no difference in the colour after treatment among the 3 groups (p > 0.05). Dentin hardening occurred in all groups after treatment (p < 0.05), also with no differences (p > 0.05). Dentin samples showed better organization after the sealing period than after partial caries removal, with total or partial obliteration of dentinal tubules (CHC p < 0.03, GIC p < 0.05, NC p < 0.01) and a reduction of bacterial infections (CHC p < 0.03, GIC p < 0.05, NC p < 0.03). No differences were observed. Correlations between the different criteria, except for colour and bacterial infection, were detected in all cases. Partial caries removal and sealing resulted in dentin hardening, decreased bacterial numbers and dentin reorganization, irrespective of the dentin protection used.

Tertiary dentinogenesis with calcium hydroxide: a review of proposed mechanisms.

Calcium hydroxide has been used extensively in dentistry for a century. Despite its widespread use as a pulp-capping agent, its mechanisms of action still remain ambiguous. Understanding its modes of action will lead to a broader understanding of the mechanisms associated with induced dentinogenesis and help in optimizing the currently available agents to target specific regenerative processes to obtain the best possible clinical outcomes. A literature search relating to mechanisms of dentinogenesis of calcium hydroxide up to December 2011 was carried out using pubmed and MEDLINE database searches as well as manual searching of cross-references from identified studies. Resulting suggestions regarding dentinogenic mechanisms of calcium hydroxide range from direct irritating action of the material to induction of release of biologically active molecules. The purpose of this article is to discuss various mechanisms through which calcium hydroxide may induce tertiary dentinogenesis in the light of observations made in included studies.

Radiographic evaluation of Gustafson's criteria for the purpose of forensic age diagnostics.

The main criteria used in dental age estimation in living young individuals are mineralisation and eruption of the third molars. In order to further diversify the spectrum of characteristics after completion of third molar development, tests were undertaken to determine whether the characteristics studied by Gustafson can be ascertained with the required forensic certainty with the aid of the orthopantomogram and whether the evaluation of these could render forensic odontological age diagnoses possible beyond the 18th year of life. For this purpose, 1,299 conventionally produced orthopantomograms of 650 female and 649 male Germans aged from 15 to 40 years were studied. The characteristics of secondary dentin formation, cementum apposition, periodontal recession and attrition were evaluated in all the mandibular premolars. The correlation of the individual characteristics with chronological age was studied with the aid of a multiple regression analysis in which chronological age formed the dependent variable. Depending on the tooth studied, the R values amounted to 0.65 to 0.73; the standard error of estimate was 5.3 to 5.7 years. Basically, the regression equations calculated can be recommended for age estimation in living individuals, although it should be borne in mind that the applicability of the new method presented is limited by the quality of the X-ray images.

A feasibility study for the analysis of reparative dentinogenesis in pOBCol3.6GFPtpz transgenic mice.

AIM: To examine the feasibility of using the pOBCol3.6GFPtpz [3.6-green fluorescent protein (GFP)] transgenic mice as an in vivo model for studying the biological sequence of events during pulp healing and reparative dentinogenesis. METHODOLOGY: Pulp exposures were created in the first maxillary molar of 12-16-week-old 3.6-GFP transgenic mice with CD1 and C57/Bl6 genetic background. Direct pulp capping on exposed teeth was performed using mineral trioxide aggregate followed by restoration with a light-cured adhesive system (AS) and composite resin. In control teeth, the AS was placed in direct contact with the pulp. Animals were euthanized at various time points after pulp exposure and capping. The maxillary arch was isolated, fixed and processed for histological and epifluorescence analysis to examine reparative dentinogenesis. RESULTS: Analysis of teeth immediately after pulp exposure revealed absence of odontoblasts expressing 3.6-GFP at the injury site. Evidence of reparative dentinogenesis was apparent at 4 weeks in 3.6-GFP mice in CD1 background and at 8 weeks in 3.6-GFP mice with C57/Bl6 background. The reparative dentine with both groups contained newly formed atubular-mineralized tissue resembling a dentine bridge and/or osteodentine that was lined by cells expressing 3.6-GFP as well as 3.6-GFP expressing cells embedded within the atubular matrix. CONCLUSION: This study was conducted in a few animals and did not allow statistical analysis. The results revealed that the 3.6-GFP transgenic animals provide a unique model for direct analysis of cellular and molecular mechanisms of pulp repair and tertiary dentinogenesis in vivo. The study also shows the effects of the capping material and the genetic background of the mice in the sequence and timing of reparative dentinogenesis.

Evaluation of mineral trioxide aggregate (MTA) versus calcium hydroxide cement (Dycal(®) ) in the formation of a dentine bridge: a randomised controlled trial.

AIM: To assess the effectiveness of mineral trioxide aggregate (MTA) used as an indirect pulp-capping material in human molar and premolar teeth. METHODOLOGY: We conducted a clinical evaluation of 60 teeth, which underwent an indirect pulp-capping procedure with either MTA or calcium hydroxide cement (Dycal(®) ). Calcium hydroxide was compared with MTA and the thickness of the newly formed dentine was measured at regular time intervals. The follow-up was at 3 and 6 months, and dentine formation was monitored by radiological measurements on digitised images using Mesurim Pro(®) software. RESULTS: At 3 months, the clinical success rates of MTA and calcium hydroxide were 93% and 73%, respectively (P = 0.02). At 6 months, the success rate was 89.6% with MTA, and remained steady at 73% with calcium hydroxide (P = 0.63). The mean initial residual dentine thickness was 0.23 mm, and increased by 0.121 mm with MTA and by 0.136 mm with calcium hydroxide at 3 months. At 6 months, there was an increase of 0.235 mm with MTA and of 0.221 mm with calcium hydroxide. CONCLUSIONS: A higher success rate was observed in the MTA group relative to the Dycal(®) group after 3 months, which was statistically significant. After 6 months, no statistically significant difference was found in the dentine thickness between the two groups. Additional histological investigations are needed to support these findings.

Evaluation of dentin formed in autogenous tooth transplantation in the dog: a comparison between one- and two-stage surgical techniques.

This study was designed to compare the thickness of dentin formed associated with autogenous tooth transplantation in dogs, using either one- or two-stage surgical techniques. The study consisted of three Beagles, older than 5 months, in which six incisors and six premolars were transplanted to mechanically prepared recipient sockets. One group was transplanted using a one-stage method to recipient beds prepared immediately before transplantation. The second groups of teeth were transplanted using a two-stage method in which the recipient beds were prepared and left to heal for 7 days before transplantation. Dogs were injected with xylenol orange, calcein and oxytetracycline at 2 days before, 3 and 9 weeks after transplantation, respectively, for vital staining. Clinical examinations were carried out every week, and the animals were euthanized 9 weeks later. The jaws were resected, fixed in formaldehyde and embedded in resin. Undemineralized sections were cut and examined by fluorescent microscopy. The thickness of dentin formed in the third week after transplantation and 9 weeks was evaluated by undertaking histomorphometric analysis and analysed using the Mann-Whitney U test (P = 0.05). All the transplanted teeth in both groups survived, and the dentin was formed. No statistically significant difference was found in the thickness of dentin formed in the third week and formed in the third to ninth week between the treatment groups (P = 0.999 and P = 0.998, respectively). This study demonstrated that there was no difference between the two surgical techniques in terms of the thickness of dentin formed in transplanted teeth.

Clinical and radiographic outcomes of pulpotomized primary molars treated with white or gray mineral trioxide aggregate and ferric sulfate--long-term follow-up.

AIM: To compare the long-term clinical and radiographic outcomes of pulpotomies in primary molars performed with white or gray Mineral Trioxide Aggregate (MTA) in combination with ferric sulfate (FS), when one package of MTA is used for multiple treatments. DESIGN: Sixty eight children with 86 vital carious primary molars underwent pulpotomy with FS, and grey or white MTA. One package of MTA was used for 7-8 treatments. Clinical and radiographic evaluation was performed before and 6 to 47 months after treatment. RESULTS: Success rates were similar for pulpotomies performed with white (60-teeth) and grey MTA (16 teeth) (p > 0.05), and for those performed with the addition of FS to white or gray MTA when one package of MTA was used for multiple pulpotomies compared to one package of MTA alone. CONCLUSION: Gray and white MTA in conjunction with FS induce comparable clinical and radiographic success rate. The use of one package of MTA for multiple pulpotomies, combined with FS, is a cost-effective treatment.

Effect of glypican-1 gene on the pulp cells during the reparative dentine process.

GPC-1 (glypican-1) is a cell surface heparan sulfate proteoglycan that acts as a co-receptor for heparin-binding growth factors and members of the TGF-ß (transforming growth factor beta-1) family. The function of cell-surface proteoglycans in the reparative dentine process has been under investigation. Gpc-1 was detected with similar frequency as tgf-ß1 in the cDNA library using mRNA from the odontoblast-like cell-enriched pulp of rat incisors. The aim of this study was to test our hypothesis that gpc-1 may be related to reparative dentine formation. We examined the expression of this gene during the reparative dentine process, as well as the effect of gpc-1 on odontoblast-like cell differentiation using siRNA (small interfering RNA) to down-regulate gpc-1 expression. Immunohistological examination showed that GPC-1 was expressed in pulp cells entrapped by fibrodentine and odontoblast-like cells as well as TGF-ß1. The mRNAs for gpc-1, -3 and -4, except for gpc-2, were expressed during odontoblast-like cell differentiation in pulp cells. The relative levels of gpc-1 mRNA were increased prior to the differentiation stages and were decreased during the secretory and maturation stages of pulp cells. Down-regulation of gpc-1 expression resulted in a 3.9-fold increase in tgf-ß1 expression in pulp cells and a 0.3-fold decrease in dspp (dentine sialophosphoprotein) expression compared with control. These results suggested that gpc-1 and tgfß-1 expression are necessary for the onset of differentiation, but should be down-regulated before other molecules are implicated in the formation of reparative dentine. In conclusion, gpc-1 expression in odontoblast-like cells is associated with the early differentiation but not with the formation of reparative dentine.

A comparative study of dental pulp response to several pulpotomy agents.

AIM: To examine the in vivo response of dental pulps in dogs to three pulp-capping agents: calcium hydroxide (CH), mineral trioxide aggregate (MTA) and a new endodontic calcium enriched mixture (CEM) cement. METHODOLOGY: Thirty-six second and third premolar teeth in six beagle dogs were randomly assigned to three experimental groups; CH, MTA or CEM cement. Following isolation and exposure, pulp tissues were removed with a fissure bur and haemostasis achieved. The pulps were dressed with appropriate materials, and the access cavity restored with amalgam. Histological analysis was performed 8 weeks after treatment; the samples were assessed by an independent observer for calcified bridge formation, pulp vitality and pulp inflammation. The data were analysed by Kruskal-Wallis, Mann-Whitney and one-way anova tests. RESULTS: The number of root canals that showed calcified bridge formation, pulp vitality and lack of inflammation was significantly higher for teeth capped with either MTA or CEM cement in comparison with CH (P < 0.05). No significant difference was found between the CEM cement and MTA in terms of calcified bridge formation, pulp vitality and lack of inflammation (P > 0.05). CONCLUSIONS: Mineral trioxide aggregate and CEM cement were associated with a similar favourable biological response to pulpotomy treatment and demonstrated a more effective induction of dentinal bridge formation compared to CH.

Transdentinal stimulation of tertiary dentine formation and intratubular mineralization by growth factors.

AIM: To evaluate the effects of recombinant growth factors on tertiary dentine formation and intratubular mineralization after their application on deep dentinal cavities in dog's teeth. METHODOLOGY: Treatment included dentinal etching (37% phosphoric acid) and applications of bioactive molecules (1 microg mL(-1) TGF-beta1, 10 microg mL(-1) IGF-1, 10 microg mL(-1) bFGF, 10 microg mL(-1) OP-1 or 1 microg mL(-1) monoclonal anti-human TGF-beta1 in phosphate buffered saline, PBS) at the dentinal base of buccal Class V cavities. Control groups were treated with 0.1% dog serum albumin (DSA) in PBS omitting the growth factors. This was performed both with and without dentinal etching. The dentinal responses regarding tertiary dentine formation and intratubular mineralization were assessed after 3 and 8 weeks, respectively, using light and scanning electron microscopy. Some specimens were also subjected to dentine permeability testing. RESULTS: The group treated with transforming growth factor-beta1 (TGF-beta1) and, to a lesser extent, the one treated with osteogenic protein-1 (OP-1) showed significantly greater (P < 0.05) tertiary dentine formation and intratubular mineralization over an 8-week period when compared with the control and the other experimental groups. There were no significant differences between groups in reduction in dentine permeability after treatment. CONCLUSION: Treatment of exposed dentinal tubules with biologically active molecules might induce intratubular mineralization and tertiary dentine formation. Further research is needed to substantiate any clinical benefits as opposed to traditional treatments of exposed dentine so as to provide a scientific base for the clinical regulation of dentine reactions.

Three-dimensional observation of decrease in pulp cavity volume using micro-CT: age-related change.

We investigated three-dimensional decrease in the volume of the pulp chamber caused by age-related secondary dentin formation using micro-CT and evaluated the applicability of the results to evaluation of age taking into account sex, age and tooth type. Decrease was slightly higher in females than in males, and a higher correlation between decrease and aging was observed in females. A comparison between age-groups revealed that decrease progressed between the fifties and sixties in males, and the forties and fifties in females. A stronger correlation between aging and decrease was observed in the mandibular central incisors than in the mandibular second premolars. This correlation was higher than other correlations between sexes and age-groups.

Pulpal responses to bacterial contamination following dentin bridging beneath hard-setting calcium hydroxide and self-etching adhesive resin system.

To evaluate the pulp healing to bacterial contamination beneath a hard-setting calcium hydroxide (DY: Dycal, L.D. Caulk Co.) and a self-etching adhesive resin (2V: Clearfil Liner Bond 2V, Kuraray Medical Inc.) following dentin bridge formation. Class V cavities were prepared on 30 monkey teeth, and the pulps were exposed with a carbide bur through the cavity floor. Each exposed pulp was capped with either DY or 2V. The cavities were restored with a hybrid resin composite. The resin composite was removed at 180 days after capping, and then cavities were left open to the oral environment for 2 weeks to obtain bacteria contamination DY (BDY) and 2V (B2V; n = 10). A non-bacterial-contaminated group capped with DY was used as control. After bacterial challenges, inflammatory cell infiltration, incidence and differentiation of dentin bridges were evaluated histologically. There were significant differences in the presence of inflammatory cell infiltration among all groups (P < 0.05). No moderate or severe inflammatory reaction was found in Group DY. Group BDY showed moderate or severe inflammatory cell infiltration in 50%, and showed four necrotic specimens. Although no statistically significant difference was found in the formation and differentiation of dentin bridges among all groups, tunnel defects in dentin bridges were detected in 70% (DY), 80% (BDY), and 50% (B2V). Group B2V showed a significantly lower presence of inflammatory cell infiltration than Group BDY (P < 0.05). Bonding agent is supposed to seal the exposure site, and the remaining bonding agent on the cavities was effective as the barrier in the dentin bridges after bacterial challenges.

Effect of curing method of a dual-cure resin cement on monkey pulpal reaction after bonding of tooth-colored inlay.

To compare the pulpal responses to light-cured and self-cured resin cements, cervical cavities were prepared in monkey's teeth, followed by application of etching gel and adhesive (Single Bond). A dual-cure resin cement (RelyX ARC) was applied, and hybrid composite inlays (Estenia) were bonded to the cavities. In one group, the cavities were photoirradiated for 20 seconds and the resin cement light-cured. In the other group, the resin cement was self-cured for six minutes without any photoirradiation. After experimental periods of seven, 28, and 70 days, histological features of pulp tissue were evaluated and compared. Results showed no significant differences in the histological features of the pulp tissues between the two curing methods. Both light-cured and self-cured resin cements showed acceptable biological compatibility with the monkey pulp. No bacterial penetration along the cavity walls was detected with either curing method.

Dentine-pulp tissue engineering in miniature swine teeth by set calcium silicate containing bioactive molecules.

OBJECTIVE: The present study aims to investigate whether reparative dentinogenesis could be guided at central pulpal sites or at a distance from the amputated pulp of miniature pig teeth, by using set calcium silicate-based carriers containing human recombinant bioactive molecules. DESIGN: Pulp exposures were performed in 72 permanent teeth of 4 healthy miniature swine. The teeth were capped with pre-manufactured implants of set calcium silicate-based material containing BMP-7, TGFß1 or WnT-1, for 3 weeks. Conical-shaped intrapulpal implants were exposed in the central pulp core, while disc-shaped extrapulpal implants were placed at a distance from the amputated pulp. Implants without bioactive molecules were used as controls. Thickness and forms of new matrix mineralized deposition were assessed histologically at post-operative periods of 3 weeks by light microscopy. RESULTS: Intrapulpal applications: Calcified structures composed of osteodentine were found in contact with the BMP-7 implants. An inhomogeneous calcified tissue matrix was found around the WnT-1 carriers. A two-zone calcified structure composed of osteodentine and a thicker tubular matrix zone was seen at the TGFß1 carrier-pulp interface. Extrapulpal applications: The space between WnT-1 implants and pulp periphery had been invaded by soft tissue with traces of calcified foci. Thick calcified structures composed of osteodentine were found surrounding pulp exposure sites in response to application of BMP-7. Spindle-shaped cells associated with atubular calcified matrix or elongated polarized cells associated with tubular dentine-like matrix were found along the cut dentinal walls of the TGFß1 group. CONCLUSION: The present experiments indicated that set calcium silicate could be used as carrier for biologically active molecules. TGFß1 was shown to be an effective bioactive molecule in guiding tertiary dentine formation.

The incidence of pulp healing defects with direct capping materials.

PURPOSE: To (1) study the injury and healing activity of the pulp tissue to calcium hydroxide [Ca(OH)2], resin composite (RC) and resin-modified glass-ionomer (RMGI) materials when used as direct pulp capping agents, and (2) compare the incidence of healing defects between these materials. METHODS: 135 Class V pulp exposed cavities were prepared in non-human primate teeth. Direct pulp capping was conducted over 6 to 730 days with hard set Ca(OH)2, RMGI and CR materials. Healing defects recorded were: (1) bacterial leakage with McKays stain; (2) operative debris including dentin fragments and particles of capping material; (3) pulpal inflammatory activity according to FDI standards; (4) area and absence of dentin bridge formation; and (5) presence of tunnel defects in bridge. Statistical analysis was evaluated using ANOVA. RESULTS: The capping materials were associated with varying levels of pulp healing defects, including tunnel defects (P= 0.0001); operative debris (P= 0.0001); pulpal inflammatory cell activity (P= 0.0073) and bacterial leakage (P= 0.0260). Other healing defects, and the area of dentin bridge were not influenced by capping materials (P> 0.05).

Dentin bridge formation after white mineral trioxide aggregate (white MTA) pulpotomies in primary molars.

PURPOSE: To evaluate, clinically and radiographically, the dentin bridge formation potential of white mineral trioxide aggregate (white MTA) when used in pulpotomy treatments in primary molars. METHODS: A total of 23 primary molars received a pulpotomy treatment using white MTA followed by stainless steel crown restoration and controlled 6 months after treatment. RESULTS: Clinical and radiographic success was 100% as none of the molars showed any clinical or radiographic pathological signs. Reparative dentin deposition was found in some of the cases: stenosis was present in 69.2% of the pulp canals from mandibular molars and formation of dentin bridges was seen in 11.5% of the pulp canals from mandibular molars 6 months after treatment with white MTA.