Mesial Migration Effect on Root Morphology of Mandibular Third Molars

Abstract Objective: To test the hypothesis that there is a relationship between forward mandibular third molar migration and root curvature of the mandibular third molars. Materials and Methods: The study is comprised of 64 patients who had a history of unilateral mandibular first molar extraction before 16 years of age with no other missing teeth or prosthetic restorations in the mandible. The extraction space was fully or partly closed. The mean remaining space was 1.1 ± 0.41 mm. The root angles for the mesial and distal roots of the mandibular third molars were measured on the panoramic radiographs by calculating the differences between the angle formed by the long axis drawn perpendicular to the occlusal plane of the crown of mandibular third molar and the central line of the lower one ninth of the root through the root apex. The differences between the extracted and nonextracted sides for mesial and distal roots were analyzed using a paired sample t-test. Results: Both mesial and distal roots were approximately 8° more vertical on the extraction sides than on the nonextraction sides. The differences were statistically significant. Conclusion: Mesial tooth migration of mandibular third molars reduces the amount of root curvature developing on this tooth.

Download Full-text

The Frequency of Mandibular Third Molar Impaction in Different Types of Vertical Skeletal Faces

Journal of The Pakistan Dental Association ◽

10.25301/jpda.302.118 ◽

2021 ◽

Vol 30 (02) ◽

pp. 118-123

Author(s):

Sana Viqar ◽

◽

Sadia Rizwan ◽

Syed Shah Faisal ◽

Syed Sheeraz Hussain

Keyword(s):

Third Molar ◽

Third Molars ◽

Skeletal Malocclusion ◽

Mandibular Third Molar ◽

Lateral Cephalograms ◽

Significant Difference ◽

Pre Treatment ◽

Mandibular Third Molars ◽

Facial Types ◽

Third Molar Eruption

OBJECTIVE: To determine the frequency of mandibular third molar impaction in different vertical skeletal facial types. METHODOLOGY: Data was collected using pre-treatment records including orthodontic files, pre-treatment lateral cephalograms and OPGs of 90 orthodontic patients. Patients from both genders were included. The age group of selected patients was 18-30 years. Vertical skeletal malocclusion was measured using facial angle and mandibular plane angle on cephalogram to group the subjects into Mesiofacial, Brachyfacial and Dolichofacial patients. Third molar eruption status was assessed using OPG. RESULTS: Results showed that erupted third molars were mostly found in brachyfacial patients. Among 32 erupted mandibular third molars, 16 belong to brachyfacial, 11 belonged to mesiofacial and 5 belonged to dolichofacial group. Complete impaction of mandibular third molar was most common among dolichofacial patients. Among 29 completely impacted mandibular third molars, 14 belong to dolichofacial, 9 belonged to mesiofacial and 6 belonged to brachyfacial group. No significant difference was found for partially impacted third molars among the three groups of facial types. There was higher prevalence of mandibular third molar impaction in females as compared to males. CONCLUSION: Frequency of third molar impaction was found to be highest in dolichofacial patients and lowest in brachyfacial patients due to forward direction of mandibular growth contributing to greater resorption of the anterior border of ramus and the additional space required for third molar eruption.

Download Full-text

Calcifying cystic odontogenic tumor in radiologically normal dental follicular space of mandibular third molars: report of two cases

Clinics and Practice ◽

10.4081/cp.2017.933 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 3

Author(s):

Gargi S. Sarode ◽

Sachin C. Sarode ◽

Ghevaram Prajapati ◽

Mahesh Maralingannavar ◽

Shankargouda Patil

Keyword(s):

Cell Transformation ◽

Histopathological Examination ◽

Third Molar ◽

Odontogenic Tumor ◽

Third Molars ◽

Radiographic Evidence ◽

Odontogenic Epithelium ◽

Mandibular Third Molar ◽

One Year ◽

Mandibular Third Molars

Two cases of calcifying cystic odontogenic tumor (CCOT) of the dental follicle in an impacted third molar without clinical and radiological evidence are reported during routine histopathological examination. In both the cases left mandibular third molar was mesioangularly impacted with pericoronal radiolucency of less than 2.5 mm, which was not indicative of any pathology. As a routine protocol (which is not practiced widely) of our institution, dental follicles associated with extracted molars were sent for histopathological examination. Histopathological features were consistent with CCOT with pathognomonic ghost cell transformation of odontogenic epithelium. The patients were followed for one year with no recurrence. This paper emphasizes the importance of routine histopathological examination of dental follicles associated with asymptomatic impacted teeth without any clinical or radiographic evidence of follicular lesion.

Download Full-text

Is prophylactic extraction of mandibular third molar indicated? A retrospective study.

10.21203/rs.3.rs-32327/v1 ◽

2020 ◽

Author(s):

Zhouxi Ye ◽

Wenhao Qian ◽

Yubo Wu ◽

Bing Sun ◽

Zhiyao Li ◽

...

Keyword(s):

Soft Tissue ◽

Older Patients ◽

Third Molar ◽

P Value ◽

Third Molars ◽

Impacted Teeth ◽

Second Molar ◽

Mandibular Third Molar ◽

Mandibular Second Molar ◽

Mandibular Third Molars

Abstract Background To evaluate the associations of impaction patterns of mandibular third molars (M3Ms) with pathologies caused by them. Methods In this study, 262 patients with 432 impacted M3Ms were included. The pathologies include pericoronitis, mandibular second molar (M2M) caries, and M2M distal periodontal pathology. The impaction patterns of M3Ms and the pathologies were examined, and the M2Ms outcomes after the surgeries were evaluated. χ2 test was used to analyze the data and a P value of <0.05 was considered statistically significant. Results Pericoronitis was the major symptom in all patients, whereas the propensities of M2M distal caries and periodontal pathologies increased in older patients. Soft tissue impacted and vertically angulated teeth were more associated with the pericoronitis (p <0.05); Mesio-angular impacted teeth in less deep positions had greater risks of M2Ms distal caries (p <0.05); Mesio-angular and horizontal impacted teeth in relative deep positions were more likely to cause M2Ms distal periodontal pathologies (p <0.05). Conclusions Extractions of soft tissue impacted teeth in vertical angulations should be considered. While removals of mesially and horizontally angulated or bony impacted teeth could be delayed.

Download Full-text

Presence and Maturation Dynamics of Mandibular Third Molars and Their Influence on Late Mandibular Incisor Crowding: Longitudinal Study

10.21203/rs.3.rs-538924/v1 ◽

2021 ◽

Author(s):

Martina Žigante ◽

Andrej Pavlic ◽

Luka Morelato ◽

Vaska Vandevska-Radunovic ◽

Stjepan Spalj

Keyword(s):

Third Molar ◽

Third Molars ◽

Mandibular Incisor ◽

Dental Maturation ◽

The Third ◽

Irregularity Index ◽

Mandibular Third Molar ◽

Mandibular Third Molars ◽

Dental Plaster ◽

The Relationship

Abstract OBJECTIVE: To investigate the relationship between the presence and dynamics of mandibular third molar development and the occurrence and amount of late mandibular incisor crowding. MATERIALS AND METHODS: Dental plaster casts and panoramic radiographs of 72 orthodontically untreated subjects from the Nittedal growth study, Norway were analysed. The subjects were recalled for check-up at 12, 15, 18 and 21 years of age. Mandibular incisor crowding was assessed using the Little’s irregularity index and dental maturation of the third molars by the Cameriere’s index.RESULTS: The majority of the subjects (64%) had ≥1mm increase in irregularity; 22% experienced increase of 0.1-0.9mm and 14% had unchanged or decreased irregularity. Incisor irregularity increased with age, regardless of absence or presence of third molars. The amount of change in incisor irregularity from 12 to 21 years did not differ significantly between subjects with hypodontia of third molars, extraction and those with third molars present. No differences were observed between erupted, unerupted or impacted third molars. No correlation was found between the amount of change in irregularity and maturation of the third molars.CONCLUSIONS: Occurrence and amount of mandibular late incisor crowding is not significantly influenced by presence or development dynamics of mandibular third molars.

Download Full-text

Correlation Between the Maturation Stages of Mandibular Third Molars and Chronological Age in Patients Visiting Sardar Begum Dental College, Peshawar

Journal of Gandhara Medical and Dental Science ◽

10.37762/jgmds.5-2.79 ◽

2019 ◽

Vol 5 (2) ◽

pp. 3-7

Author(s):

Muhammad Ilyas ◽

Asma Khan ◽

Syed Murad Ali Shah ◽

Salman Khan ◽

Junaid Nadeem Malik

Keyword(s):

Pearson Correlation ◽

Third Molar ◽

Cross Sectional Study ◽

Chronological Age ◽

P Value ◽

Third Molars ◽

Cross Sectional ◽

Mandibular Third Molar ◽

Maturation Stages ◽

Mandibular Third Molars

OBJECTIVES: The objective of this study was to determine the correlation of chronological age with the maturation stages of mandibular third molar. METHODOLOGY: This descriptive, cross-sectional study was conducted at Sardar Begum Dental College, Gandhara University Peshawar on 384 patients from January 2018 to June 2018 and included patients having age 11-26 years with good quality Orthopantomogram showing mandibular third molar tooth germs bilaterally. Data were analyzed using SPSS version 22. p ≤ 0.05 was considered as statistically significant. RESULTS: Females 286 (74.5%) were predominant than males 98 (25.5%) with mean age presentation of 18.12±3.03 years. The most frequent stage of Demirjian’s stages of mandibular third molar was stage F (24.7%). Pearson correlation showed that maturation stages of mandibular third molars were significantly related to the chronological age ( r=0.446, p value=0.00). CONCLUSION: A correlation between maturation stages of mandibular third molars and chronological age existed.

Download Full-text

Automated Prediction of Extraction Difficulty and Inferior Alveolar Nerve Injury for Mandibular Third Molar Using a Deep Neural Network

Applied Sciences ◽

10.3390/app12010475 ◽

2022 ◽

Vol 12 (1) ◽

pp. 475

Author(s):

Junseok Lee ◽

Jumi Park ◽

Seong Yong Moon ◽

Kyoobin Lee

Keyword(s):

Maxillofacial Surgery ◽

Inferior Alveolar Nerve ◽

Third Molar ◽

Oral And Maxillofacial Surgery ◽

Third Molars ◽

Radiographic Image ◽

Common Procedure ◽

Radiographic Images ◽

Mandibular Third Molar ◽

Mandibular Third Molars

Extraction of mandibular third molars is a common procedure in oral and maxillofacial surgery. There are studies that simultaneously predict the extraction difficulty of mandibular third molar and the complications that may occur. Thus, we propose a method of automatically detecting mandibular third molars in the panoramic radiographic images and predicting the extraction difficulty and likelihood of inferior alveolar nerve (IAN) injury. Our dataset consists of 4903 panoramic radiographic images acquired from various dental hospitals. Seven dentists annotated detection and classification labels. The detection model determines the mandibular third molar in the panoramic radiographic image. The region of interest (ROI) includes the detected mandibular third molar, adjacent teeth, and IAN, which is cropped in the panoramic radiographic image. The classification models use ROI as input to predict the extraction difficulty and likelihood of IAN injury. The achieved detection performance was 99.0% mAP over the intersection of union (IOU) 0.5. In addition, we achieved an 83.5% accuracy for the prediction of extraction difficulty and an 81.1% accuracy for the prediction of the likelihood of IAN injury. We demonstrated that a deep learning method can support the diagnosis for extracting the mandibular third molar.

Download Full-text

Prevalence of mandibular third molar impaction pattern in a private dental clinic of Sultanpur Lodhi

International Journal of Health ◽

10.14419/ijh.v3i2.5173 ◽

2015 ◽

Vol 3 (2) ◽

pp. 47

Author(s):

Pushappreet Kaur

Keyword(s):

Third Molar ◽

Third Molars ◽

Radiographic Assessment ◽

Dental Clinic ◽

Impacted Tooth ◽

Mandibular Third Molar ◽

Class 1 ◽

Impacted Mandibular Third Molars ◽

Tooth Number ◽

Mandibular Third Molars

Background: Mandibular third molar is the most commonly impacted tooth, and its removal is a frequently performed dentoalveolar procedure. It is important to know the prevalence rate in a particular community.Objective: This article aims at evaluation of angulation, ramus relationship and depth of impacted mandibular third molars among patients visiting a private dental clinic in Sultanpur Lodhi.Methodology: 150 patients presenting with 228 cases of lower third molar impaction were included within this study. IOPAR and where necessary, OPG was used for radiographic assessment. Age, sex and tooth number were recorded in each patient on a specially designed performa. Angulation was determined using winter’s method whereas assessment of ramus relationship and depth was done using Pell and Gregory's method.Results and Conclusion: The age of patients ranged from 21-43 years with mean age of 26.6 years. Males showed preponderance to mandibular M3 impaction (54%) in our study, and right side was found more frequently involved (53%). Radiographic assessment revealed that mesioangular impaction (45.2%) was the most prevalent angular pattern followed by vertical, distoangular and horizontal types, and Class 2 Position A (29.4%) most common and Class 1 Position C the least common type of impaction depth and ramus relationship.

Download Full-text

An Analysis of Dentigerous Cysts Developed around a Mandibular Third Molar by Panoramic Radiographs

Dentistry Journal ◽

10.3390/dj7010013 ◽

2019 ◽

Vol 7 (1) ◽

pp. 13 ◽

Cited By ~ 4

Author(s):

Masahiko Terauchi ◽

Satoshi Akiya ◽

Junya Kumagai ◽

Yoshio Ohyama ◽

Satoshi Yamaguchi

Keyword(s):

Dentigerous Cyst ◽

Third Molar ◽

Odontogenic Cysts ◽

Third Molars ◽

Class Iii ◽

Panoramic Radiographs ◽

Mandibular Third Molar ◽

Dentigerous Cysts ◽

Panoramic Images ◽

Mandibular Third Molars

Dentigerous cysts are one of the most prevalent types of odontogenic cysts and are associated with the crown of an unerupted tooth, especially of the mandibular third molar. In this study, the characteristics of a dentigerous cyst developed around a mandibular third molar on panoramic radiographs were investigated. The panoramic images of 257 consecutive dentigerous cyst cases associated with a mandibular third molar were analyzed. The mean age of the patients was 45.9 ± 13.3 years. The size of the cyst did not significantly correlate to the age of the patient. The unilocular type (89.1%) and the crown side type (68.5%) were significant. The associated mandibular third molars had a high frequency of class III (64.6%) and position B (48.3%) in Pell and Gregory classification and of horizontal position (36.3%) in angulation. Dentigerous cysts were thought to originate and grow commonly around deeply impacted third molars. The associated third molar with dentigerous cyst tends to have a mesial inclination. Dentigerous cysts do not appear to develop gradually after the crown formation has finished, but arise at various periods randomly.

Download Full-text

Effect of premolar extraction on mandibular third molar impaction in young adults

The Angle Orthodontist ◽

10.2319/101712-814.1 ◽

2013 ◽

Vol 83 (4) ◽

pp. 572-577 ◽

Cited By ~ 18

Author(s):

Çağrı Türköz ◽

Çağrı Ulusoy

Keyword(s):

Therapy Group ◽

Third Molar ◽

Third Molars ◽

Skeletal Class ◽

Premolar Extraction ◽

The Third ◽

Orthodontic Therapy ◽

Extraction Therapy ◽

Mandibular Third Molar ◽

Mandibular Third Molars

ABSTRACT Objective: To test the null hypothesis that orthodontic therapy with or without premolar extraction does not result in any difference in third molar impaction. Materials and Methods: Two groups were formed: 22 patients in one group with first premolar extractions and 22 patients in the other group without extractions. All patients were nongrowing subjects who had normal gonial angles and were skeletal Class I at the beginning of treatment. The available space for third molars, inclination of second and third molars, and angle between the second and third molars were evaluated. Also, the correlation of measured parameters and type of orthodontic therapy with the eruption of third molars was evaluated. Results: Of the third molars, 81.8% were impacted in the nonextraction group and 63.6% were impacted in the extraction group. Impaction of mandibular third molars was significantly correlated to the pretreatment and posttreatment inclination of third molars and the angle between the second and third molars. In the extraction therapy group, the retromolar distance increased significantly with a mean of 1.30 ± 1.25 mm. Conclusions: When the inclination of the third molar is inconvenient, the tooth may remain impacted even if there is enough retromolar space.

Download Full-text

Pattern of Impacted Mandibular Third Molar Teeth in Rangpur Region, Bangladesh: A Radiological Evaluation

KYAMC Journal ◽

10.3329/kyamcj.v12i1.53360 ◽

2021 ◽

Vol 12 (1) ◽

pp. 8-13

Author(s):

Md Rubayet Alam Prodhan ◽

Md Shahidul Islam ◽

Rifat Rezwana ◽

Md Moynul Hasan

Keyword(s):

Third Molar ◽

Third Molars ◽

Radiographic Assessment ◽

Impacted Tooth ◽

Panoramic Radiographs ◽

Impacted Mandibular Third Molar ◽

Mandibular Third Molar ◽

Molar Teeth ◽

Impacted Mandibular Third Molars ◽

Mandibular Third Molars

Background: Third molar is the most commonly impacted tooth in the oral cavity and accounts for large of all impactions. The most common complication in the extraction of the third mandibular molars is nerve and vessels damage. Therefore, thorough radiographic assessment is a necessary to avoid these surgical complications. Objective: The purpose of this study was to evaluate the frequency, angulation, depth of the impacted mandibular third molars and its relationship with ramus on radiographs. Materials and Methods: This study comprised 800 orthopantomograms (OPGs) of patients attending different dental clinics and hospitals in Rangpur region, Bangladesh between June 2014 to May 2015. Panoromic Radiographic assessment was carried out to evaluate the pattern of third molar impaction in terms of age, gender, angulation of impaction, level of eruption and available retromolar space using panoramic radiographs and Pell & Gregory classification. Results: A total of 314 radiographic third molar areas were found in this study, out of them 137 belong to male patients and 177 belong to the female patients. The mesio angular types of angulation was most prevalent (46%) whereas distoangular was rare (5%) in our study. In relation to anterior border of the ramus of mandible Level B 52% and Class II 59% were the most common pattern of impaction. The female tends to be dominant as compared to male & the maximum number (35%) of impacted third molars are found in an age group of 38 years and above. Conclusion: Panoramic radiographs can be used as reliable investigation for evaluation of impacted mandibular third molar. KYAMC Journal.2021;12(01): 08-13

Download Full-text