Angulation of Mandibular Third Molars as a Predictive Factor for Pericoronitis

Multivariable Analysis of Correlation Between Anatomical Features of Mandibular Third Molars and Pericoronitis

Objective: The correlation between anatomy features of impacted mandibular third molars (M3Ms) and prevalence of pericoronitis was only interpreted using univariate analysis. This study investigated this correlation using multivariable analysis to determine the relationship between pericoronitis prevalence and the M3Ms' anatomical features. Methods: This cross-sectional study recruited 245 patients with 338 impacted M3Ms. One researcher collected participants' demographic characteristics such as sexes, age, side, and pericoronitis condition. The radiographic characteristics of M3Ms, including eruption direction and impacted levels according to Pell-Gregory classification, were assessed based on their orthopantomograms. Initially, univariate analyses were used to determine potential demographic and radiographic factors that correlated to pericoronitis. These factors were, then, analyzes using Firth's logistic regression. Results: No significant difference was found between non- and pericoronitis groups about sexes, age, side (p  > 0.05). The univariate analyses showed that proportion of vertical impacted levels and eruption direction of M3Ms were significantly different between non- and pericoronitis groups. Firth's logistic regression analysis indicated that M3Ms with impacted level A were more likely to suffer from pericoronitis than ones at level B (odds ratio (OR) = 3.34), wheraes M3Ms impacted level II had higher risk of pericorinitis than ones at level I (OR = 1.63). Vertical M3Ms were more likely to develop pericoronitis than horizontal (OR = 5.78) ones. Conclusion: M3M angulation and impacted level are significant factors relating to pericoronitis prevalence. M3Ms with vertical eruption, vertically level A, and horizontally level B are more likely to have pericoronitis.

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.

A retrospective longitudinal assessment of artificial intelligence-assisted radiographic prediction of lower third molar eruption

Prediction of lower third molar eruption is crucial for its timely extraction. Therefore, the primary aim of this study was to investigate the prediction of lower third molar eruption and its uprighting with the assistance of an artificial intelligence (AI) tool. The secondary aim was identifying the incidence of fully erupted lower third molars with hygienic cleansability. In total, 771 patients having two panoramic radiographs were recruited, where the first radiograph was acquired at 8-15 years of age (T1) and the second acquisition was between 16 and 23 years (T2). The predictive model for third molar eruption could not be obtained as few teeth reached full eruption. However, uprighting model at T2 showed that in cases with sufficient retromolar space, an initial angulation of < 32° predicted uprighting. Full eruption was observed for 13.9% of the teeth, and only 1.7% showed hygienic cleansability. The predictions model of third molar uprighting could act as a valuable aid for guiding a clinician with the decision-making process of extracting third molars which fail to erupt in an upright fashion. In addition, a low incidence of fully erupted molars with hygienic cleansability suggest that a clinician might opt for prophylactic extraction.

A Review of Evidence-Based Recommendations for Pericoronitis Management and a Systematic Review of Antibiotic Prescribing for Pericoronitis among Dentists: Inappropriate Pericoronitis Treatment Is a Critical Factor of Antibiotic Overuse in Dentistry

This work provides a narrative review covering evidence-based recommendations for pericoronitis management (Part A) and a systematic review of antibiotic prescribing for pericoronitis from January 2000 to May 2021 (Part B). Part A presents the most recent, clinically significant, and evidence-based guidance for pericoronitis diagnosis and proper treatment recommending the local therapy over antibiotic prescribing, which should be reserved for severe conditions. The systematic review includes publications analyzing sets of patients treated for pericoronitis and questionnaires that identified dentists’ therapeutic approaches to pericoronitis. Questionnaires among dentists revealed that almost 75% of them prescribed antibiotics for pericoronitis, and pericoronitis was among the top 4 in the frequency of antibiotic use within the surveyed diagnoses and situations. Studies involving patients showed that antibiotics were prescribed to more than half of the patients with pericoronitis, and pericoronitis was among the top 2 in the frequency of antibiotic use within the monitored diagnoses and situations. The most prescribed antibiotics for pericoronitis were amoxicillin and metronidazole. The systematic review results show abundant and unnecessary use of antibiotics for pericoronitis and are in strong contrast to evidence-based recommendations summarized in the narrative review. Adherence of dental professionals to the recommendations presented in this work can help rapidly reduce the duration of pericoronitis, prevent its complications, and reduce the use of antibiotics and thus reduce its impact on patients’ quality of life, healthcare costs, and antimicrobial resistance development.

Anatomical Risk Factors of Inferior Alveolar Nerve Injury Association with Surgical Extraction of Mandibular Third Molar in Korean Population

The purpose of this study was to analyze the incidence and risk factors of possible inferior alveolar nerve (IAN) injury after extraction of the mandibular third molars. A total of 6182 patients were examined for 10,310 mandibular third molar teeth. Panoramic radiography and patients’ medical records were used to analyze age, gender, and impaction pattern of the mandibular third molar. Cone beam computed tomography (CBCT) was used to investigate the detailed pathway of the inferior alveolar nerve and evaluated the presence of symptoms of nerve damage after tooth extraction. In CBCT, 6283 cases (61%) of the inferior alveolar nerve were actually in contact with the root of the mandibular third molar. The correlation with the panoramic signs of root darkening (p < 0.001), root deflection (p < 0.001), interruption of the IAN (p < 0.001), diversion of the IAN (p < 0.001), and narrowing of the IAN (p < 0.001) had statistical significance. Of the 4708 patients who underwent surgical extraction, 31 (0.658%) complained of nerve damage. Among them, 30 patients (0.637%) complained of symptoms of inferior alveolar nerve damage, and 1 patient (0.02%) complained of symptoms of lingual nerve damage. There was a significant correlation with IAN injury in cases where the roots became dark at the IAN area (p = 0.018) and there was diversion of the IAN at the root area (p = 0.041). When the narrowing of the IAN and the lingual driving pathway of the inferior alveolar nerve appeared simultaneously in CBCT, the risk of IAN injury was high.

Microbial Profile During Pericoronitis and Microbiota Shift After Treatment

The microflora of the distal pocket is considered as the major cause of pericoronitis. How the oral microflora changes during pericoronitis and whether different types of impacted third molar harbor the same microflora are still unknown. Saliva, subgingival plaque, and gingival plaque of mandibular third molars (M3Ms) were collected from twelve patients with acute pericoronitis. They were given local irrigation or local irrigation + antibiotics according to symptoms. Samples were harvested at the first visit with pericoronitis, 1 week after treatment, and 6 weeks after treatment. 16S rRNA gene polymerase chain reaction products were generated and sequenced after DNA isolation. Comparison of three sampling sites showed that, the subgingival plaque of M3Ms had most remarkable changes in symptomatic period, including a significant increase in microbial richness, and a convergent trend in microbial composition. After treatment, the subgingival microbiome was altered and largely returned to the state in asymptomatic period. In summary, the distal subgingival microbiota of M3M was most likely to be associated with the pathogenesis of pericoronitis. The post-treatment microbiota shift of M3M proved the effectiveness of treatment. The inclination type of impacted M3Ms and treatment method would also make a difference to the pericoronal microbiota.

Association between mandibular third molar position and the occurrence of pericoronitis: A systematic review and meta-analysis

OBJECTIVE

The aim of this study was to investigate the association between mandibular third molar position and occurrence of pericoronitis.

DESIGN

The systematic review was performed based on PRISMA criteria (Prospero: CRD42018102835). The electronic search was performed in Medline, Virtual Health Library and Web of Science (until August 2018), without language restriction. Two researchers independently selected studies, extracted data, and assessed methodologic quality. Twenty-one articles were included in the review, comprising 6895 patients, with 1913 third mandibular molars being affected by pericoronitis. Ten studies were incuded in meta-analysis.

RESULTS

The third molar in vertical position of Winter is the one with the greatest chance of presenting pericoronitis, compared to the other positions, while the horizontal position decreases this chance. There was no significant difference in the chance of pericoronitis between positions I and II of Pell & Gregory (OR: 0.29; IC: 0.07-1.23, I² = 88%). Third molars classified in position A had greater chance of pericoronitis when compared to those in position B (OR: 7.13; IC: 1.31-38.74, I² = 93%). The vertical position of the lower third molar is more associated with the occurrence of pericoronitis when compared to the other positions.

CONCLUSIONS

Vertical position of the lower third molar is more associated with the occurrence of pericoronitis when compared to the other Winter' positions. Considering Pell and Gregory positions, position A had a greater chance of pericoronitis compared to position B. The prophylactic removal of lower third semi-erupted vertical molar or in position A is indicated to prevent pericoronitis.

Prevalence of impacted teeth in a Brazilian subpopulation

The objective of this study was to estimate the prevalence of impacted teeth in a subpopulation of Brazilian patients based on the retrospective analysis of panoramic radiographs obtained at an oral radiology clinic. Out of 1,977 panoramic radiographs, 1,352 fulfilled inclusion criteria, and 22,984 teeth were assessed. Data were statistically analyzed using Kolmogorov-Smirnov's and Levene's tests; significance was set at 5%. The number of impacted teeth was assessed using analysis of variance and Tukey's post-hoc test. Our results showed significant differences for tooth type and patient age when analyzed separately (p < 0.05); gender did not show significant results (p > 0.05). Correlations between age and gender showed significant differences (p < 0.05), as did the correlations between age, gender and tooth type (p < 0.05). Mandibular molars were the teeth most frequently affected (p < 0.05), followed by maxillary molars (p < 0.05). Other tooth types did not present significant differences among themselves (p > 0.05). Patients aged 22 years or younger were the most frequent ones (p < 0.05). No significant differences were observed between age groups 37 and 51 years and 52+ (p > 0.05). According to the methodology here employed, gender did not affect tooth impaction, whereas age (22-36 years) and tooth type (mandibular third molars) strongly influenced results.