Analysis of clinical associated factors of vertical root fracture cases found in endodontic surgery.

BACKGROUND/PURPOSE: Early diagnosis of vertical root fracture (VRF) has been a great challenge. Since there is no single specific etiology identified, prevention of VRFs in endodontically treated teeth is quite difficult. The study aimed to evaluate the clinical associated factors of VRFs. MATERIALS AND METHODS: A retrospective observational study of medical charts was conducted in the Department of Endodontics of Taipei Medical University Hospital in Taiwan from January 2012 to July 2018. Logistic regression model was performed to determine the association between VRF and its clinical associated factors, inclusive of the tooth characteristics (age, gender and tooth type) and iatrogenic risk factors (history of root canal treatment, restoration and post). RESULTS: A total of 359 teeth were included in the study. The prevalence of VRF on a tooth basis was 18.7%. The result showed that age of more than 50 years (adjusted OR = 3.20, 95% CI: 1.81-5.64, p < 0.001) had significant higher risk of VRFs than those of less than 50 years. The subjects of molars (adjusted OR = 4.31; 95%CI = 2.24-8.27; P value < 0.001) and premolars (adjusted OR = 2.61; 95%CI = 1.16-5.86; P value = 0.021) had significant higher risk of VRFs than those of incisors. However, other variables such as gender, history of root canal treatment, restoration and post had no significant association with the VRF. CONCLUSION: Age and tooth type are significant clinical associated factors of VRF. In the presence of these factors as well as predominant diagnostic factors, clinical practitioners should be aware of the possible diagnosis of VRFs.

Outcomes of necrotic immature open-apex central incisors treated by MTA apexification using poly(ε-caprolactone) fiber mesh as an apical barrier.

BACKGROUND/PURPOSE: Although unset mineral trioxide aggregate (MTA) has some cytotoxicity, MTA is still a biocompatible material suitable for doing apexification. This study assessed the outcomes for 8 necrotic immature open-apex permanent maxillary central incisors treated by MTA apexification using poly(ε-caprolactone) fiber mesh (PCL-FM) as an apical barrier (so-called PCL-FM/MTA apexification) to prevent extrusion of MTA materials into the periapical tissues of open-apex teeth. METHODS: Eight necrotic immature open-apex permanent maxillary central incisors with the open apices measuring 2.5 mm-3.5 mm in diameter in 8 patients (6 boys and 2 girls; age range, 8-10 years) were first cleaned using ultrasonic activated irrigation with 2.5% sodium hypochlorite solution and then treated by PCL-FM/MTA apexification procedure. RESULTS: All the 8 permanent maxillary central incisors showed successful outcomes after PCL-FM/MTA apexification procedure. The mean duration for apical hard tissue barrier formation of the 8 incisors was 6.8 ± 0.5 weeks (range 6-7 weeks). The mean increased root length was 1.8 ± 0.7 mm (range 1-3 mm) at 7 weeks and 3.1 ± 0.6 mm (range 2-4 mm) at 3 months. The mean increased dentinal wall thickness at the most apical portion of the root was 1.3 ± 0.5 mm (range 1-2 mm) at 7 weeks and 2.4 ± 0.6 mm (range 1.5-3 mm) at 3 months. None of the teeth treated by PCL-FM/MTA apexification showed tooth discoloration after a follow-up period of 3 months. CONCLUSION: PCL-FM/MTA apexification is an excellent technique for treatment of necrotic immature open-apex permanent maxillary central incisors.

The association between clinical diagnostic factors and the prevalence of vertical root fracture in endodontic surgery.

BACKGROUND/PURPOSE: Diagnosis of vertical root fractures (VRFs) can often be challenging due to the similarity of signs and symptoms with other common dental infectious diseases. This study was aimed at evaluating the potential relationship between VRFs and commonly used clinical diagnostic factors. METHODS: 330 root-filled teeth with endodontic failures were subjected to endodontic microsurgery over a six-year period. VRFs were identified in 61 teeth. A randomly age- and sex-matched retrospective case-control study was conducted on a subset of 59 root-filled teeth with VRFs (cases) and 177 root-filled teeth without VRFs (controls). The strength of association between preoperative signs and radiographic findings and VRFs was evaluated using logistic regression model. RESULTS: Sinus tract, periodontal pocket depth ≥5 mm, periodontal swelling or abscess, and radiological image of J-shaped or "halo" radiolucency were significantly more frequent in cases than in controls (p < 0.05). With regard to logistic regression analysis, J-shaped or "halo" radiolucency demonstrated the greatest association with VRF, followed by periodontal pocket depth ≥5 mm, sinus tract, and periodontal swelling or abscess. Approximately 70% of cases manifested themselves as combinations of at least two of these factors. Teeth having two and three or four of these factors had 3.14 times and 11.64 times higher risks for the presentations of VRFs, respectively (p < 0.001). CONCLUSION: The major risk for VRFs was represented by those presenting radiological image of J-shaped or "halo" radiolucency, periodontal pocket depth ≥5 mm, sinus tract, and periodontal swelling or abscess simultaneously.

Oxygen-implanted induced formation of oxide layer enhances blood compatibility on titanium for biomedical applications.

Titanium dioxide (TiO2) layers were prepared on a Ti substrate by using oxygen plasma immersion ion implantation (oxygen PIII). The surface chemical states, structure, and morphology of the layers were studied using X-ray photoelectron spectroscopy, X-ray diffraction, Raman microscopy, atomic force microscopy and scanning electron microscope. The mechanical properties, such as the Young's modulus and hardness, of the layers were investigated using nanoindentation testing. The Ti(4+) chemical state was determined to be present on oxygen-PIII-treated surfaces, which consisted of nanocrystalline TiO2 with a rutile structure. Compared with Ti substrates, the oxygen-PIII-treated surfaces exhibited decreased Young's moduli and hardness. Parameters indicating the blood compatibility of the oxygen-PIII-treated surfaces, including the clotting time and platelet adhesion and activation, were studied in vitro. Clotting time assays indicated that the clotting time of oxygen-PIII-treated surfaces was longer than that of the Ti substrate, which was associated with decreased fibrinogen adsorption. In conclusion, the surface characteristics and the blood compatibility of Ti implants can be modified and improved using oxygen PIII.

Repair of a perforating internal resorption: two case reports.

Internal resorption is a rare condition in permanent teeth, and may result from trauma, caries, or restorative procedures. Internal resorption is usually asymptomatic and is first identified as a round-shaped enlargement of a root-canal space on routine radiographs. Large resorption defects may result in penetration of the tooth into the periodontium through the cementum. The gold-standard treatment consists of debridement and obturation of the pulp space, sealing of the external communication, and restoration of the normal function of the tooth through a nonsurgical or surgical method. In this case presentation, we report on two methods for repair of internal resorption with perforation. The first method consisted of treating the lower right second premolar by conventional endodontic therapy under a microscope, followed by repair with mineral trioxide aggregate. The second method consisted of surgical treatment of the upper right central incisor. The choice of treatment depends on the size of the perforation, its location, and the ability to approach it for repair.

Clinical outcomes for teeth treated with electrospun poly(ε-caprolactone) fiber meshes/mineral trioxide aggregate direct pulp capping.

INTRODUCTION: Mineral trioxide aggregate (MTA) is a biocompatible material for direct pulp capping. This study was designed to compare the clinical outcomes of pulp-exposed teeth treated with either poly(ε-caprolactone) fiber mesh (PCL-FM) as a barrier for MTA (so-called PCL-FM/MTA) or MTA direct pulp capping. METHODS: Sixty human vital teeth were evenly divided into 4 groups (n = 15 in each group). Teeth in groups 1 and 3 had pulp exposure <1 mm in diameter, whereas teeth in groups 2 and 4 had pulp exposure of 1-1.5 mm in diameter. Teeth in groups 1 and 2 were treated with PCL-FM/MTA direct pulp capping, and those in groups 3 and 4 were treated with MTA direct pulp capping. RESULTS: Teeth treated with PCL-FM/MTA direct pulp capping needed a significantly shorter mean duration for dentin bridge formation than teeth treated with MTA direct pulp capping. Moreover, teeth with pulp exposure <1.0 mm in diameter needed a significantly shorter mean duration for dentin bridge formation than teeth with pulp exposure of 1-1.5 mm in diameter after either PCL-FM/MTA or MTA direct pulp capping treatment. In addition, teeth treated with PCL-FM/MTA direct pulp capping formed an approximately 3-fold thicker dentin bridge than teeth treated with MTA direct pulp capping 8 weeks or 3 months later. Furthermore, none of the teeth treated with PCL-FM/MTA direct pulp capping showed tooth discoloration after treatment for 3 months. CONCLUSIONS: PCL-FM/MTA is a better combination material than MTA alone for direct pulp capping of human permanent teeth.

Comparison of clinical outcomes for 40 necrotic immature permanent incisors treated with calcium hydroxide or mineral trioxide aggregate apexification/apexogenesis.

BACKGROUND/PURPOSE: Traumatic injury often results in pulp necrosis of immature permanent incisors in children. This study compared clinical outcomes for 40 necrotic immature permanent incisors treated with calcium hydroxide [Ca(OH)2] or mineral trioxide aggregate (MTA) apexification/apexogenesis. METHODS: Forty necrotic open-apex incisors from 40 children aged 6.5-10 years were divided evenly into four groups with each group containing teeth of similar type and similar root apex width in patients of similar age. Group 1 incisors were treated with ultrasonic filing and MTA placement; Group 2 were treated with ultrasonic filing and Ca(OH)2 medication; Group 3 were treated with hand filing and MTA placement; and Group 4 were treated with hand filing and Ca(OH)2 medication. RESULTS: Group 1 incisors needed the shortest mean duration (5.4 ± 1.1 weeks) for apical hard tissue barrier formation, followed by Group 3 incisors (7.8 ± 1.8 weeks), Group 2 incisors (11.3 ± 1.3 weeks), and Group 4 incisors (13.1 ± 1.5 weeks). Group 1 incisors had a significantly shorter mean elongated root length (2.1 ± 0.2 mm) after treatment than Group 2 incisors (3.5 ± 0.3 mm, p < 0.001), and Group 3 incisors had a significantly shorter mean elongated root length (2.1 ± 0.1 mm) after treatment than Group 4 incisors (3.7 ± 0.3 mm, p < 0.001). CONCLUSION: Necrotic open-apex incisors treated with ultrasonic filing plus MTA placement need the shortest mean duration for apical hard tissue barrier formation. For elongation of apical root length, Ca(OH)2 apexification/apexogenesis is better than MTA apexification/apexogenesis, regardless if either ultrasonic or hand filing are used.