Comparative evaluation of change in root canal shape and area in primary molars using ProTaper and K3 rotary systems: In vitro study.

BACKGROUND: Rotary instrument techniques have shown evidence of simultaneously enlarging the root canal and maintaining the canal anatomy. Protocols for the use of rotary systems in primary molars are not well established. AIMS: The aim of the study was to evaluate and compare root canal shape and area after ProTaper and K3 rotary instrumentation in primary molars. SETTINGS AND DESIGN: Coronal access cavities with straight-line access into the root canals were prepared on primary mandibular molar teeth, extracted for therapeutic reasons. The teeth were aligned in a prefabricated template in individual self-cure acrylic blocks such that their respective positions could be reproduced later. SUBJECT AND METHODS: Forty-two primary mandibular molar teeth selected were equally divided into three groups: instruments with stainless-steel (SS) hand K-files, ProTaper, and K3 Endo rotary system. Precomputed tomography (CT) slices were taken at predetermined levels (coronal, middle, and apical third) followed by instrumentation of canals using selected files and post-CT scan. STATISTICAL ANALYSIS USED: Data obtained were evaluated using independent t-test with a 0.05 level of significance and ANOVA. RESULTS: SS hand K-files and rotary ProTaper and K3 Endo of 0.04 taper produced a predominantly round shape at coronal, middle, and apical levels. ProTaper system caused the greatest increase in round-shaped canals and canal area followed by K3 Endo of 0.04 taper. CONCLUSIONS: Shaping abilities of both manual and rotary instrumentation systems in primary molars were similar, whereas for enlarging and maintaining anatomy, rotary systems (ProTaper and K3) were better.

Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars.

UNLABELLED: Need for the study: The most important procedure for a successful endodontic treatment is the cleaning and shaping of the canal system. Understanding the internal anatomy of teeth provides valuable information to the clinician that would help him achieve higher clinical success during endodontic therapy. AIMS: To evaluate by computed tomography-the internal anatomy of mandibular second primary molars with respect to the number of canals, cross-sectional shape of canals, cross-sectional area of canals and the root dentin thickness. MATERIALS AND METHODS: A total of 31 mandibular second primary molars were subjected to computed-tomographic evaluation in the transverse plane, after mounting them in a prefabricated template. The images, thus, obtained were analyzed using De-winter Bio-wizard® software. RESULTS: All the samples demonstrated two canals in the mesial root, while majority of the samples (65.48%) demonstrated two canals in the distal root. The cross-sectional images of the mesial canals demonstrated a round shape, while the distal canals demonstrated an irregular shape. The root dentin thickness was highly reduced on the distal aspect of mesial and mesial aspect of distal canals. CONCLUSION: The mandibular second primary molars demonstrated wide variation and complexities in their internal anatomy. A thorough understanding of the complexity of the root canal system is essential for understanding the principles and problems of shaping and cleaning, determining the apical limits and dimensions of canal preparations, and for performing successful endodontic procedures. How to cite this article: Kurthukoti AJ, Sharma P, Swamy DF, Shashidara R, Swamy EB. Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars. Int J Clin Pediatr Dent 2015;8(3):202-207.

Fracture resistance of endodontically treated permanent anterior teeth restored with three different esthetic post systems: An in vitro study.

BACKGROUND: Esthetic coronal reconstruction of fractured anterior teeth is often performed using intra radicular posts. Most of the commonly used commercially esthetic post systems do not exhibit similar physical properties as dentin resulting in failures. AIM: To evaluate and compare the fracture resistance and mode of failure of simulated traumatized permanent central incisors restored with three different post systems including biologic dentin posts. MATERIALS AND METHODS: A total of 40 recently extracted human maxillary central incisors with similar dimensions were decoronated 2 mm above the cemento-enamel junction and endodontically treated. Ten specimens were randomly selected as the Group I - Control group (core built teeth without intraradicular posts). The remaining 30 teeth were equally divided and restored with zirconia (Group II, n = 10), fiber re-inforced composite (FRC) (Group III, n = 10) and biologic dentin posts (Group IV, n = 10) using resin bonded cement and their cores built-up. These samples were embedded in acrylic resin and then secured in a Universal Testing Machine and subjected to fracture resistance testing. The location of failure in the specimens was evaluated using a stereomicroscope. RESULTS: Intergroup comparison revealed that the control group and zirconia post group (522 ± 110 N) demonstrated the least fracture resistance, while dentin post group (721 ± 127 N) the highest. There was no statistically significant difference between fiber post and dentin post groups. Fractures that were repairable were observed in fiber post and dentin post groups, whereas mostly unrestorable, catastrophic fractures were observed in the zirconia post group. CONCLUSION: Teeth restored with the biologic dentin post system demonstrated the highest fracture resistance and repairable fractures, closely followed by FRC post system. The least fracture resistance and most catastrophic fractures were demonstrated by the zirconia post system.

Juvenile recurrent parotitis in children: diagnosis and treatment using sialography.

Juvenile recurrent parotitis (JRP) is a nonobstructive, nonsuppurative parotid inflammation in young children. Causative factors are many such as allergy, infection, local autoimmune manifestations, and genetic inheritance have been suggested, but none have been proved. Parotid sialography is a hallmark in the diagnosis of JRP but newer modalities such as ultrasonography, computed tomography and magnetic resonance imaging-sialography are noninvasive investigative techniques. Recurrent attacks are often managed conservatively. Here we report a case of a 5-year-old child with JRP. Sailography can be used as both diagnostic and therapeutic modality.

Cariogenicity and acidogenicity of human milk, plain and sweetened bovine milk: an in vitro study.

UNLABELLED: The objective of the present study was to determine the acidogenicity and cariogenicity of human breast milk and plain and sweetened packaged bovine milk. STUDY DESIGN: First all milk specimens were inoculated with a cariogenic strain of Streptococcus mutans (SM). The culture pH and number of colony forming units (cfus) was assessed. Second, the buffer capacity of all milk specimens was evaluated by mixing with acid. Finally, enamel windows were created on extracted primary maxillary incisors and colonized with SM. Enamel demineralization and caries progression were assessed visually, histologically, and radiographically at the end of twelve weeks. RESULTS: Plain and sweetened packaged bovine milk (BM) supported greater bacterial growth and caused more fermentation than human breast milk (HBM). The buffer capacity values for plain and sweetened bovine milk were highest; HBM, however had poor buffering capacity. The progression of the carious lesions into the dentin was most severe for the sweetened bovine milk. CONCLUSIONS: HBM and plain bovine milk are relatively cariogenic in an in vitro caries model in the absence of saliva. However, supplementation with sugar exponentially enhances the cariogenic potential of the natural milk.

Leaching of ions from materials used in alternative restorative technique under neutral and acidic conditions: a comparative evaluation.

This study was undertaken to gain an insight into the interaction of conventional glass ionomers (GC Fuji II, GC Fuji IX GP and Chem Flex restorative materials) commonly used in Alternative Restorative Technique (ART) with aqueous solutions in terms of water sorption, solution buffering and ion release. Both immature and mature specimens of all materials evaluated, showed a substantial increase in mass, pH and release of Na, Ca, Sr, Al, Si, P and F following immersion in deionized water lactic acid (pH 2.7) and lactic acid (pH 5.2). However the ion release profiles were found to be greater in acidic media (Lactic Acid pH 2.7 > Lactic Acid pH 5.2) than in deionized water.

Dental crowding in primary dentition and its relationship to arch and crown dimensions among preschool children of Davangere.

The purpose of the present study was to evaluate dental crowding in the deciduous dentition and its relationship to the crown and the arch dimensions among preschool children of Davangere. Stratified randomized selection of one hundred, 3-4 year old healthy children with all primary teeth erupted was done and divided into two groups. One group had children with anterior crowding in both the arches while the other had spacing. Alginate impressions of the upper and lower arches were made and the study casts were obtained. The tooth and arch dimensions were determined. Mesiodistal dimensions of all the teeth were significantly larger in the crowded arch group. However, the buccolingual dimensions of the maxillary right central incisor, mandibular lateral incisors and the maxillary molars and the crown shape ratio of maxillary lateral incisors, mandibular canines and mandibular right second molar was statistically different. No significant correlation was found between the arch width and the presence of crowding of deciduous dentition. The arch depth of the spaced dentition was greater when compared to the crowded ones. The arch perimeter of the crowded arches was significantly less than the spaced arches.

Evaluation of the clinical behavior of resin modified glass ionomer cement on primary molars: a comparative one-year study.

AIM: The objectives of the present study were to evaluate and compare the clinical behavior of resin modified glass ionomer cement (RMGIC) on primary molars with conventional and modified cavity preparations. METHODS AND MATERIALS: Forty-two children, 5-9 years of age, having bilateral initial occlusal caries on the mandibular primary second molars were selected for the study. A split mouth design was employed where conventional Class I cavities with a 90 degrees cavosurface angle were prepared randomly on primary second molars on one side and modified cavities with a 1 mm straight bevel along the cavosurface margin on the contra-lateral side. These cavities were restored with RMGIC. The restorations were evaluated during subsequent visits, for a period of one year. RESULTS: At the end of one year, 90% of the restorations survived in the conventional cavity group whereas 100% of the restorations survived in the modified cavity group. CONCLUSION: Incorporation of a bevel in Class I cavities increases the survival rate of RMGIC restorations. There was no significant difference in the clinical behavior between the two groups. However, beveling does contribute to long term clinical success of these restorations. CLINICAL SIGNIFICANCE: Incorporation of a straight bevel in conventional cavities will improve the retention of RMGIC by increasing the bonding area and enhancing the desired properties of the material.