Mandibular 2nd Premolars Research Articles

Evaluation of root and canal morphology of mandibular premolar amongst Saudi subpopulation using the new system of classification: a CBCT study

BackgroundThe clinician should have complete knowledge of the normal anatomy of the root as well as complexities in the root canal configuration for a better outcome, as missed or improper handling of the canal system can lead to the failure of an entire endodontic procedure. The present study aims to assess the morphology of roots and canals in permanent mandibular premolars in the Saudi subpopulation with a new classification system.MethodsThe present study includes 1230 mandibular premolars (645 first premolars and 585-second premolars) from 500 CBCT images of the patients, including retrospective data. iCAT scanner system (Imaging Sciences International, Hatfield, PA, USA) was used to obtain the images; scanning of 8 × 8 cm images was performed at 120 KVp and 5–7 mA with a voxel size of 0.2 mm. The new method of classification presented by Ahmed et al. 2017 was used to record and classify the root canal morphology, followed by recording the differences regarding the age and gender of the patients. Comparison of canal morphology in lower permanent premolars and its association with gender and age of the patients was done by Chi-square test/ Fisher exact test; the significance level was set at 5% (p ≤ 0.05).ResultsThe left mandibular 1st and 2nd premolars with one root were 47.31%, with two roots were 2.19%. However, three roots (0.24%) and C-shaped canals (0.24%) were reported only in the left mandibular 2nd premolar. The right mandibular 1st and 2nd premolars with one root were 47.56%, with two roots were 2.03%. The overall percentage of the number of roots and canals in the first and second premolars 1 PM 1 (88.38%), 2 PM 1 B 1 L 1 (3.5%), 2 PM B 1 L 1 (0.65%), 1 PM 1–2−1 (3.08%), 1 PM 1–2 (3.17%), 1 PM 1–2−1–2 (0.24%), 3 PMMB 1 DB 1 L1 (0.48%). However, the C-shaped canals (0.40%) were reported in right and left mandibular second premolars. No statistically significant difference was reported between mandibular premolars and gender. A statistically significant difference was reported between mandibular premolars and the age of the study subjects.ConclusionType I (1 TN 1) was the major root canal configuration in permanent mandibular premolars, which was higher among males. The CBCT imaging provides thorough details about the root canal morphology of lower premolars. These findings could support diagnosis, decision-making, and root canal treatment, for dental professionals.

Roots and Root Canals Characterization of Permanent Mandibular Premolars Analyzed Using the Cone Beam and Micro Computed Tomography—A Systematic Review and Metanalysis

This current paper aims to review the literature on the root canal configuration (RCC) and root structure of permanent mandibular premolars. To find the published scientific literature on the RCC of mandibular premolars up to July 2022, a systematic search of four electronic databases was performed. The studies were selected, rendering to a predetermined point of reference: "mandibular 2nd premolar", "root and canal system", "morphology of root and canal", "root and canal configuration", and "morphology", along with "anatomy" and "mandibular premolars". Cross-referencing along with screening through the bibliographies of the chosen articles resulted in the identification of further studies. In the current study, we examined 30 different articles, and we chose them based on the quality of research investigations. From 3471 retrieved studies, a total of 15981 mandibular 2nd premolars were observed in 30 studies. The mean JBI score for studies assessing the structure of the root, as well as the root canal of the mandibular 2nd premolar, was 7.78 ± 0.81. We have found a pooled prevalence of 91.82% for Vertucci class I root canal morphology and 78.63% pooled prevalence of single-rooted mandibular second premolar. A total of 8677 mandibular 1st premolars were observed in 22 studies. The mean JBI score for studies assessing the structure and anatomy of the root, as well as root canal of mandibular 1st premolar, was 7. 95 ± 0.85. We have found a pooled prevalence of 74.34% for Vertucci class I root canal morphology and 85.20% pooled prevalence of single-rooted mandibular 1st premolar. Mandibular first and second premolars were mostly single-rooted teeth (89.5-100%). The most frequently seen RCC is a 1-1-2-/2 (type V-Vertucci's), followed by 1-1-2-/1 (type IV- Vertucci's; type III-Weine's), and finally RCC 2-2-2-1 (type IV-Vertucci's; type III-Weine's). Presently, the imaging of CBCT is the most used research approach for studying Mn2Ps' structural characteristics.

MANDIBULAR 2ND PREMOLAR WITH TWO ROOTS AND THREE CANALS: A CASE REPORT

Mandibular premolars have earned the reputation for having an aberrant anatomy. Literature is replete with reports of extra canals in mandibular second premolars, but reports about the incidence of extra roots in these teeth are quite rare. Before initiating any endodontic therapy, probability of extra canals should be considered. The Incidence of three canals in mandibular second premolar has been reported to be 0.46-0.5%. The present report describes nonsurgical endodontic treatment of mandibular second premolars with three canals. This case report explains non-surgical endodontic treatment of a mandibular second premolar with two separate roots and two separate buccal, and lingual canal orices and three canals namely Mesio-buccal, Disto-buccal and Lingual. Close attention to anatomic variations, thorough advance radiographic method like CBCT, thorough evaluation of the pulp chamber oor, and use of magnifying and optical devices have been recommended for the success of endodontic treatment of mandibular second premolars with complicated root canal system anatomy.

Age estimation by applying cameriere method for lower 2nd premolars using orthopantomograph

Introduction: The aim of this study was to determine age by Cameriere method using mandibular 2nd premolar by Panoramic Radiographs. Materials and Methods: A total of 225 panoramic radiographs of Kashmiri subjects (108 males and 117 females), aged between 15 and 70 years were analyzed. According to Cameriere et al. measurements of the pulp and tooth areas were done. The morphological variables i.e, pulp tooth ratio, age and the subject’s gender were entered in a Microsoft Excel spreadsheet for use as predictive variables for age estimation. Chronological age of an individual was calculated by subtracting the birth date from the date on which the radiographs were exposed for that particular individual. Results: It was found that the 2nd premolar was the closely correlated with age(r=-0.951) and SEE 3.32 years. Conclusion: As the development of teeth varies among populations and is genetically determined, it becomes imperative to derive population specific data bases. From the results of this study, it may be concluded that the use of Cameriere’s age-related variables in lower premolars and canine and the application of the new regression formulae on data obtained from orthopantomograph lead to accurate age estimates, if at least the selection criteria are respected and good quality orthopantomograph with clear radiological images are used.

Case report of retained deciduous 2nd molars in an adult patient having congenitally missing mandibular 2nd premolars

Hypodontia is sometimes observed in adult patients and is frequently associated with missing 3rd molars. However, it can also involve other teeth such as canines, lateral incisors and premolars. In this case report, we describe a case of an adult patient having bilaterally missing mandibular second premolars and instead, presence of retained deciduous 2nd molars. Also, a possible insight into the etiology of retained deciduous teeth is discussed.

Influence of Propolis, Ozone and Photodynamic therapy in root canal disinfection on resin bond strength to radicular dentin.

The aim of the present study was to assess post space disinfection using different irrigants and their effect on radicular dentin bond to SERC. Forty single rooted mandibular 2nd premolars were collected and disinfected. All samples were decoronated maintaining root length of 12 mm and embedded vertically in acrylic resin. Shaping of the canal was performed using reciprocating system. Canals were dried using paper points and obturated with gutta percha via lateral condensation. Peso-reamers were used to create post space up to 10 mm. The post space was irrigated with 1% NaOCl before being randomly allocated into four groups (n = 10) according to different methods of canal disinfection. Samples in group 1 were subjected to photoactivated disinfection (PAD), group 2 irrigated with ethanol based propolis group 3 disinfected using ozone and group 4 irrigated with 2.25 % NaOCl with 17 % EDTA and ECL. GFP was fitted using SERC. Each sample was cut into 1 mm from coronal, middle and apical and subjected to pushout bond strength (PBS) via universal testing machine. Fracture analysis were confirmed by stereomicroscope at 40x magnification. For comparison of means, Analysis of variance (ANOVA) and Tukey multiple comparison test was used maintaining the level of significance at p < 0.05. The highest PBS at all three levels were found in group 4, canal disinfected with 2.5 % NaOCl with 17 % EDTA and ECYL. Whereas, the lowest PBS was observed in group 1. Inter group comparison, prosthetic space disinfected with propolis extract showed no significant difference to group 4 canal disinfected with 2.5 % NaOCl with 17 % EDTA and ECYL at all three levels (p > 0.05). Intra group comparison in all experimental groups showed no significant difference was noted in coronal and middle thirds of group 1, group 2 and group 3 respectively (p > 0.05). 2.5 % NaOCl with EDTA and ECL treatment (group 4) remains the gold standard when used as a final canal irrigant. Propolis can be used as potential irrigant for canal disinfectant provided if the composition becomes standardized.

AN IN-VITRO ASSESSMENT OF ANTIOXIDANTS TREATMENT AFTER NON VITAL BLEACHING ON MARGINAL ADAPTATION OF COMPOSITE RESTORATION

Aim: This study impel with aim of evaluation and comparison of marginal adaptation of composite restoration in teeth bleached intracoronally after using different neutralizing antioxidants in in vitro environment. Materials and Methods: This study included 40 intact, non carious human mandibular 2nd premolars having comparable sizes. Endodontic treatment was carried out for all the teeth and were distributed in 4 groups randomly with each group containing 10 samples (n=10). Group A was negative control group, Group B positive control, Group C & D antioxidants group. Except samples of Group A all other samples were subjected to 35% hydrogen peroxide to attain intracoranal bleaching process. In Group B after bleaching teeth were restored immediately with composite, In Group C & D before completing the restoration samples were treated using 10% concentration of Sodium Ascorbate, and 10% sodium thiosulphate antioxidant respectively. All test samples were subjected to thermal cycling procedure and were immersed into 2% methylene blue for 24 hours followed by longitudinal sectioningwith a diamond disk. Micro leakage test under stereomicroscope with a 0 – 4 scoring criteria was utilized for evaluation. Statistical analysis was done using ANOVA test. Result: significantly higher micro leakage (p=0.0012) was appreciated in Group II. Statistically insignificant difference between Group I, III and III and group III and IV together was appreciated. Conclusion:The compromised sealing ability of resin composite can be regained with use of antioxidants to tooth bleached intracoronally.

Prevalence of Dental Anomalies in a Sample of Orthodontic Patients in Erbil City

Objective: Dental anomalies are abnormal morphological development of dentition during various periods of tooth development and have an important role in the development of various kinds of malocclusions. If dental anomalies not diagnosed, they can make dental and orthodontic treatment more difficult. So, orthodontists and the general dental practitioner must investigate patients carefully. The objective of the current study was to determine the prevalence and distribution of dental anomalies in a sample of orthodontic patients in Erbil city using orthopantomogram.` &#x0D; Methods: Four hundred fifty-eight orthopantomograms of orthodontic patients with age of 16-40 years evaluated to determine the prevalence and distribution of the hypodontia, impaction, microdontia, and supernumerary tooth.&#x0D; Results: 15.06% orthodontic patients: 21 males and 48 females had at least one dental anomaly. Impaction and hypodontia were the most common dental anomalies with no significant difference between genders. Maxillary canines were more commonly impacted tooth, whereas maxillary lateral incisors were the most common tooth agenesis among genders.&#x0D; Conclusions: Impaction was the most prevalent dental anomaly, and maxillary canines were the most involved teeth and are in agreement with many studies among various populations. The most frequently missing teeth were the maxillary lateral incisors. However, mandibular 2nd premolar was the most common hypodontia in some studies.

Bone Density Level Difference between Maxillary and Mandibular 2nd Premolar and 1st Molar in Iraqi Adults with Class I Occlusion

Background: Development of techniques that could adequately provide anchorage in moving individual tooth or groups of teeth in desired direction is one of the major concerns of orthodontic. Mini-implants provide reliable stable anchorage. The aim of this study was to compare of the bone density between two points within alveolar bone to decide which one was more reliable for insertion of mini-implant. Materials and method: Computed tomographic images were obtained for 70 patients (24 males and 46 females) with an age range 18- 30 years. Bone density of buccal cortical and cancellous bones was measured between 2nd premolar and 1st molar at two preselected level (points 3 and 6 mm) from the alveolar crest in both maxilla and mandible. Results: According to independent t-test, the bone density at point 6 mm was higher than that at point 3 mm with a statistically significant difference between them in both maxilla and mandible except in maxillary cancellous bone which shows a non-significant difference. Conclusions: It was concluded that the alveolar bone density increased from the alveolar bone crest toward the basal bone. Point 6 mm is more recommended in the upper jaw, while in the lower jaw, point 3 mm is more recommended.

Transplantation of embryonic stem cells improves the regeneration of periodontal furcation defects in a porcine model

Stem cell-based therapy promises to regenerate lost tissue. Embryonic stem (ES) cells are pluripotent and may provide a virtually unlimited source for transplantation. We investigated whether ES cell transplantation improved the regeneration of furcation defects in a porcine model. Experimental periodontitis was induced in the buccal furcations of the bilateral mandibular 2nd premolars of six minipigs. After 4weeks, the lesions were surgically debrided and implanted with collagen matrix alone (control site) or collagen matrix overlaid with porcine ES cells expressing green fluorescent protein (pES/GFP(+) ) (test site). After 3months of healing, the clinical parameters were measured again. The treated teeth with adjacent tissue, and part of the major organs, were processed for GFP immunohistochemistry. We found no obvious teratoma or rejection. The test group had significantly better clinical parameters. Immunohistochemistry (IHC) showed that transplanted pES/GFP(+) cells had differentiated to new periodontal ligament and cementum in the test sites. Surprisingly, GFP(+) cells were also detectable in the repaired control cementum and remote organs. We conclude that using ES cells to improve the regeneration of periodontal furcation defects is feasible. More studies are required to assess this potential treatment's efficacy and safety.

Delayed dental maturity in dentitions with agenesis of mandibular second premolars

To evaluate dental maturity in the mandibular canine/premolar and molar innervation fields in children with agenesis of the 2nd mandibular premolar and to associate these findings with normal control material. Department of Orthodontics, Institute of Odontology, University of Copenhagen. Eighty-three panoramic radiographs (27 girls and 31 boys with agenesis of one mandibular 2nd premolar and 17 girls and eight boys with agenesis of both mandibular 2nd premolars) represented all mandibular second premolar agenesis cases from a material of 2847 radiographs. On each radiograph, dental maturity of all available mandibular premolars, canines and 2nd molars was evaluated and categorized in maturity stages according to Haavikko whose material served as control material. Descriptive statistics given by sample mean, standard deviation and range for each tooth stratified by gender and agenesis. Ninety-five percentage confidence limits and T-statistics were used. p-values <5% were considered significant. In unilateral agenesis, the canines are specifically delayed in both girls and boys, with a larger delay in girls (p=0.009). The second molar is not delayed in boys (p=0.98) but is in girls (p=0.04). The differences in delay for the canine compared to the second molar are significant for both girls and boys. The results show a considerable delay in tooth maturation within the canine/premolar innervation field predominantly in girls. The 2nd molar is delayed in girls but not in boys.

Mandibular Premolar Impaction

Literature specific to impacted premolars is not extensive despite the fact that mandibular 2nd premolars alone account for 2.4&#37; of dental impactions. The purpose of this paper is to describe the radical approach (extraction) of a transversally impacted 2nd premolar in the mandible through a lingual approach due to its peculiar position presuming it will contribute toward the literature regarding impacted mandible premolars.

Endodontic treatment of mandibular second premolar with three root canals using dental operating microscope

Mandibular premolars are one of the most difficult teeth to treat endodontically because of the variations in root canal anatomy(1). There are only a few endodontic publication citing an incidence of mandibular 2nd premolar with 3 root canals. Thorough knowledge of the basic root canal morphology as well as the possible anatomic variations is important for the successful treatment of such cases. This article describes the successful endodontic treatment of mandibular 2nd premolar with 3 root canals treated with the help of operating microscope in a patient with more than two canals also in the contralateral side second premolar. The success of endodontic treatment depends upon thorough debridement and complete obturation of the entire root canal system. For this the knowledge of roots and root canal morphology as well as the possible anatomic variations becomes very important (2,3). The canal morphology of mandibular 2nd premolar can be very complex and variable. Different studies have looked at the root canal morphology of mandibular premolars over years and reported a fairly high percentage of these teeth to have more than one canal.(4-6) Zillich and Dowson (7) have reported that an incidence of 0.4% of mandibular second premolars with three canals. Vertucci(8) does not report any case of mandibular second premolar with three or more canals at the apex. The incidence of three roots is extremely rare (0.1%). Such anatomic variations are quite possible and shouldn’t be thought of as exceptional. Dental operating microscope, with its magnification and illumination helps in the easy detection of hidden canals and allows a more detailed vision of the internal root canal system. With the use of microscope the success rate has definitely increased in the recent past. This article describes the successful endodontic treatment of mandibular 2nd premolar with three root canals with the help of dental operating microscope.

Hypodontia of permanent teeth in a Kenyan population.

To assess the occurrence of hypodontia (except 3rd molars) in a population of orthodontic patients. A retrospective case study. Private orthodontic practice in Nairobi Six hundred and fifteen orthodontic patients aged eight to fifteen years. Hypodontia occurred in 39 children (6.3%). The missing teeth were observed in 24 males (7.2%) and 15 females (5.3%). Of the children with hypodontia, about 80% lacked one or two teeth, 54% had hypodontia involving anterior teeth, 18% lacked single posterior teeth and 8% had two or more teeth missing in the same quadrant. The highest recorded number of missing teeth in any one individual was seven. The most frequently missing teeth were mandibular 2nd premolars (30%), maxillary 2nd premolars (24%) and maxillary lateral incisors (22%) in that order. Our data for hypodontia were within the wide range reported in the literature. The finding of patients with hypodontia involving the anterior teeth and others missing more than two teeth in the same quadrant was an indication of a great need for orthodontic treatment. The present findings reiterate the neeed for a thorough radiographic evaluation of patients prior to removal of permanent teeth for orthodontic reasons.

Brother and sister with Supernumerary tooth Impaction Beneath the Mandibular 2nd Premolar

Brother and sister with Supernumerary tooth Impaction Beneath the Mandibular 2nd Premolar