Dye penetration in dry and water-filled gaps along root fillings.

AIM: The aim of this study was to investigate the influence of hydration in voids along root fillings on methylene blue penetration. METHODOLOGY: A total of 80 human root canals were prepared using a step-back technique and filled with a zinc oxide based sealer and gutta-percha. Leakage along the fillings was measured by a transport fluid model and classified into three categories: gross leakage (GL), slight leakage (SL) and no leakage (NL). Specimens with NL and SL were immersed into methylene blue (MB) 2% for 24 h (group I). Specimens with GL which had wide gaps filled with water were randomly divided into two groups (II, III). Transport air was applied to remove water from gaps only in specimens of group III. All tested specimens from groups II and III were also immersed into MB 2% for 24 h. Each specimen was then split longitudinally and linear measurements of dye penetration were recorded. RESULTS: Group III (with dry gaps) showed significantly more dye penetration than group II. No significant difference was found between group I and group II. CONCLUSIONS: Methylene blue penetrates along root fillings more easily in dry gaps than in water-filled gaps.

Chemical analysis of a dens invaginatus by SEM microanalyses.

A patient with a supernumerary right maxillary lateral incisor with dens invaginatus presented. After extraction, the invaginated area of the tooth as well as another of similar ages but with normal hard tissues, were prepared for scanning electron microscopic observation. Outer and invaginated enamels were identified the latter showing more density. Chemical analysis by the scanning microanalyses revealed differences in mineral contents between: a) the external and cut surface of the outer and the invaginated enamel, and b) the external and cut surface of the normal tooth. The outer and invaginated enamels are quite different concerning the quantity and quality of minerals, the latter having no magnesium at all. Magnesium was also non existent in the dentin.

Apexification with the use of calcium hydroxide: a clinical study.

The purpose of this study was to examine the type of root-end closure achieved with the apexification technique, in relation to age, sex and stage of root development. Data from 34 cases, in which apexification was performed, were analyzed. In all cases chemically pure powder Ca (OH)2 with anaesthetic solution was used. The age of 12 patients was between 27-40 years (1 male and 11 females) and of the other 22 was between 8-20 years (14 males and 8 females). Continuation of root development was achieved in 6 cases, continuation and bridge formation was revealed in three cases, bridge formation was seen in 21 cases and finally in 4 cases no root-end closure was noticed. From the above results it was evident that the bridge formation was the most common form of root-end closure. Statistical analysis revealed a strong correlation between the type of root-end closure and the stage of root development prior to apexification in relation to: a) sex and b) age. Thus the bridge formation was the most common type (87.5%) in the group of females. Also in the same sex group concerning the stage 4 of root development bridge formation was again the type of root-end closure (92.85%). Finally, it was found that in age group B (27-45-years-old), with stage 4 of root development, the bridge formation was the most common type of root-end closure (90%).

Vertical root fractures.

In this study, I review, clinically and radiographically, 303 patients with 460 single or multirooted endodontically treated teeth. In all teeth, the therapy was performed by me with the use of final restoration of the crown with or without post and full cast crown coverage after treatment. The teeth were functioning for at least 3 years, without having received any other type of dental work since then. I evaluated the existence of vertical root fracture, the function of the teeth, the type of root canal therapy, the type and length of the post, and the type of retention of the post used in all 460 teeth. After statistical evaluation of the results, I found that 3.69% of the teeth had had vertical root fracture. Computer analysis, simple correlation hypothesis, and distribution method with 1 degree of freedom revealed significant correlation between vertical root fracture and the technique of instrumentation and obturation of the canal (p = 0.025), the length of the post (p = 0.05), and the existence of the post (p = 0.05). On the contrary, I found no correlation between root fracture and type of retention of the prefabricated post used with respect to the method of obturation.

[Root canal volume]. / Ypologismos tou ogkou ton rizikon solenon.

In this research we used 180 noncarious teeth, 15 from each kind, in which we cut the anatomic crown. After that we weighted the roots, each group separately, before and after the root canal obturation with the technique of lateral condensation of gutta percha and Grossman's sealer. The difference of the two weights represent the overload of the tooth after obturation. Then using mathematical rules we configured out the mean volume of the root canal of each group and the mean value of the diameter of the orifice of the canal of each group of teeth.

Enamel hypoplasia of a maxillary central incisor.

This article describes a case of a permanent central incisor with enamel hypoplasia. A 7-year-old patient had suffered an injury in a car accident when she was 2 1/2 years old. The maxillary right central deciduous incisor was lost in the accident. At the time of examination a fistula was present buccally to the maxillary right permanent incisor, which had erupted only 3 mm into the mouth. The maxillary left central incisor had erupted fully. After clinical and radiographic examination the lost deciduous incisor was found in the bone buccally to the permanent incisor. The deciduous tooth was extracted surgically, the fistula healed and the gingiva became normal. The permanent incisor had a 3-mm-wide zone of hypoplastic enamel on the buccal surface of the crown.

Dens invaginatus with an open apex: a case report.

A severe case of dens invaginatus is described on an upper central incisor that was associated with a discharging sinus tract. The outer pulp chamber contained vital tissue while the inner one contained necrotic material. Root canal treatment was carried out with long-term calcium hydroxide dressings to induce apical closure. The canal system was subsequently filled and the tooth followed up for 4 years.

[Study in SEM of the number and size of the main and accessory foramens of the first lower premolars]. / Melete ton akrorrizion ton proton kato progomphion sto elektroniko mikroskopio saroses (EMS).

The authors in this study have been used the apexes, 4 mm in length, from 93 first lower premolars, from patients over 45 years old. All specimens were prepared for SEM visualization. It was found that in 84.95% of them there was present at least one accessory foramen. All accessory foramens has a diameter less than 100 microns, with a mean value 52 microns. Also in a 74.19% of the 93 teeth, there was present a second main foramen. These foramens had a diameter more than 100 microns, with a mean value 368 microns. Finally it was found that when an extra main foramen was present, the mean value of the diameter remained the same and not smaller than that of the teeth with one main foramen. This may be of a significant clinical value, because this means that the pulp takes extra volumes of blood from these extra foramens.