11. A SURVEY OF TECHNIQUES AND DIFFICULTIES IN ANESTHESIA OF MANDIBULAR MOLARS WITH IRREVERSIBLE PULPITIS

E. Simeonova1, S. Canova1, P. Zagorchev2, S. Dimitrova1, N. Mussurlieva3

1MU- Plovdiv, Faculty of Dental Medicine, Department of Operative Dentistry and Endodontics

2MU- Plovdiv, Faculty of Pharmacy, Department of Medical Physics, Biophysics and Mathematics

3MU- Plovdiv, Faculty of Public Health, Department of Social Medicine and Public Health

The achieving of adequate pulpal anesthesia of mandibular molars with irreversible pulpitis is a challenge for the dentist.

Aim: The aim of the questionnaire is to explore those used in dental practice methods and difficulties in anesthesia of mandibular molars with irreversible pulpits and the use of alternative techniques of anesthesia.

Material and methods: A survey containing 11 questions, of which 2 are multiple choice questions, was distributed among 143 dentist, aged between 26 and 76, with different situated dental practice, during scientific conferences held in the country.

Results: About 60% of respondents use inferior alveolar nerve block in combination with additional anesthesia (intraligamentary or intrapulpal injection) during endodontic treatment of irreversible pulpitis of mandibular molars. Approximately 45% of respondents cited that the disadvantages of the inferior alveolar nerve block is the lack of effectiveness in achieving adequate anesthesia. About 40% of respondents are not familiar with the technique and systems for intraosseous anesthesia as an alternative method of anesthesia due to lack of promotion.

Conclusions: The inefficiencies of inferior alveolar nerve block requires the use of additional techniques of anesthesia. Intraosseous anesthesia is not preferred and used method of pain relief due to lack of sufficient awareness and doubt its effectiveness.

Keywords: survey, inferior alveolar nerve block, intraosseous anesthesia

12. SURVEY INVESTIGATION ON METHODS, AGENTS AND DIFFICULTIES IN OBTURATION OF THE ROOT CANAL SYSTEM

E. Boyadzhieva1, S. Dimitrova1, N. Musurlieva2

1Medical University Plovdiv, Faculty of Dental Medicine, Department of Operative Dentistry and Endodontics

2Medical University Plovdiv, Faculty of Public Health, Department of Social Medicine and Public Health

The complex anatomy of the root canal system (RCS) creates difficulties in its cleaning and 3D obturation, which is a prerequisite for a number of failures of endodontic treatment.

Aim: This study aims to establish the methods and means of obturation of the RCS, as well as problems related to their use in dental practice.

Materials and methods: An anonymous survey among 157 dentists (LDM) with different age, seniority and location of practice. The questionnaire includes 15 questions, respondents express opinion about the frequency of endodontic treatment difficulties, methods and means of obturation of the RCS.

Results: 30% of respondents held endodontic treatment every day. More than half of respondents state that complex root canal anatomy is the greatest difficulty in processing and obturation of the RCS, the “root canal filling paste with / without gutapercha point” is indicated from more than 60 percent as the most frequently used method of obturation of the RCS and zinc oxide eugenol and formalin-rezortsin root canal filling pastes are still cited by the highest percentage of respondents. 80% of respondents indicate that they need more information about obturation of the RCS.

Conclusions: The results show that the complex clinical and anatomic situation creates difficulties in obturation of the RCS, but most dental practitioners use established in the years methods and means for its obturation.

Keywords: obturation, root canal system, survey

13. PROPORTIONS OF FRONTAL TEETH IN NATURAL PERMANENT DENTITION-RESEARCH ON GYPSUM MODELS

G. Iliev*, J. Pavlova**, D. Filtchev**, S. Rangelov***, B. Kocheva***, M. Dimova***, S. Nasif- Makki***, A. Filtchev****

*Assistant Professor, Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Sofia

** Associate Professor, Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University of Sofia

*** Students of IV year, Faculty of Dental Medicine, Medical University of Sofia

**** Professor, Director of Department of Prosthetic Dentistry, Dean of Faculty of Dental Medicine, Medical University of Sofia

Aim: To determine the proportion prevailing in the natural dentition and to define the types of dominance, by examine the interrelation between widths, heights and areas of the upper frontal teeth on plaster models.

Materials: 61 students at the Faculty of Dental Medicine, Medical University of Sofia, 27 male, 34 female, aged 18 to 30, were examinated, all of them with natural dentition, without gingival recessions or orthodontic disorders in the frontal area. 122 segments of the upper jaw, left and right, were measured.

Methods: Impressions were taken from the upper jaw of every participant using fabric trays and alginate. Plaster models (Class III) were prepared. On every frontal tooth of the models, with fine- tipped pen (0.3 mm), following points were marked: mesial and distal angle and the cervical zenyth of the tooth. From the zenyth to the incisal edge, respectively to the cusp of the canine, a perpendicular line was lowered. Measurements were made by a digital calliper- gauge. The areas of the teeth were calculated.

Results: The interrelations between widths, heights and areas of the upper frontal teeth were determined. Three types of dominance in natural dentition were established: high, medium and low; their characteristics and average parameters were determined, separately for women and men.

Conclusion: Medium (Norm) dominance is most characteristic of natural dentition with proportional ratio between central incisors: lateral incisors: canines as follows:

  • Women: Widths: 1,28:1:1,14; Hights: 1,17:1:1,12; Areas: 1,48:1:1,29

  • Men: Widths: 1,33:1:1,17; Hights: 1,17:1:1,15; Areas: 1,57:1:1,36

Keywords: upper frontal teeth, dominance, proportions

14. EXTERNAL ROOT RESORPTION – CASE REPORT

Ts. Tsvetanov

Medical University Plovdiv, Bulgaria,

Department of Oral Surgery, Dental Faculty

Еxternal root resorption is a rarely clinical phenomenon, localized on various outer root surfaces, followed by resorption of lamina dura and alveolar bone. Еxternal root resorption can lead to degeneration of dental cementum and dentine. According to literature dates prevails in the upper jaw and molars. The most common localization of resorption is root apex. According to age, the most frequent resorption is in aged between 21 and 30 years. According to gender, the more common is among the female population. Clinical symptoms are pain, swelling and mobility of the tooth. Occur following stimuli such as infection, pressure, trauma or orthodontic tooth movement.

Case presentation: A 45 year old male patient with a chief complaint of slowly progressing swelling on the left side of the maxilla approximately 0.5×0.5 cm in size since 1 week. Intraoral examination revealed well-defined localized swelling (soft, fluctuant, and tender on palpation) in the region of 24. Radiological examination revealed a upper first premolar with external root resorption and localized periodontitis. The maxillary first premolar was extracted by using a mucoperiosteal flap.

Results and discussion: In the postoperative period we did not observe any swelling or pain in the area intervened. The healing took place within a week without any complications.

Conclusion: Presented case report illustrates a rare case of external root resorption around maxillary first premolar. To conclude radiological examination is necessary to provide an adequate diagnosis and treatment.

Keywords: dental radiography, diagnosis, root resorption, treatment

15. LASER PHOTODYNAMIC THERAPY FOR RESTORING THE GINGIVAL TISSUES AFTER PREPARATION

R. Kazakova*, A. Vlahova*, Chr. Kissov*, G. Tomov**, T. Bozhkova*

*Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University – Plovdiv

**Department of Periodontology and Oral Mucosal Diseases, Faculty of Dental Medicine, Medical University – Plovdiv

Taking a precise impression is critical to the success and accuracy of the prosthetic restorations. The presence of swollen and inflamed gingival tissue compromises dryness of the prosthetic field and the accuracy of future impression. Laser photodynamic therapy is a new method for restoring the affected or inflamed gingival tissues after preparation in order to take a maximum precise impression.

Aim: The aim of this study is to demonstrate laser photodynamic therapy as a method of healing of gingival tissue prior to impression taking.

Methods and materials: In order to accelerate the healing of the gingival tissues, laser photodynamic therapy with a diode laser FOX (A.R.C. Lasers) and a photo activator EmunDo (Indocyanine Green) is applied twice. The procedure is performed in a therapeutic pulse mode with 200 mW, with a non-initiated fiber and exposure duration 30 seconds per tooth.

Results: Photodynamic laser therapy provides good healing, as well as a bio stimulating and regenerating effect. The dye affects only the damaged tissues and pathogens without harming the healthy ones.

Conclusion: Photodynamic therapy has a favorable healing effect on the gingival tissues. The advantage is the short exposure time, incessant control by the dentist, as well as the fast action.

Keywords: EmunDo, Indocyanine Green, Laser Photodynamic Therapy

16. SPECIAL FEATURES OF INTERJAWS RELASHIONSHIPS REGISTRATION IN CAD/CAM FPDs FABRICATION

V. Hadzhigaev, A. Vlahova, St. Zlatev, G. Todorov, Chr. Kissov

Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University –Plovdiv

Proper fixation of the occlusion in the design of CAD/CAM fixed restorations is essential for their optimal function in terms of the oral cavity.

Aim: The aim of this presentation is to provide information about some special features of interjaws relationships registration in fixed partial dentures (FPDs) fabrication by CAD / CAM technology.

Materials and methods: Intraoral occlusal scanning in patients which teeth are prepared for abutments (on one side or on both sides of the dental arch) is closely connected with the opportunity of improper bite registration. The use of a full arch digital impression and the laboratory scanning of plaster models fixed by a silicone key – bite registration are the basic methods applied for accurate interjaws relationships registration.

Results and discussion: Intraoral scanning has a number of features regarding the specifics of taking a snapshot and carries the risk of formation of artifacts and gaps (non-shot sections) in the digital impression. The absence of a distal abutment tooth support further impedes the interjaws relationships fixation. This can lead to the construction of a restoration with greater occlusal thickness and establishing preliminary contacts, or vice versa, a restoration with less occlusal thickness and perforation during the milling process. The use of the method of the full arch digital impressions ensures accurate interjaws relationships registration by bilateral bite scanning. The other method of the laboratory scanning of plaster models fixed by a silicone key – bite registration, taken from the patient’s mouth, is an alternative to the intraoral optical impression.

Conclusion: Knowledge about the capabilities of intraoral and laboratory scanning in the CAD / CAM technology creates options for an individual approach aimed to optimal interjaws relationships registration.

Keywords: fixation, interjaws relationships, CAD/CAM fixed partial dentures

17. VISUALIZING POTENTIAL OF HUMAN MEMORY

D.Shopova*, Chr. Kissov**, R. Kazakova*, T. Bozhkova*, M. Hristozova*

Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University Plovdiv

* Assistant Professors in Department of Prosthetic Dentistry

**Professor in Department of Prosthetic Dentistry

Human memory has infinite capabilities. The ability and the way of memorizing information are individual -a scientific text, mathematical formulas, chemical formulas, etc. There are many scientific methods and approaches to qualitative and quantitative determination of this indefinable potential.

Aim: Using a six-point scale of assessment to mark the level of memorizing certain information and the level of forgetfulness after a fixed period of time.

Materials and methods: The study involved 87 dental students from the 1 course, Bulgarian and English education. They received a short text (650 words) and preparation time 30 minutes. The results were produced by a specially developed computer program. The test is applied again after a period of two weeks, the student was tested on the same questions, but the sequence and places of answers were changed.

Results: At the end of the test, each student receives the following information: a realistic assessment of their knowledge; a self-assessment of their knowledge and recommended number of hours of self-preparation for passing the exam.

Conclusion: The computer program gives good information about the mental abilities of students, and it has a motivational effect after re-testing with decreased result.

Keywords: memory, computer program

18. CORRECTION OF DENTAL CLASS II/2 ANGLE WITH MYOBRACETM SYSTEM

N. Ivanova1, M. Dinkova2

1 MMD Dental Center of Orthodontics, Sofia

2 Department of Orthodontics, FDM, MU- Sofia

Class II/2 Angle malocclusion is characterized by combination of deep bite, retroclined incisors and distal occlusion in the lateral segments.

Aim: The aim of the current study is to follow the correction of dental Class II/2 Angle in patient with skeletal class I malocclusion, treated with Myobrace TM system.

Materials and methods: Boy, 10-year-old, with early mixed dentition, dental Class II/2, skeletal class I malocclusion and hypodivergent pattern of growth. After the full orthodontic analysis was made, a treatment with Myobrace myofunctional appliances was started. The treatment progress included preliminary Trainer for Adults (T4A) appliance for 11 months and Myobrace (MB) appliance for 13 months – active wearing (every night and 1 to 4 hours during the day). After that a passive wearing regime of MB appliance was recommended (2 times weakly) until the permanent dentition is formed.

Results: In the 5-year follow-up period a correction of Class II/2 Angle malocclusion and deep bite was established. The tooth arches and facial profile of the patient were harmonized. A stable result without fixed retainer application was achieved. The function and aesthetics of the patient were improved.

Conclusion: Myofunctional appliances of MyobraceTM system are successfully applied for treatment of dental Class II/2 Angle in patients with skeletal class I malocclusion and early mixed dentition.

Keywords: MyobraceTM, Class II2 Angle, deep bite

19. APICAL MICROLEAKAGE OF FOUR MATERIALS AFTER ROOT END RESECTION (IN VITRO STUDY)

E. Radeva*, Ts. Uzunov*, I. Ivanov**, G. Genchev***

* Department of Conservative Dentistry, Faculty of Dental Medicine, MU Sofia

**Dentist

***Department of Health Economics, Faculty of Public Health, MU Sofia

Hermetic sealing of the apical area after root end resection is essential to the success of endodontic surgery.

Aim: Is to compare microleakage after root end resection of the two bioceramic sealers without retrograde filling-Total Fill BC Sealer and MTA Fillapex, and two materials for retrograde filling-MTA and Biodentine, using the method of penetration of dye-2 % methylene blue.

Material and methods: Forty-eight extracted single- rooted human teeth were used in this study. The resection was made at 3 mm from the root tip at an angle of 90 degree to the long axis of the tooth. The teeth were divided into 4 groups: 1st group (n=9) – root canal obturation with Total Fill BC Sealer without retrograde filling. 2nd group (n=8)-root canal obturation with MTA Fillapex without retrograde filling. 3rd group (n=10)–retrograde ultrasonic cavity preparation and filling with MTA. 4th group (n=8)-retrograde ultrasonic cavity preparation and filling with Biodentine. The outer surface of the root is covered with two layers of varnish, with the exception of the apical 3 mm then immersed in 2% methylene blue for 72 h. The degree of penetration of the dye is measured in millimeters. The data was entered and processed with the statistical package IBM SPSS Statistics 22.0. We reject the null hypothesis when p<0.05.

Results: With significantly higher value is the arithmetic mean of the group with the root canal obturation with Total Fill BC Sealer without retrograde filling – 2,01 mm; versus a retrograde filling with MTA-0,68 mm and Biodentin-0,51 mm; and no statistically significant difference with the group root canal obturation with MTA Fillapex – 1,76 mm.

Conclusion: In the four material microleakage dye was observed, but to varying degrees.

This study was supported by Medical University – Sofia, contract № 45/2015

Keywords: apical microleakage, Total Fill BC Sealer, MTA Fillapex, Biodentine, MTA

20. Compliance knowledge to children and parents about oral hygiene and nutrition

P. Bakardjiev, M. Peneva


Department of Pediatric Dentistry, Faculty of Dental Medicine, Medical University – Sofia

Oral hygiene and nutrition are two main components of the programs for oral health promotion. The creation of such a program requires a basic assessment of existing knowledge in the study group. Knowledge of children in the age 4-6 are formed mainly of parental knowledge and forms the basis for the formation of children and oral hygiene and eating habits.


Aim: The aim of this study is to compare the knowledge of parents and children about oral hygiene and feeding activity.

Materials and methods: They were examined 150 children, divided into three age groups-4, 5 and 6 years from kindergartens in the Sofia city and their parents (150). They were created two types of questionnaires with similar issues for children and parents. Questions are directed to establish knowledge and existing oral hygiene and dietary habits and preferences, and regular visits to the dental office. Comparison was made between parental and children’s knowledge in the study group. They were used alternative analysis and a T-criterion by Student-Fisher.

Results: The frequency, timing and sequence of cleaning gear are directly dependent on the knowledge of the parents. Knowledge resources, duration and food intake following the final cleaning are not depending on parental knowledge; Intermediate feeding is not in connection with parental knowledge. The type of interim food intake and fluid depend on parental knowledge. No link between parental knowledge and visit the child in the dental office.


Conclusions: Parental knowledge in the majority of cases, define the knowledge and behavior of the child.


Keywords: promotion, oral health, children, preschool

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