A retrospective cohort study on reasons to retain third molars

Radiographic Evaluation Factors That Influence the Decision of the Tooth Extraction Method

INTRODUCTION

A simple tooth extraction method usually involves using elevators and forceps to remove the tooth easily. In contrast, a surgical extraction method requires utilizing a straight handpiece to facilitate the tooth extraction, either removing bone or sectioning the tooth into pieces.

OBJECTIVE

In this research, we aim to diagnose a tooth radiographically before extraction and determine certain factors to observe which extraction method might be more feasible, either simple or surgical.

METHODOLOGY

This study followed a retrospective cross-sectional study design. The x-ray radiographs (periapical (PA) or panoramic) were collected from the R4 system in the university dental hospital for data collection. Different radiographic influencing factors were measured, such as bone density, bone level, endodontic involvement (RCT/post and core), crowned or remaining root, and root morphology. Statistical associations were performed using SPSS (IBM Corp., Armonk, NY) with a one-way ANOVA test.

RESULTS

There were 62 cases with 47 simple and 15 surgical extractions. There was a non-significant (p>0.05) association between the measured factors and the extraction method, either simple or surgical tooth extraction. Although bone density measurements showed a slight tendency toward PA lesions and simple tooth extraction.

CONCLUSION

There was no significant association between the factors and extraction methods. Future research is required to determine whether or not preoperative radiographic evaluation can influence the decision for the tooth extraction method.

Transcriptome Sequencing of Gingival Tissues from Impacted Third Molars Patients Reveals the Alterations of Gene Expression

OBJECTIVE

The removal of impacted third molars by surgery may occur with a series of complications, whereas limited information about the postoperative pathogenesis is available. The objective of this study is to identify changes in gene expression after flap surgical removal of impacted third molars and provide potential information to reduce postoperative complications.

METHODS

The gingival tissues of twenty patients with flap surgical removal of impacted third molars and twenty healthy volunteers were collected for gene expression testing. The collected gingival tissues were used RNA sequencing technology and quantitative real-time PCR validation was performed. DEG was mapped to protein databases such as GO and KEGG for functional annotation and, based on annotation information, for mining of differential expression genes in patients with mpacted third molars.

RESULTS

A total of 555 genes were differentially expressed. Among the top up-regulated genes, HLA-DRB4, CCL20, and CXCL8 were strongly associated with immune response and signal transduction. Among the top down-regulated genes, SPRR2B, CLDN17, LCE3D and LCE3E were related to keratinocyte differentiation, IFITM5, and BGLAP were related to bone mineralization, UGT2B17 is associated with susceptibility to osteoporosis. KEGG results showed that the DEGs were related to multiple disease-related pathways.

CONCLUSION

This first transcriptome analysis of gingival tissues from patients with surgical removal of impacted third molars provides new insights into postoperative genetic changes. The results may establish a basis for future research on minimizing the incidence of complications after flap-treated third molars.

Tomographic analysis of relationship of mandibular morphology and third molars eruption

BACKGROUND

Lower third molars (L3M) are the last teeth to erupt in the oral cavity. Uneruption of these teeth still raises questions about its causes, in the literature (1) genetic factors, (2) dental lamina activity and, mainly, (3) insufficient growth and development of the bone bases are included. While the lack of space theory influenced by mandibular morphology and size of L3M was argued to be the main reason for L3M impaction, there is a limitation in the literature in examining such association using more accurate tomographic analysis obtained from CBCT. This work aimed to evaluate the relationship between mandibular morphology and the eruption of L3M.

METHODS

In this regard, 85 Cone Beam Computed Tomographies (CBCT), with 147 L3M, were selected from the archives of the Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, obtained using an Accuitomo® Morita device and using the Dolphin Imaging 11.9 software. L3M eruption was related to linear measurements of jaw length (Co-Gn), retromolar space dimension (D2R), mesiodistal width of the L3M crowns, mandibular first molars (L1M) and mandibular canines (LC) and the angle mandibular (Ar-Go-Me). Independent samples t-test, chi-square tests and logistic regression were performed adopting a significance level of 5%.

RESULTS

The average mandible length of 116.446 mm + 6.415 mm, retromolar space of 11.634 mm + 2.385 mm, mesiodistal size of the L3M of 10.054 mm + 0.941 mm, sum of the mesiodistal widths of the L1M and LC of 15.564 mm + 1.218 mm and mandibular angle of 127.23° + 6.109. There was no statistically significant association between these factors and the eruption.

CONCLUSION

With the results obtained in this study, we conclude that the length and angle of the mandible, teeth size and dimension of the retromolar space are not associated with the L3M eruption.

Diagnostic Aspects of an Included Third Molar in an 88-Year-Old Patient: A Case Report and Literature Review

Included third molars in elderly patients are quite rare in dental practice, and therefore easily misdiagnosed, because these teeth are usually extracted in youth. Additional challenges to correctly diagnosing such a dental condition, and its associated complications, arise from frequent co-morbidities in elderly patients, and from difficult communication with the patient. We report a case of an 88-year-old female patient, who presented in the dental emergency room complaining of a discomfort caused by the sharp edges of her lower incisors, and requesting their extraction; the final diagnosis, of suppurated pericoronitis at tooth 48, was concluded based on the clinical elements and X-ray examination.

Midfacial development and the wisdom of teeth: A case series

The alignment of third molars has largely been overlooked by orthodontists. Since difficulties arise during their eruption, a plethora of surgical procedures is advocated for their management, including prophylactic extraction. This case series describes the use of midfacial development in 4 patients and illustrates successful patterns of third molar eruption.

Third molar extraction in middle-aged and elderly patient

Extraction of impacted third molars is a routine procedure performed by oral and maxillofacial surgeons. However, extractions in middle-aged or elderly individuals are not easy, and there are several factors that need to be considered. These factors include decreased healing potential and the risk of complications increasing with age. In addition, third molars can often be fully or deeply impacted in middle-aged individuals, and pathologic changes, such as cysts, caries, or periodontitis of the adjacent second molar, can develop. Furthermore, the rate of ankylosis and systemic disease increases after middle age. It is considered that these factors acting alone or in combination increase the difficulty of extraction.

Comparison of the third molar maturity index (I3M) between left and right lower third molars to assess the age of majority: a multi-ethnic study sample

The diagnostic accuracy of the I_3M to assess the legal age of 18 years has already been tested in several specific-population samples. The left lower third molar has been extensively used for discriminating between minors and adults. This research aimed to compare the usefulness of lower third molar maturity indexes, from both left and right side (I_3ML and I_3MR), in samples originating from four distinct continents in order to examine possible differences in their accuracy values. For this purpose, a sample of 10,181 orthopantomograms (OPGs), from Europe, Africa, Asia and America, was analysed and previously scored in other studies. The samples included healthy subjects with no systemic disorders with both third molars and clear depicted root apices. Wilcoxon Signed Rank test for left and right asymmetry did not show any significant differences. Data about sensitivity, specificity, predictive values, likelihood ratio and accuracy were pooled together and showed similar results for I_3ML and I_3MR, respectively. In addition, all these quantities were high when only the I_3MR was considered to discriminate between adults and minors. The present referable database was the first to pool third molar measurements using panoramic radiographs of subjects coming from different continents. The results highlighted that both I_3ML and I_3MR are reliable indicators for assessing the legal age of 18 years old in those jurisdictions where this legal threshold has been set as the age of majority.

[Characterization of third molar extraction]

The aim of this study was to characterize the main indications, contraindications and prophylactic actions for third molar extraction according to the literature. The Pubmed, Scopus and Web of Science databases were searched using a total of 3 search keys, including publications up to 5 years old, in English or Spanish, with availability of full text. Eighteen articles were selected and showed that the most frequent indication for third molar extraction was the diagnosis of pericoronaritis, followed by distal cervical caries in the lower second molar, and root resorption in adjacent teeth and cysts. In turn, it may be indicated to facilitate other types of dental treatment, such as orthodontics, orthognathic surgery and rehabilitation. In relation to contraindications, the risk of intraoperative complications was associated with the inferior alveolar nerve, advanced age and the predomination of systemic involvement. Prophylactic extraction was included in the analysis in 72.2% of the articles, with a predominance of exodontia of asymptomatic and disease-free third molars. Finally, there are clear indications and contraindications for third molar extraction, being mainly associated with pathological changes, indications for orthodontic treatment, orthognathic surgery and rehabilitative treatment. However, there is controversy in the literature regarding prophylactic extraction, emphasizing that not all retained and asymptomatic third molars should be extracted. Third molar extraction should be evaluated on a case by case basis, considering the benefits, the patient's characteristics and the risk of postoperative complications.