Current developments in pulp therapy for primary teeth

Cone-beam computed tomography evaluation of shaping ability of kedo-S square and fanta AF™ baby rotary files compared to manual K-files in root canal preparation of primary anterior teeth

BACKGROUND

Pediatric rotary file systems were developed to solve manual file limitations. With many systems available, it may be tricky to select the most appropriate one.

AIM

to assess & compare Kedo-S Square, Fanta-AF™-Baby rotary files with manual K-file concerning removed dentin amount, canal transportation, centric ability & root canal taper using CBCT in primary anterior teeth.

DESIGN

Extracted Seventy-five upper primary anterior teeth with intact 2/3 root length were collected and divided into three groups based on root canal instrumentation, group-I: prepared using K-file, group-II: prepared using Kedo-S Square, and group-III: prepared using Fanta AF™ Baby file. The teeth were imaged with CBCT before & following canal instrumentation. Then, the removed dentin amount was calculated at each root-canal level. The Kruskal-Wallis test was utilized to statistically analyze study data.

RESULT

The difference among the three groups was highly statistically significant at cervical & apical thirds concerning dentin thickness changes on both mesial & distal sides following canal preparation with the least removed dentin in the Kedo-S Square group(P < 0.0001). Regarding transportation & centering ability, a non-significant difference between the three groups was found. 80% of the Fanta AF™ Baby group had good-tapered preparation compared to the Kedo-S Square (72%) and K-file (40%) groups(P < 0.05).

CONCLUSION

Kedo-S Square was preferable to Fanta-AFTM-Baby & manual K-files in primary root canal preparation.

Shaping ability of novel nickel-titanium systems in printed primary molars

BACKGROUND

Manual or mechanized instruments can be used for root canal preparation. Manual instrumentation using K-files is widely used in primary teeth, but there are many limitations. Mechanized root canal preparation can lead to easy access to all canals, decrease instrumentation time, and result in more funnel-shaped root canals, resulting in a more predictable uniform paste fill.

AIM

This study aimed to evaluate the shaping ability and instrumentation time of VDW.ROTATE™ and EdgeTaper Platinum™ during the preparation of resin-printed primary molars. Hand K-files were used as a reference for comparison.

DESIGN

Sixty-six resin-based maxillary second primary molars, obtained from extracted tooth cone-beam computed tomography (CBCT) image and printed on a three-dimensional printer, were divided into three groups: VDW.ROTATE™, EdgeTaper Platinum™, and K-files. The specimens were scanned using CBCT imaging before and after root canal preparation. Images were registered using a dedicated software, and changes (Δ) in the canal area, volume, and untouched canal surface were calculated. Instrumentation time was evaluated. Data were statistically analyzed using the SPSS program.

RESULTS

There was no significant difference among the tested file systems for Δ canal volume and area (p > .05). VDW.ROTATE™, however, showed significantly lower untouched canal surface area than other systems in all roots (p < .001). The VDW.ROTATE™ was found to be significantly faster (6.47 ± 0.39 min) than EdgeTaper Platinum™ (7.71 ± 0.73 min) and K-files (8.22 ± 0.72 min), (p < .05).

CONCLUSIONS

The shaping ability and the instrumentation time were directly influenced by the root canal instrumentation system used during the preparation of resin-printed primary molars, with VDW.ROTATE™ being the faster system and associated with the lower amount of untouched canal surface area.

A Diagnostic Insight of Dental Pulp Testing Methods in Pediatric Dentistry

The accurate diagnosis of pulpal pathology in pediatric dentistry is essential for the success of vital pulp therapy. Pulp testing is often a challenging task due to understanding and cooperation issues of pediatric patients, as well as the particularities of pulpal physiology encountered in primary and immature permanent teeth. Sensibility tests, although still widely used by dental practitioners, are no longer recommended by pediatric specialists mainly due to their subjective nature. Vitality pulp tests have gained popularity in the last decade in light of some encouraging results of clinical studies. However, their use is not a routine practice yet. This paper is a literature review aimed to guide dental practitioners towards selecting the appropriate pulp testing method for their pediatric cases. It provides an overview on a multitude of pulp testing methods and an update in recommendations for primary and immature permanent teeth.

Flowable Urethane Dimethacrylate-Based Filler for Root Canal Obturation in Primary Molars: A Pilot SEM and microCT Assessment

Pulpectomy in deciduous teeth involves endodontic access opening, root canal debridement and obturation with an appropriate filling material. EndoREZ (ER) is the urethane dimethacrylate-based filler, which can be used for root canal obturation in permanent and primary teeth. This observation aimed to evaluate the behavior of the ER as a filler in root canals of two primary molars after the physiological resorption process using the scanning electron microscopy (SEM) and micro-computed tomography (µCT) in second lower molars after their natural exfoliation. The SEM analysis revealed a non-uniform, porous and lacunary structure of ER, visually similar to the resorbed surface of the dentine. The µCT observations demonstrated the differences in the resorption level of the root and material surfaces. The preliminary observations suggest that ER is resorbed faster than root tissues and can therefore be a suitable material for the root canal filling in primary teeth. However, more investigations are needed to support these preliminary findings.

A micro-computed tomographic assessment of root canal preparation with conventional and different rotary files in primary teeth and young permanent teeth

BACKGROUND

Root canals of primary teeth are commonly prepared with endodontic files that are originally manufactured for permanent teeth.

AIM

This micro-computed tomography (micro-CT) study evaluated and compared the changes in root canal morphology after preparation with different conventional and rotary files in primary teeth and young permanent teeth.

DESIGN

Seventy-two extracted primary and permanent molars were selected and randomly assigned to three subgroups according to the file systems used (n = 12/each). After pre-scanning of teeth with micro-CT, root canals were prepared with One Shape and Revo-S rotary systems and conventional endodontic files. After rescanning procedure, changes in canal volume, surface area, uninstrumented surface area, and apical transportation were evaluated. Mann-Whitney U test, Kruskal-Wallis test, and Conover's multiple comparison test were used for statistical analysis (P = .05).

RESULTS

Instrumentation with rotary files resulted in significantly greater volume and surface area of root canals and less uninstrumented areas (P < .001) than with manual files (P < .001). Primary molars showed significantly less apical transportation than permanent teeth (P < .001).

CONCLUSIONS

Preparation of canals with rotary files could be a viable alternative to conventional files in primary teeth. Regardless of the file system used, uninstrumented areas still exist in both primary teeth and permanent teeth.

Pulp Chamber Analysis of Primary Molars Using Micro-Computed Tomography: Preliminary Findings

Purpose: To determine the three-dimensional (3D) tooth morphology of all primary molars and to identify and consolidate positional factors that could potentially have an effect on tooth preparation. Study design: Thirty-one non-carious primary molars were scanned using micro-CT and reconstructed using 3D analysis software. Each pulp horn to its respective cusp tip distance (PHCD) was measured as well as the distances from the pulp chamber to the mesial, distal, lingual and buccal surfaces. One-way ANOVA and post-hoc t-tests were used for data analysis. Results: The mesio-buccal and disto-buccal PHCD was significantly shorter than the mesio-lingual and disto-lingual PHCDs in maxillary second primary molars (P < 0.05). Mesial, distal and lingual walls were thinner than the buccal walls of mandibular molars while in maxillary molars; the mesial and distal walls were thinner than the palatal and buccal walls (P < 0.05). Conclusions: First primary molars have thinner tooth structure surrounding the pulp than second primary molars in the same arch with the exception of the buccal walls of all molars and lingual walls of maxillary molars. The mesial and distal walls are thinner than the buccal walls of all molars and lingual walls in maxillary molars.

Measurement Reliability of the Remaining Dentin Thickness below Deep Carious Lesions in Primary Molars

Aim

This study was carried out to assess the reliability of measurements of the remaining dentin thickness under deep carious lesions as estimated from digital radiographs. The goal is to allow clinicians to correlate the radiographic measurement to the exact value of the remaining dentin thickness. The results obtained will be tested further in a study that will evaluate the histopathologic pulpal state according to the caries’ lesion depth.

Materials and methods

The study was conducted in the Pediatric Dentistry Department at the Lebanese University, in collaboration with the research platform of the same university. Fifty deciduous molars with deep caries on proximal surfaces liable to extraction were collected. Before extraction, a digital in vivo periapical radiograph was taken, followed by manual excavation of the caries. After excavation, another radiograph was taken before the tooth was sectioned through the deepest site of the lesion. Another radiograph was then obtained for each tooth fragment. To evaluate the exact thickness of the remaining dentin, each fragment was measured on a histologic macropho-tograph. The measurements were then compared statistically using a paired-samples t-test, and a correlation was sought.

Results

No significant difference was observed in the radiographs between the measurement of the remaining dentin thickness before and after the excavation of caries. In contrast, the radiographic measurements of remaining dentin thickness were underestimated by an average of 20% compared with those made with macrophotographs.

Limitations

Interpretation of radiographs varies from one practitioner to another and is a function of the operator’s visual acuity.

Conclusion

Measuring the residual dentin thickness on a radiograph underestimates the actual thickness by about 20%. Further studies are needed to confirm these results.

Clinical significance

Our results indicate that remaining dentin thickness is greater in reality than is shown on a radiograph. This information can help clinicians to refine their diagnoses and treatment plans.

How to cite this article: Berbari R, Khairallah A, Kazan HF, Ezzedine M, Bandon D, Sfeir E. Measurement Reliability of the Remaining Dentin Thickness below Deep Carious Lesions in Primary Molars. Int J Clin Pediatr Dent 2018;11(1):23-28.

In vitro investigation of the cleaning efficacy, shaping ability, preparation time and file deformation of continuous rotary, reciprocating rotary and manual instrumentations in primary molars

Background. Efficient canal preparation is the key to successful root canal treatment. This study aimed to assess the cleaning and shaping ability, preparation time and file deformation of rotary, reciprocating and manual instrumentation in canal preparation of primary molars.

Methods. The mesiobuccal canals of 64 extracted primary mandibular second molars were injected with India ink. The samples were randomly divided into one control and three experimental groups. Experimental groups were instrumented with K-file, Mtwo in continuous rotation and Reciproc in reciprocating motion, respectively. The control group received no treatment. The files were discarded after four applications. Shaping ability was evaluated using CBCT. After clearing, ink removal was scored. Preparation time and file fracture or deformation was also recorded. Data were analyzed with SPSS 19 using chi-squared, Fisher’s exact test, Kruskal-Wallis and post hoc tests at a significance level of 0.05.

Results. Considering cleanliness, at coronal third Reciproc was better than K-file (P < 0.001), but not more effective than Mtwo (P = 0.080). Furthermore, Mtwo leaved the canal cleaner than K-file (P = 0.001). In the middle third, only Reciproc exhibited better cleaning efficacy than K-file (P = 0.005). In the apical third, no difference was detected between the groups (P = 0.794). Regarding shaping ability, no differences were found between Reciproc and Mtwo (P = 1.00). Meanwhile, both displayed better shaping efficacy than K-file (P < 0.05). Between each two groups, there were differences in preparation time (P < 0.05), with Reciproc being the fastest. No file failure occurred.

Conclusion. Fast and sufficient cleaning and shaping could be achieved with Mtwo and especially with Reciproc.