(10) Consideration About the Causes and Influencing Factors of Mandibular Third Molar Extractions in Elderly Patients

Abstract: Statements of the problem
The impacted third molar can cause many pathological conditions, therefore, for young patients, extraction is often considered the treatment of choice for impacted lower third molars. But, Imprudent extraction of deeply impacted third molars can cause permanent complications, guidelines for the extraction of lower third molars should be set to prevent embarrassing complications.
In this study, we investigated the causes of the mandibular third molar extractions in elderly patients. And we analyzed the relationship between the impaction patterns and their pathologic conditions that have occurred. So we want to help you decide whether to extract or not by predicting pathological findings that may occur in the future.

Materials and methods
1) Data collection
: Pathologic conditions that caused tooth extraction were investigated through data analysis
2) Classification of the impacted third molar
: The impacted mandibular third molar was evaluated based on the panoramic x-ray analysis for three major parameters: spatial relationship(angulation), depth, and ramus space. (Fig 1,2,3.)
3) Analysis of deep impacted third molar
: For deep impacted teeth(Depth level C or D), Passage connecting the impacted teeth and the oral cavity was investigated through x-ray and CT analysis.
4) Statistical analysis
: Chi-square test was used to analyze the relationship between impaction patterns and the pathologic conditions of impacted third molar.

Results of investigation & Outcomes data
1. Pathologic conditions that caused tooth extraction
The most common pathologic condition was infection (pericoronitis) (N=84, 37.33%). and extractions by patient’s needs were the second most (N=41,18.22%).
Extractions by adjacent teeth caries and local periodontitis including adjacent were found to be 35(15.56%) and 23(10.22%), respectively. Among them, 20(8.73%) were diagnosed with hopeless tooth and adjacent teeth were extracted concurrently.
2. The relationship between impaction patterns and the pathologic conditions
As a result of chi-square test, spatial relationship (angulation) and ramus space did not show a significant correlation with pathologic conditions.

Outcomes data
In this study of middle-aged and older adults, most of impacted third molars (81.8%) were extracted with various pathologic conditions. 26% of cases were accompanied with pathologic adjacent teeth disease such as caries and local periodontitis, and there were a number of cases that adjacent teeth were extracted concurrently. Bruce et al. reported that the frequency of complications (pain, edema, nerve damage, etc.) after extraction was increased depending on the age.
In this study, a lot of pathologic conditions (84%) appeared in shallow impacted teeth (Level A and B). In deep impacted teeth (Level C, D), the proportion of local periodontitis was relatively high. Analyzing these teeth, a passage connecting the impacted and the oral cavity was observed in the alveolar bone. It is thought that the intrusion of foreign bodies through this passage and deposition of sub-gingival calculus may be the cause of the disease.

Conclusions relevant to the problem
Therefore, considering prevention of adjacent tooth disease and complications, it would be advantageous to perform impacted extraction at the young age. And, even in the case of deep impacted teeth, extraction is recommended to prevent pathologic conditions when the passage leading to impacted teeth is identified on panoramic view or CT images.

List of two references
1. Kim, J. Y., Yong, H. S., Park, K. H., & Huh, J. K. (2019). Modified difficult index adding extremely difficult for fully impacted mandibular third molar extraction. Journal of the Korean Association of Oral and Maxillofacial Surgeons, 45(6), 309-315.
2. Nazir, A., Akhtar, M. U., & Ali, S. (2014). Assessment of different patterns of impacted mandibular third molars and their associated pathologies. J Adv Med Dent Sci Res, 2(2), 14-22.

Characteristics of included patients


Pathologic conditions that caused tooth extraction

Relationship between depth of impacted molar and pathologic conditions