The effect of glass ionomer and adhesive cements on substance P expression in human dental pulp

OBJECTIVES: The purpose of this study was to quantify the effect of glass ionomer and adhesive cements on SP expression in healthy human dental pulp. Study DESIGN: Forty pulp samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. In thirty of these premolars a Class V cavity preparation was performed and teeth were equally divided in three groups: Experimental Group I: Glass Ionomer cement was placed in the cavity. Experimental Group II: Adhesive Cement was placed in the cavity. Positive control group: Class V cavities only. The remaining ten healthy premolars where extracted without treatment and served as a negative control group. All pulp samples were processed and SP was measured by radioimmunoassay. RESULTS: Greater SP expression was found in the adhesive cement group, followed by the glass ionomer and the positive control groups. The lower SP values were for the negative control group. ANOVA showed statistically significant differences between groups (p < 0.0001). Tukey HSD post hoc tests showed statistically significant differences in SP expression between negative control group and the 3 other groups (p < 0.01). Differences between the cavity-only group and the two experimental groups were also statistically significant (p < 0.05 and p < 0.01 respectively). There is also a statistically significant difference between the two experimental groups (p < 0.01). CONCLUSIONS: These findings suggest that adhesive cements provoke a greater SP expression when compared with glass ionomer

The effect of glass ionomer and adhesive cements on substance P expression in human dental pulp.

OBJECTIVES: The purpose of this study was to quantify the effect of glass ionomer and adhesive cements on SP expression in healthy human dental pulp. STUDY DESIGN: Forty pulp samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. In thirty of these premolars a Class V cavity preparation was performed and teeth were equally divided in three groups: Experimental Group I: Glass Ionomer cement was placed in the cavity. Experimental Group II: Adhesive Cement was placed in the cavity. Positive control group: Class V cavities only. The remaining ten healthy premolars where extracted without treatment and served as a negative control group. All pulp samples were processed and SP was measured by radioimmunoassay. RESULTS: Greater SP expression was found in the adhesive cement group, followed by the glass ionomer and the positive control groups. The lower SP values were for the negative control group. ANOVA showed statistically significant differences between groups (p<0.0001). Tukey HSD post hoc tests showed statistically significant differences in SP expression between negative control group and the 3 other groups (p<0.01). Differences between the cavity-only group and the two experimental groups were also statistically significant (p<0.05 and p<0.01 respectively). There is also a statistically significant difference between the two experimental groups (p<0.01). CONCLUSION: These findings suggest that adhesive cements provoke a greater SP expression when compared with glass ionomer.

Effect of experimentally induced occlusal trauma on substance p expression in human dental pulp and periodontal ligament.

INTRODUCTION: The purpose of this study was to quantify the effect of occlusal trauma experimentally induced with occlusal interferences on substance P (SP) expression in healthy human dental pulp and periodontal ligament. METHODS: Twenty-eight human dental pulp and periodontal ligament samples were obtained from healthy premolars in which extraction was indicated for orthodontic reasons. Before extraction, occlusal trauma was induced with experimental occlusal interferences in half of these premolars by placing a resin block over their occlusal surface and submitting patients to chew gum for 30 minutes. The remaining healthy premolars were extracted without occlusal trauma and served as a control group. All dental pulp and periodontal ligament samples were processed, and SP was measured by radioimmunoassay. RESULTS: There was 45% and 120% greater SP expression in dental pulp and periodontal ligament, respectively, of teeth with experimentally induced occlusal trauma. Paired t test showed statistically significant differences for both human dental pulp and periodontal ligament (P = .02 and P < .001, respectively) of teeth submitted to occlusal trauma when compared with control group values. CONCLUSIONS: SP expression in human dental pulp and periodontal ligament increases when teeth are submitted to occlusal trauma experimentally induced with occlusal interferences.

The effect of three different rotary instrumentation systems on substance P and calcitonin gene-related peptide expression in human periodontal ligament.

INTRODUCTION: The purpose of this study was to quantify the effect of three different rotary root canal preparation systems on substance P and calcitonin gene-related peptide expression in healthy human periodontal ligament. METHODS: Fifty periodontal ligament samples were obtained from healthy premolars in which extraction was indicated for orthodontic reasons. Before extraction, 40 of these premolars were equally divided into four groups, and root canals were prepared using four different systems: the ProTaper Universal rotary system, the RaCe rotary system, the Mtwo rotary system, and the hand instrumentation technique. The remaining 10 healthy premolars that were extracted without treatment served as a negative control group. All periodontal ligament samples were processed, and SP and CGRP were measured by radioimmunoassay. RESULTS: Greater SP and CGRP expression were found in the ProTaper Universal group followed by the hand instrumentation group, the RaCe, and the Mtwo groups. The lower SP and CGRP values were for the negative control group. The Kruskal-Wallis test showed statistically significant differences between groups (p < 0.0001). Post hoc Least Significant Difference (LSD) tests showed statistically significant differences in SP and CGRP expression between the negative control group and all the other groups except the Mtwo group. Hand instrumentation also showed statistically significant differences with all the other groups, except the ProTaper Universal group. Differences between the three rotary systems were also statistically significant. CONCLUSION: SP and CGRP expression in periodontal ligament increases when teeth are prepared with ProTaper Universal and RaCe rotary instrumentation systems as well as with hand instrumentation. Mtwo maintains SP and CGRP levels.

Neuropeptides in dental pulp: the silent protagonists.

Dental pulp is a soft mesenchymal tissue densely innervated by afferent (sensory) fibers, sympathetic fibers, and parasympathetic fibers. This complexity in pulp innervation has motivated numerous investigations regarding how these 3 major neuronal systems regulate pulp physiology and pathology. Most of this research is focused on neuropeptides and their role in regulating pulpal blood flow and the development of neurogenic inflammation. These neuropeptides include substance P, calcitonin gene-related peptide, neurokinin A, neuropeptide Y, and vasoactive intestinal polypeptide among others. The purpose of this article is to review recent advances in neuropeptide research on dental pulp, including their role in pulp physiology, their release in response to common dental procedures, and their plasticity in response to extensive pulp and dentin injuries. Special attention will be given to neuropeptide interactions with pulp and immune cells via receptors, including studies regarding receptor identification, characterization, mechanisms of action, and their effects in the development of neurogenic inflammation leading to pulp necrosis. Their role in the growth and expansion of periapical lesions will also be discussed. Because centrally released neuropeptides are involved in the development of dental pain, the pain mechanisms of the pulpodentin complex and the effectiveness of present and future pharmacologic therapies for the control of dental pain will be reviewed, including receptor antagonists currently under research. Finally, potential clinical therapies will be proposed, particularly aimed to manipulate neuropeptide expression or blocking their receptors, to modulate a variety of biologic mechanisms, which preliminary results have shown optimistic results.

Reabsorción radicular en dentición permanente: artículo de revisión / Root resorption in permanent dentition. A review

La reabsorción radicular es un proceso en el cual se pierde tejido dental, y donde interactúan células inflamatorias, clásticas y células propias de cada tejido. Dentro de los factores etiológicos asociados a esta patología, se encuentra la presencia de estímulos bacterianos, mecánicos o químicos, los cuales producen cambios dentro de los tejidos que dan como resultado la formación de células gigantes multinucleadas responsables de dicho proceso. La aparición de procesos de reabsorción se debe a la presencia de un tejido conectivo vascularizado y presencia de un estímulo inflamatorio. Esta entidad puede ser clasificada; según su localización y naturaleza, en: interna, externa, inflamatoria transitoria o progresiva, cervical y por reemplazo. El objetivo de este artículo es describir los tipos de reabsorción que pueden presentarse para poder permitir un diagnóstico certero, teniendo en cuenta la etiología de cada una de ellas.

Comparación entre la preparación invertida y la preparación telescópica para evitar exacerbaciones en dientes necróticos con lesión periapical observada radiográficamente / Comparison between the crown-down pressureless technique and the step-back tecbique to prevent exacerbations on necrotic teeth with radiographic signs of periapical lesion

El propósito de este estudio prospectivo fue comparar el uso de la técnica de preparación invertida y la técnica de preparación de conductos necróticos con lesión periapical observada radiográficamente, para encontrar cuál evita que se presente una exacerbación en el paciente. Se estudiaron 245 pacientes, los cuales fueron divididos en dos grupos: 135 paciente a los que se les aplicó la técnica de preparación telescópica, y 110 a los que se les realizó la técnica de preparación invertida.