Biomedical subjects

L W M van der Sluis

Publications and source records attributed to L W M van der Sluis.

10 recordsLinked to original sources

PubMed2007

The evaluation of removal of calcium hydroxide paste from an artificial standardized groove in the apical root canal using different irrigation methodologies.

AIM: To evaluate the capacity to remove a calcium hydroxide (Ca(OH)2) paste from the root canal and to evaluate the efficacy of Ca(OH)2 removal during passive ultrasonic irrigation using either sodium hypochlorite (NaOCl) or water as an irrigant. METHODOLOGY: Sixteen mandibular premolars were used. Each root was prepared to the apical foramen using GT instruments of size 30, 0.06 taper. Each root was split longitudinally. In one half of the root, a groove was cut in the canal wall 2-6 mm from the apex which was then filled with a Ca(OH)2 paste. Subsequently the roots were reassembled. In group 1 (n = 16), the teeth were ultrasonically irrigated using 50 mL 2.0% NaOCl as the irrigant. Group 2 (n = 16) was treated in the same manner as group 1, but using 50 mL water in place of the NaOCl. In group 3 (n = 16), the teeth were irrigated by syringe injection of 50 mL 2.0% NaOCl. The quantity of remaining Ca(OH)2 in the groove was scored and the data analysed with Kruskal-Wallis and Mann-Whitney tests. RESULTS: The difference in remaining Ca(OH)2 between all groups was statistically significant (P < 0.001). Group 1 had significantly lower scores than group 2 (P < 0.001) and group 3 (P = 0.002), but there was no significant difference between groups 2 and 3 (P = 0.765). CONCLUSIONS: Passive ultrasonic irrigation with 2% NaOCl was more effective in removing Ca(OH)2 paste from artificial root canal grooves than syringe delivery of 2% NaOCl or water as irrigant.

Calcium Hydroxide↗

PubMed2006

The influence of volume, type of irrigant and flushing method on removing artificially placed dentine debris from the apical root canal during passive ultrasonic irrigation.

AIM: To determine the influence of volume, irrigant and method of flushing on the removal of artificially-placed dentine debris from the apical part of root canals during passive ultrasonic irrigation. METHODOLOGY: Access cavities were prepared in 15 canine teeth and their root canals instrumented to size 20, 0.10 taper. Each root was split longitudinally, forming two halves. A groove was cut in the canal wall 2-6 mm from the apex in each half which was then filled with dentine debris prior to the roots being reassembled. All canals were ultrasonically irrigated, using a size 15, 0.02 taper smooth wire to a length of 21 mm that was placed in the canal to the apical foramen. In group 1 the canal was flushed with a continuous flow of 50 mL 2% sodium hypochlorite (NaOCl). In group 2 the continuous flow was not used but the canal was flushed with 12 mL 2% NaOCl, at a rate of 2 mL 30 s-1 using a syringe. Group 3 was treated in the same way as group 2 but the canal was flushed with 6 mL 2% NaOCl, at a rate of 2 mL min-1. Group 4 was treated in the same way as group 1 but water was used as the irrigant. Before and after irrigation, images of the grooves were captured and stored. The quantity of dentine debris in the groove was evaluated. The differences in debris scores between the experimental groups were analysed with the Kruskal-Wallis test and the Mann-Whitney U-test. The level of significance was set at P=0.05. RESULTS: The difference between all groups was statistically significant (K-W test P<0.001). Groups 1, 2 and 3 differed significantly from group 4 (P<0.001); there was no significant difference between groups 1, 2 and 3 (P=0.550). CONCLUSIONS: Syringe delivery of 2% NaOCl (6 and 12 mL) was as effective as a continuous flow of 2% NaOCl (50 mL). Water was not effective in removing dentine debris from grooves in the apical portion of root canals.

Cuspid↗

PubMed2005

An evaluation of the quality of root fillings in mandibular incisors and maxillary and mandibular canines using different methodologies.

OBJECTIVES: To evaluate the quality of root fillings in mandibular incisors and maxillary and mandibular canines using different methodologies of evaluation, namely radiographs, the fluid transport test and the percentage of gutta-percha (PGP), and to determine if a correlation occurs between the results of the different methodologies used. METHODS: One group of mandibular incisors with oval canals (n=20) and one group of maxillary and mandibular canines (n=20) were instrumented and obturated by cold lateral compaction using AH 26 as the sealer. The filled roots were bucco-lingually and mesio-distally radiographed. Using a scoring system, the quality of each root filling was radiographically evaluated, the higher the score the poorer the quality. Fluid transport along the root filling was then measured using a fluid transportation device. Each root was horizontally sectioned 4 and 6mm from the apex. Images of the cross-sections were taken, using a microscope and a digital camera. Images were scanned into a PC as TIFF images. Using a KS 100 Imaging system the canal area and the gutta-percha filled areas were measured. The percentage of gutta-percha filled areas was calculated. RESULTS: Considering the radiographic scores of the two different projections together the score was significantly higher for the mandibular incisors than for the canines (P=0.039). The radiographic score was significantly higher for the mesio-distal radiograph in comparison with the bucco-lingual radiograph (P=0.0001), for the canines as well as the incisors. Using only the bucco-lingual radiograph there was no significant difference between the mandibular incisors and the canines (P=0.992). The mandibular incisors displayed significantly more fluid transport than the canines (P=0.049). A significantly greater percentage of gutta-percha filled areas was found in the cross-sections of canines as compared to the cross-sections of mandibular incisors (P=0.000001). The correlation between the radiographic score of the mesio-distal radiograph and the PGP 4 and 6mm was significant (P=0.013). There was no significant correlation between the FT and the radiograph or the FT and the PGP. CONCLUSIONS: The quality of the root fillings in oval canal-mandibular incisors may be compromised.

Bismuth↗

PubMed2005

A comparison between a smooth wire and a K-file in removing artificially placed dentine debris from root canals in resin blocks during ultrasonic irrigation.

AIM: To compare the efficacy of a smooth wire with a conventional K-file, in removing dentine debris from grooves in root canals made in resin blocks, during ultrasonic irrigation. METHODOLOGY: Each resin block containing a standard simulated canal was split longitudinally through the canal, forming two halves. In one canal wall, a standard groove 4 mm in length, 0.2 mm in width and 0.5 mm in depth was cut 2-6 mm from the apical end of the canal, to simulate uninstrumented canal extensions. Each groove was filled with fresh dentine debris mixed with 2% NaOCl to simulate a situation when dentine debris accumulates in uninstrumented canal extensions. Each canal was reassembled by joining the two halves of the resin block by means of wires and sticky wax. In each canal ultrasonic irrigation was performed for 3 min using 2% NaOCl as irrigant. In one group (n = 20) a conventional K-file size 15 was used. In the other group (n = 20) a smooth wire was used which had the same length and diameter as the size 15 K-file. Before and after irrigation, images of each half of the canal with a groove were taken, using a microscope and a digital camera, after which they were scanned into a PC as TIFF images. The quantity of dentine debris in the groove was evaluated using a scoring system: the higher the score, the larger the amount of debris remaining. The score data were analysed by means of the Mann-Whitney U-test. RESULTS: After ultrasonic irrigation, the debris was completely removed from the groove in 35 canals (87.5%), and there was no significant difference between the groups (P = 0.429). CONCLUSIONS: Using a smooth wire during ultrasonic irrigation is as effective as a size 15 K-file in removal of artificially placed dentine debris in grooves in simulated root canals in resin blocks.

Dental Instruments↗

PubMed2005

The efficacy of ultrasonic irrigation to remove artificially placed dentine debris from human root canals prepared using instruments of varying taper.

AIM: To investigate the influence of the taper of root canals on the effectiveness of ultrasonic irrigation to remove artificially placed dentine debris. METHOD: Forty-four maxillary and mandibular canines were selected after bucco-lingual and mesio-distal radiographs indicated that their internal diameters were smaller than the diameters of a size 20, .06 taper System GT instrument (Dentsply Maillefer, Ballaigues, Switzerland). These canines were divided into three groups and prepared using either size 20, .06 taper System GT instruments, size 20, .08 taper or size 20, .10 taper System GT instruments. Each root was then split longitudinally through the canal, forming two halves. In one canal wall, a standard groove was cut 2-6 mm from the apex, to simulate un-instrumented canal extensions. Each groove was filled with dentine debris mixed with 2% NaOCl to simulate a situation when dentine debris accumulates in the un-instrumented canal extensions. Each canal was reassembled by joining the two halves of the teeth by means of wires and sticky wax. In each canal ultrasonic irrigation was performed with a size 15 K file using 2% NaOCl as an irrigant. Before and after irrigation, images of each half of the canal with a groove were taken using a microscope and a digital camera, after which they were scanned into a PC as TIFF images. The quantity of dentine debris in the groove was evaluated using a scoring system: the higher the score, the larger the amount of debris. The scores before and after irrigation were compared. The differences in percentage of score reduction between the three groups were analysed by means of one-way anova. RESULTS: After ultrasonic irrigation, the debris score reduced by 74, 81 and 93%, respectively, in the size 20, .06, 20, .08 and 20, .10 taper groups. However, the difference amongst groups was not statistically significant (P = 0.078). CONCLUSION: There was a tendency that ultrasonic irrigation was more effective in removing artificially placed dentine debris from simulated canal extensions from canals with greater tapers.

Analysis of Variance↗

PubMed2005

[Endodontic diagnosis].

In this article endodontic diagnosis is discussed following the clinical diagnostic process. A description is given about pain from endodontic origin and a comprehensive overview of the clinical diagnostic tests is discussed. In the chapter clinical classification of pulpal and periapical disorders all the possible endodontic diagnoses are extensively discussed.

Dental Pulp Diseases↗

PubMed2004

Comparison of mandibular premolars and canines with respect to their resistance to vertical root fracture.

OBJECTIVE: To compare the force required to vertically fracture uninstrumented and instrumented mandibular premolars and canines. METHODS: Two groups of single round-canal mandibular premolars and two groups of single oval-canal mandibular premolars were selected after radiographs indicated an internal long:short diameter of 1 or >2 at a level 5 mm from the apex. In addition, two groups of maxillary and mandibular canines were selected. The root canals of three of these groups (one from each category) were conventionally enlarged using same-sized instruments, while the other three groups were uninstrumented. Each root was mounted in an acrylic resin cylinder, and the force required to cause vertical root fracture (VRF) was measured using an Instron tester. RESULTS: No significant difference in resistance to VRF was found between the round- and oval-canal premolars with (p = 0.9) or without (p = 0.6) instrumentation. The average force required to fracture the uninstrumented premolars and canines was 698 and 566 N, respectively. The average force required to fracture the instrumented premolars and canines was 490 and 554 N, respectively. The force required to fracture the instrumented premolars and canines was 30% (p < 0.05) and 2% (p = 0.9) lower, respectively, than that required to fracture their uninstrumented counterparts. CONCLUSIONS: The instrumented mandibular premolars have a higher risk to fracture than the uninstrumented mandibular premolars.

Bicuspid↗

PubMed2003

The capability of two hand instrumentation techniques to remove the inner layer of dentine in oval canals.

AIM: To evaluate the capability of two hand instrumentation techniques, namely balanced force and circumferential filing, to remove the inner layer of dentine in oval canals. METHODOLOGY: Thirty mandibular incisors with a single oval canal were selected and divided into two equal groups on the basis of their radiographic bucco-lingual internal diameters measured at a level 5 mm from the apex. Two different hand instrumentation techniques, i.e. balanced force and circumferential filing, were used in each group. A modification of the Bramante muffle mould was used to examine the root canal before and after instrumentation at a level 5 mm from the apex. The two images of the root cross-section before and after instrumentation were superimposed on one another. The perimeter of the canal and the length of the arc where the inner layer of dentine had been removed by the instrumentation were measured by means of an image analysis program. The percentage of this arc was calculated. RESULTS: The balanced force method removed the inner layer of dentine from 38.6% of the circumference of the canal wall, as opposed to 57.7% using circumferential filing. The difference was not statistically significant (P = 0.101). CONCLUSION: In oval canals, both the balanced force and circumferential filing techniques left large portions of the canal wall uninstrumented.

Dental Pulp Cavity↗

PubMed2003

Fluid movement along the coronal two-thirds of root fillings placed by three different gutta-percha techniques.

AIM: To compare fluid movement (FM) along the coronal two-thirds of gutta percha/sealer root fillings placed by three different techniques. METHODOLOGY: Three groups consisting of the roots of mandibular incisors were instrumented and obturated by cold lateral compaction (LC), warm vertical compaction (VC) or the single-cone technique (SC), using RoekoSeal Automix (RSA) as the sealer. The apical 4 mm of each root filling was removed, and FM along the remaining 7 mm of the root filling was measured. RESULTS: The VC group displayed more FM than the other two groups (P = 0.023). No significant difference in FM was found between the LC and SC groups (P = 0.629). CONCLUSIONS: The coronal two-thirds of the VC root fillings did not prevent FM when RSA sealer was used.

Dental Cements↗

PubMed2002

A preliminary study of the percentage of gutta-percha-filled area in the apical canal filled with vertically compacted warm gutta-percha.

AIM: The aim of this study was to determine the influence of the width of apical root canals and the depth of heat application during warm vertical compaction on the percentage of gutta-percha-filled area (PGFA) in the apical root canal. METHODOLOGY: Two groups of extracted human canines (total 60) were instrumented and filled with vertically compacted warm gutta-percha up to the apical foramen (AF). Using the Touch 'n Heat device heat was applied 4 mm from the AP in one group and 2 mm in the other. The number of teeth with gutta-percha extrusion was recorded. A horizontal section was cut 1.5 mm from the AF of each tooth. The cross-sectional area of the canal and the gutta-percha was measured using an image-analysis programme. The PGFA was then calculated. Multiple linear regression was performed to investigate the association between the experimental variables and the PGFA, and the occurrence of gutta-percha extrusion. RESULTS: A significant association was seen between the depth of heat application and the PGFA (P= 0.000), and between the canal area and the PGFA (P= 0.038). The average PGFA reached 96.1% when heated to 2 mm, as compared with 87.0% when heated to 4 mm. PGFAs were lower in wide apical canals than in small canals. Gutta-percha extruded in seven teeth (12%) and was independent of experimental variables. CONCLUSIONS: After warm vertical compaction, the quality of adaptation of gutta-percha to the wall of the apical root canal varies; the influencing factors in this study were the depth of heat application and the width of the apical root canal.

Cuspid↗