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

Demographic and Radiographic Characteristics Associated with the Occurrence of Impacted Third Molars in Indonesian Patients: A Retrospective Study

An impacted third molar is one of the most common abnormalities of the tooth position, impacting patients and their quality of life. Based on the impact and the invasive removal procedure, this study aimed to evaluate the characteristics of impacted third molars based on their radiographic features as well as their association with demographic characteristics. Outpatient dental records of the oral and maxillofacial surgery department of Hasan Sadikin Hospital, Bandung, Indonesia, from 1 January 2018 to 31 December 2019, were sorted, and relevant clinical and demographic data and panoramic radiographic examination results were extracted from these records. All data were then tabulated and analyzed by using SPSS version 29. As many as 3019 impacted third molars were identified. Our findings suggested the association between age to the occurrence of impacted third molars where patients aged between 17 and 29 years old showed high occurrences of impacted third molars. Male patients with impacted third molars are more likely to have multiple impacted third molars, while this risk decreases in females. Radiographic examination showed that the mesioangular position is the most common position for mandibular third molars. The variation in high occurrences of the impacted third molar is associated with several demographic factors.

Mandibular Third Molar Impaction and Bone Change Distal to the Second Molar: A Panoramic Radiographic Study

Background: The mandibular third molar is the most frequently impacted tooth. An impacted mandibular third molar (IMTM) can have negative consequences on the adjacent mandibular second molar (MSM), such as bone loss. An IMTM can be identified using orthopantomography (OPG). Our objective is to compare changes in bone level distal to the mandibular second molar (MSM) in patients with an extracted IMTM versus non-extracted IMTM using OPG. Methods: In this retrospective case-control study, 160 orthopantomograms (OPGs) of 80 patients who attended Dental Hospital of the University of Barcelona (HOUB) were randomly selected. Participants were stratified into a study group and control group. Results: Males and females experienced bone gain in the study group and bone loss in the control group. However, the difference in bone-level change was not statistically significant regarding gender in the study group. Within the study group, the age group of 29-39 years demonstrated significant (p-value = 0.042) bone gain after extraction compared to other age groups. However, the control group demonstrated bone loss in all age groups in which the difference is not statistically significant (p-value 0.794). Conclusions: Bone improvements distal to the MSM were observed after the extraction of an IMTM compared to when an IMTM was not extracted.

The relationship of the position of mandibular third molar impaction with the development of dental and periodontal lesions in adjacent second molars

OBJECTIVE

The aim of this study was to evaluate the effect of different positions of Mandibular third molar impaction teeth on dental and periodontal lesions of mandibular second molars and correlate the lesion severity with patient age.

MATERIALS AND METHODS

This retrospective study assessed 212 CBCT images of patients who visited the department of Oral and Maxillofacial radiology of XX university between 2017 and 2021. Periodontal and dental lesion effects of impacted third molars on mandibular second molars were evaluated. While dental lesions were classified as mild, moderate, and severe, periodontal lesions were classified as mild in cases not exceeding 2/3 of the root, and severe in cases exceeding 2/3 of the root. Pearson's chi-square tests, Mann-Whitney U or Kruskal-Wallis test were used for data analsis. A multivariate logistic regression model was constructed for further analysis.

RESULTS

Periodontal lesions were frequently observed in the second molar adjacent to the third molar (157 teeth, 74.1%), dental lesions were observed in 10%. Among the third molar positions, the mesioangular position was associated with a high (88%) prevalence of periodontal lesions (p<0.001), followed by the horizontal position (71%). The periodontal lesion was more severe in cases 30-39 years old and over 40 years old than in cases under 20 years old and 21-24 years old. Distoangular, horizontal and vertical/inverse positions are less likely to increase the severity of the periodontal lesion than the mesioangular position. (OR = 0.02; p <0.001, OR = 0.28; p =0.008, OR = 0.14; p <0.001,respectively).

CONCLUSIONS

The third molars are often impacted in the mesioangular position, and this position most increases the risk of periodontal infection in the second molars. Accurate diagnosis and evaluation can minimize complications, and CBCT is a reliable imaging technique in which the position of the third molars and their relationship with the 2nd molars can be evaluated.