Pulp Therapy for the Young Permanent Dentition

Evaluation of the modified 3Mix-Simvastatin combination in non-instrumental endodontic therapy of necrotic primary molars: A two-arm randomized controlled trial

OBJECTIVE

This study aimed to assess the clinical and radiographic outcomes of non-instrumentation endodontic treatment (NIET) using a modified antibiotic mix of cefixime, ciprofloxacin and metronidazole with simvastatin (an anti-inflammatory, bone regeneration drug) on necrotic primary molars compared to conventional pulpectomy to help preservation of necrotic primary teeth until its natural exfoliation.

MATERIALS AND METHODS

Forty mandibular primary second molars with necrotic pulp tissue from 38 healthy patients aged between 4 and 8 years were randomly assigned to two groups with a 1:1 allocation ratio. Group A teeth underwent conventional root canal treatment. The procedure involved a two-visit approach, employing k-files and h-files during the initial visit, followed by the application of calcium hydroxide paste as canal dressing between visits, while Group B teeth were treated with 3Mixtatin. All teeth were clinically evaluated after 1, 3, 6, and 12 months, and radiographically at 3, 6, and 12 months. Two external examiners assessed the results. Data analysis was conducted using a chi-square test at a 0.05 significance level.

RESULTS

At the end of the follow-up interval, 90% of teeth in each group exhibited no clinical signs or symptoms. Additionally, inter-radicular radiolucency healing occurred in 75% of cases in the NIET group and 89.5% in the conventional pulpectomy group. However, no statistically significant difference was found between the two groups.

CONCLUSION

NIET using 3Mixtatin seems to be a good alternative choice to conventional pulpectomy, offering a less complex treatment approach that may help avoid the complications associated with traditional pulpectomy and could be suitable for teeth with shorter roots.

The Potential Application of Human Gingival Fibroblast-Conditioned Media in Pulp Regeneration: An In Vitro Study

Regenerative endodontic treatment based on tissue engineering has recently gained interest in contemporary restorative dentistry. However, low survival rates and poor potential differentiation of stem cells could undermine the success rate of pulp regenerative therapy. Human gingival fibroblast-conditioned medium (hGF-CM) has been considered a potential therapy for tissue regeneration due to its stability in maintaining multiple factors essential for tissue regeneration compared to live cell transplantation. This study aimed to investigate the potency of hGF-CM on stem cells from human dental pulp (DPSC) in pulp regeneration. A series of experiments confirmed that hGF-CM contributes to a significant increase in proliferation, migration capability, and cell viability of DPSC after H2O2 exposure. Moreover, it has been proved to facilitate the odontogenic differentiation of DPSC via qRT-PCR, ALP (alkaline phosphatase), and ARS (Alizarin Red S) staining. It has been discovered that such highly upregulated odontogenesis is related to certain types of ECM proteins (collagen and laminin) from hGF-CM via proteomics. In addition, it is found that the ERK pathway is a key mechanism via inhibition assay based on RNA-seq result. These findings demonstrate that hGF-CM could be beneficial biomolecules for pulp regeneration.

Fracture Resistance of Equine Cheek Teeth With and Without Occlusal Fissures: A Standardized ex vivo Model

Background:Ex vivo fracture models are frequently used in human dentistry to provide insights in the fracture mechanisms of teeth. Equine cheek teeth fractures are an important dental pathology, but there has been no research performed to examine the fracture resistance ex vivo.

Objective: To evaluate the fracture resistance of equine cheek teeth and identify anatomical predictors that might influence fracture resistance in healthy teeth. It was further evaluated if the presence of a fissure caused a decrease in fracture resistance.

Study design:Ex vivo experimental design.

Methods: Individual cheek teeth were subjected to a compression load in a universal testing machine until fracture occurred. Testing was performed in two study groups. A first group of healthy cheek teeth was tested to examine anatomical predictors on fracture resistance. A second group comprised cheek teeth with occlusal fissures and an equal number of age- and size-matched fissure-free teeth as controls. The effect of possible predictors on fracture resistance was investigated by regression analysis.

Results: In the first group, fracture resistance was significantly influenced by the location on the tooth where testing was performed in both maxillary (p < 0.001) and mandibular teeth (p < 0.001). Additional significantly associated factors were Triadan number in mandibular (p = 0.009) and the mesiodistal length of the occlusal surface of maxillary teeth (p = 0.01). Experimentally induced crown fractures that extended below the simulated bone level were more frequently associated with pulp horn exposure (p < 0.001). In the second group, significant lower fracture loads were recorded in teeth with fissures (mandibular p = 0.006; maxillary p < 0.001), compared to fissure-free teeth.

Main limitations: This ex vivo model does not imitate the in vivo masticatory forces and lacks the shock-absorbing properties of the periodontal ligament.

Conclusions: The methodology used in this study provides an ex vivo experimental set-up to test fracture resistance of equine cheek teeth enabling evidence-based research to examine the potentially weakening effects of tooth pathology and its treatments. Crown resistance to fracture differed along the occlusal surface of healthy equine cheek teeth, and the presence of fissures further decreased fracture resistance.

Pre- and peri-operative factors influence autogenous tooth transplantation healing in insufficient bone sites

Background

The amount of bone remaining at the transplant site for autogenous tooth transplantation can facilitate successful healing. Therefore, this retrospective study evaluated the factors influencing the healing of 50 successful autogenous tooth transplantations with insufficient bone support at the transplanted site without a bone graft.

Methods

The factors were classified as pre- and peri-operative factors, and the healing outcomes were clinical and radiographic observations. The factors were statistically analyzed using the chi-square test to identify correlations between the pre- and peri-operative factors and the clinical and radiographic outcomes. The T-test or one-way analysis of variance was used to compare the percent bone change in each factor.

Results

The results indicated that gingival healing was delayed in the intra-arch transplantations, and pulp obliteration was seen earlier when transplanted in the maxilla. Patients under 18-years-old demonstrated a greater percent bone change than the over 18-year-old patients, while the peri-operative variables did not have a relationship with clinical healing and the amount of bone change over 12 months. Furthermore, the percent bone change significantly increased during the first three months.

Conclusions

In conclusion, pre-operative factors, age and transplant site, influenced the healing rate of autogenous transplanted teeth. In contrast, the peri-operative factors were not related with the clinical and radiographic outcomes. Generating the least trauma to the periodontal ligament cells is the most important concern.