Maxillary Permanent Molars Research Articles

Exploring the Association Between Third Molar Agenesis and Carabelli Traits: A Cross-Sectional Study.

Background/Objectives: Dental agenesis is the congenital absence of at least one tooth and has been associated with several other developmental dental conditions, such as morphological dental alterations and Carabelli trait. This study sought to investigate whether third molar agenesis is associated with Carabelli traits in permanent molars. Methods: This was a cross-sectional study that used a convenience sample obtained from the orthodontic records of German patients. Patients with syndromes, oral clefts, congenital alterations including dental agenesis (except agenesis of third molars), and severe cases of bruxism with a loss of tooth tissue were excluded. Teeth with cavitated lesions of dental caries, occlusal wear, restorations, and evident dental deformities were not included in the evaluation. The Carabelli trait was evaluated in the permanent maxillary molars. The Carabelli trait was classified according to its expression for each tooth as either absent, negative, and positive expressions. Third molar agenesis was evaluated only in patients older than 10 years old (based on when initial tooth formation should be visible in the panoramic radiographs). The two-sided Chi-squared test was used to investigate the association between the conditions, using an alpha of 5% (p < 0.05). Results: A total of 155 patients (74 females and 81 males) were investigated; 39 had third molar agenesis and 75 had the Carabelli trait. There was no statistical significance difference between patients with third molar agenesis and those with Carabelli traits in relation to sex (p > 0.05). The Carabelli trait was more common in first molars than in second molars. There was no statistical significant association between third molar agenesis and Carabelli traits (p > 0.05). Conclusions: Third molar agenesis was not associated with the Carabelli trait in the permanent molars in this population.

Incidence and effect of an extra root on the crown morphometry of the maxillary second molars among Malaysian Mongoloids.

This study aimed to investigate whether the presence of two palatal roots on permanent maxillary second molars (MSMs) can affect the crown size and crown's buccolingual and mesiodistal diameters. A retrospective study was conducted using 592 CBCT scans to investigate 1120 MSMs of Mongoloid Malaysians. 3D models were created to assess the four-rooted MSMs and other related teeth carefully. Crown size and crown's buccolingual and mesiodistal diameters were measured for the four-rooted MSM, the adjacent maxillary first molar (MFM), and their antimeres to investigate the effect of the presence of an extra root on the size and morphological features of the crown of these associated teeth. Only six out of the 1120 MSMs displayed four roots (0.53%). The incidence was 0.67% (2/298) for the Malay males and 0.4% (1/247) for the Malay females, with the Malay male having a bilateral occurrence of four-rooted MSM. The incidence was 0.34% (1/294) for the Chinese males, while 0.71% (2/281) was detected in Chinese females. Interestingly, the four-rooted MSMs showed a wider mesiodistal distance than their three-rooted antimeres in three out of four cases. The presence of two palatal roots may also increase the crown's buccolingual diameter. The presence of anatomical variations and the dramatic change in crown measurements can be good indicators of the presence of extra roots, including in some of their related neighbours. This might help dentists to take precautionary measures when performing tooth extractions and endodontic therapy.

The Correlation Between Crown Size and Presence of MB2 in First and Second Permanent Maxillary Molars Using Cone-Beam Computed Tomography

The Correlation Between Crown Size and Presence of MB2 in First and Second Permanent Maxillary Molars Using Cone-Beam Computed Tomography

Microdontia of Bilateral Permanent Maxillary Second Molars: A Rare Case Report

During routine dental examinations, abnormalities of the oral and dental tissue are frequently found, and the prevalence of these anomalies varies across various populations. In cases of microdontia, teeth commonly affected are maxillary lateral incisors, third molars, and supernumerary teeth, respectively. This publication aims to provide the details and facts of a highly uncommon case of microdontia of bilateral permanent maxillary second molars. It is uncommon for many dental abnormalities to develop simultaneously in a nonsyndromic patient.

Root anatomy and canal configuration of human permanent maxillary third molar - systematic review.

Knowledge of the root canals configuration is essential for the success of endodontic treatment. The main aim of the systematic review is to determine the number of roots and the number of root canals in maxillary third molars, in addition, where possible, to determine the Vertucci classification. This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines. The study protocol was registered and approved on the International Prospective Register of Systematic Reviews PROSPERO (Reg. No: CRD42022366444) before the start of the study. Twelve studies were included in the analysis, differing in sample origin and methodology. The combined studies were analyzed based on the number of roots, number of canals, and root canal configurations, and the findings were compared with those of other international studies. Analyzing the available research results regarding the root anatomy and canal configuration of the third maxillary molar, the most commonly maxillary third molars had 3 roots (59.00%). Single-rooted teeth (24.20%) or double-rooted teeth (13.80%) were less common. In addition, it was observed that maxillary third molars typically possessed three root canals (47.28%) and the MB (mesiobuccal), DB (distobuccal), and P (palatal) canals most often showed Vertucci Type I (59.53%, 95.83% and 98.61%, respectively) in three-rooted form. Due to the small number of available studies, it is necessary to conduct further analyses taking into account demographic and ethnic differences that may affect the anatomical and morphological structure of the teeth.

Caffeine induces alveolar bone loss in rats submitted to orthodontic movement via activation of receptor activator of nuclear factor ҡB, receptor activator of nuclear factor ҡB ligand, and osteoprotegerin pathway

Caffeine is a widely consumed substance with several effects on bone metabolism. This study aimed to investigate the effect of caffeine on the bone tissue of rats submitted to orthodontic movement. Twenty-five male Wistar rats underwent orthodontic movement (21 days) of the first permanent maxillary molars on the left side. The experimental group (caffeine; n= 13) and control group (n= 12) received caffeine and water, respectively, by gavage. Microcomputed tomography was performed to analyze orthodontic movement. Histologic analysis of the inflammatory infiltrate and osteoclast count by tartrate-resistant acid phosphatase were conducted. Maxilla tissue was evaluated for receptor activator of nuclear factor ҡB (RANK), RANK ligand (RANKL), and osteoprotegerin by immunohistochemistry. Caffeine exhibited a lower bone volume/tissue volume ratio (78.09% ± 5.83%) than the control (86.84% ± 4.89%; P<0.05). Inflammatory infiltrate was increased in the caffeine group compared with the control group (P<0.05). A higher number of tartrate-resistant acid phosphatase-positive cells was observed in the caffeine (9.67 ± 1.73) than in the control group (2.66 ± 0.76; P<0.01). Immunoexpression of RANK and RANKL in the caffeine group was greater than the control (P<0.05). The use of caffeine thermogenic induces alveolar bone loss in rats submitted to orthodontic movement via activation of RANK, RANKL, and osteoprotegerin signaling pathways.

Frequency of Second Mesiobuccal Canal in Permanent Maxillary Molars: An Observational Study

Background: The success of root canal therapy in endodontics is heavily dependent on identifying a second mesiobuccal canal (MB2) in permanent maxillary molars. A comprehensive understanding of internal anatomy, particularly the recognition of MB2, is crucial for the effective treatment of this commonly encountered tooth. This study aimed to investigate the prevalence and occurrence of the second mesiobuccal canal in permanent maxillary first and second molars. Methods: This cross-sectional study that was conducted at the Department of Conservative Dentistry &amp; Endodontics, Military Dental Centre Dhaka, Bangladesh from January 2018 to December 2018. The analysis involved a total of 200 maxillary first molars and 200 maxillary second molars. In the initial phase for both groups, teeth were examined with the naked eye followed by microscopic assessment. Data analysis was conducted with MS Office tools. Results: In naked eye observation, the frequency of MB2 canals in the first molar teeth was found 64%, and in the second molar teeth it was found 56%. On the other hand, by microscopic assessment, the frequency of MB2 canals in the first molar teeth was found 96%, and in the second molar teeth, it was found 84%. Conclusion: The occurrence of the second mesiobuccal canal (MB2) in permanent maxillary first molars is more common than in the second molars. Microscopic assessment proves to be more effective than naked eye assessment for detecting the presence of MB2 in both maxillary first and second molars. J Bangladesh Coll Phys Surg 2024; 42: 133-138

An In-Vitro Study to Find the of Frequency of MB2 Canal in Permanent Maxillary Molars

Present in-vitro research conducted to find out the frequency of second mesiobuccal canals in permanent maxillary molars. Eighty extracted, intact maxillary permanent molars were selected for the present study. Following that, a slow-speed diamond disc was used to divide the occlusal sections of the crowns at the cement-enamel junction. Using a safe-end diamond bur, overhanging dentin that covered the canal orifices was removed to allow straight line visibility. Under an x8 magnification, the teeth were photographed from their occlusal side. Result showed that the first and second maxillary molars, MB2 canals were found in 70% and 55%, respectively. In conclusion it is crucial during endodontic procedures on maxillary molars to cautiously check pulpal floor to detect any "extra" canals, notably the second mesiobuccal canal, by scraping away the constrictive dentin above the orifices.

FREQUENCY OF SECOND MESIOBUCCAL CANAL IN PERMANENT MAXILLARY SECOND MOLARS AT A TERTIARY CARE CENTRE OF NEPAL

Background: The success of endodontic treatment relies on the precise identification of root canals followed by cleaning, shaping, and obturating the canals. Mesiobuccal root of maxillary second molar teeth present wide variations with regard to the number and type of root canals. The complexity of the root canal varies widely in different ethnic groups. The study aimed to determine the prevalence of second mesiobuccal canal (MB2 canal) in maxillary second molar. Methods: A descriptive cross-sectional study was conducted at Department of Conservative Dentistry and Endodontics, Universal College of Medical Sciences, Bhairahawa. A total of 100 permanent maxillary second molar undergoing endodontic treatments were studied. After access cavity preparation ultrasonic tips and magnification loupes were used to open the subpulpal groove in a direction from first mesiobuccal (MB1) canal towards the palatal canal to locate the second mesiobuccal (MB2) canal. Radiovisiography (RVG) was taken to confirm the presence of MB2 canals. Results: MB2 canals were detected in 52 teeth out of 100 teeth that were studied. It was found that the younger adult (18-35 years) tends to have a higher proportion of MB2 canals (65.6%) as compared to the middle-aged elderly (36-55years) in whom it could be identified only 33.4% of the time. Conclusions: Based on this study, it can be concluded that the prevalence of MB2 canal in mesiobuccal root of the permanent maxillary second molar is high.

Enhanced Recovery of Local Anesthesia in Pediatric Patients: The Impact of Photobiomodulation on Reversing Anesthesia Effects.

BACKGROUND The split-mouth study design is used in oral health research and usually consists of 2 treatments randomly assigned to either the right or left side. This split-mouth study aimed to evaluate the efficacy of photobiomodulation on reversal of local anesthesia in 50 children aged 8-10 years. MATERIAL AND METHODS The study was conducted among 50 children: 27 girls and 23 boys, aged 8-10 years (mean age 9.38±1.15 years), who presented 2 carious maxillary permanent molars. One side was randomly assigned to the laser group (50 teeth), and the contralateral side to the control group (50 teeth). At the end of the treatment, photobiomodulation (PBM) was performed in the area of infiltration at 6 points, with 635 nm (25 children) (250 mW, 500 mW/cm², 15J) and 808 nm (25 children) (200 mW, 400 mW/cm², 12J) (SmartM PRO, Lasotronix, Poland). On the contralateral side, the laser's off-mode applicator was used. Anesthetic effect was evaluated by palpation test (soft tissues) and electrical test (dental pulp). RESULTS After 15 minutes, in the laser group the return to normal sensations in the palpation test showed 88% (808 nm) and 68% (635 nm), and only 20% in the control group (P=0.04123). After 45 minutes, all the participants from the PBM group returned to normal sensations (P=0.21458). Dental pulp's excitability threshold was lower for both wavelengths compared to the control group (P=0.000001). CONCLUSIONS The identification of factors accelerating the recovery time to normal function, such as PBM, can be used as important data to eliminate self-injury secondary to local anesthesia (LA) in children.

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.

Cervical headgear effectiveness in distalizing molars in relation to patient compliance.

The purpose of this study was to measure the effectiveness of the cervical headgear for distalizing first permanent maxillary molars in relation to hours of use. This was a one-centre, prospective, clinical study conducted at the Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece. Participants (N = 26; 17 females, 9 males) were patients with no history of orthodontic treatment, no syndromes or clefts, and Angle's Class II malocclusion, where the treatment plan included a cervical headgear. They were instructed to wear the appliance for at least 12 h per day. A TheraMon® microsensor was embedded in the headgear's strap to objectively measure wear-time. To measure tooth movement, pre- and post-treatment digital models were superimposed, using the palate as a reference area; translation and rotation were measured along three axes. Superimposition and movement measurements were made with the Viewbox 4 software. Average treatment time and headgear wear were 130 days and 55 days, respectively, i.e. 10.1 h/day. During this period, distal movement averaged 1.75 mm with high variability (min 0.2 mm, max 4.5 mm). Distal tipping and rotation had an average of approximately 5 °C. Cumulative headgear wear was significantly correlated with distal movement (r2 = 0.32, P < .002), distal tipping (r2 = 0.27, P < .01), and distal rotation around the long axis of the tooth (r2 = 0.20, P < .05). Compliance is critical for having a successful clinical outcome. Distalization of the molar with a cervical headgear is correlated with the cumulative hours of appliance use, with hours per day being a weaker predictor.

Prevalence Of Second Mesiobuccal Canal In Maxillary Second Molars On The Basis Of Clinical And Radiographic Parameters.

The objective of this study was to determine the prevalence of the second mesiobuccal canal in permanent maxillary second molar in patients presenting to Peshawar Dental College and Hospital. One hundred and twenty patients advised for root canal treatment in the maxillary second molars participated in the study. Two detection procedures, clinical and radio graphical examination were used. Two pre-operative radiographs with different angulations and one post-operative radiograph were taken to examine roots and root canals. Access cavities were prepared and the second mesiobuccal canal was explored using magnifying dental loupes (3.5 x), endodontic explorer (DG16) and size 10 K-file. Descriptive statistics were recorded as percentages, frequencies and mean. The chi-square test was used for gender, age-wise comparison and right and left side of the maxillary jaw. One hundred and twenty patients were recruited in the study. There were 65 (54.2%) males and 55 (45.8%) females. The second mesiobuccal canal was more common in males compared to females (p-value=0.434). The second mesiobuccal canal was most commonly found in 3rd decade with mean age, of 40.5±12.31, (p-value =0.51). The frequencies and percentages of the second mesiobuccal canal in maxillary second molars on the right and left side of the jaw were 70 (58.3%) and 50 (41.7%) respectively (p-value =0.310). The second mesiobuccal canal was found in less than half of the second molars. The most successful method of detection in this study was both clinical and radiographic.

Investigating the impact of diameters and thread designs on the Biomechanics of short implants placed in D4 bone: a 3D finite element analysis

BackgroundDental implants emerge as a dependable and efficacious alternative for patients experiencing partial or complete tooth loss. The stability of these implants is influenced by surface topography and macro-level design. In cases where the height of the maxillary posterior region is diminished, employing short implants can prove advantageous. With the aim of examining the distribution of von Mises stress, strain, and micromovement in D4 bone quality surrounding platform-switched short implants, measuring 6 mm in length and featuring diameters ranging from 4 to 6 mm, as well as different thread designs, an in-depth finite element analysis was conducted under immediate loading conditions. MethodologyA 3D finite element model was constructed to simulate maxillary molar crowns, incorporating an implant with a length of 6 mm and varying diameters and thread designs. The diameters utilized were 4/3.6 mm, 5/4 mm, and 6/4.8 mm, while the thread designs included buttress, square, and triangle patterns. Each model underwent analysis with a 100 N force applied in two directions: vertical and oblique, relative to the long axis of the implant. Stress, strain, and micromovement in the peri-implant region were recorded, employing the Ansys Workbench R v.18.1 software for modelling and analysis.ResultsWhen comparing all three diameters, the wide diameter (6 mm threads) exhibited the lowest values of peri-implant von Mises stresses (3.3 MPa and 35.1 MPa), strains (194 Ɛ and 484 Ɛ), and micromovements (0.7 μm and 1.3 Ɛ) subjected to axial and non-axial loading of a 100 N force. Notably, square microthreads yielded the most favorable stress parameters among the different thread shapes, manifesting the minimum values of stress, strains, and micromovements in their vicinity.ConclusionFor the treatment of atrophic ridges or in scenarios necessitating extensive surgical preparation of the implant site, a combination of short implants, wide diameters, and platform switching can be employed. In situations with reduced bone height and the requirement for an implant-supported prosthesis to replace a missing permanent maxillary molar, the utilization of wide-diameter platform-switched short implants measuring 6 mm in length, featuring a square thread design, should be taken into consideration.

Three-Dimensional Assessment and Comparison of the Maxillary Tuberosity Between Skeletal and Dental Class I and Class II Adults in Maxillary Third Molar Agenesis Using Cone Beam Computed Tomography: A Descriptive Cross-Sectional Human Study.

The objective of this study was to assess and compare the dimensions (width (W), height (H), and length (L)) of the tuberosity distal to maxillary permanent second molar in individuals with skeletal and dental Class I and Class II malocclusions who had maxillary third molar agenesis. Cone beam computed tomography (CBCT) was used to measure the left (L) and right (R) anatomical tuberosity dimensions in three dimensions using the WillMaster software (HDX WILL Corporation, Korea). The measurements were compared between Class I (n = 35)and Class II (n = 35) normo-hypodivergent adult subjects. The dimensions were measured at regular 2 mm intervals from the cementoenamel junction (CEJ) and distovestibular root of the maxillary second molar in terms of the width (e.g., W1, W2, and W3), height (e.g., H1, H2, and H3), length (e.g., L1, L2, and L3) to the posterior limit of the tuberosity. Statistical analysis included descriptive statistics, Mann-Whitney U tests, and intraclass correlation coefficient tests. The width of the tuberosity at LW0, LW1, and LW2 was significantly higher in Class I compared to that in Class II. The right tuberosity in Class II showed significantly higher values in height at all reference points. The right tuberosity at RL0and RL1 exhibited significantly higher values in the length of the Class II group compared to the Class I group. The dimensions of the maxillary tuberosity (width, height, and length) varied between the Class I and Class II groups. Wider maxillary tuberosities were observed in the Class I group, while the Class II group had greater height and length dimensions of the tuberosity.

Crown root ratio and angulation of various permanent teeth in patients with and without cleft lip/palate

ABSTRACT Aims and Objectives: The purpose of this study was to analyze parameters of tooth in subjects with nonsyndromic cleft lip and palate (CLCP) and to compare the findings with the control groups. Teeth in the cleft-affected and nonaffected side in the same unilateral cleft lip and palate (ULCP) patient were also compared. Materials and Methods: The study included 200 subjects in the age group of 12–37 years who were divided into two groups: nonsyndromic CLCP and control group. The control group was further subdivided into skeletal Class I, II, and III subgroups based on ANB, AO-BO, and overjet, respectively. Crown height, root length, total tooth length, crown root ratio (C/R ratio), and tooth angulations of maxillary permanent central incisors, canines, 1st premolars, and 1st molar were measured on orthopantomograms using both ITK SNAP software and manual tracing. Results: Crown heights significantly increased while root lengths significantly decreased in the CLCP patients when compared to control groups. Total tooth lengths of central incisor, canine, and 1st premolar in CLCP patients were found to be decreased significantly. C/R ratios of all the teeth of nonsyndromic CLCP group irrespective of the cleft affected or nonaffected side was found to be increased as compared to the control groups. There was a significant difference seen in crown height, root length and mesiodistal tooth angulations in the cleft affected side when compared to the non affected side in a UCLCP patient’s dentition. However the total tooth length and the C/R ratio were not affected. Conclusion: Common findings of CLCP are aberrant teeth development, altered tooth morphology, and malformed teeth. The severity of cleft has an impact on the tooth development and morphology as it was observed that delayed root development and short roots, decreased total tooth length, increased C/R ratio and variations in teeth angulations in CLCP patients were affected by the presence and severity of cleft.

Premolarization of the Permanent Maxillary Second Molars- Report of A Rare Case

Premolarization of the Permanent Maxillary Second Molars- Report of A Rare Case

Variations in Crown Size and Root Canal Configuration in a Sample of Human Permanent Maxillary and Mandibular Molars in Egyptian Population

Variations in Crown Size and Root Canal Configuration in a Sample of Human Permanent Maxillary and Mandibular Molars in Egyptian Population

Single visit apexification of a permanent maxillary molar using bio dentine: A case report

Single visit apexification of a permanent maxillary molar using bio dentine: A case report

THE USE OF CONE BEAM COMPUTED TOMOGRAPHY TO EVALUATE OF RESULTS OF THE RAPID EXPANSION OF THE HARD PALATE WITH DENTAL ANOMALIES

The crowding of the permanent incisors with accompanying rotations or anterior cross bite is commonly seen during eruption of the permanent lateral incisors. When crowding is limited to a few millimeters, sufficient space may allow normal growth, but when the upper jaw is narrow and crowding exceeds this amount, rapid expansion of the hard palate may be an effective method. The purpose of this study was to study the method of cone beam computed tomography to evaluate the results of rapid palatal expansion in the narrowing of the upper dentition and the lack of space for incisors and the reaction of intact permanent molars, when fixing the apparatus on primary second molars in the absence of posterior cross bite. The study involved 20 children (age 7-10 years) who were treated with the Haas apparatus. The Haas apparatus was fixed on the upper second primary molars and on the primary canines. Cone beam computed tomography was performed before and after palatal suture rupture. A decrease in incisor crowding was found in all patients. The width between the permanent molars in the diameter has increased significantly, the distance between the tops of the roots of the upper permanent molars has increased more than between the crowns of the teeth. Application of the method shows the possibility of expanding the sky in the transverse direction. The use of a Haas apparatus attached to primary teeth in early mixed dentition in the absence of posterior cross bite is effective and provides a pronounced planned transverse growth of the jaw and can be indicated to expand the anterior part of the upper jaw to eliminate crowding of the upper incisors. With rapid expansion, there are favorable spontaneous changes in the palatal vertical position of the maxillary permanent molars in the opposite direction of expansion and there is the potential to mimic the expected natural transverse growth. Fixation of the apparatus used for this procedure on the primary molars and keeping the permanent molars unused means the prevention of periodontal damage, loss of attachment, demineralization and external resorption of the roots of permanent molars.