The management of mesially inclined/impacted mandibular permanent second molars

Managing Mandibular Second Molar Impaction: A Systematic Review and Meta-Analysis

PURPOSE

Mandibular second molar (M2M) impaction is a serious eruption disorder. The purpose of this systematic review was to analyze the therapeutic approaches for M2M impaction. The objective of the meta-analysis was to summarize the success of the surgical, surgical-orthodontic, and orthodontic treatment.

METHODS

A PRISMA-guided search strategy was conducted by 2 authors in 5 databases up to January 2023. Randomized and nonrandomized clinical trials were considered. Case reports, case series with<5 patients, and reviews were excluded. Methodological quality was assessed using Newcastle-Ottawa scale and Cochrane Collaboration tool for nonrandomized and randomized clinical trials, respectively. Outcomes were as follows: 1) treatment success rate defined by the repositioning of impacted M2M in the dental arch with normal functional occlusal relationship and periodontal health; 2) time-to-repositioning as time-to-event analysis; and 3) complications. Meta-analysis examined treatment success differences with 3 approaches: orthodontic (uprighting maneuvers/traction), surgical (surgical procedures/strategic extractions), and surgical-orthodontic (combined surgical and orthodontic procedures) as the exposure variable. The quantitative analysis also compared the success rate using third molar removal as the secondary predictor variable. The χ2 test determined the statistical heterogeneity (I2); a cut-off of 70% was used to select the common or random effects model. Odds ratio (OR) and 95% confidence interval (CI) were recorded.

RESULTS

A total of 1,102 articles were retrieved. After full-text reading, 16 articles were included and 1008 M2Ms were analyzed. Nine studies had fair quality, 6 studies had good quality, and 1 had unclear risk of bias. Managing impacted M2Ms showed a moderate to high success rate (66.7 to 100%). Significant differences favoring surgical treatment over orthodontic treatment were observed for M2M uprighting (OR = 4.97; CI: 1.49 to 16.51; P = .01).No differences were detected comparing surgical and surgical-orthodontic treatment (OR = 1.00; CI: 0.03 to 37.44; P = .99), or orthodontic and surgical-orthodontic treatment(OR = 4.14; CI: 0.43 to 40.14; P = .22).Third molar removal showed no significant correlation with M2M uprighting (OR = 1.98; CI: 0.24 to 16.03; P = .5).

CONCLUSION

Despite study limitations, both orthodontic and surgical management of impacted M2M can be effective suggesting that clinicians are able to choose best treatment for most cases.

Surgical Treatment of Impacted Mandibular Second Molars: A Systematic Review

PURPOSE

The evidence on surgical uprighting and surgical exposure for the management of impacted mandibular second molars is limited. This systematic review evaluated the efficacy of both of these surgical procedures in the management of impacted mandibular second molars.

METHODS

The authors conducted a systematic review without meta-analysis of English language articles on Pubmed and Embase databases without publication date restrictions. Additional studies were identified by searching reference lists and manually reviewing published literature in key journals. Potential included study types were cases series, cohort studies, and randomized clinical trials studying surgical uprighting or surgical exposure of impacted mandibular second molars. The outcomes studied were the positioning of the tooth in the dental arch, pulpal obliteration or calcification, infection, root resorption, and root fracture.

RESULTS

Of the 1,438 records identified, 8 were included in the review, representing a total of 433 molars. The age of study participants in the included studies ranged from 7 to 20 years. A total of 22 of 27 (81.5%) impacted mandibular second molars included in this study were reported to be successfully positioned in the dental arch after surgical exposure. A total of 374 of 408 (91.7%) mandibular second molars included in this study were successfully positioned in the dental arch after surgical uprighting. There were no reported cases of infection and root fracture of impacted mandibular second molars treated by surgical exposure. In surgical uprighting, the overall reported rates of pulpal obliteration or calcification, infection, root resorption, and root fracture were 27.1, 1.9, 14.9, and 1.0%, respectively.

CONCLUSIONS

While there are few studies comparing treatment strategies for the management of impacted mandibular second molars, surgical uprighting appears to be a successful treatment option for these patients with few reported complications.