The Use of a Novel Approach for the Instrumentation of a Cone-beam Computed Tomography-discernible Lateral Canal in an Unusual Maxillary Incisor: Case Report.

Lateral and apical ramifications of the main root canal create potential pathways through which bacteria can spread and remain unaffected by treatment procedures. It is a challenge for the specialty to find techniques that can predictably reach, disinfect, and obturate these ramifications. Here, we report the use of a novel instrumentation approach to aid in the negotiation and management of a lateral canal discernible on cone-beam computed tomography (CBCT) in an unusual maxillary central incisor. A 23-year-old female patient was referred for evaluation and possible treatment of tooth 9. The periapical radiographic examination revealed pulp chamber obliteration, existence of a lateral lesion, and a possible complex internal root canal anatomy. The CBCT evaluation revealed the existence of a lateral lesion, a periapical lesion, an additional distopalatal canal, and a lateral canal exiting at the lateral lesion. The diagnosis of asymptomatic apical and lateral periodontitis of tooth 9 was reached. CBCT-aided access cavity preparation and scouting resulted in the successful negotiation of all canals, main and lateral. A novel instrumentation technique with precurved controlled memory files was used for the mechanical preparation of the lateral canal to a 25/04 enlargement. Obturaton of the lateral canal was achieved with a single gutta-percha cone and AH Plus Root Canal Sealer. At the 2-year follow-up, the patient was asymptomatic, and the 2-dimensional radiographic examinations revealed resolution of both the periapical and the lateral lesions. This case report describes the application of a novel instrumentation technique for the mechanical debridement of an infected lateral canal discernible on CBCT and reinforces the importance of treating the root canals as systems that possesses anatomic intricacies that need to be addressed.

Regenerative endodontic therapy: a data analysis of clinical protocols.

INTRODUCTION: The aim of the present study was to systematically analyze the protocols that have been used in regenerative endodontic therapy and to detect any variations in clinical procedures. METHODS: An electronic search was executed in PubMed using appropriate Medical Subject Heading terms covering the period from January 1993 to May 2014. Additional publications from hand searching and the reference section of each relevant article enriched the article list. The relevance of each article was initially evaluated by scanning all titles and corresponding abstracts. The definite inclusion of each article in the study was determined by using specific criteria applied independently by 3 reviewers. RESULTS: Sixty relevant publications were finally included. The canal walls were not mechanically instrumented in 68% of the clinical articles. Sodium hypochlorite was included in 97% of the clinical studies either as the only irrigant or in combination with other irrigants. Antibiotic combination paste was used as the intracanal medicament in 80% of the clinical articles. Sodium hypochlorite, chlorhexidine, and EDTA were used in the final irrigation protocol in 75%, 4%, and 13% of the clinical studies, respectively. Neither the creation of a blood clot nor the use of platelet-rich plasma/platelet-rich fibrin was described in 13% of the clinical articles. Mineral trioxide aggregate was used as an intracanal coronal barrier in 85% of the relevant clinical studies. CONCLUSIONS: The variability of the clinical protocols applied during regenerative enododontic procedures is considerably high. A thorough analysis of regenerative protocols may constitute an additional source to provide useful clinical considerations for REPs.

A quantitative and diametral analysis of human dentinal tubules at pulp chamber ceiling and floor under scanning electron microscopy.

The purposes of this study are (i) to evaluate and compare the dentinal tubule density, tubule diameter and percentage area of dentin occupied by tubules at the pulp chamber ceiling and floor; and (ii) to evaluate the effects of age on the number and dimensions of tubule openings. Twelve intact, human mandibular third molars were recruited. Six teeth belonged to patients up to 30 years of age and six teeth belonged to patients over 50 years. Scanning electron microscopic evaluations were made at two different locations: the pulp chamber ceiling and floor. The pulp chamber ceiling presented higher tubule density (P < 0.0001) and greater percentage area of dentin occupied by tubule openings (P < 0.0001) compared to the pulp chamber floor. Also, younger age group had greater tubule diameter (P < 0.0001), higher tubule density (P < 0.0001) and greater percentage area of dentin occupied by tubule openings (P < 0.0001) compared to older age group. Pulp chamber ceiling presents higher tubule density and greater area of exposed tubules. In younger people, the pulp chamber floor presents considerably high tubule diameter. The number and dimensions of dentinal tubule openings significantly decrease with age.

Levels of evidence for the outcome of regenerative endodontic therapy.

INTRODUCTION: The aim of this systematic review was to assign levels of evidence (LOEs) to existing clinical articles related to the outcome of regenerative endodontic therapy and to evaluate the clinical and radiographic outcomes of this treatment modality. METHODS: Electronic search was executed in PubMed, Scopus, and Cochrane databases by using appropriate Medical Subject Headings terms covering the period from January 1993 to December 2013. Additional publications from hand-searching and reference section of each relevant article enriched the article list. The LOE of each article was assessed according to guidelines provided by the Oxford Centre of Evidence-Based Medicine. Quality assessment of the observational studies was executed by using the Newcastle-Ottawa scale. RESULTS: Fifty-one relevant publications were included in this review. There were 2 high-level cohort studies (LOE 2), 8 case series (LOE 4), and 41 case reports (LOE 5). The vast majority of the treated teeth in those publications showed resolution of clinical signs, symptoms, and periapical radiolucencies at follow-up period. Furthermore, the majority of treated teeth presented further increase in root length and root wall thickness and apical closure at the follow-up period. However, because of lack of sufficient high-level evidence it was not possible to answer totally the review question and determine definitely the outcome of regenerative endodontic therapy. CONCLUSIONS: The lack of adequate high-level studies that could possibly strengthen the satisfactory current data and allow practicing more evidence-based dentistry constitutes a significant knowledge gap in the endodontic literature. However, the current best available evidence undeniably allows clinicians to provide this treatment modality safely to patients.

Estimation of radiographic angles and distances in coronal part of mandibular molars: A study of panoramic radiographs using EMAGO software.

OBJECTIVE: This study was designed to investigate radiographically the effects of age and external irritating stimuli on the morphology and thickness of the pulp chamber ceiling and floor in mandibular molars. MATERIALS AND METHODS: A total of 234 panoramic radiographs were recruited and 494 mandibular molars were examined in this study. The sample was divided into six age groups: Group 1, <20 years; Group 2, 20-29 years; Group 3, 30-39 years; Group 4, 40-49 years; Group 5, 50-59 years and Group 6, >60 years. Each group was subdivided into two subgroups with regard to the tooth condition (intact or non-intact teeth). Four distances, two angles and two ratios were measured, in order to estimate the dimensions of the pulp chamber and the thickness of the pulp chamber ceiling and floor. RESULTS: The thickness of the pulp chamber ceiling and floor increased significantly from Group 1 to 6. The pulp chamber floor angle presented progressive sharpness from Group 1 to 6 whereas the pulp chamber ceiling angle presented progressive bluntness from Group 1 to 5 and sharpness from Group 5 to 6. Significant differences were identified in the thickness of the pulp chamber ceiling, the thickness of the pulp chamber floor and the ceiling-floor distance between intact and non-intact teeth. CONCLUSION: Based on those results, there are differences in the location of secondary dentin formation between the two pulp chamber walls. Age is related to diminished pulp chamber size. The increase rate of the pulp chamber ceiling thickness is similar to that of the pulp chamber floor thickness. Furthermore, external irritating stimuli have an effect on the pulp chamber dimensional changes.

The variability of electric pulp response threshold in premolars: a clinical study.

INTRODUCTION: This study was designed to determine the variability of the electric pulp response threshold in premolars and the relationship between the response threshold and age. METHODS: Ninety-seven volunteers were recruited, ranging from 20-72 years old. The volunteers were categorized into 6 age groups: group 1, 20-29 years; group 2, 30-39 years; group 3, 40-49 years; group 4, 50-59 years; group 5, 60-69 years; and group 6, 70-79 years. All intact premolars present in each dental arch were tested. Three sites (the tip of the buccal cusp, the center of the middle, and cervical third of the buccal surface) on each tooth crown were tested. RESULTS: In total, 1965 measurements were done. A progressive increase of mean threshold value was observed from groups 1 to 6. The response threshold value showed significant differences among the 6 age groups. The effect of age was more intense in mandibular premolars. In first and second mandibular premolars the cusp tip required the lowest current to evoke a response. In maxillary premolars no significant differences among the sites were found. Also, the mean threshold value of the mandibular premolars was lower than that of the maxillary premolars in subjects of the same age, and the mean threshold value of the first premolars was lower than that of the second premolars. The buccal cusp tip of the first mandibular premolars responded more quickly than any other tested site. CONCLUSIONS: Age is related with higher response threshold values. The optimum site for testing the lower premolars is the buccal cusp tip.