Micro-computed tomography (micro-CT) evaluation of root canal morphology in immature maxillary third molars

The endodontic treatment of immature permanent teeth with necrotic pulp is a significant clinical challenge. The success of regenerative endodontic procedure is highly dependent on disinfection of the root canal and an accurate anatomical knowledge of the root canal. The aim of this study was to use micro-computed tomography (micro-CT) analysis to investigate the configuration of root canals in the upper permanent third maxillary molars with incomplete root development in their coronal, apical and middle third portions. Thirty immature third permanent maxillary molars were scanned using a micro-CT system. Then, we measured the diameters and areas of the root canal in the coronal, middle and apical third of the roots. The ratio between the long and short diameter of each root canal was then calculated and the canals were divided into several groups: round, oval, long oval, flat and irregular. The round configuration was not observed in the distobuccal and mesiobuccal roots in any of their anatomical regions. Oval and long oval canals predominated in the distobuccal root. The greatest variations were observed in the mesiobuccal root, with the ribbon-shaped canal predominating in the middle region and an irregular shape in the apical region. In the coronal region of the palatal canal, the round configuration predominated; in the middle third, we observed an almost equivalent distribution between round and oval configurations; apically, the oval shape predominated. In conclusion, we observed significant complexity and variation in the morphology and configuration of root canals in immature permanent molars, thus generating additional obstacles for the success of regenerative endodontics.

Regenerative endodontic treatment of immature permanent teeth after mechanical instrumentation with XP-Endo Finisher

INTRODUCTION

The traditional treatment of immature permanent teeth with necrotic pulp involves creating an apical barrier by using calcium hydroxide or an MTA plug for an extended period of time. A novel therapeutic approach called regenerative endodontic procedures (REP) is used to allow root development to continue.

COMPARATIVE EVALUATION OF THE EFFECTIVENESS OF DIFFERENT METHODS FOR THE CARIES-DIAGNOSIS OF OCCLUSAL SURFACES OF THE FIRST PERMANENT MOLARS

Aim: Comparative evaluation of the diagnostics of the occlusal surface between light-induced fluorescence (SoproLife camera) and the accepted international system for the diagnosis of caries ICDAS II. Materials and methods: 150 first permanent molars were examined in 50 patients in the age group 6-9 years. The results from the studied occlusal surfaces by light fluorescence (SoproLife "day light" and "blue light" 405 nm) and direct visual observation (ICDAS II codes) were compared using a correlation coefficient. Results: A high identity is reported between the two diagnostic methods - correlation coefficient= 0.97 (using Spearman's rank correlation). Conclusion: SoproLife camera eliminates the risk of "overdiagnosis", it is a comparable and reliable method for the detection of initial occlusal carious lesions. Both methods show identical advantages in terms of their diagnostic effectiveness in initial occlusal carious lesions.

Seroprevalence of Actinobacillus pleuropneumoniae infection in pigs from Bulgaria

Actinobacillus pleuropneumoniae (App) is the etiological agent of porcine pleuropneumonia. The purpose of the study was to present a serological report on App prevalence among pigs in industrial farms in Bulgaria. Seventy-two pigs from four industrial farms in four districts of Bulgaria – Eastern Bulgaria (Razgrad and Yambol districts) and Western Bulgaria (Lovech and Sofia districts) were included. Animals were divided in two age groups: weaners and fattening pigs. A commercial enzyme-linked immunosorbent assay (ELISA, INgezim APP MIX, Eurofins Ingenasa, Madrid, Spain) for the detection of antibodies against App parasuis in porcine serum was used. Microtitrе plate was coated with App antigen of the serovars 1, 2, 9 and 11. Positive results for anti-App antibodies were detected in 32 (44.4%) of all 72 tested sera. The overall seropositivity in weaners and fattening pigs was 22.2% (8/36), and 66.7% (24/36), respectively. The highest App seropositivity in pigs was found in Eastern Bulgaria - 61.1% (22/36; P<0.001) in comparison to App seropositivity in Western Bulgaria – 27.8% (10/36; P=0.137). This study on anti-App prevalence among pigs in Bulgaria gives new insights on App epidemiology in our country.

Application of Contemporary Magnifying Methods in the Diagnostics of Occlusal Carious Lesions on First Permanent Molars in Children

INTRODUCTION

Dental operating microscopes (DOM) enable dentists to examine, with the aid of magnification and photodocumentation in clinical conditions, the occlusal anatomy of newly erupted permanent molars and to detect any early carious lesions more precisely.

AIM

To determine the advantages of magnifying technology in detecting early occlusal carious lesions in newly erupted permanent first molars.

MATERIALS AND METHODS

We examined 176 first molars of 44 children divided into two age groups: 7-8 and 9-10 years. The surfaces of each of the teeth were examined after they were cleaned with a brush without paste. The diagnoses were first made using only illumination and a clinical examination. These were followed by a visual examination of the occlusal surface using a DOM at ×8 magnification. A photo of the occlusal surface was then taken with a camera at the respective magnification for the purposes of photodocumentation.

RESULTS

This study demonstrated that dental operating microscopes increased by 7% the rate of successful detection of early caries lesions on the occlusal surfaces. There was also a significant increase of the number of diagnosed cavitated caries in the dentine in comparison with those detected with naked eye. Using DOMs in pediatric dentistry facilitates the more detailed and precise diagnosing of early stage carious lesions and/or cavitations in the fissures.

CONCLUSION

The use of a DOM facilitates differential diagnosing between deep fissures and early carious lesions, which is a key point in the assessment of occlusal surfaces of newly erupted permanent molars, necessary for their preventative sealing and micro-invasive treatment.

Comparative Analysis of Root Dentin Loss when Using Modern Mechanical Cleaning Instruments in Immature Permanent Teeth

INTRODUCTION

The full decontamination and disinfection of the root canal system is essential for the success of regenerative endodontic procedures. The current literature does not have information regarding mechanical cleaning of immature teeth with contemporary endodontic instuments.

AIM

To compare the thickness and volume of the dentin removed from the roots of immature teeth after endodontic preparation using XP-endo Finisher, GentleFile Brush and a standard H-file scraping technique through micro-computed tomography.

METHODS

The study included 51 immature permanent molars. Endodontic access was prepared and without performing preliminary extirpation of the pulp, the teeth were divided into three groups. The first group of teeth were instrumented for two minutes with XP-endo Finisher, the second - two minutes with Gentlefile Brush, in the third group the root canals walls were scraped with a No. 40 H-file. The thickness and the volume of the removed dentin was assessed using micro-CT imaging before and after the use of the instruments.

RESULTS

There is no statistically significant difference in the mean values of thickness of dentin removed between the teeth, prepared with XP-endo finisher and Gentlefile Brush. When comparing the mean values of volume of dentin removed between the separate groups, a statistically significant difference was discovered for every compared pair with the highest volume of removed dentin in the group prepared with a hand instrument.

CONCLUSION

The endodontic systems tested when used in immature permanent teeth remove significantly less quantity of hard dental structures compared to a hand file for scraping the root canal.

CONSERVATIVE TREATMENT OF A TOOTH WITH INCOMPLETE ROOT DEVELOPMENT AND A LARGE PERIAPICAL LESION - A CASE REPORT

Background: Regenerative endodontic procedures have become increasingly popular in recent years. This paper reports the use of regenerative endodontics in the treatment of a large cyst-like inflammatory periapical lesion in an immature permanent tooth. Case report: A 12-year-old boy with a submucosal abscess in the upper jaw visited the Department of Pediatric Dentistry. Previous injury in the area was reported. The X-ray showed a well-defined large osteolytic lesion engaging the apical part of the root. The initial treatment plan included creation of MTA plug and apical surgery. Throughout the treatment course, the patient skipped his appointments and returned 8 months later. The initial working length couldn't be reached, and a hard barrier was present in the middle portion of the root canal. The CBCT showed that the size of the lesion had decreased significantly. Bone-like tissue with a density similar to surrounding spongiosis was observed in the root canal. There was no change in the contour and length of the root walls. Conclusion: Regenerative endodontics could be successfully used in the treatment of some immature permanent with necrotic pulp and large periapical lesions.

STUDY ON THE EFFECTIVENESS OF INTRACISTERNAL ANTIBIOTIC TREATMENT FOR THE CONTROL OF MASTITIS IN GOATS

The aim of this study is to investigate the healing and prophylactic effect of drying-off antibiotic therapy using the selective and non-selective approach of administration of the antibiotics. First experimental group at the start of the dry period were treated non-selectively (all halves) intra-cisternally with antibiotics. In the second group, we only treated those halves that were diagnosed with subclinical mastitis. The control group of 9 goats was not treated. The number of somatic cells in treated groups after birth decreased from 2586 x 10³/ mL to 560 x 10³/mL in the first group and from 1978 x 10³/mL to 526 x 10³/mL in the second. Post partum, 10% of the halves were found to have subclinical mastitis. A healing effect was achieved in 25% (n=5) milk halves. New intramammary infections developed during the dry period also occurred in 5% (n=1) of the milk halves. In the second post-partum study, subclinical mastitis was observed only in 5% (n=1). Healing was achieved in 30% (n = 6) and the new intramammary infections (NIMIs) were 10% (n=2). In the control group, healing was only observed in 5% (n=1) and NIMI were 27.78% (n=5). The application of both treatment approaches, results in reduction in prevalence and manifestation of mastitis, as well as reduction of somatic cells in milk after kidding. The selective treatment method may be preferred, in order to reduce the cost of medications in conducting treatment and prophylaxis programs.