Peer Review #1 of "Third molar agenesis in modern humans with and without agenesis of other teeth (v0.1)"

Abstract Background The number of teeth in the human dentition attracts special interest both from developmental and evolutionary aspects. The present case-control study focused on the formation of third molars in modern humans aiming to shed more light in this long lasting enigma.Methods For this reason, we investigated third molar formation in a sample of 303 individuals with tooth agenesis other than in third molars (agenesis group) and compared it to a sex and age matched control group of 303 individuals without tooth agenesis other than in third molars.Results The prevalence of third molar agenesis in the agenesis group was 50.8%, which is significantly higher than the 20.5% in the control group (p < 0.001). The chance of a missing third molar in the agenesis group was increased by 38.3% (p < 0.001), after controlling for the other tooth agenesis factor. When considering the percentages of the number of missing third molars per individual, a clear tendency towards more missing third molars was evident in the agenesis group compared to the control group. The frequency of bilaterally missing third molars in the agenesis group was 29% in the upper as well as in the lower jaw, which is about three times higher than the frequency of unilaterally missing third molars (p < 0.001). In the control group, bilaterally missing third molars occurred in 8.6% in the upper and 8.9% in the lower jaw.Conclusion The present results indicate that genetic factors involved in certain tooth agenesis also affect the entire dentition as a whole. Furthermore, the third molars are more vulnerable to factors involved in other tooth agenesis and they are more often affected as a total. These findings seem to be associated with the evolutionary trend in humans towards reduced molar number.

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Third molar agenesis in modern humans with and without agenesis of other teeth

PeerJ ◽

10.7717/peerj.10367 ◽

2020 ◽

Vol 8 ◽

pp. e10367

Author(s):

Maya Scheiwiller ◽

Elias S. Oeschger ◽

Nikolaos Gkantidis

Keyword(s):

Case Control Study ◽

Matched Control ◽

Third Molar ◽

Control Group ◽

Evolutionary Trend ◽

Third Molars ◽

Modern Humans ◽

Third Molar Agenesis ◽

Evolutionary Aspects ◽

Control Study

Background The number of teeth in the human dentition is of interest both from developmental and evolutionary aspects. The present case-control study focused on the formation of third molars in modern humans aiming to shed more light on the most variable tooth class in the dentition. Materials and Methods For this reason, we investigated third molar formation in a sample of 303 individuals with agenesis of teeth other than third molars (agenesis group) and compared it to a sex and age matched control group of 303 individuals without agenesis of teeth other than third molars. Results The prevalence of third molar agenesis in the agenesis group was 50.8%, which is significantly higher than the 20.5% in the control group (p < 0.001). The chance of a missing third molar in the agenesis group was increased by 38.3% (p < 0.001), after controlling for the agenesis in other teeth factor. When considering the amount of missing third molars per individual, a clear tendency towards more missing third molars was evident in the agenesis group compared to the control group. The frequency of bilaterally missing third molars in the agenesis group was 29% in the maxilla, as well as in the mandible, which is about three times higher than the frequency of unilaterally missing third molars (p < 0.001). In the control group, bilaterally missing third molars occurred in 8.6% in the maxilla and 8.9% in the mandible. Conclusion The present results indicate that genetic factors involved in tooth agenesis affect also the dentition as a whole. Furthermore, the third molars are more vulnerable to factors involved in agenesis of other teeth and they are more often affected as a whole. These findings seem to be associated with the evolutionary trend in humans towards reduced molar number.

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Third molar agenesis in modern humans with and without agenesis of other teeth

10.21203/rs.2.15532/v2 ◽

2020 ◽

Author(s):

Maya Scheiwiller ◽

Elias S. Oeschger ◽

Nikolaos Gkantidis

Keyword(s):

Case Control Study ◽

Matched Control ◽

Third Molar ◽

Control Group ◽

Evolutionary Trend ◽

Third Molars ◽

Modern Humans ◽

Third Molar Agenesis ◽

Evolutionary Aspects ◽

Control Study

Abstract Background The number of teeth in the human dentition is of interest both from developmental and evolutionary aspects. The present case-control study focused on the formation of third molars in modern humans aiming to shed more light on the most variable tooth class in the dentition. Methods For this reason, we investigated third molar formation in a sample of 303 individuals with agenesis of teeth other than third molars (agenesis group) and compared it to a sex and age matched control group of 303 individuals without agenesis of teeth other than third molars. Results The prevalence of third molar agenesis in the agenesis group was 50.8%, which is significantly higher than the 20.5% in the control group (p < 0.001). The chance of a missing third molar in the agenesis group was increased by 38.3% (p < 0.001), after controlling for the agenesis in other teeth factor. When considering the amount of missing third molars per individual, a clear tendency towards more missing third molars was evident in the agenesis group compared to the control group. The frequency of bilaterally missing third molars in the agenesis group was 29% in the maxilla, as well as in the mandible, which is about three times higher than the frequency of unilaterally missing third molars (p < 0.001). In the control group, bilaterally missing third molars occurred in 8.6% in the maxilla and 8.9% in the mandible. Conclusion The present results indicate that genetic factors involved in tooth agenesis affect also the dentition as a whole. Furthermore, the third molars are more vulnerable to factors involved in agenesis of other teeth and they are more often affected as a whole. These findings seem to be associated with the evolutionary trend in humans towards reduced molar number.

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The relation between third molar agenesis and craniofacial morphology

Egyptian Orthodontic Journal ◽

10.21608/eos.2012.78823 ◽

2012 ◽

Vol 42 (12) ◽

pp. 51-64

Author(s):

Nagwa Enany ◽

Ahmed El-Kalza ◽

Fatma El-Shikhy

Keyword(s):

Third Molar ◽

Craniofacial Morphology ◽

Third Molar Agenesis

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Inferior alveolar nerve block and third-molar agenesis

The Journal of the American Dental Association ◽

10.14219/jada.archive.2013.0132 ◽

2013 ◽

Vol 144 (4) ◽

pp. 389-395 ◽

Cited By ~ 5

Author(s):

Jerry Swee ◽

Anthony R. Silvestri ◽

Matthew D. Finkelman ◽

Alfred P. Rich ◽

Stanley A. Alexander ◽

...

Keyword(s):

Nerve Block ◽

Inferior Alveolar Nerve ◽

Third Molar ◽

Inferior Alveolar Nerve Block ◽

Third Molar Agenesis

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HISTOLOGIC AND RADIOGRAPHIC STUDY OF PATHOLOGIC CHANGE IN COMPLETE IMPACTED THIRD MOLARS DENTAL FOLLICLES

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v6i1.539 ◽

2021 ◽

Author(s):

Shafiqa Mohammed Haidra Masdoose ◽

Akram Thabet Nasher ◽

Monya A. El-Zine ◽

Ameen Abdullah Yahya Al-Akwa ◽

Hassan Abdulwahab Al-Shamahy ◽

...

Keyword(s):

Peer Review ◽

Dentigerous Cyst ◽

Third Molar ◽

Inflammatory Cells ◽

The United States ◽

Age Group ◽

Histopathological Changes ◽

Histological Changes ◽

Impacted Third Molar ◽

Younger Age

Background: Prophylactic extraction of the asymptomatic impacted third molar is routinely practiced in Europe and the United States. The justification for prophylactic extraction includes the need to reduce the risk of pathologic changes such as cysts and tumors. Objectives: This study aimed to study the histological and radiological changes in the tooth follicles of upper and lower complete impacted 3rd molars -which appeared radiologically normal. Material and method: A prospective study included fifty patients aged 20 years and above who were referred to the Oral Surgery Clinic, Faculty of Dentistry, University of Sana'a. Patients had follicular space between (2.5mm -3mm) as measured by the panoramic X-ray. These teeth were removed surgically and the follicle was sent for histopathological examination. Results: Most histopathological changes were in dental follicles with a size of <2.5 mm (86%), and only 14% with 2.5 mm - 3 mm. There was statistical significance between the smallest size of dental follicles with the incidence of pathological histological changes indicating a high probability of developing neoplasm (p =0.008). Of the 50 follicular patients, 28% showed HC, nine (64%) had ameloblastoma, four (29%) had a dentigerous cyst, and only one case (7%) had a multicalcified focus with islands of odontogenic epithelium. While 72% of the samples had normal follicles and non-specific chronic inflammatory cells. There is an association between female sex and pathological histological changes (12 females: 2 males, p =0.008), age group 21-25 years (93% HC), with mandibles (65% HC). Regarding angle and histopathological changes, 36% were vertical, 29% mesioangular, 14.2% horizontal and destioangular, and 7.1% buccoangular. Conclusion: High incidence of HC occurred in patients with DF, and it was associated with smaller dental follicle size, most HC was ameloblastoma, followed by dentigerous cyst, while 72% of samples had normal follicles and non-specific chronic inflammatory cells. There is a correlation between female gender, younger age group, and jaw position with HC. Prophylactic extraction of the asymptomatic impacted third molar should be routinely practiced in Yemen, to reduce the risk of pathological changes, especially in females and younger age groups. Peer Review History: Received 11 January 2021; Revised 8 February; Accepted 28 February, Available online 15 March 2021 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 7.5/10 Reviewer(s) detail: Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, [email protected] Dr. Alfonso Alexander Aguileral, University of Veracruz, Mexico, [email protected] Similar Articles: RADIOGRAPHIC ASSESSMENT OF THE COURSE AND VISIBILITY OF THE MANDIBULAR CANAL BY PANORAMIC RADIOGRAPHY

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Relationship between skeletal malocclusion and dental anomalies in Nepalese population

Orthodontic Journal of Nepal ◽

10.3126/ojn.v9i1.25684 ◽

2019 ◽

Vol 9 (1) ◽

pp. 15-18

Author(s):

Bashu Dev Pant ◽

Anjana Rajbhandari ◽

Resina Pradhan ◽

Manju Bajracharya

Keyword(s):

Third Molar ◽

Class Ii ◽

Class I ◽

Class Ii Malocclusion ◽

Class Iii ◽

Dental Anomalies ◽

Chi Square ◽

Skeletal Class ◽

Skeletal Malocclusion ◽

Third Molar Agenesis

Introduction: Teeth eruption is important for the development of alveolar process which increases vertical height of the face and third molar is the last tooth to erupt in the oral cavity after birth. The aim of this study was to determine relationship between skeletal malocclusion and dental anomalies in Nepalese population. Materials & Method: A sample of 170 patients with agenesis of at least one third molar was divided into four groups according to the third-molar agenesis pattern. Panoramic radiographs, lateral cephalograph and cast models were used to determine the skeletal malocclusion and associated dental anomalies. The Pearson chi-square test was used for stastical analysis. Result: Among 170 patients more than half of the patients were female with the average age being 18.15 ± 3.64 years. Majority of the patients had Class I skeletal malocclusion followed by Class II and III but on group wise comparison of patients with different skeletal patterns Class I skeletal malocclusion had highest prevalence of dental anomalies followed by Class III and Class II malocclusion. Conclusion: Prevalence of third-molar agenesis was more in skeletal class I malocclusion followed by class II and III but skeletal Class I malocclusions had more dental anomalies followed by class III and class II malocclusion.

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