Evaluation of Glyde File Prep in combination with sodium hypochlorite as a root canal irrigant

The purpose of this study using a scanning electron microscope was to investigate the efficacy of four different irrigation techniques after canal preparation with Profile Ni-Ti rotary instruments. A modified technique for the use of Glyde File Prep is proposed. Forty anterior teeth were divided into four groups, instrumented, and irrigated as follows: physiological solution (group A), 2.5% sodium hypochlorite (group B), 2.5% sodium hypochlorite and Glyde File Prep (group C), and 2.5% sodium hypochlorite and Glyde File Prep applied at the end of the preparation with sterile paper points (group D). After scanning electron microscopic evaluation at three different levels, debris, smear layer, and dentinal tubules were scored. Groups A and B had significantly more smear layer and less open tubules on the canal walls compared with the group C and group D samples. Differences in the mean amount of debris between group A samples and other irrigation regimes were statistically significant.

Efficacy of a self-curing adhesive-resin cement system on luting glass-fiber posts into root canals: an SEM investigation

PURPOSE

The aim of this study was to evaluate the efficacy of a new bonding-luting system in resin tag, adhesive lateral branch, and hybrid layer formation when used in combination with an experimental fiber post.

MATERIALS AND METHODS

Thirty anterior teeth extracted for periodontal reasons were selected for this study. They were endodontically treated and randomly divided into three groups of 10 samples each: group 1 = Excite light-cured bonding agent in combination with Variolink II resin cement; group 2 = Excite dual-cured bonding agent self-activated by an experimental microbrush in combination with MultiLink resin cement; and group 3 = one-step bonding system in combination with Dual Link resin cement. In groups 1 and 3, the primer-adhesive solution was light cured before placing the resin cement and the post, whereas in group 2 the adhesive/luting materials were not light cured. Twenty FRC Postec translucent posts (groups 1 and 2) and 10 EndoAesthetic translucent fiber posts (group 3) were used. One week later, the root samples were processed for scanning electron microscopic (SEM) observations.

RESULTS

Microscopic examinations of restored interfaces from group 2 revealed a resin-dentin interdiffusion zone higher than that seen in samples from groups 1 and 3 (P < .05). At the apical and middle thirds, the samples from group 2 showed significantly more resin tags than the other two groups.

CONCLUSION

The dual-cure self-activating system showed a more uniform resin tag and resin-dentin interdiffusion zone formation along root canal walls than light-curing systems.

Efficacy of different adhesive techniques on bonding to root canal walls: an SEM investigation

OBJECTIVES

Recently, several adhesives have been proposed for bonding fiber posts into root canals. The aim of this study was to evaluate the influence of four adhesive procedures in resin tag, adhesive lateral branch and resin dentin interdiffusion zone (RDIZ) formation when used to bond fiber posts.

METHOD

Forty anterior teeth, extracted for periodontal reasons and endodontically treated, were selected for this study. The samples were randomly divided into four groups of ten samples each. Group 1: One Step applied with the small brush provided by the manufacturer and LC (Light-cured before resin cement application)+Dual Link resin cement; Group 2: One Step applied with a thin microbrush LC+Dual Link resin cement; Group 3: One Step applied with a small brush (Not light-cured)+Dual Link resin cement; Group 4: All Bond 2+C & B resin cement (as control). In Group 2 and 4 the adhesive system and resin cement were used strictly following manufacturers' instructions. In Group 1, One Step was applied using a thin microbrush, while in the other groups by a small brush. In Group 1 and 2 the priming-adhesive solution of the "one-bottle" system was light-cured before placing the resin cement and the post, whereas in Group 3 the adhesive/resin cement combination was light cured through the translucent post. Forty translucent posts (RTD, France) were used. A week later, the root samples were processed for SEM observations.

RESULTS

Microscopic examination of restored interfaces of Group 1 showed a higher % (P<0.05) of RDIZ than those found in samples of Group 2, 3 and 4. In Group 2, 3 and 4 samples RDIZ morphology was well detectable and uniform in the first two thirds of root canals while in the apical third the RDIZ was not uniformly present. No statistically significant differences were found among the groups coronally, whereas apical and middle thirds of Group 1 showed significantly more resin tags than the other three Groups. In the apical third of Group 2, 3 and 4 samples, the resin tags showed a less uniform morphology and a shorter length than those found in the other two thirds.

SIGNIFICANCE

A microbrush might clinically be used for bonding fiber posts into the root canal. When a microbrush was used, the bonding mechanism created between root canal dentin and bonding system was uniform along canal walls and more predictable.

[Some specific aspects of dentistry's professional responsibility: tooth extraction surgery, prosthodontics, implantology and HIV infection]

In the last decades the problem of professional responsibility of the doctors went through deep conceptual re-examination. Some criteria, both general and more technically legal, are presented in order to correctly evaluate the professional liability. Then some specific aspects of the object are examined, such as the damaging of the inferior alveolar nerve after dental extraction, the problems concerning dental prosthetics and implants as well as the questions about HIV infection, acquired by patients or collaborators of the dentist, in his office.

Nasoduodenal feeding of the critically ill child

Malnutrition frequently occurs among hospitalized children (19, 23, 24) and is associated with increased rates of morbidity and mortality (3, 5). Because of this hypercatabolic condition, a critically ill patient may undergo a process of acute malnutrition within a few days (7, 27, 34). The nutritional or metabolic support provided in these situations is usually by the parenteral or enteral route, depending on the presence of a functioning digestive tract. When exclusively parenteral feeding is used, prolonged fasting may deprive the intestine of specific nutrients and reduce its function of nutrient processing and absorption for lack of a substrate, with the consequent occurrence of atrophy. Clinical and experimental studies have demonstrated the advantages of the enteral route, which is more physiological, has a lower rate of complications and involves easier administration when compared to the parenteral route. Experimental studies (15, 21) have shown a hypoplastic response of the intestinal mucosa of rats after 3 days of parenteral nutrition when compared to controls submitted to enteral feeding. This response was measured in terms of mucosal weight, villus hypoplasia, DNA protein content, enzyme activity, and pancreatic function. Similar changes detected in clinical studies were rapidly reversed to normal after feeding by the digestive route (13). It is suggested that the mechanism of these alterations may involve the absence of intraluminal amino acids needed for enzyme synthesis rather than the lack of specific substrates inducing enzyme production.(ABSTRACT TRUNCATED AT 250 WORDS)