Pathologies associated with the mandibular third molar impaction

Risk factors associated with the severity of pericoronitis of mandibular third molar

PURPOSE

The factors related to pericoronitis severity are unclear, and this study aimed to address this knowledge gap.

MATERIALS AND METHODS

In total, 113 patients with pericoronitis were included, and their demographic, clinical, and radiographic characteristics were recorded. The Patient-Clinician Pericoronitis Classification was used to score and categorize the severity of pericoronitis. Statistical analysis was conducted to examine the participants' characteristics, validity of the Patient-Clinician Pericoronitis Classification, and risk factors associated with the severity of pericoronitis.

RESULTS

The demographic, clinical, and radiographic characteristics of males and females were similar, except for Winter's classification, pain, and intraoral swelling. The constructive validity of the Patient-Clinician Pericoronitis Classification was confirmed with three latent factors, including infection level, patient discomfort, and social interference. Ordinal logistic multivariate regression analysis revealed that upper respiratory tract infection was the sole risk factor associated with pericoronitis severity in males (odds ratio = 4.838). In females, pericoronitis on the right side (odds ratio = 2.486), distal radiolucency (odds ratio = 5.203), and menstruation (odds ratio = 3.416) were significant risk factors.

CONCLUSION

This study demonstrated the constructive validity of the Patient-Clinician Pericoronitis Classification. Among females, pericoronitis in mandibular third molars on the right side with radiolucency in menstruating individuals was more severe. In males, upper respiratory tract infection was the sole risk factor associated with pericoronitis severity.

CLINICAL RELEVANCE

Individuals with risk factors should be aware of severe pericoronitis in the coming future.

Role of αENaC in root resorption of adjacent teeth due to entirely impacted mandibular third molars

BACKGROUND

Entirely impacted mandibular third molar (EIM3M) concerns the pathological external root resorption (ERR) of the adjacent mandibular second molar (M2M) and formation of granulation tissue between two molars. The study aimed to clarify the effect of αENaC, a mechano-sensitive molecule, to explore the mechanical mechanism in this scenario.

METHODS

The force EIM3M exerted on M2M was proved by finite element analysis. αENaC expressions were tested by real-time polymerase chain reaction (PCR), immunoblotting and immunofluorescence. Inflammatory and epithelial-mesenchymal transition (EMT)-related molecules expressions were also detected by real-time PCR. The correlation was analyzed by Spearman's correlation analysis, and receiver-operator characteristic (ROC) curve was further exhibited.

RESULTS

The force was concentrated in the ERR area. αENaC was upregulated, positively correlated with ERR degree and localized to the fibroblasts in ERR granulation tissues. Moreover, αENaC was respectively and positively associated with elevated TNF-α and N-cadherin in ERR granulation tissues. More importantly, ROC analysis verified αENaC as a novel indication of the incidence of this disease.

CONCLUSIONS

Our finding revealed the force from EIM3M causing ERR of M2M, and elucidated the expression and localization of αENaC and its positive correlation with inflammation, EMT and disease severity, suggesting a novel indication in this disease.

The Accuracy of Bone Assessment Distal to Lower Second Molars Using Panoramic Radiography: A Systematic Review and Meta-Analysis

Panoramic radiography (OPG) evaluates mandibular third molar impaction (MTMI). This systematic review aimed to investigate the diagnostic accuracy of OPG in detecting bone loss distal to the lower second molars. The associated bone loss with different impaction positions and the most prevalent positions of MTMI were investigated as secondary outcomes. In January 2023, PubMed, Scopus, and Cochrane were searched to identify studies published between January 2012 and January 2023. Two examiners blindly selected the eligible studies for data extraction and quality assessment. Of 427 studies, 8 were suitable for data extraction. All studies reported bone loss distal to the second molar using OPG, ranging from 4.9 to 62.9%. The most frequent position of MTMI is mesioangular. The distal bone loss in the vertical and horizontal positions is statistically significant compared to typically positioned third molars and those that are fully erupted or impacted, but in a normal orientation (p-value 0.005 and 0.02, respectively). Bone loss was not statistically significant in the mesioangular position compared to other impacted positions (p-value 0.14). The risk of bias ranges between 66 and 88%. Despite its limitations, OPG is still considered a valuable tool to assess bone loss distal to the lower second molar in cases of an impacted mandibular third molar.

Relationship between the Status of Third Molars and the Occurrence of Dental and Periodontal Lesions in Adjacent Second Molars in the Polish Population: A Radiological Retrospective Observational Study

The aim of this study was to evaluate the effect of third molars on caries, external root resorption, and alveolar bone loss on the distal surface of adjacent second molars. A total of 2488 panoramic radiographs of adult Poles were evaluated. Third molars were classified, according to eruption status, into non-impacted, partially, or completely impacted, and according to angulation into horizontal, mesioangular, vertical, and distoangular. Completely impacted third molars were assigned as reference group. The odds ratios (ORs) and 95% confidence intervals for the occurrence of the above-mentioned pathologies were 1.39 (1.09-2.21), 6.51 (3.72-10.11), and 2.42 (1.22-4.09), respectively, for second molars with adjacent erupted third molars and 1.54 (1.11-2.82), 10.65 (7.81-20.19), and 5.21 (3.38-10.81), respectively, when partially impacted third molars were next to second molars. The ORs of lesions were significantly higher for horizontally and mesioangularly impacted third molars. Within the limitation of a radiological study, it might be concluded that the presence of erupted third molars is a risk factor for caries, while the presence of impacted third molars increases the risk of root resorption and bone loss on the distal surface of second molars.

Astragaloside reduces toxic effect of periodontal ligament fibroblasts induced by lipopolysaccharide

Periodontitis is a non-specific and chronic disease which is highly prevalent, resulting in inflammation and destruction of periodontal tissues. This study aims to explore the effect and mechanism of astragaloside on periodontitis. We used CCK-8, Western Blot, qPCR and flow cytometry to analyze cell viability, related protein and mRNA expression, and cell apoptosis. We found that AST could promote cell proliferation and reduce apoptosis induced by LPS. Besides, AST could alleviate the increased expression of COX-2 and ICAM-1 induced by LPS. MiR-26b-3P specifically targeted the 3' UTR of ICAM-1. These results indicate that AST reduces toxic effect of human periodontal ligament cells through regulating miR-26b-3P/ICAM-1, thus highlighting its protective role in periodontitis.

Patterns of Third-Molar-Pericoronitis-Related Pain: A Morphometrical Observational Retrospective Study

BACKGROUND

Mandibular third molar (M3M) removal and the management of postoperative complications represent a common matter of interest in oral and maxillofacial surgery. Pain represents a great symptom for patients affected by pericoronitis and it is the most common indication for third molar removal. The aim of the present article is to search for patterns of pre-operative pain in patients before undergoing third molar surgery and to test for a relation between some patterns of symptoms, such as pain intensity, site of symptomatic tooth, and referred area of pain.

METHODS

This retrospective observational study enrolled a total of 86 patients, aged (mean ± SD) 34.54 ± 13.62 years (range 17-78 years), scheduled for outpatient third molar extraction at the Oral Surgery School, Department of Medical Biotechnologies, Policlinico "Le Scotte", University of Siena. Pericoronitis and pain were the symptoms of the patients and the indication of extraction. Inclusion criteria were the presence of partially impacted third molars, confirmed with a preoperative panoramic radiograph, and preoperative pain. Exclusion criteria were known neurological disease (such as previous trigeminal or facial nerve injuries), impaired communicative or cognitive disease, diagnosed diabetes mellitus, and oral surgical intervention within 30 days before data collection. Patients were visited and asked to answer a morphometric analytic questionnaire about their perception of pain referred to the third molar. Analyses were performed on statistical evaluation on age, age ranges, patient gender, prior third molar extraction, site of pericoronitis, pain score (1-10), and pain area. Two-tailed p values of less than 0.05 were considered significant if not otherwise specified.

RESULTS

No correlations were found between age, gender, previous extraction, tooth site (maxillar on mandible), pain score, and pain area. Patterns of third molar pericoronitis pain among 86 patients were reported. A significant correlation was found between pain score and pain area (p = 0.0111, r_s = 0.3131).

CONCLUSIONS

Pain intensity has indeed some kind of responsibility in determining the orofacial distribution of pain. The pain area referral patterns of the present article could be considered as a pain model resulting from the pericoronitis of maxillar and mandibular third molars.

The pattern of mandibular third molar impaction and its relationship with the development of distal caries in adjacent second molars among Emiratis: a retrospective study

Objectives

The purpose of this study was to investigate the pattern of mandibular third molar (MTM) impaction and associated carious lesions in adjacent mandibular second molars (MSMs) in a sample of Emirati individuals.

Methods

This retrospective study assessed 2000 orthopantomograms of Emirati patients who visited the Specialized Fujairah Dental Center between 2015 and 2020. The depth, ramus relation and angulation of the impacted MTMs were assessed according to the Pell and Gregory classification and Winter’s classification. In addition, carious lesions in adjacent MSMs associated with the evaluated parameters were identified.

Results

A total of 461 (23.05%) of the patients had at least one impacted MTM. The mean age of the study population was 26.24 years. Mesioangular, level B, and class II impactions were the most common, at 47.37% (χ² = 382.134; p < 0.001), 45.48% (χ² = 56.889; p < 0.001), and 74.05% (χ² = 513.099; p < 0.001), respectively. There was a higher percentage of level C impaction among females than among males (χ² = 19.178; p < 0.001). A total of 126 impacted teeth (18.36%) had associated carious lesions. These carious lesions were predominantly found in teeth with mesioangular impactions (χ² = 59.430; p < 0.001), level A and B impactions (χ² = 23.301; p < 0.001), and class II and I impactions (χ² = 17.918; p = 0.006).

Conclusions

It is imperative to raise awareness of soft tissue mesioangular-impacted MTMs, as they are the most frequently associated with the development of carious lesions in adjacent MSMs. Approximately one quarter of evaluated Emiratis had at least one impacted MTM, with the most prevalent pattern being class II, level B, and mesioangular impactions. Furthermore, surgical removal is expected to be more challenging for females than for males.

Impact of the presence of partially erupted third molars on the local radiographic bone condition

The decision on retaining or prophylactically removing asymptomatic lower third molars is still discussed in the literature. This study aimed to verify the association between asymptomatic lower third molars and local bone conditions through periapical radiographs. Based on sample size calculations, 288 radiographs were required. Dependent variables were alveolar bone crest status and radiolucency between the distal aspect of the third molar crown and the ascending mandibular ramus. Independent variables were sex, age, Pell and Gregory and Winter’s classification, angulation and distance between second and third molars, third molar side. Advanced ages (OR 1.15; CI 1.08–1.24; p < 0.001) and greater third molar angulations (OR 1.03; CI 1.01–1.04; p < 0.001) significantly increased the chance of radiographic alterations in the bone crest between second and third molars. Radiolucency distal to third molars was solely impacted by patient’s age (OR 1.05; CI 1.01–1.11; p = 0.036). Older patients and lower third molars with greater angulations about adjacent second molar should be evaluated for third molar removal because of the increased chance of alveolar bone crest alterations. Older patients should also be monitored for wider radiolucent pericoronal spaces distal to lower third molars and its consequences.