Root resection under the surgical field employed for extraction of impacted tooth and management of external resorption

Review of Approaches to the Management of Vertical Dental Root Fractures and Tooth Preservation

A vertical root fracture (VRF) is a complex condition in which the fracture lines can be partial or complete and extend along the long axis of the tooth. Considering the nature of the damage and the low likelihood of a successful outcome, such fractures can be difficult to manage. Their management typically involves complex endodontic or surgical procedures, which can be technically challenging for general dentists. Recent advancements introduce promising techniques, such as intentional replantation, adhesive methodologies, and regenerative procedures, showcasing potential in salvaging teeth affected by VRFs. Nonetheless, the imprecise nature of symptoms necessitates meticulous case evaluation by clinicians. Comprehensive patient counseling regarding diverse treatment options and potential ramifications remains crucial to preserving the affected tooth. Preserving a vertically fractured tooth aids in improving both function and aesthetics while safeguarding the arch's integrity by maintaining the height of the alveolar bone. It is important to note that the success of the treatment procedures depends on the extent and location of the fracture, the condition of the tooth and fragment, and the skill of the dental professional performing the treatment. This review highlights the complexity of VRF management, emphasizing the necessity for precise evaluation, patient education, and the exploration of innovative techniques. It aims to review the treatment of VRFs, ranging from classical to contemporary methods, with a focus on tooth preservation. The establishment of standardized protocols and conduct of further research to ascertain long-term efficacy are imperative in optimizing outcomes and retaining natural dentition in cases of VRFs.

Could the pulp be preserved in tooth with root resorption caused by embedded tooth?

Background/purpose

At present, there are no recognized guidelines or consensus for the treatment strategy of the asymptomatic tooth with external root resorption caused by an embedded tooth (et-ERR). Most clinicians would like prophylactic or concomitant root canal therapy (RCT) along with the extraction of the embedded tooth. The purpose of this study was to report the prognosis of external root resorption (ERR) and investigate the possibility to preserve the vital pulp of ERR tooth.

Materials and methods

The patients who had asymptomatic et-ERR teeth were included. After extraction of the embedded tooth, the clinical process, prognosis, and adverse events were observed, including symptoms, clinical, and radiographic examination throughout the follow-up period.

Results

A total of four cases with special features were reported. Over a follow-up period of up to 12 months, on clinical examination, 3 ERR teeth preserved pulp vitality without additional intervention except for tooth extraction and have kept normal function free from any symptoms. Radiographic examination showed bone regeneration and recovery of periodontal tissue. While one case failed to keep the vital pulp and ended in intentional replantation.

Conclusion

As to et-ERR, if the embedded tooth can be promptly extracted with a minimally invasive technique and effective infection control, the pulp vitality of the et-ERR tooth is likely to be preserved. In this situation, the preferred management of asymptomatic et-ERR tooth is just followed up without prophylactic RCT.

Combined micro-apical surgery and vital pulp therapy in mandibular second molars with external root resorption caused by impacted teeth

OBJECTIVES

This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps.

METHODS

For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted.

RESULTS

The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis.

CONCLUSIONS

Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.

Analysis of External Root Resorption of the Second Molar Associated with an Impaction of the Third Molar by the Application of CBCT

External root resorption (ERR) of a tooth represents a process in which irreversible damage occurs to solid dental tissues, more precisely of the cement and dentin. External resorption occurs on the root surface or periodontal ligament, and it is manifested by the loss of cement and/or dentine. The prevalence of ERR of the second molar associated with an impacted third molar, based on retro-alveolar radiography and orthopantomography, ranges from 0.3% to 24.2%. The aim of this research was to analyze ERR of the upper and lower jaw associated with the impacted third molar by the application of the Come Beam Computed Tomography. This study included 96 third molars in the upper and lower jaw of a total of 46 analyzed patients’ images. Total prevalence of the second molar ERR associated with the impacted third molar was 8.82%. The second molar ERR was observed in 8 patients (7.84%). Frequency of the second molar ERR in the lower jaw is higher, and it is 8.2%, while in the upper jaw it is only 1% (r = 0.032). Impacted third molars associated with the second molar ERR were most frequently in horizontal (5.1%) and mesioangular (4.1%) position (p = 0.000). The second molar ERR could be avoided by the preventive extraction of mesioangular or horizontal third molars. An adequate decision on the extraction of impacted third molars must be made by the careful assessment of risks and benefits of this surgical intervention. Before the surgical intervention, an adequate care of the second molar, adequate restoration, endodontic treatment or root resection should be done if necessary.

[Prognosis of teeth with external root resorption caused by adjacent impacted teeth]

OBJECTIVE

This study aimed to investigate the prognosis of permanent teeth with external root resorption (ERR) caused by adjacent impacted teeth.

METHODS

A total of 75 ERR teeth (permanent teeth) caused by adjacent impacted teeth of 63 patients were included. The prognosis of ERR teeth was analyzed followed by minimally invasive extraction of the adjacent impacted teeth. The time of follow-up was six months. The relationship between prognosis of ERR teeth and patients' age, gender, root number, type of root resorption and degree of root resorption were analyzed.

RESULTS

In the 75 ERR teeth, 67 teeth (89.3%) did not show pulpitis symptoms. The clinical outcome was found to be related with age (r=0.330, P<0.05), whereas no relationships with gender, root number, as well as type and degree of root resorption were observed (P>0.05). Pulpitis symptom was not found in ERR teeth of patients under 30 years old.

CONCLUSIONS

For ERR teeth caused by adjacent impacted teeth, keeping the pulp vital after surgical removal of impacted teeth is highly probable. Post-operative follow-up instead of preventive root canal therapy of ERR teeth is recommended.

Resorptive potential of impacted mandibular third molars: 3D simulation by finite element analysis

OBJECTIVES

Previous studies have suggested a relationship between resorption in second molars and pressure from the eruptive force of the third molar. The aim of this study was to simulate functional forces in a mandible model by means of finite element analysis and then assess the biomechanical response produced by impacted third molars on the roots of the second molar.

MATERIALS AND METHODS

A cone beam computed tomography scan presenting an impacted mandibular third molar was segmented (Mimics V17 software). The modeling process was performed using the reverse engineering technique provided by the Rhinoceros 3D 5.0 software. The third molar position was changed in order to produce different inclinations of the impacted tooth. Bite forces were simulated to evaluate total deformation, the equivalent von Mises stress, minimum principal stress on hard tissue, and equivalent elastic strain on soft tissue.

RESULTS

Areas of high energy dissipation and compression stress were detected in the second molar root, independently of the inclination of the impacted third molar. In general, the horizontal position was the situation in which major stress and the amount of deformation occurred in the second and third molar regions.

CONCLUSION

Impacted third molars in close proximity with the adjacent tooth can generate areas of compression concentrated at the site of contact, which suggests an involvement of mechanical factors in the triggering of resorption lesions.

CLINICAL RELEVANCE

The results of these computational experiments contribute to the understanding of the triggering and progression of resorptive lesions in the adjacent second molar.

Correlational study of impacted and non-functional lower third molar position with occurrence of pathologies

Background

Lower third molar (M3) eruption is unpredictable. The purpose of this study was to correlate radiographic position of M3 on a preexistent film with the current clinical, histopathological, and radiographic findings.

Methods

A retrospective cohort study was performed. The sample was collected from a database of patients covered by Medical Fund of Brazilian Army. Radiographs were obtained a minimum of 5 years prior to the presurgical visit and after their clinical exam. The primary outcome variables were the teeth positions using Pell and Gregory/Winter classifications on panoramic X-rays. Those variables were analyzed at both the beginning (T0) and end of the study (T1). Clinical assessments and histopathological study of the thirds that were extracted were performed only at T1. Correlation between the teeth positions were related to the clinical, histopathological, and radiographic parameters using statistical analysis tests with significance set at p < 0.05.

Results

Twenty-six patients with 49 M3 were assessed over 10 months. Mean age was 14.92 years at T0 and 21.87 years at T1. The average time between T0 and T1 was 6.77 years. A significant relationship (p = 0.024) was found between the presences of root resorption on the second molar if M3 presented in an IB horizontal position at T1. There was also a significant correlation (p = 0.039) between dental crowding of the anterior lower teeth with IIIB position at T0 and if the patient finished orthodontic treatment without lingual retainers.

Conclusions

Lower M3 in position IIIB seen in a teenager and IB seen in an adult is more likely to have negative consequences and should be followed closely.

External root resorption of the second molar associated with third molar impaction: comparison of panoramic radiography and cone beam computed tomography

PURPOSE

The aim of the present study was to compare panoramic radiography and cone beam computed tomography (CBCT) for the assessment of external root resorption (ERR) of second molars associated with impacted third molars. In addition, the prevalence of ERR in second molars and the inclinations of the third molars more associated with ERR were investigated in both imaging methods.

MATERIALS AND METHODS

The sample consisted of 66 individuals with maxillary and mandibular impacted third molars (n = 188) seen on panoramic radiographs and CBCT images. The presence of ERR on the adjacent second molar was investigated, and the position of the third molar was determined using Winter's classification (vertical, horizontal, mesioangular, distoangular, and transverse). Statistical analysis was performed using the χ(2) test, Fisher exact test, and 2-proportion Z test (the significance level was set at 5%).

RESULTS

A significantly greater number of cases of ERR (P < .0001) was diagnosed from CBCT images (n = 43, 22.88%) than panoramic radiographs (n = 10, 5.31%). The agreement between the panoramic radiographs and CBCT scans for diagnosing ERR was 4.3%. Mandibular third molars in mesioangular and horizontal inclinations were more likely to cause resorption of the adjacent teeth.

CONCLUSIONS

CBCT should be indicated for the diagnosis of ERR in second molars when direct contact between the mandibular second and third molars has been observed on panoramic radiographs, especially in mesioangular or horizontal impactions. Furthermore, considering the propensity of these teeth to cause ERR in second molars, third molar prophylactic extraction could be suggested.