Conservative dentistry and endodontics

Fusion is defined as two separately forming teeth joined together while gemination refers to partial development of two teeth from a single tooth bud. Fusion may be either complete or incomplete depending on the stage of development. The overall prevalence of the tooth fusion is approximately 0.5% -2-5% in deciduous teeth and 0.1% in permanent dentition. The exact aetiology is not clear, but it is thought that some pressures or physical forces may cause the contact of developing teeth. The case report presented here highlights a case of fusion between permanent mandibular central incisor with lateral incisor in a male patient.

ABSTRACT : The root canal system is an arborizational, anastomotic, byzanthine, labyrinthine complexity, morphologically comparable to a mosaic. While primary canals exist, the tributaries, accessory branches and lumina of dentinal tubules harbour extensive tissue and microflora which if left untreated remains vector for persistent and refractory pathology. Therefore root canal  shaping and cleaning is of utmost importance in the success of root canal treatment. Number of systems are available for effective shaping accounting from hand files to nickel titanium rotary files to the new single file concept “WAVE ONE” KEYWORDS : Wave One, Reciprocating Motion, Nickel Titanium, Reverse  Balanced Force Technique, vCJD
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Complicated crown fractures that involve more than 50% tooth loss and with the fracture line extending subgingivally are of great concern to the dentist. The final restoration should be aimed to provide the adequate retention without compromising the esthetics. So, in this article 2cases were treated with rapid orthodontic extrusion and surgical crown lengthening respectively to preserve and restore the natural tooth structure.

Aim: The aim of this study was to determine the prevalence of dens invaginatus among patients visiting AIMST Dental care centre. Materials and methods: Intra oral periapical radiograph was taken on lateral incisor of 102 patients undergoing treatment in AIMST polyclinics and Oral Surgery clinics. Of the 102 patients 21 patients were Malays, 52 Chinese and 29 were of Indian ethnicity. Results: Dens invaginatus was prevalent in 3 out of 102 patients among the three two were Chinese and was a Indian patient and all three patients exhibited Type 1 type of dens invaginatus. Conclusion: The occurrence of dens invaginatus appears to be prevalent among Chinese and Indian population but further study with higher sample size would help in arriving at conclusive results.

Key words : Demineralization and remineralization begins with historical prespective on caries. Caries were identified as a major public health problem in 1940s. Demineralization is a process of removal of minerals from dental enamel. Remineralization on the other side is the process of restoring minerals to hydroxyapatite lattice. The battle to keep teeth strong and healthy is dependent upon ratio between demineralizaton and remineralization. In this scientific era new advances have changed our idea from "cure" to "prevention". Remineralization can mainly be achieved by mineral or ionic technology .Ionic technology mainly includes fluorides. Fluorides works primarily via topical mechanism which includes ,inhibition of demineralization at crystal surface, enhancement of remineralzation at crystal surface, and at high concentration inhibition of bacterial enzymes. This article deals with various aspects of fluorides in management of De/ Remineralization.

ABSTRACT: Success or failure of endodontic treatment depends, among other parameters, on an accurate determination of the working length. Electronic apex locators (EALs) are a routinely used procedure in endodontic practice; yet their accuracy has been reported to vary from 35%  to 100%. The operating systems of the EALs (frequency or impedance quotient) and different investigative methodologies explain the higher accuracy obtained with the current generation of devices. It is difficult to draw conclusions on the basis of the results obtained with the new generation EALs because of research variables that can influence the results. KEYWORDS: Apex locators, Endodontics, Root apex, Working length
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3D printing generally describes a manufacturing process that creates an object by building one layer at a time adding multiple layers which results in the formation of an object.3D printing can be precisely described as Additive manufacturing or Rapid prototyping. Since the advent of additive manufacturing (AM) or 3D printing as it is commonly known, customization has become a feasible reality.
Dentistry is one avenue in medicine that had greatly benefitted from 3D printing. Creating artificial teeth and dental implants has become all the more easily owing to the ability of the process to create them rapidly, sometimes within a dentist’s office itself.

Introduction: Esthetic restoration is a prime concern for everyone in todays' world. Dentists are in search of a durable and tooth coloured restorative material. All ceramics with high strength are better alternative to composite, amalgam and gold for posterior tooth restoration.

Background: Whether to band molars or bond them during Orthodontic treatment has now become a dilemma to many Orthodontists practicing across the country. Both banding and bonding have their pros and cons.The terminal attachments of fixed appliances are placed on molar teeth; most commonly the first permanent molars. These attachments can take the form of a cemented molar band or a bonded molar tube. The active phase of fixed orthodontic appliance treatment takes an average of two years to complete. To reduce the likelihood of emergency visits, improve patient experience and avoid lengthy treatment times it is important that these attachments have low failure rates.
Aim: This questionnaire based survey aims to evaluate whether orthodontists prefer molar banding or bonding in their routine clinical practice.
Methodology: A sample of 157 participants (orthodontists) was taken after assessing the sample size within the age group of 27 - 50 years of age. The participants comprised of orthodontists practicing in various parts of India. A Questionnaire was created on Google forms and circulated to participants using various social media platforms.The data of responses of participants were analyzed and evaluated with the help of pie charts.
Results: This survey analyzed Orthodontists' choice during banding / bonding of molars and tried to evaluate the common problems faced during either banding molars or bonding them with bondable molar tubes. Majority of Orthodontists preferred bondable molar tubes over banding in routine orthodontic practice. The most common problem faced by majority orthodontists associated with banding was increased chair-side time and increased gingival impingement and irritation, whereas the most common problem faced by them associated with bonding with bondable molar tubes was increased tendency of breakages. Majority of Orthodontists felt that banding in orthodontics was unnecessary as it took up a lot of clinical time and they also asserted that in their experience, frequency of breakages were mostly associated with bondable tubes than bands. However the most striking and highlighting feature of this study was that participants believed that banding molars did not have any added advantage over using bondable molar tubes.
Conclusion: This questionnaire based survey clearly helped in proving that Orthodontists preferred using bondable molar tubes over molar banding in their routine clinical practice as they believed that it saved a lot of clinical time, provided benefits that outweighed its drawbacks and moreover were in no way inferior to molar banding when used during routine fixed orthodontic treatment.

Aim: To evaluate and compare the cytotoxic effects of commercially available root canal irrigant sodium hypochlorite and herbal extracts Turmeric & Neem. Methodology: Sixty samples with 2ml of RBC suspension was randomly assigned to four groups. 3%Sodium hypochlorite, 0.25% Hydro-Alcoholic solution of Turmeric and 7.5% Hydro-Alcoholic solution of Neem and they were tested on RBC suspension. Normal saline was selected as control. Peripheral smear were prepaired to assess the morphological abnormalities of viable cells. After centrifugation of each test tube, the supernated volume was estimated for haemoglobin concentration representing cytotoxicity. Results: Cytotoxicity varies in the following order: 3% Sodium hypochlorite > 0.25% Hydro-Alcoholic solution of Turmeric > 7.5% Hydro-Alcoholic solution of Neem. Results showed that statistically significant difference exists between cytotoxicity of tested irrigating solutions. Conclusion: Considering the undesirable effects of the conventional root canal irrigants, herbal extracts could be an alternative root canal irrigant with least toxicity.

ABSTRACT Background: Ultrasonic irrigation has been proved for its remarkable cleaning efficiency in the field of endodontics. But its role in endodontic re-treatment has been understated. There is not much data available to understand the effect of ultrasonic irrigation for the evaluation of cleanliness of dentinal tubules when it is used with or without chloroform, a gutta percha solvent during endodontic retreatment. Aim: To compare the influence of ultrasonic irrigation with syringe irrigation on cleanliness of dentinal tubules after gutta perch removal for endodontic retreatment with or without the use of chloroform a gutta percha solvent using scanning electron microscope (SEM). Materials  and  Methods: Freshly extracted 45 human mandibular premolar teeth for periodontal and orthodontic reasons were taken and were occlusally adjusted to a working length of 19 mm. The root canals of all teeth were prepared chemo mechanically to a master apical file size 40 and were divided in various groups. In Group 1 (n = 5; control group), the canals remained unfilled. In Groups 2 and 3 (n = 20 each), the canals were filled using lateral compaction with gutta-percha and AH plus sealer, removal of root fillings was undertaken after 2 weeks using Gates Glidden drills and H files without chloroform in Group 2 and with chloroform in group 3. The specimen of Group 2 and 3 were further divided into two subgroups I and
II (n=10). In subgroup I, irrigation was done using side vented needles and sodium hypochlorite. In subgroup II irrigation was done using passive ultrasonic irrigation with sodium hypochlorite. Thereafter, the roots were split and the sections were observed under SEM. The number of occluded dentinal tubules /total number of dentinal tubules were calculated for the coronal, middle and apical third of each root half. Statistical analysis was performed using one-way ANOVA followed by Tukey’s test using standardized technique. Result: Results indicated that the cleanest dentinal tubules were found in the control group (Group 1 where the canals were unfilled) followed by the non chloroform group with ultrasonic irrigation (Group 3 subdivision II) followed by chloroform group with ultrasonic irrigation (Group 2 subdivision II), the non chloroform group with syringe irrigation (Group 3 subdivision I) and least cleanliness was found in the chloroform group with syringe irrigation (Group 2 subdivision I). Conclusion: Under the limitations of this study it could be concluded that both ultrasonic and syringe irrigation showed cleaner canals when chloroform was not used. Irrigation when done with ultrasonics leads to cleaner tubules than syringe irrigation. Hence, mechanical methods of retrieval in conjunction with use of passive ultrasonic irrigation should be a part of retreatment protocol.
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Introduction: To know the effect of surface coating agents on the fluoride release property of conventional Glass Ionomer Cements (GIC) when stored in different storage media.
Materials and Method: Forty-five pellets were fabricated from conventional GIC (GC Fuji type ii capsules) and were randomized into three groups (Group I, II and III)of 15 each. Group I samples were uncoated, group II coated with petroleum jelly and group III were coated with G-coat plus (Nano-filled protective coating). Each group were divided into 3 subgroups consisting of 5 samples which were suspended in each immersion solution in deionized water, artificial saliva and lactic acid and were renewed every 24 hours for 15 days. The fluoride release was measured on day 1st,3rd, 7thand 15thby using UV light visible spectrophotometer.
Results: In deionized water and artificial saliva, for all the 3 groups the mean fluoride release values were found to be fluctuating, as, from 1st day it showed a increased release on 3rd day and subsequently decreased till 15th day where as in lactic acid, it showed a highest release on 1st day and then gradually decreased till 15th day. On intergroup comparison, G-coat plus showed very minimal fluctuation of fluoride release and was statistically significant.
Conclusion: The result concludes that fluoride release from the conventional GIC was reduced with the application of surface coating and maximum fluoride release was observed in low pH environment. Conventional GIC when protected with G-coat plus showed minimal fluctuation in fluoride release, thus allowing sustained release for a longer period of time.

Management of non-vital teeth with open apex is a challenge to dental practitioners. In this scenario, it is difficult to maintain the obturation material within the confines of root canal without encroaching into periapical area. Apexification aims to induce apical closure of the open root apex with hard tissue barrier, against which root filling can be compacted. Also, a thin dentinal wall of canal is matter of concern. Hence, the present case report present the use of MTA to form an apical plug in open apex followed by root canal obturation using thermoplasticized gutta-percha and reinforcement of weekend root with customized fiber post.

Context: Hand washing by a dental health professional before having contact with a patient's oral cavity is considered a fundamental dental clinic infection control measure. Aims: The aim of this study was to evaluate bar soap and liquid soap from dental departments for microbial contamination while it was in use. Settings and Design: This exploratory, cross-sectional study was carried out to identify microorganisms' presence in handwashing with liquid and bar soap at clinical and nonclinical departments in a dental college. Subjects and Methods: In the 2-month study period, all the dental students, dental faculty, and the other auxiliaries present were the participants, and a total of 35 handwashing place samples from 15 different dental departments were collected. The test tube samples of bar soap and liquid soap were all transferred to the microbiology laboratory for microbiological analysis of the samples. Statistical Analysis Used: Data were analyzed using a one-sample ...

The root canal system of mandibular incisors often have three pulp horns and a single root canal, but it has also been demonstrated that there is presence of bifurcated and lateral canals also. The bifurcation of a root canal is the position at which a single canal separates into two smaller canals that follow divergent pathways, in some cases, the canals may re-join to form a single canal again.

Success of endodontic therapy is multi factorial. Starting from good case selection, proper treatment, thorough cleaning and shaping, fluid tight obturation and good seal achieved by post endodontic restoration. One of the reasons for failure of root canal therapy is complex internal anatomy of the teeth which is non-negotiable through orthograde approach. Thorough knowledge of the internal anatomy and its variations is very important to provide the best treatment for the patient. Clinician has to face challenges if there are fused canals, calcified canals, Radix entomolaris, taurodontism and most commonly presence of additional canals. Maxillary third molar is one such tooth where root canal therapy is very difficult to perform not only because of its location in the arch but also due to its varied internal anatomy. The present paper describes variation in the internal anatomy of a maxillary 3rd molar with additional canal and also the importance of magnification in endodontic.

Objectives: The aim of this in vitro study was to compare the efficacy of different irrigating solutions on root canal system and analyzing smear layer using scanning electron microscope (SEM). Materials and Methods: Fifty mandibular premolars were decoronated and split longitudinally. Each root half was divided into five groups (n = 10): Group I ‑ 3 ml of physiological saline, Group II ‑ 3 ml of 2.5% sodium hypochlorite (NaOCl), Group III ‑ 1 ml of 10% citric acid, Group IV ‑ 2% chlorhexidine (CHX) gluconate (Vishal Dentocare, India), Group V ‑ Largal Ultra (ethylenediaminetetraacetic acid [EDTA] 15% + cetrimide 0.75%), Septodont (Saint‑Maur‑des‑fosses, France), and Group VI ‑ Smear Clear (Sybron Endo, Orange, CA, USA) (17% EDTA, cetrimide, and a special surfactant). Irrigation regimens were performed for 1 min. The presence or absence of smear layer at the coronal, middle, and apical portion of each canal were examined under an SEM. Results: A significant difference (P < 0.001) in smear layer removal between smear clear and Largal Ultra at the apical and middle third of the canal was observed. The presence of debris is more obvious in the apical third rather than in the middle and coronal part of the root canals. Conclusion: Largal Ultra, Smear Clear, and the citric acid removed the smear layer more efficient way as compared to CHX, NaOCl, and saline solutions.

Fusion is defined as two separately forming teeth joined together while gemination refers to partial development of two teeth from a single tooth bud. Fusion may be either complete or incomplete depending on the stage of development. The overall prevalence of the tooth fusion is approximately 0.5%-2-5% in deciduous teeth and 0.1% in permanent dentition. The exact aetiology is not clear, but it is thought that some pressures or physical forces may cause the contact of developing teeth. The case report presented here highlights a case of fusion between permanent mandibular central incisor with lateral incisor in a male patient.

During routine dental procedures like root canal treatments, it is unusual that a foreign body gets entrapped or lost in the adjacent soft tissue of the oral cavity. But sometimes due to unexpected movement of the patient or careless handling of the instruments, some instruments may get into the soft tissue surrounding the area of operation. Most of these should be removed immediately to prevent further complications, such as inflammation and infection. However, it is not an easy job to locate the exact location of the foreign body in the soft tissue especially if it is very small in size. We describe an unusual case of an embedded broken endodontic file in the buccal mucosa that may have been lost during previous endodontic procedure which was left incomplete. The location of the foreign body (endodontic file) was accurately identified using routine radiographic procedure (RVG), which was then safely removed by minimal invasive surgical intervention, followed by completion of the endodontic treatment of the involved teeth using MTA for buccal perforation repair.

A fundamental principle in traditional dental practice has been the preservation and rehabilitation of natural teeth. Endodontic treatment procedures have played a key role in this context in the retention and restoration to function of teeth affected by pulp and/or periapical pathosis..The extraction of hopeless teeth is considered as the last resort due to limited restorative options or financial constraints.With the emerging field of implant dentistry gaining fast acceptance, the prevailing opinions on treatment planning for diseased teeth are changing. Many practitioners consider the single-tooth implant as a reasonable alternative to the preservation of the natural dentition. Consequently, today's practitioner is faced with a fundamental dilemma, should a tooth be retained through nonsurgical endodontic treatment or should it be extracted and replaced with an single-tooth implant? This paper Reviews the factors influencing the treatment planning and decision making between both these viable treatment options and identifies key issues that need careful consideration in planning the most appropriate course of care in a given clinical situation.

Anatomic variations may be present in any tooth. Knowing the typical morphology and their variations helps in better prognosis of the treatment performed. The result of successful endodontics revolves around knowledge, respect, and appreciation for root canal anatomy, and careful, thoughtful, meticulously performed cleaning and shaping procedures. Knowledge of pulpal anatomy, it's possible variations is critical for success in endodontic and lack of such knowledge may lead to treatment failure. The most typical anatomy of a mandibular second molar is the presence of two roots and three root canals, but variations in the number of roots as well as canal morphology are not uncommon. This includes single canal, two canals, three and four canals, five canals and C-shaped canal system. Because proper cleaning, shaping, and three dimensional obturation of the entire root canal system is regarded as an important determinant to good prognosis, the variations in root canal system, thus, represents a challenge to its proper diagnosis, debridement and obturation.

Aim: Comparative evaluation of the fracture resistance of endodontically treated maxillary central incisors restored with prefabricated glass fiber posts and experimental dentin posts prepared human root dentin.
Materials & method: Thirty six extracted human Maxillary central incisors were divided in to three groups. In Group-I (Control group) 12 samples, Group-II (Glass fiber posts)12 samples, Group-III (Dentin posts) 12 samples. Twenty four teeth were restored with Glass fiber posts and Solid dentin posts and numbered as Group-II and Group- III respectively while Group-I acted as a control, without any posts only core build up. Teeth were loaded at 130º angle to their long axes after core build up and the failure load were recorded.
Result: Statistical analysis showed that Group III (Dentin posts) (120.9 ± 1.447) and Group II (Glass Fibre posts) (118.6±1.437) the mean failure load value was significantly higher than Group I (Control group) (59.71±2.684). There had no statistically significant difference between group II (Glass fiber posts) and group III (Dentin posts) (Table-1) (Graph-1).
Conclusion: Teeth restored with the dentin posts exhibited marginally better fracture resistance than those restored with glass fiber posts.

Type 2 diabetes mellitus is associated with persistent poor glycemic control which inturn has an impact on the oral cavity, resulting in oral manifestations. The aim of this study is to evaluate the effects of caries risk factors such as bacteriological counts, oral hygiene assessment, and frequency of daily sugar exposure on the caries experience among Type 2 diabetic and non diabetic individuals in Kanpur Population. 100 subjects with dental caries, in the age group 30-70 years, were further divided into Group I (n=50) included Type II diabetes mellitus patients and Group II (n=50) included non-diabetic patients with dental caries. Lactobacillus and Mutans streptococcus colony counts, Silness and Leo indices for plaque score, questionnaire for evaluating oral hygiene practices, a3-day dietary record to evaluate the frequency of daily sugar intake and the prevalence of dental caries was assessed by obtaining the DMFT scores among the subjects of both the groups. Type 2 diabetic patients showed statistically significant increase in the colony counts of Streptococcus mutans (90%) and Lactobacilli, a significantly higher mean plaque indices score and high DMFT score, when compared to non-diabetic patients .Superior oral health habits and higher frequency of sugar intake was observed in subjects of the non-diabetic group when compared to the Type 2 diabetes mellitus patients. In conclusion, our study showed that increase in acidogenic microbes, high plaque scores, less oral hygiene assessment led to high occurrence of caries among Type 2 diabetes mellitus patients when compared to nondiabetic patients.

Aim: To compare the incidence of flare up between single visit and multiple visit endodontic therapy in mandibular molars to find the best possible treatment for the patient in minimal time and cost.
Method: A retrospective study was done in Department of conservative dentistry and endodontics. A total of 300 endodontically treated mandibular molars were selected. They were divided into two groups- Group 1 where single visit endodontic treatment was done and Group 2 where multiple visit endodontic treatment was done using the same techniques. Incidence of flare up was evaluated on the basis of age, gender and preoperative diagnosis between both the groups.
Result: Flare up rate was found to be higher in females and in the age group of 40-60 years. The incidence of flare up was independent of preoperative pulp and periapical status in single visit and multiple visit endodontic therapy.
Conclusion: Single visit endodontic treatment can be safely carried out in all cases of symptomatic, asymptomatic irreversible pulpitis and chronic apical periodontitis if meticulous biomechanical preparation and irrigation is done. Flare up was found to be more in 40 – 60year age group and in females.
Keywords: Flare-up, single visit endodontic treatment, Multiple visit endodontic treatment, irreversible pulpitis, chronic apical periodontitis

Context: Hand washing by a dental health professional before having contact with a patient's oral cavity is considered a fundamental dental clinic infection control measure. Aims: The aim of this study was to evaluate bar soap and liquid soap from dental departments for microbial contamination while it was in use. Settings and Design: This exploratory, cross-sectional study was carried out to identify microorganisms' presence in handwashing with liquid and bar soap at clinical and nonclinical departments in a dental college. Subjects and Methods: In the 2-month study period, all the dental students, dental faculty, and the other auxiliaries present were the participants, and a total of 35 handwashing place samples from 15 different dental departments were collected. The test tube samples of bar soap and liquid soap were all transferred to the microbiology laboratory for microbiological analysis of the samples. Statistical Analysis Used: Data were analyzed using a one-sample paired t-test and independent Student's t-test. Results: Nine different microbial species were identified. In both soaps, the abundance of Staphylococcus aureus was higher as compared to that of other microorganisms. Further, in both soaps, the mean number of microorganisms increased statistically significantly (P < 0.05 or P < 0.01 or P < 0.001) at post-use as compared to at pre-use except Aspergillus niger in liquid soap. However, the post-use mean abundance of microorganisms was found similar (P > 0.05) between the two groups (soaps). Conclusions: The microbial load of the in-use bar soap and liquid soap constituted a mixed flora of Gram-positive bacteria, Gram-negative bacteria, aerobes, anaerobes, and fungi. The results indicate that the bar soap under "in-use" condition harbors more of microorganisms as compared to that of liquid soap, and handwashing with such a soap may lead to the spread of infection.

Aim & Objective: To detect and compare micro leakage of nano composites and zirconia restorations done on extracted teeth using nano composites and zirconium restorative material under confocal microscope. Materials and Methods: 20 caries free maxillary premolars were collected for the study. Class II-box only preparation was done on all extracted teeth out of which 10 teeth were restored using nano composite (ivoclar) and remaining 10 teeth were restored with zirconium ceramic material designed using CAD\CAM. All samples were subjected to thermocycling followed by immersion in Rhodamine-B dye solution for 48 hrs. The samples were sectioned in mesiodistal direction using minitom and dye penetration observed under a confocal laser electron microscope. The results were subjected to statistical analysis. Results: Group II Zirconia ceramic material shows lesser microleakage than group I nano composite. Conclusion: Based on this study it is advisable to use Zirconia ceramic Material for restorative purpose to minimise the micro leakage, further studies with greater sample size is a must to prove its accuracy.

Aim: The aim of this study was to evaluate the precipitate and its thickness formed by interaction between 5.25% sodium hypochlorite and 2% chlorhexidine and its prevention by using 18% etidronic acid and 99% absolute alcohol. Methodology: 30 single rooted human extracted teeth were used. Following cleaning and shaping, all teeth were decoronated and divided into one 3 groups with 10 teeth in each group. All canals of teeth were irrigated with 5.25% sodium hypochlorite and 2% chlorhexidine. As control Group, in group A saline was used as intermediate flush. In experimental groups, group B and group C, 18% etidronic acid and 99% absolute alcohol was used as an intermediate flushes respectively. Statistical Analysis:-one way variance of analysis and Tukey's test was used. Results: Group A and B samples showed significant concentration of precipitate respectively. Group C showed less evidence of precipitate. Conclusion: Within the limitation of this study, it was observed that 99% absolute alcohol had better efficacy in the prevention of orange brown precipitate when compared to 18%etidronic acid.

Preserving the pulp vitality is the main aim of present day dentistry. However due to a myriad of conditions, the use of posts may have to be considered as the last therapeutic option. Generally, endodontically treated teeth have already undergone significant coronal destruction and a pertinent loss of radicular dentine. In such a condition the non metallic posts help to bring the concept of an endoesthetic restorative continuum closer to reality by providing an esthetic post, a composite core and an automixed resin luting cement , thus formulating a monobloc that ensures not only high quality esthetics but is also safe , durable and easy to use for the clinician.
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