Association between the presence of a partially erupted mandibular third molar and the existence of caries in the distal of the second molars

Assessing current clinical eruption stage of mandibular third molars by dental panoramic radiography

OBJECTIVE

We examined whether dental panoramic radiography (PAN) can be used to identify the clinical stage of eruption of mandibular third molars at the time of radiological examination.

MATERIALS AND METHODS

Cross-sectional data included records from clinical oral examination and PANs of university students. In the retrospective analysis of 345 mandibular third molars in 189 participants (20% men, 80% women; mean age 20.7 years; standard deviation [SD] ± 0.6), clinical stages of eruption were compared with their radiographic depth in bone, inclination, and root development. Statistics included χ2, Mann-Whitney U tests, and logistic regression.

RESULTS

Significant (p < 0.001) predictor variables for assessing the clinical stage of eruption were radiographic depth in bone and inclination. All teeth radiologically at a depth of the cementoenamel (CE) junction of the neighbouring second molar or deeper were clinically unerupted. Above the CE junction, 80% of vertical and 97% of distoangular teeth were connected to the oral cavity, and 82% of mesioangular and 69% of horizontal teeth were clinically unerupted.

CONCLUSION

All teeth below or at the CE junction are clinically unerupted. Above the CE junction, stage of eruption should be assessed together with the inclination, but horizontally inclined teeth are recommended to be verified clinically.

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.

Mandibular Second Molars and Their Pathologies Related to the Position of the Mandibular Third Molar: A Radiographic Study

Objective

The aim of this study was to determine the prevalence of mandibular third molar malposition and its impact in relation to the lower second molar using panoramic radiography.

Methods and Materials

This was a cross-sectional descriptive study of 353 panoramic images of patients who visited the Dental Clinic of the International University of Rabat. Panoramic images were analyzed in order to determine the number of second molar pathologies associated with the positions of third molars. The following radiographic lesions on the second molar were recorded: caries, root resorption and distal alveolysis. The Chi-square test was used to assess the association between different variables.

Results

Of these 353 radiographies, 169 were males, ie, 48%, and 184 were females, ie, 52%. The age range was from 18 to 63 years. The prevalence of the impacted position of the lower third molar was noted in 60%. Distal caries on the second mandibular molar was present in 47.5% of instances having an impacted third molar. Caries was present in 65.5% of wisdom teeth in a normal position and was also present in 79.6% of the impacted teeth. This difference was statistically significant with p = 0.01. The angulation of the third molar is a factor of caries of the second molar: 58.56% of them were carious. Of all the teeth in association with an angulation, 72.03% showed distal alveolysis in the second molar. In addition, root resorption was found in 20.4% of second molars linked to a wisdom tooth in all angulation occurrences.

Conclusion

It has been noted that among the pathologies seen on the mandibular second molar, distal alveolysis accounts for the majority of cases (58%), followed by caries (47.5%) and root resorption (13.3%). This study illustrated the importance of performing Orthopantomogram X-rays at each new consultation in patients over the age of 18.

Microcomputed tomography analysis of the radicular residual dentin thickness in mandibular second molars after virtual fiber post placement: Identification of danger zones

STATEMENT OF PROBLEM

Mandibular second molars have variable root, pulp chamber floor, and radicular groove morphologies, potentially affecting residual dentin thickness and post placement suitability. However, an identification of the danger zones is lacking.

PURPOSE

The purpose of this in vitro study was to investigate the residual dentin thickness in the danger zone of mandibular second molars after virtual fiber post placement by using a simulation method based on microcomputed tomography (μCT).

MATERIAL AND METHODS

A total of 84 extracted mandibular second molars were scanned using μCT and classified according to root morphology (separate or fused) and pulp chamber floor morphologies (C-shaped, non-C-shaped, or no pulp chamber floor). Fused-root mandibular second molars were further classified based on the radicular groove type (V-, U-, or Ω-shaped). All specimens were accessed, instrumented, and rescanned with μCT. Two types of commercial fiber posts were also scanned. Clinical fiber post placement was simulated in all prepared canals by using a multifunctional software program. The minimum residual dentin thickness of each root canal was measured and analyzed by using nonparametric tests to identify the danger zone. Perforation rates were calculated and recorded.

RESULTS

Larger fiber posts decreased minimum residual dentin thickness (P<.05) and increased perforation rate. In regard to mandibular second molars with separate roots, the distal root canal exhibited a significantly higher minimum residual dentin thickness than the mesiobuccal and mesiolingual root canals (P<.05). However, no significant difference in minimum residual dentin thickness was found between the different canals in fused-root mandibular second molars with C-shaped pulp chamber floors (P<.05). Fused-root mandibular second molars with Ω-shaped radicular grooves had a lower minimum residual dentin thickness than those with V-shaped radicular grooves (P<.05) and demonstrated the highest perforation rate.

CONCLUSIONS

The morphologies of the root, pulp chamber floor, and radicular groove were correlated with residual dentin thickness distribution in mandibular second molars after fiber post placement. A comprehensive understanding of mandibular second molar morphology is essential for determining the suitability of post-and-core crown restorations after endodontic treatment.

Parameters associated with radiographic distal surface caries in the mandibular second molar adjacent to an impacted third molar

BACKGROUND

To determine the risk factors for the development of radiographic distal surface caries (rDSC) in patients who attend routine dental check-ups during an era of National Institute for Health Care Excellence third molar surgery guidelines.

METHODS

Radiographs taken during routine dental examinations involving 1012 patients from Manchester, UK were accessed. Clinical parameters, oral health, patient demographics, and socioeconomic factors were assessed. Risk factors were identified by multivariate logistic regression analysis.

RESULTS

The detected rate of rDSC was 63.9% and rDSC was distributed homogenously across all five socioeconomic groups (p = 0.425). Risk factors associated with rDSC (p < 0.001) were identified as partially erupted mesio-angularly impacted mandibular third molars, third molars with compromised molar to molar contact points, loss of lamina dura of ≥ 2 mm, male gender, increasing age, and a higher modified Decayed Missing Filled Tooth score.

CONCLUSION

rDSC was significantly associated with the angulation of third molars, the compromised contact position of the adjacent third molar, the periodontal status of the distal aspect of the second molar and the cumulative history of oral health in a population governed by specific third molar guidelines. An active approach to third molar surgical management could reduce rDSC and serve this population, irrespective of patients' socioeconomic or deprivation status.

Influence of inflammation on bleeding and wound healing following surgical extraction of impacted lower third molars

OBJECTIVE

This study aimed to investigate the effect of inflammatory states following impacted lower third molar (ILTM) surgery regarding postoperative bleeding and wound healing.

METHODS

The study included patients who underwent extraction of ILTMs associated with or without inflammatory conditions. Post-extraction bleeding and wound healing were assessed. In addition, mean grey values (MGVs) of alveolar bone and bone height using an orthopantomography radiograph were analyzed.

RESULTS

A total of 376 patients were enrolled; 171 pericoronitis, 51 pulpitis, 44 chronic periapical periodontitis, 36 chronic periodontitis, and 74 control. The bleeding score in the control group was significantly lower than in the periapical periodontitis and periodontitis groups. Excellent wound healing for control, pericoronitis, pulpitis, periapical periodontitis, and periodontitis groups was (78.38%, 35.67%, 70.59%, 70.45%, and 33.33%, respectively). Patients with pericoronitis and periodontitis had significantly poorer wound healing (P < 0.01). The MGV in periapical periodontitis and periodontitis was considerably lower than in the control group.

CONCLUSIONS

The inflammatory conditions associated with ILTMs increase the risk of bleeding. So suturing with the placement of local hemostatic agents over a pressure pack alone is recommended. The poorest wound healing was in localized gingival inflammation. Furthermore, MGV was affected by age and was lower with periapical periodontitis.

Historical aspects about third molar removal versus retention and distal surface caries in the second mandibular molar adjacent to impacted third molars

This paper provides an insight into the historical recommendations regarding removal of mandibular third molars, as set out by the Royal College of Surgeons of England and the National Institutes of Health in the USA, as well as regional guidance from the National Institute for Health and Care Excellence and the controversy that surrounds surgical removal of third molars. The influences of third molar management as it developed in the UK, the historical economic evaluations, and the available evidence base on third-molar removal versus retention are described. This article seeks to address the growing concerns regarding the increasing frequency of distal surface caries (DSC) in mandibular second molar teeth when the decay is associated with asymptomatic, partially erupted, mandibular third molars, especially when they are mesially or horizontally impacted. Lastly, we illustrate radiographs of patients affected by DSC and how guidance that has been issued by a guideline institution regarding third molar surgery, even though it is based on insufficient evidence, is perceived as a strictly compulsory clinical strategy, and has been used in clinical practice in the UK for more than 20 years.

Pathologies Associated with Second Mandibular Molar Due to Various Types of Impacted Third Molar: A Comparative Clinical Study

Introduction

Impacted third molars are associated with various degrees of damage to the second molars. The possible complications also include distal cervical caries, root resorption of second molar, periodontal problems, odontogenic cysts, etc. Whether a particular impacted third molar is going to affect second molar depends upon its position and orientation in the bone.

Materials and Method

This study was carried out in 418 cases. Three examiners evaluated the patient clinically and radiographically and only those cases were included in this study where at least two observers agreed. A total of 341 cases (163 males and 178 female), age range (15-40 years) with impacted mandibular third molars, were included. Clinically and radiographically, the impacted mandibular third and second molars were evaluated; simultaneously, the prevalence of various pathologies associated with mandibular second molar (dental caries, periodontal pockets, root resorption) due to impacted third molar was also evaluated and compared among various types and positions of impactions.

Results

Statistical analysis was carried out using Pearson Chi-square and Asymp. Sig. (two-sided) test. Prevalence of mesioangular impactions was maximum (50.1%). Mesioangular impaction and position B (Pell and Gregory classification) were significantly associated with dental caries (32.20% and 33.90%, respectively), and periodontal pockets were seen higher with position B impactions (26.8%) {horizontal (14.7%), disto-angular (12.10%), vertical (14.5%) mesioangular (16.4%%)} in adjacent mandibular second molar. Root resorption was seen maximally in horizontal impaction (17.30%) with position c type (12.30%). The order of pathologies associated with second molar due to impacted third molar was dental caries (19.9%) > periodontal pockets (15.2%) > root resorption (8.5%).

Discussion

Evidence regarding pathologies are associated with second molar due to impacted third molar aids in decision making for surgical removal of third molars. Different types of impaction and the prevalence of pathologies related to them would aid in treatment planning of the impacted tooth as certain types have high probability of pathologies associated.

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.

Anatomical Positions of Mesially/Horizontally Impacted Mandibular Third Molars are Significant Predictors for Distal Caries in Adjacent Second Molars

Background

Prevalence of distal caries in mandibular second molars (M2Ms) and its relationship with impacted condition of the adjacent mandibular third molars (M3Ms) have been reported in some studies. The results, however, were ambiguous because of including all impaction types and using univariate analysis for statistics.

Aim

This study aimed to determine anatomical features of mesially/horizontally impacted mandibular third molars (M3Ms) that could predict distal caries in the adjacent mandibular second molars (M2Ms) using multivariable analysis.

Materials and Methods

The study sample consisted of 300 digital panoramic radiographs of patients who underwent impacted M3Ms extraction. Two independent researchers collected the following variables from 446 pairs of M2M-M3M: sex, age, status of distal caries in M2Ms, mesial angulation, and Pell–Gregory classification of M3Ms.

Results

The prevalence of distal caries was 50.67%. Multivariable Firth's logistic regression analysis showed that age (β = 0.066, 95% CI = 0.023–0.113), mesial angulation (<30°: β = −1.205, 95% CI = −1.955 to −0.499; >70°: β = −0.730, 95% CI = −1.184 to −0.282), vertical position (level B: β = 2.275; 95% CI = 0.015–7.175; level A: β = 3.008; 95% CI = 0.755–7.905), and horizontal position (level II: β = 1.515; 95% CI = 0.444–2.874; level I: β = 1.423; 95% CI = 0.283–2.825) were significant variables after adjusting for sex in the final model for predicting distal caries (p < 0.05).

Conclusions

In conclusion, anatomical positions of impacted M3Ms, such as mesial angulation and Pell–Gregory classification were significant predictors of distal caries in M2Ms.

Machine learning to predict distal caries in mandibular second molars associated with impacted third molars

Impacted mandibular third molars (M3M) are associated with the occurrence of distal caries on the adjacent mandibular second molars (DCM2M). In this study, we aimed to develop and validate five machine learning (ML) models designed to predict the occurrence of DCM2Ms due to the proximity with M3Ms and determine the relative importance of predictive variables for DCM2Ms that are important for clinical decision making. A total of 2642 mandibular second molars adjacent to M3Ms were analyzed and DCM2Ms were identified in 322 cases (12.2%). The models were trained using logistic regression, random forest, support vector machine, artificial neural network, and extreme gradient boosting ML methods and were subsequently validated using testing datasets. The performance of the ML models was significantly superior to that of single predictors. The area under the receiver operating characteristic curve of the machine learning models ranged from 0.88 to 0.89. Six features (sex, age, contact point at the cementoenamel junction, angulation of M3Ms, Winter's classification, and Pell and Gregory classification) were identified as relevant predictors. These prediction models could be used to detect patients at a high risk of developing DCM2M and ultimately contribute to caries prevention and treatment decision-making for impacted M3Ms.

Analysis of Factors Related to Distal Proximal Caries on the Distal Surface of the Mandibular Second Molar Induced by an Impacted Mandibular Third Molar

Objective

To analyze the factors related to distal proximal caries of the mandibular second molar (MSM) induced by an impacted mandibular third molar (MTM).

Methods

A total 500 panoramic radiographs of patients with impacted MTMs who were treated in the Department of Stomatology of the Affiliated Hospital of Yanbian University between October 2017 and October 2019 were selected. Descriptive and bivariate analyses were conducted, and the diagnosis of caries in the MSM and the position of the MTM were evaluated.

Results

The posterior margin space of the MSM was larger in males (13.5 mm) than females (11.1 mm, P < 0.001) and correlated with the MTM’s impacted depth and eruption degree (P < 0.001). The prevalence of distal proximal caries of the MSM was 37.6%, and a χ² test showed that age, impacted depth, impacted direction, impacted angle, degree of occurrence, and CEJ distance were correlated with caries in the distal adjacent surface of the MSM (P < 0.001). Logistic multivariate analysis showed that the impacted depth was at position A or B, the impacted direction was mesioangular, and the impacted angle was <80°. Distal adjacent caries of MSMs were prone to occur when entirely or partially emergent. CEJ distance was not an independent factor for caries. The severity of caries in an MSM’s distal adjacent surface had statistical significance on the impacted depth and impacted angle (P < 0.001).

Conclusion

The posterior margin space of the MSM influences the impacted condition of the MTM. Preventive extraction can be considered if the impacted angle is <80°, especially in the case of a fully or partially emergent MTM at position A or B and mesioangular impacted areas.

Infrared Thermography in the Evaluation of Dental Socket Healing After Photobiomodulation Therapy: A Case Report

Introduction: The aim of this article was to evaluate the efficacy of photobiomodulation therapy (PBMT) in the alveolar tissue healing process post-extraction using infrared thermography (IT). Case Presentation: A 36-year-old male patient had teeth extractions (18 and 28). Four PBMT sessions (660 nm; 2 J per tooth) were performed in the region of tooth 28 and recorded with thermographic images to compare the healing process, bilaterally. In the first two postoperative sessions, the temperature was higher (hyperradiant) on the left side (treated). After the third laser application, the left side was hyporradiant. In later session, the treated side became hyperradiant compared to the control side. The alveolus of tooth 28 showed more rapid healing than tooth 18 over a period of 60 days. Conclusion: IT can be used to detect the favorable effect of PBMT on accelerating the healing process in the alveolus within 60 days after the tooth extraction.

Radiographic Position of Impacted Mandibular Third Molars and Their Association with Pathological Conditions

Objectives

This study aimed to assess the radiographic position of impacted mandibular third molars (IMTMs) and their association with pathological conditions.

Materials and Methods

The impaction depth, relationship with ramus, and angulation of 1600 IMTMs and their association with 2^nd molar distal caries and root resorption, pathological conditions, and proximity to the mandibular canal were evaluated on panoramic radiographs. The IMTM position was determined based on the depth of impaction according to the Pell and Gregory classification, relationship with ramus according to the Pell and Gregory classification, and angulation according to the Winter's classification. The classical and Bayesian logistic regressions were applied to analyze the effect of IMTM position on the associated complications using the odds ratio (OR) and 95% confidence interval (credible interval for Bayesian models). Two-tailed P value < 0.05 was considered statistically significant.

Results

Of 1600 IMTMs evaluated in this study, 195 (12.2%), 252 (15.8%), and 119 (7.4%) had caused second molar distal caries, second molar root resorption, and pathological lesions, respectively, and 872 (54.5%) had contact with the mandibular canal. Impaction angulation was a risk factor for second molar distal caries (maximum OR = 5.01, 95% CI: 3.12-8.18). Changed angulation and greater impaction depth were the risk factors for second molar root resorption (minimum OR = 1.64, 95% CI: 0.58-4.02). Decreased distance between the ramus and distal side of the second molar was a risk factor for associated pathological lesions (minimum OR = 2.73, 95% CI: 1.79-4.25). Mesioangular and horizontal angulations and greater impaction depth were the risk factors for contact with the mandibular canal (maximum OR = 3.44, 95% CI: 2.6-4.57 and minimum OR = 1.3, 95% CI: 094-1.8).

Conclusions

The frequency of complications associated with IMTMs was low, but considerable. The occurrence of these conditions might be affected by the impaction position. Thus, regular follow-ups are recommended in order to be able to surgically intervene when the first signs of pathologies arise.

Radiographic pathologies associated with third molar teeth in Polish population: A retrospective study

Introduction: There is a plethora of pathologies that might be associated with the presence of third molar teeth (M3s). In the following study, the impact of M3s status on the occurrence of radiographic lesions of adjacent second molars (M2s) was evaluated. Materials/Methods: A total of 1,988 panoramic radiographs were included in the statistical analysis. M3s were categorized as non-impacted (N-M3s) or impacted (I-M3s). I-M3s were subsequently divided into partially or completely impacted. Radiographic lesions in the second molars area, such as caries, external root resorption (ERR), and alveolar bone loss (ABL) were assessed. For the purpose of statistical analysis, the level of significance was set at 0.05. Results: Among all evaluated panoramic radiographs, 1,621 (81.13%) showed at least one N-M3, 535 (26.78%) at least one partially I-M3, and 344 (17.2%) at least one completely I-M3. In the presence of M3s, the frequency of caries, ERR and ABL was determined at 17.98%, 0.68% and 23.96%, respectively, with the odds ratio (OR) for the occurrence of the above-mentioned pathologies at the level of 1.23, 6.97 and 1.31. Notably, the presence of N-M3s particularly increased the odds of caries, while I-M3s significantly increased the odds of ERR and ABR (ORs = 1.42; 26.0; 2.36, respectively). Conclusions: The presence of M3s, irrespective of their impacted or non-impacted status, increases the risk of pathologies in M2s. Therefore, prophylactic extraction of M3s or active surveillance of patients could be recommended.

Management of Impacted Third Molars

Impacted third molars occur in a significant number of patients and often require treatment because of presence of symptoms and/or disease. Management of these teeth typically involves referral to oral and maxillofacial surgeons for diagnosis, treatment planning, and ultimate removal if indicated. Proper diagnosis and treatment planning helps optimize surgical results at each stage of the procedure, and ultimately patient outcomes. Adherence to proper surgical techniques helps minimize risks and complications associated with the procedure. Multiple alternative surgical techniques also exist for uncommon, but potentially complicated, situations that arise with some impacted third molars.

The Retromolar Space and Wisdom Teeth in Humans: Reasons for Surgical Tooth Extraction

OBJECTIVE

 This article explores the problem of developing pathologies in the retromolar region. Findings can serve a framework for disease prevention and for the improvement of the quality of life of patients. The present study aims to justify the possibility of utilizing morphometric methods to foresee problems in the eruption of third molars.

MATERIALS AND METHODS

 A comprehensive morphometric study of the lower jaw and facial skeleton involves 100 skulls of Homo sapiens to identify the anatomical causes of problems with wisdom teeth eruption. All said skulls are divided in two groups: I: skulls with intact dentition; II: skulls with impacted third molars.

RESULTS

 This work allows detecting abnormalities in the eruption of the third molar with high probability of success. The abnormalities in point are considered not only those associated with the generally accepted parameters but also those that occur in the leptoprosopic face cases.

CONCLUSIONS

 Face type and the structural features of the facial skeleton play a significant role in the abnormal eruption of the lower third molar.

The ability of orthodontists and maxillofacial surgeons in predicting spontaneous eruption of mandibular third molar using panoramic serial radiographs

OBJECTIVE

To evaluate the skill of orthodontists and oral/maxillofacial surgeons (OMFS) in providing a prognosis of mandibular third molars spontaneously erupted, through follow-up panoramic analysis.

METHODS

22 orthodontic patients treated without extraction, presenting spontaneously erupted mandibular third molars (n = 44) were analyzed through panoramic serial radiographs. The first panoramic radiograph was obtained just after orthodontic treatment (PR1), in patients aging from 13 to 19 years. A second panoramic radiograph (PR2), was obtained in average two years later. The radiographs were randomly analyzed by 54 specialists, 27 orthodontists and 27 OMFS, to obtain the opinion about the approach to be adopted to these teeth in PR1. Then, another opinion was collected by adding a serial radiograph (PR1+2).

RESULTS

The concordance of the answers was moderate for OMFS (Kappa 0.44; p< 0.0001) and significant for orthodontists (Kappa 0.39; p< 0.0001). In the analysis of the first radiograph (PR1) of the spontaneously erupted molars, OMFS indicated extraction in 44.5% of cases, while orthodontists indicated in 42%, with no difference between groups (p= 0.22). In PR1+2 analysis, orthodontists maintained the same level of extraction indication (45.6%, p= 0.08), while surgeons indicated more extractions (63.2%, p< 0.0001).

CONCLUSIONS

Orthodontists and OMFS were not able to predict the eruption of the third molars that have erupted spontaneously. Both indicated extractions around half of the third molars. A follow-up analysis, including one more radiograph, did not improve the accuracy of prognosis among orthodontists and worsened for OMFS.

A systematic review of second molar distal surface caries incidence in the context of third molar absence and emergence

Objective The aim of this systematic review was to gain a greater insight into the incidence rates of distal surface caries (DSC) on second permanent molars.Data sources A literature search using the Cochrane Library, Lilacs, Embase and Medline via Ovid retrieved English and non-English language articles from inception to June 2016. The electronic searches were supplemented with reference searching and citation tracking. Reviewers independently and in duplicate performed data extraction and completed structured quality assessments using a validated risk of bias tool for observational studies and categorised the summary scores.Data selection The search yielded 81 records and, after application of inclusion and exclusion criteria, two incidence studies were included in this systematic review.Data extraction The DSC incidence was reported in one study as relative risk (RR = 2.53; 95% CI, 1.55 to 4.14) adjacent to erupted, (RR = 0.83; 95% CI, 0.11 to 6.04) soft tissue impacted and (RR = 1.44; 95% CI, 0.55 to 3.72) bony impacted third molars in comparison to when the third molar was absent with a 25-year follow-up. The second study reported a DSC incidence of 100 surface-years (1% of all sites) with an 18-month follow-up period.Conclusions Both cohort studies indicated that DSC incidence was higher when third molars were erupted in the intermediate term, but greater over the long term for an ageing male population. However, further high-quality research is required to improve the accuracy of these findings.

Prophylactic removal of impacted mandibular third molars: a systematic review and economic evaluation

BACKGROUND

Impacted third molars are third molars that are blocked, by soft tissue or bone, from fully erupting through the gum. This can cause pain and disease. The treatment options for people with impacted third molars are removal or retention with standard care. If there are pathological changes, the current National Institute for Health and Care Excellence guidance states that the impacted third molar should be removed.

OBJECTIVE

The objective of this study was to appraise the clinical effectiveness and cost-effectiveness of the prophylactic removal of impacted mandibular third molars compared with retention of, and standard care for, impacted third molars.

METHODS

Five electronic databases were searched (1999 to 29 April 2016) to identify relevant evidence [The Cochrane Library (searched 4 April 2016 and 29 April 2016), MEDLINE (searched 4 April 2016 and 29 April 2016), EMBASE (searched 4 April 2016 and 29 April 2016), EconLit (searched 4 April 2016 and 29 April 2016) and NHS Economic Evaluation Database (searched 4 April 2016)]. Studies that compared the prophylactic removal of impacted mandibular third molars with retention and standard care or studies that assessed the outcomes from either approach were included. The clinical outcomes considered were pathology associated with retention, post-operative complications following extraction and adverse effects of treatment. Cost-effectiveness outcomes included UK costs and health-related quality-of-life measures. In addition, the assessment group constructed a de novo economic model to compare the cost-effectiveness of a prophylactic removal strategy with that of retention and standard care.

RESULTS

The clinical review identified four cohort studies and nine systematic reviews. In the two studies that reported on surgical complications, no serious complications were reported. Pathological changes due to retention of asymptomatic impacted mandibular third molars were reported by three studies. In these studies, the extraction rate for retained impacted mandibular third molars varied from 5.5% to 31.4%; this variation can be explained by the differing follow-up periods (i.e. 1 and 5 years). The findings from this review are consistent with the findings from previous systematic reviews. Two published cost-effectiveness studies were identified. The authors of both studies concluded that, to their knowledge, there is currently no economic evidence to support the prophylactic removal of impacted mandibular third molars. The results generated by the assessment group's lifetime economic model indicated that the incremental cost-effectiveness ratio per quality-adjusted life-year gained for the comparison of a prophylactic removal strategy with a retention and standard care strategy is £11,741 for people aged 20 years with asymptomatic impacted mandibular third molars. The incremental cost per person associated with prophylactic extraction is £55.71, with an incremental quality-adjusted life-year gain of 0.005 per person. The base-case incremental cost-effectiveness ratio per quality-adjusted life-year gained was found to be robust when a range of sensitivity and scenario analyses were carried out.

LIMITATIONS

Limitations of the study included that no head-to-head trials comparing the effectiveness of prophylactic removal of impacted mandibular third molars with retention and standard care were identified with the assessment group model that was built on observational data. Utility data on impacted mandibular third molars and their symptoms are lacking.

CONCLUSIONS

The evidence comparing the prophylactic removal of impacted mandibular third molars with retention and standard care is very limited. However, the results from an exploratory assessment group model, which uses available evidence on symptom development and extraction rates of retained impacted mandibular third molars, suggest that prophylactic removal may be the more cost-effective strategy.

FUTURE WORK

Effectiveness evidence is lacking. Head-to-head trials comparing the prophylactic removal of trouble-free impacted mandibular third molars with retention and watchful waiting are required. If this is not possible, routine clinical data, using common definitions and outcome reporting methods, should be collected.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016037776.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 30. See the NIHR Journals Library website for further project information.

Effect of antiseptic gels in the microbiologic colonization of the suture threads after oral surgery

Three different bioadhesive gels were evaluated in a double-blind randomized clinical trial in which microbial growth in the suture thread was assessed following post-surgical application of the aforementioned gels. Also assessed in this trial were, the intensity of post-surgical pain as well as the degree of healing of the patients’ surgical wounds. A total of 21 patients (with 42 wisdom teeth) participated in this trial. Chlorhexidine gel, chlorhexidine-chitosan gel, and hyaluronic acid gel were evaluated, with a neutral water-based gel serving as the control agent. The aerobic and facultative anaerobic bacterial recovery on blood agar was lower in the placebo group than in the experimental groups. The most significant difference (p = 0.04) was observed in the chlorhexidine-chitosan group. in which the growth of Blood Agar and Mitis Salivarius Agar was significantly higher than in the placebo group. The intensity of post-surgical pain was very similar among all the groups. Significantly better healing rates were observed in the patients treated with chlorhexidine-chitosan gel when compared with those who used the placebo gel (p = 0.03), and in particular when compared with those patients who used hyaluronic acid gel (p = 0.01). Through our microbiological analyses, we were able to conclude that none of the bioadhesive gels tested resulted in beneficial reductions in the bacterial/fungal populations. However, the healing rates of patients who were treated with chlorhexidine-chitosan were better than those of the patients who used either the placebo gel or the hyaluronic acid gel.

Prophylactic extraction of non-impacted third molars: is it necessary?

BACKGROUND

The decision of removing a non-impacted 3rd molar, unlike extraction of an impacted 3rd molar, is challenging for dentists as well as patients. This study investigates the pathologies affecting second molars situated adjacent to asymptomatic non-impacted 3rd molars.

METHODS

This retrospective study included digital radiographs of 749 patients taken between April to October 2015. Panoramic radiographs were evaluated for the presence of erupted asymptomatic non-impacted 3rd molars and pathologies on adjacent second molars. The patients were reviewed according to age and gender.

RESULTS

A total of 2342 asymptomatic 3rd molars were assessed in the study based on the inclusion and exclusion criteria, and 2112 of them were found to be non-impacted. The second molars adjacent to non-impacted 3rd molars were shown to be significantly associated with distal caries (25.2%), mesial bone loss (10.5%) and total bone loss (37.2%), i.e., mesial as well as distal bone loss.

CONCLUSIONS

Pathologies of the 3rd molars and teeth adjacent to 3rd molars can occur as a result of multiple factors. Caries and periodontal disease may also occur due to the inaccessibility to maintain oral hygiene. With a regular follow-up schedule, reinforced by the dentist and good oral hygiene, several pathologies that are significantly associated with non-impacted 3rd molars can be prevented and may not require prophylactic extraction.

Influence of ozonized water on pain, oedema, and trismus during impacted third molar surgery: a randomized, triple blind clinical trial

BACKGROUND

This study aimed to evaluate the efficacy of ozonized water on pain, oedema and trismus after impacted third molar mandibular surgeries when compared to double distilled water. A randomized triple blind trial was conducted.

METHODS

Patients with third molars class II-B of Pell-Gregory were included, and surgical extraction was performed. Irrigation was done with ozonized (group 1) or double distilled water (group 2). The type of irrigation and the side to be operated were randomized. Neither the patients nor the operator or evaluator were aware of the irrigation solution. Pain, oedema and trismus were evaluated at baseline, 24-h, 48-h, 72-h and 7-days after treatment. The data were evaluated by Friedman, Wilcoxon, Mann-Whitney tests, and size effect.

RESULTS

It was included 8 men and 12 women, with a mean age of 20.9y.o. The initial pain mean was 7.94 (±12.81) (group 1) and 5.50 (±9.12) (group 2) (p > 0,05). There was a statistically significant reduction of pain, oedema and trismus in intragroup analysis (p < 0.05). There was no statistically significant difference (p > 0.05) when comparing the oedema and trismus between groups. The size effect ranged from small (0.23) to large (1.29).

CONCLUSIONS

It was concluded that ozonized water was compatible as irrigation method, not inferior to double distilled water, and had satisfactory effects on management of pain, oedema and trismus after surgical removal of the third molar.

TRIAL REGISTRATION

This clinical trial was registered in ClinicalTrials.gov NCT03501225 on April 18, 2018.

Three-dimensional position of mandibular third molars and its association with distal caries in mandibular second molars: a cone beam computed tomographic study

OBJECTIVE

To analyze the prevalence of distal caries in mandibular second molars (M2Ms) and its correlation with the three-dimensional position of mandibular third molars (M3Ms) by cone beam computed tomography (CBCT) images.

MATERIALS AND METHODS

CBCT scans involving 421 M3Ms were assessed. The presence of distal caries of M2Ms, patient age and gender, impaction depths and mesial angulation of M3Ms, the cementoenamel junction (CEJ) distances and contact point localization, and the horizontal positions of M3Ms were assessed. Risk factors were identified by multivariate logistic regression analysis.

RESULTS

The overall prevalence of distal caries in M2Ms was 31.6%. Mesial angulation (16°-75°) of M3Ms, contact point localization at or below the CEJ of M2Ms, and a buccal or lingual position of M3Ms relative to the molar line were identified as risk factors for the prevalence of distal caries in M2Ms (p < 0.05). Distal caries was more severe when the mesial angulation of M3Ms was 16°-75° (p < 0.05).

CONCLUSIONS

Buccal or lingual position of M3Ms may represent a new risk factor for the distal caries in M2Ms. Mesial angulation (16°-75°) of M3Ms is a predictive parameter for both the presence and severity of distal caries in M2Ms.

CLINICAL RELEVANCE

As the presence of distal caries in M2Ms is significantly associated with the three-dimensional position of M3Ms, watchful monitoring or prophylactic removal of M3Ms should be deliberated when M3Ms are mesially angulated (16°-75°), buccally or lingually positioned, and with the contact point localization at or below the CEJ of M2Ms.

Evaluation Distal Caries of the Second Molars in the Presence of Third Molars among Saudi Patients

Objectives:

To evaluate the prevalence of distal caries in second permanent molars in the presence of third molar among patients attending university dental clinics in Riyadh City, Kingdom of Saudi Arabia.

Materials and Methods:

Clinical and radiographic data (orthopantomographs and right and left bite wings) from 313 patients attending Riyadh Elm University dental clinics, department of oral diagnosis were collected and analyzed for the presence of third molars and caries on the distal surface of the second molar. Descriptive statistics of frequency distribution, mean and standard deviation, and binary logistic regression analysis were applied to assess the association between distal surface caries on second molars and impaction status of the teeth.

Results:

The mean decayed, missing, and filled teeth score of the study participants was found to be very high, that is, 23. The prevalence of caries affecting the distal aspect of the second molar was 48.6% (n = 609) in the population. The prevalence of distal caries was significantly high in patients with fully erupted wisdom teeth followed by vertical, horizontal, and mesial impacted third molars (P < 0.05). Wisdom teeth with mesioangular, vertical, and horizontal impactions showed significant association with distal caries of second molars below the contact point, whereas, fully erupted and vertically impacted wisdom teeth showed significant association with distal surface caries of second molars above contact point. Similarly, vertically impacted wisdom teeth were found to have significant association with caries of distal surface of second molars on noncontact areas (P < 0.05).

Conclusion:

This study showed that the distal surface of the second molars is at risk of caries in the presence of third molars. However, this risk depends on eruption status, type of angulation, and contact between third and second molars. All the preventive measures should be taken to avoid caries on distal surface of second molar.

The extraction of first, second or third permanent molar teeth and its effect on the dentofacial complex

The extraction of permanent molar teeth was first introduced in 1976 as a substitution for premolar extraction in cases with mild crowding. Since then, a number of studies have investigated the effect of permanent molar extraction on dentofacial harmony. Undertaking the procedure of molar extraction is most commonly recommended in response to factors such as: gross caries, large restorations and root-filled teeth, along with its application in the management of anterior open bite and reduction in crowding in facial regions. It has been indicated, however, that before undertaking the extraction of molar teeth it is important to investigate the potential influence of the procedure on other molars, with particular consideration of their eruption path. This is due to the doubt as to the effect of the exact molar teeth extraction and their consequences. In light of this, This review was undertaken to investigate and compare the effect of first, second and the third molar teeth extraction and their subsequent dentofacial complex changes.

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 distal surface caries in the second molar among referrals for assessment of third molars: a systematic review and meta-analysis

We conducted a systematic review of epidemiological studies to assess the prevalence of distal surface caries (DSC) in second molars adjacent to third molars. We searched the Cochrane Library, Lilacs, Embase, and Medline through Ovid^® (Wolters Kluwer) to retrieve English and non-English papers from inception to June 2016, and supplemented this with a search of the references and by tracking citations. Three reviewers contributed: one reviewed all the papers, and the other two divided the rest between them. They extracted data, completed structured quality assessments with a validated risk of bias tool for observational studies, and categorised the summary scores. The search yielded 81 records and 11 studies were analysed. The considerable methodological diversity meant that five were not eligible for inclusion in the quantitative synthesis. A meta-analysis of six studies on the prevalence of DSC and a subgroup analysis of three on various third-molar angulations were indicated. The overall pooled prevalence estimate calculated with a random-effects model was 23% (95% CI 2% to 44%) among patients. Prevalence subtotals were 20% (95% CI 5% to 36%) for prospective, and 15% (95% CI 5% to 36%) for retrospective studies among teeth. A subgroup analysis of three studies with 1296 patients (1666 molars) yielded a prevalence of DSC of 36% (95% CI 5% to 67%) for mesial impactions and 22% (95% CI 1% to 42%) for horizontal impactions. DSC was present in 3% of distally-inclined impactions, (95% CI 1% to 5%) and in 7% (95% CI 1% to 13%) of vertical third molars. The studies varied. The risk of bias was low in one and moderate in two. European studies suggested that DSC may be present in about one in four referrals for the assessment of third molars, and that the risk is considerably higher in those with convergent third molar impactions.

The Effectiveness of the Cold Therapy (cryotherapy) in the Management of Inflammatory Parameters after Removal of Mandibular Third Molars: A Meta-Analysis

Introduction  Cold therapy (cryotherapy) is a common procedure recommended by dental surgeons after surgical removal of third molars, which is an invasive intervention that often deals with an expressive inflammatory response.

Objective  To investigate whether cryotherapy interferes with clinical outcomes such as pain, edema, and trismus in the postoperative period of mandibular third molar surgeries.

Data Synthesis  An electronic search was conducted in the OVID, PubMed, VHL, Science Direct, Cochrane Library, and Web of Science databases, through March 2018. The eligibility criteria included clinical trials that evaluated the effect of cryotherapy in at least one of the following variables: pain, swelling, and trismus.

Two independent reviewers assessed the studies. The methodological quality of each article was analyzed. The search strategy resulted in 1,088 articles. Following the selection process, 11 studies were included in the systematic review and 4 of them in the meta-analysis. High risk of bias was found in most of the studies according to the Cochrane Handbook assessment. Patients receiving cryotherapy had less edema than patients in the control group at second day follow-up (mean difference [MD]: -0.94; 95%CI [-1.49; -0.39]). There were no statistically significant results when comparing trismus between experimental and control group (MD: 0.43; 95%CI [-0.34;1.20]). There were insufficient available data to support influences in postoperative pain.

Conclusions  Cryotherapy applied on the first day after mandibular third molar removal can manage edema in the patients. Well-designed randomized clinical trials to test the efficacy of cryotherapy after surgical removal of third molars are needed to justify its indication.

Marginal bone loss and resorption of second molars related to maxillary third molars in panoramic images compared with CBCT

OBJECTIVES

Compare findings among observers in panoramic images (PAN) and cone beam CT (CBCT); and assess findings in PAN as indicators for marginal bone loss and resorption observed in CBCT.

METHODS

120 impacted maxillary third molars with PAN and CBCT were included. Four observers assessed morphological features: (1) tooth angulation; (2) number of roots; (3) bony impaction (yes/no) and pathology; (4) marginal bone level at the second molar (normal/>3 mm = bone loss); (5) resorption in the second molar (no/superficial/< half way through the dentin/≥ half way through the dentin/involving the pulp); (6) size of follicular space (normal/> 4 mm(cyst)). Percentage accordance and κ statistics described observer variation in PAN and CBCT. Logistic regression analyses tested findings in PAN as indicators for marginal bone loss or resorption observed in CBCT.

RESULTS

κ values were fair and interobserver accordance was marginally higher in CBCT than PAN. Agreement between PAN and CBCT was 81-88% for marginal bone loss and 68-81% for resorption. Severe resorption was more often observed in CBCT. Mesio-angulated third molars and marginal bone loss interpreted in PAN significantly indicated marginal bone loss observed in CBCT (odds ration 17-34; p < 0.012; 8.8-52.8; p < 0.02). In contrast, findings in PAN were not significant indicators for resorption observed in CBCT (p > 0.05).

CONCLUSION

In general, there was a fair agreement for marginal bone loss between PAN and CBCT, and PAN could significantly predict bone loss observed in CBCT. However, presence of resorption observed in CBCT could not be determined from PAN, and more severe resorption was observed in CBCT. CBCT is indicated if resorption in the second molar needs to be assessed.

Relationship Between Third Mandibular Molar Angulation and Distal Cervical Caries in the Second Molar

Third lower molar partially erupted is commonly encountered in dental practice. This situation challenges clinicians with the dilemma whether to remove or to monitor it, because this molar can cause pathology of the adjacent second molar. The aim of this retrospective study is to evaluate the relationship between third mandibular molar and distal cervical caries in second molar. This retrospective study analyzed 55 digital orthopantograms of adult patients and a total number of 95 mandibular third molars were assessed for eruption status, angulation, radiographic evidence of caries or restoration in the mandibular third molar, and radiographic evidence of caries or restoration in the distal surface of the mandibular second molar. The distal cervical caries in second molar is associated with fully erupted and partially erupted wisdom molar in horizontal, mesioangular and vertical position and less with presence of caries in third molar. There are caries lesions in distal second molars in mesioangular position when adjacent third molar is caries free.

What Are the Risk Factors for External Root Resorption of Second Molars Associated With Impacted Third Molars? A Cone-Beam Computed Tomography Study

PURPOSE

In relation to an impacted third molar, which is the most frequently impacted tooth, external root resorption (ERR) or dental caries can be seen on the distal surface of the adjacent second molar. The purpose of this study was to investigate the risk factors for ERR in second molars associated with impacted third molars using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

In this cross-sectional study, the presence of ERR on the adjacent second molar was investigated retrospectively on sagittal and axial CBCT slices of patients who underwent CBCT examination for diagnostic reasons (surgical removal of third molars, orthodontic assessments, and so on) between 2013 and 2017 at the Necmettin Erbakan University Faculty of Dentistry, Konya, Turkey. The primary outcome variable was ERR (yes or no). Predictor variables included demographic (age and gender) and radiographic (impacted tooth angulation and tooth type) parameters. Given that there are multiple observations per patient (1 to 4 impacted teeth), 1 third molar per patient was selected at random for study inclusion. Statistical analysis was performed using descriptive statistics, the Mann-Whitney U test, and the Pearson χ² test. Logistic regression analysis was used to determine the risk factors for ERR in second molars. The Cohen κ test was used to test intraobserver agreement. The significance level was set at P < .05.

RESULTS

Two hundred patients were analyzed, and of the 200 impacted third molars evaluated, 42 (21%) showed ERR. The severity of resorption increased with aging (P < .05). Logistic regression analysis indicated that tooth type and inclination of the third molars could predict the occurrence of ERR associated with an impacted third molar (P < .05).

CONCLUSIONS

Mesioangular and horizontal inclinations and impacted mandibular third molars posed a greater risk of ERR lesions in adjacent second molars than other inclinations (distoangular and vertical) and maxillary third molars.

Third Molar and Their Relationship with Caries on the Distal Surface of Second Molar: A Meta-analysis

PURPOSE

The aim of this meta-analysis was to determine which characteristics of mandibular third molars (MTMs) are more often associated with an increase in the prevalence/incidence of caries on the distal surface of mandibular second molars (MSMs).

METHODS

Three electronic databases were analyzed: PubMed; OVID and the Virtual Health Library. Observational studies were included, and the risk of bias was assessed using The Newcastle-Ottawa Scale. The Comprehensive Meta-Analysis software program was used for meta-analysis.

RESULTS

Fifteen studies were included in this systematic review, and five were included in the meta-analysis. The distal surface of MSMs were more likely to exhibit caries in the following scenarios: when MTMs were found in the A position, rather than the C position (OR: 3.45, 95% CI: 2.28-5.22, p<0.001); when the horizontal position was compared with the vertical (OR: 8.12, 95% CI: 3.75-17.58, p<0.001) and distoangular (OR: 9.75, 95% CI: 3.49 - 27.25, p<0.001) positions; and when the mesioangular position was compared with the vertical (OR: 7.25, 95% CI: 3.48-15.10, p<0.001) and distoangular (OR: 9.54, 95% CI: 3.47 - 26.21, p<0.001) positions.

CONCLUSION

The results of this study suggest that the presence of MTMs increases the incidence of caries on the distal surface of MSMs. Furthermore, caries on the distal surface of MSMs is more commonly associated with position A and horizontal and mesioangular mandibular molars.

Distal caries of the second molar in the presence of a mandibular third molar - a prevention protocol

Objectives The objectives of the prospective study were to establish the prevalence of distal caries (DC) in the mandibular second molar and to assess the outcomes of these diseased teeth in our population. Further aims were to identify associated risk factors and to design a protocol for prevention.Methods Clinical and radiographic data from 210 consecutive patients were ascertained over a three-month period. The sample population included all patients who had been referred to a hospital oral surgery department for a lower wisdom tooth assessment.Results A total of 224 mandibular third molars were included and assessed. The prevalence of caries affecting the distal aspect of the second molar was 38% (n = 85) in this population. In 18% of patients there was evidence of early enamel caries. Fifty-eight percent of caries was managed with restorative treatment but 11% of patients required second molar extraction and 13% of patients required the removal of the second and third molars. The prevalence of distal caries was significantly higher in patients with partially erupted wisdom teeth positioned below the amelocemental junction (P <0.05) of the adjacent second molar and in patients who presented with mesioangular impactions (P <0.001). However there was no difference in dental health when comparing this group to the remaining study population (P = 0.354). The Pearson chi-square test and Pearson correlation coefficient were used to verify the association between the tested variables.Conclusion This study demonstrates that the eruption status, type of angulation and the nature of tooth contact between both molars are useful disease predictors which can be used to indicate the likelihood of a caries process occurring on the distal aspect of the second mandibular molar. If patients' third molar teeth are not removed then consideration needs to be given to prevention and regular monitoring.

Impact of mandibular third molar extraction in the second molar periodontal status: A prospective study

Aim:

The aim of the present study was to assess the periodontal condition and sensitivity of second mandibular molars after the extraction of the adjacent third molar, while also assessing the quality of life of the patients.

Materials and Methods:

Twenty-three healthy patients were assessed in terms of probing depth, gingival height, gingival thickness, dental sensitivity, plaque index and bleeding on probing (adjacent second mandibular molar), before the surgical procedure, as well as 60 and 180 days after the surgery. The following data were also recorded and measured: the position and size of the impacted teeth; the size of the alveoli after surgery and the quality of life of the patient.

Results:

Significant differences were found for probing depth and gingival height before and after 180 days. The plaque index increased significantly after surgery (P = 0.004), as did bleeding on probing. No significant difference was found for the quality of life. The size of the third molar extracted was correlated with bleeding on probing 180 days after the surgery.

Conclusion:

An improvement was noted in the periodontal condition of the second mandibular molars after the extraction, based on the assessments of probing depth and gingival height. The position of the third molar affected the periodontal condition of the second mandibular molar. No alterations were recorded for dental sensitivity or the quality of life after the extraction.

Impacted lower third molars and distal caries in the mandibular second molar. Is prophylactic removal of lower third molars justified?

Background

The objective of this study was to evaluate the association between the presence of mandibular third molars and the occurrence of carious lesions in the distal aspect of the mandibular second molar.

Material and Methods

A retrospective cohort study comprising 327 lower third molars extracted in the Oral Surgery and Implantology Master’s Degree program of the School of Dentistry of the University of Barcelona (Barcelona, Spain) was carried out. A descriptive and bivariate analysis was made. The diagnosis of caries in the second molar and the position of the mandibular third molar were evaluated through panoramic radiographies.

Results

The sample included 203 patients, 94 males (46.3%) and 109 females (53.7%), with a mean age of 26,8 years and 327 lower third molars. The prevalence of second molar distal caries was 25.4% (95% CI= 20.6% to 30.2%). This pathology was significantly more frequent when the third molar was in a horizontal position (27.7%), when the contact point was at (45,8%) or below (47.0%) the cementoenamel junction (CEJ), and when the distal CEJ of the mandibular second molar and the mesial CEJ of the third molar was 7 to 12 mm apart.

Conclusions

Horizontal lower third molars with contact points at or below the CEJ are more likely to produce distal caries in the mandibular second molars. Due to the high prevalence of this pathology (20.6% to 30.2%), a prophylactic removal of lower third molars with the above-mentioned features might be advisable.

Key words:Second molar, caries, third molar, prophylactic removal.

Association between the eruption of the third molar and caries and periodontitis distal to the second molars in elderly patients

The objective of this study was to verify whether caries and periodontal diseases, when present on the distal surface of the second molars (M2s), are associated with the eruption of the third molars (M3s). In this split-mouth study, we evaluated 70 elderly patients with unilateral maxillary or mandibular M3s who presented to the outpatient clinics of two hospitals. Patients underwent comprehensive oral examinations and radiographical measurements, and we assessed the outcomes of periodontal disease and caries. Periodontal measurements included plaque index, bleeding on probing, and periodontal probing pocket depth (PD). Moreover, caries were assessed through visual-tactile examination and radiography. We performed the χ² test to determine factors associated with M3 and non-M3 outcomes. Eighty-one unilateral erupted M3s were observed in the study patients. Both the distobuccal region (p<0.0001) and the distolingual region (p=0.006) had a higher PD on the nonextraction side than the extraction side, and the caries rate was significantly higher on the nonextraction side than on the extraction side (p <0.0001 on M2 with caries and p=0.003 on M2 with distal caries). M3 eruption, at the same or different occlusal plane levels of M2, is a risk factor for periodontal diseases and caries in M2s in elderly patients. M3s may continue to negatively impact dental health well into later life.

Prevalence of Distal Caries in Mandibular Second Molar Due to Impacted Third Molar

INTRODUCTION

A tooth is said to be impacted if it does not reach the occlusal plane even after two-thirds root formation. The aetiology of impacted teeth is varied and multi-factorial. Significant problems associated with impacted teeth include trismus, infection, cervical caries of second molars.

AIM

This study was aimed to assess the prevalence of distal caries in second molar teeth due to impacted third molars and to compare with similar studies conducted elsewhere.

MATERIALS AND METHODS

Study included assessment of patients reporting between 2009 to 2014 for dental care at College of Dentistry, King Khalid University, Abha, Kingdom of Saudi Arabia. This is a retrospective cross-sectional study which included a total of 6000 Orthopantomograms (OPGs). The data collected was decoded and entered into excel spread sheet. Descriptive analysis of the data was done and results were displayed as frequency table and graphs.

RESULTS

A total of 979 patients had impacted third molars (16.31%). A total of 39% patient's with impacted third molars had distal cervical caries in second molar. Mesioangular impaction was the most prominent type. This was closely followed by horizontal impaction causing distal caries in second molars. Age group between 21-28 years and male gender had the higher prevalence of distal caries in second molar teeth due to impacted third molars.

CONCLUSION

A total of 39% of the patients with impacted mandibular third molars had distal cervical caries in second molars. Mesioangular type, male gender, age group 21-28 years were the prominent factors associated with distal caries in second molar teeth due to impacted third molars.

Saving the 2(nd) Molar from the 3(rd) Is it Really the Guilt of the Tilt?

INTRODUCTION

Clinicians often relate the distal caries in second molars to angulated third molars, which if left undetected can lead to gross decay that may further require removal of the tooth. Due to this fact, many third molars are advised for prophylactic removal to prevent decay in the second molar. But this approach would only be justified when the incidence of decay/loss of second molar due to third molar are reasonably high. We sought to determine incidence of caries experience and also sequel extraction in second molars associated with the third molars.

AIM

The study was conducted to answer the basic question that whether the incidence of caries and subsequent extraction of second molar due to angulated third molars is high enough to justify the prophylactic removal of third molar or not.

MATERIALS AND METHODS

This study was conducted on radiographic records of 1187 patients. The effect of tilted third molar on the second molar was measured in relation with three parameters namely level & position of third molar with respect to second molar and the distribution among arches.

RESULTS

The results indicated that out of total number of teeth examined only 5.4% of maxillary and 9.6% of mandibular second molars were affected by tilted third molars. Further, only 2.2% of mandibular and 2.9% of maxillary second molars were indicated for extraction. The data was statistically insignificant.

CONCLUSION

It was concluded that distal caries in second molars is not very common. It may be present in some cases of third molar impactions and prophylactic removal of these impacted teeth may not be considered appropriate.