Biocompatibility of NeoMTA Plus® versus MTA Angelus as delayed furcation perforation repair materials in a dog model.

BACKGROUND: The biocompatibility of NeoMTA Plus® (Avlon BioMed Inc., Bradenton, Fl) as a furcal perforation repair material is not fully understood. This study compares the biocompatibility of Mineral Trioxide Aggregate (MTA Angelus) and NeoMTA Plus® as delayed furcation perforation repair materials. METHODS: Pulpotomy and root canal obturation were performed in 72 premolars in six mongrel dogs and then a standardized furcal perforation was performed. The coronal access was left open for three weeks. After curetting, cleaning and drying of the perforations, these teeth were divided into three equal groups (N = 24 teeth/ 2 dogs each) according to the material used for perforation repair; group I: NeoMTA Plus®, group II: MTA Angelus and group III: no material (positive control). The coronal access cavities were sealed with a filling material. The inflammatory cell count and qualitative pathology (presence of calcific bridge, configuration of fibrous tissue formed, examination of tissue surrounding the furcation area, histology of intraradicular bone and the inflammatory nature of tissues) were carried out after one week (subgroup A, N = 8 teeth), one month (subgroup B, N = 8 teeth) and three months (subgroup C, N = 8 teeth). The inflammatory cell count was expressed as mean ± SD and statistically analyzed. P-value < 0.05 was considered significant. RESULTS: In all subgroups, the control group exhibited the highest number of inflammatory cell count, followed by MTA Angelus group and the least inflammatory cell count was shown by NeoMTA Plus® group. There was a significant difference in the inflammatory cell count between the NeoMTA Plus® and MTA Angelus after one week (P < 0.05) while no significant differences were recorded between them after one month and three months (P > 0.05). In contrast to group II, there was no significant differences in inflammatory cell count between the subgroups in groups I and III (P > 0.05). NeoMTA Plus® exhibited better qualitative pathological features than MTA Angelus after one week and nearly similar features after one month and three months of repair. CONCLUSION: NeoMTA Plus® has a better early biocompatibility than MTA Angelus after one week of delayed furcation perforation repair and a similar late biocompatibility after one month and three months.

Biological evaluation of a new pulp capping material developed from Portland cement.

This study evaluates the biological properties of a new pulp capping material developed from Portland cement. This study was conducted on 48 teeth in 4 dogs (12 teeth/dog). The dogs were classified into two equal groups (n=24 teeth) according to the evaluation period including: group A (3 weeks) and group B (3 months). Each group was further subdivided into three equal subgroups (n=8 teeth) according to the capping material including: subgroup 1: mineral trioxide aggregate (MTA), subgroup2: Portland cement+10% calcium hydroxide+20% bismuth oxide (Port Cal) and subgroup 3: Portland cement+bismuth oxide. After general anesthesia, a class V buccal cavity was prepared coronal to the gingival margin. After pulp exposure and hemostasis,the capping materials and glass ionomer filling were placed on the exposure sites. All histopathological findings, inflammatory cell count and dentin bridge formation were recorded. Data were analyzed statistically. After 3 months, the histopathological picture of the pulp in subgroup 1 showed normal pulp, continuous odontoblastic layer and complete dentin bridge formation while subgroup 2 showed partial and complete dentin bridge over a normal and necrotic pulps. Subgroup 3 showed loss of normal architecture, areas of necrosis, complete, or incomplete dentin bridge formation, attached and detached pulp stones and fatty degeneration in group B. For group A, MTA subgroup showed the least number of inflammatory cell infiltrate followed by Port Cal subgroup. While subgroup 3 showed the highest number of inflammatory cell infiltrate. For group B, the mean inflammatory cell count increased with the three tested materials with no statistical difference. Regarding dentin bridge formation at group A, no significant differences was found between subgroups, while at group B, MTA subgroup exhibited significantly higher scores than other subgroups. In conclusion, addition of calcium hydroxide to Portland cement improves the dentin bridge formation qualitatively and quantitatively.

Histomorphometric study of the root apex of mandibular premolar teeth: an attempt to correlate working length measured with electronic and radiograph methods to various anatomic positions in the apical portion of the canal.

One aim of this study was to attempt to relate the position of the cementodentinal junction (CDJ) and the apical constriction to that of the apical foramen in mandibular premolars, as well as to measure the canal diameter at these various points. Another aim was to evaluate how electronic working length determination by Root ZX and radiographic method of working length determination correlated to the location of these various positions. The results showed that CDJ was detected at average distance of 0.3 mm from apical foramen with average canal diameter of 0.32 mm, whereas the apical constriction was detected at average distance from apical foramen of 1.2 mm with canal diameter of 0.22 mm. There was a statistically significant difference between file-tip position from apical foramen in group I working length measured by Root ZX and group II working length measured radiographically. Also this significant difference was found between file-tip position in both groups and CDJ and apical constriction. The average canal diameter at 0.5, 1, and 1.5 mm from apical foramen was 0.33 +/- 0.11, 0.28 +/- 0.06, and 25 +/- 0.05 mm, respectively.

ProRoot MTA, MTA-Angelus and IRM used to repair large furcation perforations: sealability study.

The ability of two mineral trioxide aggregate (MTA) compounds and Intermediate Restorative Material (IRM) to seal large furcation perforations were evaluated using a dye-extraction leakage method. The furcation perforations were repaired with and without the use of internal matrix before placement of repair material. Eighty extracted human mandibular first molars were divided into positive (n = 10), negative (n = 10), and three experimental groups (n = 20) according to the repair material used. Each experimental group was divided into two subgroups (n = 10) according to whether internal matrix was used or not. Dye leakage was tested from an orthograde direction, and dye extraction was performed using full concentration nitric acid. Dye absorbance was measured at 550 nm using spectrophotometer. ProRoot MTA (Maillfer, Dentsply, Switzerland) with and without internal matrix and MTA-Angelus (Angelus, Londrina, PR, Brazil) with internal matrix showed the least dye absorbance. IRM (Caulk, Dentsply, Milford, DE) without internal matrix showed the highest dye absorbance. IRM with internal matrix and MTA-Angelus without internal matrix had insignificant difference and came at intermediate level between the other groups.