Dens invaginatus is a rare developmental anomaly of the teeth that is caused by the infolding of enamel organs or the penetration of their proliferations into dental papillae before calcification has occurred. The presence of double dens invaginatus is extremely rare. This paper describes the use of cone beam computed tomography in the evaluation of a maxillary lateral incisor with double dens invaginatus and periapical periodontitis. The tooth was treated through microscopic root canal therapy. The tooth was free of clinical symptoms, and the periradicular lesion narrowed during the follow-up period of 1 year.
Humans ; Dental Pulp Cavity/abnormalities* ; Dens in Dente/pathology* ; Incisor/pathology* ; Root Canal Therapy ; Periapical Periodontitis/pathology*

There is a high incidence of chronic periapical periodontitis of deciduous teeth, however, there is a low incidence of the apical cyst. This paper reports a 7-year-old child with deciduous periodontitis caused by chronic periapical periodontitis of deciduous teeth. Through literature review, the etiology, imaging characteristics, diagnosis, differential diagnosis, and treatment methods were discussed to provide the basis for clinical diagnosis and treatment.
Child ; Humans ; Cysts ; Diagnosis, Differential ; Periapical Periodontitis/therapy* ; Tooth, Deciduous

Palatal radicular groove is a developmental malformation of maxillary incisors, lateral incisors in particular, which often causes periodontal destruction. This paper reports a case of combined periodontal-endodontic lesions induced by palatal radicular groove, which was initially misdiagnosed as a simple periapical cyst. After root canal therapy and periapical cyst curettage, the course of disease was prolonged, resulting in the absence of buccal and maxillary bone plates in the affected tooth area. After the etiology was determined, the affected tooth was extracted and guide bone tissue regeneration was performed at the same time, followed by implantation and restoration at the later stage, leading to clinical cure. The palatal radicular groove is highly occult, and the clinical symptoms are not typical. If the abscess of the maxillary lateral incisor occurs repeatedly, and the abscess of the maxillary lateral incisor has not been cured after periodontal and root canal treatment, cone-beam computed tomographic and periodontal flap surgery should be considered.
Humans ; Incisor ; Radicular Cyst ; Abscess ; Tooth Root/abnormalities* ; Root Canal Therapy ; Maxilla ; Cysts

Bacterial infection is a common finding in patients, who develop medication-related osteonecrosis of the jaw (MRONJ) by the long-term and/or high-dose use of anti-resorptive agents such as bisphosphonate (BPs). However, pathological role of bacteria in MRONJ development at the early stage remains controversial. Here, we demonstrated that commensal microbiota protects against MRONJ development in the pulp-exposed periapical periodontitis mouse model. C57/BL6 female mice were treated with intragastric broad-spectrum antibiotics for 1 week. Zoledronic acid (ZOL) through intravenous injection and antibiotics in drinking water were administered for throughout the experiment. Pulp was exposed on the left maxillary first molar, then the mice were left for 5 weeks after which bilateral maxillary first molar was extracted and mice were left for additional 3 weeks to heal. All mice were harvested, and cecum, maxilla, and femurs were collected. ONJ development was assessed using μCT and histologic analyses. When antibiotic was treated in mice, these mice had no weight changes, but developed significantly enlarged ceca compared to the control group (CTL mice). Periapical bone resorption prior to the tooth extraction was similarly prevented when treated with antibiotics, which was confirmed by decreased osteoclasts and inflammation. ZOL treatment with pulp exposure significantly increased bone necrosis as determined by empty lacunae and necrotic bone amount. Furthermore, antibiotics treatment could further exacerbate bone necrosis, with increased osteoclast number. Our findings suggest that the commensal microbiome may play protective role, rather than pathological role, in the early stages of MRONJ development.
Animals ; Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control* ; Bone Density Conservation Agents ; Diphosphonates ; Female ; Humans ; Mice ; Microbiota ; Periapical Diseases ; Zoledronic Acid

Root canal therapy is the common treatment for endodontic infections. Successful root canal therapy depends on favorable root canal preparation, root canal medication and three-dimensional obturation of the root canal system. The key to successful root canal therapy is to prevent re-infection of the highly complex root canal systems by removing infecious biofilms and bacterial toxins in the root canal system. The present paper reviews the pathogenic mechanism of the Enterococcus faecalis in the harsh environment of root canal system, the inflammation and immunity of refractory periapical periodontitis and the progress of infection control methods.
Dental Pulp Cavity ; Enterococcus faecalis ; Humans ; Periapical Periodontitis/therapy* ; Persistent Infection ; Root Canal Irrigants ; Root Canal Preparation ; Root Canal Therapy

Root canal therapy and endodontic surgery are conventional treatments for pulpal and periapical diseases. Compared with naked-eye operations, the application of dental operating microscope has enhanced the procedural accuracy and prognosis efficiently. However, root canals with pulp calcification/obliteration, apical lesions with thick cortical bone or adjacent to important anatomic structures are even challenging for experienced operators to achieve predictable clinical outcomes. Recently, with the advances in the field of digitalized information sciences, the above mentioned complicated endodontic cases can be solved under static and dynamic guidance. Before the treatment begins, virtual path is designed from data collected by cone-beam CT and oral image scanning using guidance software. Afterwards, root canal therapy and endodontic surgery can be performed precisely under the assistance of three-dimensional printed guide or dynamic guidance system. The present review describes the classification, features and clinical applications of the guided endodontics.
Cone-Beam Computed Tomography ; Dental Pulp Cavity ; Endodontics ; Humans ; Periapical Diseases/diagnostic imaging* ; Root Canal Therapy

Conservative Treatment ; Dens in Dente/therapy* ; Humans ; Incisor ; Periapical Periodontitis/therapy* ; Root Canal Filling Materials

Pulp and periapical diseases are common and frequently occurring diseases of which diagnosis and treatment must be dealt with by the dental clinicians. The diagnostic techniques of these diseases include evaluation of pulp vitality, measurement of pulp blood circulation and analysis and judgment of root canal anatomy. With the continuous emergence of digital and imaging technologies, the correct application of these technologies in clinic will help clinicians improve their abilities in diagnosis and treatment of related diseases. The present article summarizes and reviews the progress of assistant technology for diagnosing dental pulp and periapical diseases in recent years and puts forward some suggestions for its application.
Humans ; Periapical Diseases/diagnostic imaging* ; Root Canal Therapy/methods*

To assess the treatment effectiveness of vital inflamed pulp therapy (VIPT) in immature permanent teeth with irreversible pulpitis and apical periodontitis. The faculty members in the Department of Pediatric Dentistry, the Ninth People's Hospital were invited to submit consecutive VIPT cases from June 2015 to June 2016 (follow-up periods>12 months). The cases were retrospectively reviewed, clinical symptoms and radiographic changes in periapical radiolucency were evaluated, meanwhile, the data of radiographic changes such as apical diameter and root length were calculated and analyzed with ANOVA. Totally thirteen submitted patients/cases were included (6 males and 7 females) in the present study,. The average age of patients was (9.9±1.4) years old. The average follow-up time was (26.5±6.8) months (17-37 months). At the 12-month visit, all 13 treated teeth survived, 9 out of 11 teeth with apical periodontitis showed normal radiographic manifestation. At the 3, 6 and 12 months visits, the within-case percentage changes in apical diameter were (8.0±5.1)%, (24.1±9.1)% and (70.3±10.7)%, respectively, while the within-case percentage changes in root length were (11.4±9.8)%, (14.5±9.8)% and (27.4±14.2)%, respectively. There were statistically significant differences in the changes of apical diameter (F=18.80, P<0.001) and root length (F=4.64, P=0.047) from the preoperative time to the postoperative follow-ups. VIPT might improve clinical outcomes, even achieve continued root development. VIPT can be an option in treating immature teeth with irreversible pulpitis and apical periodontitis.
Child ; Dentition, Permanent ; Female ; Humans ; Male ; Periapical Periodontitis/therapy* ; Pulpitis/therapy* ; Retrospective Studies ; Root Canal Therapy

OBJECTIVE: To analyze the three-dimensional radiographic characteristics of maxillary radi-cular cysts using cone-beam computed tomography (CBCT) and spiral CT. METHODS: Clinical records, histopathological reports, and CBCT or non-enhanced spiral CT images of 67 consecutive patients with maxillary radicular cysts were retrospectively acquired, and radiographic features, including size, shape, expansion, internal structure and relationship with the surrounding tissues, were analyzed. The lesions were divided into three types according to the involved tooth number, as follows: type Ⅰ (single tooth), the epicenter of the cyst was located at the apex of a nonvital tooth, without involvement of the neighbo-ring tooth; type Ⅱ (adjacent tooth involvement), the cyst was located at the apex of a nonvital tooth with involvement of the mesial and/or distal tooth root; and type Ⅲ (multi-teeth), the cyst involved the apexes of ≥4 teeth. Besides, these cysts were classified as another three types on sagittal views, as follows: centripetal, the root apex was oriented centripetally to the center of the cyst; palatal, the cyst was located mainly at the palatal side of the apex; and labial/buccal, the cyst was located mainly at the labial/buccal side of the apex. RESULTS: Totally, 67 patients with maxillary radicular cysts were acquired, including 38 males and 29 females, and their ages ranged from 13 to 77 years. Among them, 46 lesions (68.7%) were located in the anterior maxilla and 65 (97.0%) were round or oval. Labial/buccal cortex expansion was present in 43 cases (64.2%) and palatal cortex expansion in 37 cases (55.2%). The nasal floor was invaded in 27 cases (40.3%), the maxillary sinus was invaginated in 26 cases (38.8%), and root resorption was present in 9 cases (13.4%). The average diameter of lesions was (20.89±8.11) mm mesio-distally and (16.70±5.88) mm bucco-palatally. In spite of the 4 residual cysts, the remaining 63 lesions included 14 type Ⅰ, 26 type Ⅱ and 23 type Ⅲ cysts according to the involved tooth number. Besides, the 63 lesions included 46 centripetal, 15 palatal and 2 buccal cysts on sagittal views. CONCLUSION The maxillary radicular cysts were frequently well-circumscribed round or oval radiolucency, with significantly different sizes. According to the involved tooth number, it can be divided into single tooth, adjacent tooth involvement and multi-teeth types. On sagittal views, the root-cyst relationship was centripetal in most cases, while a minority of cysts expanded palatally or buccally.
Adolescent ; Adult ; Aged ; Cone-Beam Computed Tomography ; Female ; Humans ; Male ; Maxilla/diagnostic imaging* ; Middle Aged ; Radicular Cyst/diagnostic imaging* ; Retrospective Studies ; Tooth Root ; Young Adult