The Effect of Pulp Obliteration on Pulpal Vitality of Orthodontically Intruded Traumatized Teeth

Negotiation of Calcified Canals

The gradual formation of hard tissue along the root canal walls is a natural process associated with aging, typically progressing slowly over time. In reaction to tooth wear, operative procedures, vital pulp treatments, or regenerative endodontic procedures, hard tissue may also accumulate within the pulp canal space at a slow rate. In certain cases, such as dental trauma, autotransplantation, or orthodontic treatment, this deposition of hard tissue can accelerate unexpectedly, resulting in rapid narrowing or complete closure of the root canal space. This situation is called calcific metamorphosis (CM), root canal calcification, or pulp canal obliteration (PCO). Performing conventional endodontic therapy on severely calcified canals presents significant challenges and increases the risk of procedural accidents. Calcified canals introduce such complexity that dedicated negotiation concepts and specially designed instruments have been developed to deal with the challenge. This article seeks to review the existing methods for effectively navigating calcified canals and to introduce the buckling resistance activation test (BRAT) technique.

Expert consensus on digital guided therapy for endodontic diseases

Digital guided therapy (DGT) has been advocated as a contemporary computer-aided technique for treating endodontic diseases in recent decades. The concept of DGT for endodontic diseases is categorized into static guided endodontics (SGE), necessitating a meticulously designed template, and dynamic guided endodontics (DGE), which utilizes an optical triangulation tracking system. Based on cone-beam computed tomography (CBCT) images superimposed with or without oral scan (OS) data, a virtual template is crafted through software and subsequently translated into a 3-dimensional (3D) printing for SGE, while the system guides the drilling path with a real-time navigation in DGE. DGT was reported to resolve a series of challenging endodontic cases, including teeth with pulp obliteration, teeth with anatomical abnormalities, teeth requiring retreatment, posterior teeth needing endodontic microsurgery, and tooth autotransplantation. Case reports and basic researches all demonstrate that DGT stand as a precise, time-saving, and minimally invasive approach in contrast to conventional freehand method. This expert consensus mainly introduces the case selection, general workflow, evaluation, and impact factor of DGT, which could provide an alternative working strategy in endodontic treatment.

Long-Term Clinical and Radiographic Observation of Previously Regenerated Treated Incisors Subjected to Orthodontic Movement. A Case Series

INTRODUCTION

With an increasing number of anterior traumatized teeth treated with regenerative endodontic procedures (REPs) nowadays, orthodontic movement of such teeth is expected to become a common scenario in everyday clinical practice. However, little is known about the clinical implications and the response capacity of regenerated tissues to orthodontic forces.

METHODS

The aim of this clinical article was to report on 4 cases of REP-treated immature anterior permanent teeth subjected to orthodontic forces, and to describe the long-term response of the regenerated apical and intracanal tissues.

RESULTS

Signs of orthodontic-induced external root resorption were observed in 2 of the 4 presented cases without, however, the presence of any associated adverse events. No other complications were observed, either clinically or radiographically, throughout the observation period. In the long-term, all 4 cases responded favorably to orthodontic forces, maintaining healthy apical tissues and structural integrity of both intracanal as well as apically regenerated tissues.

CONCLUSIONS

The orthodontic movement of REP-treated teeth seems feasible, nevertheless, special care should be implemented. Lightly acting orthodontic forces, short duration of active movement, and close monitoring of the patient seem to be prerequisites to limit complications to a minimum and achieve a favorable healing of REP-treated teeth in the long-term following orthodontic treatment completion.

Orthodontic management of traumatic dental injuries in Norway and orthodontists' perceptions of referral routines: A quality assurance survey

BACKGROUND/AIM

Orthodontic treatment of patients with traumatic dental injuries is challenging, with limited evidence of routines and outcomes. The aims of this study were: (i) to describe how orthodontists perceive the information on traumatic dental injuries received by referral from the Public Dental Health Service before orthodontic treatment and (ii) to assess orthodontists' knowledge and working routines in managing traumatic dental injuries.

MATERIALS AND METHODS

Data were obtained through a survey of all practicing orthodontists registered as members of the Norwegian Association of Orthodontists (n = 203).

RESULTS

Eighty-three orthodontists were enrolled, most of whom had received their dental degree (73.0%) and specialist orthodontic training (88.5%) in Norway. They reported examining patients with a history of traumatic dental injury at weekly (34.2%) or monthly (38.0%) basis. In 85.5% of cases, they obtained a history of traumatic dental injury from patients. Half of the respondents (51.3%) favoured two-phase early orthodontic treatment for patients with an overjet ≥6 mm. The observation time and treatment strategy showed considerable discrepancies across traumatic dental injury diagnoses. Most (59.1%) orthodontists considered the information on previous traumatic dental injuries provided by the Public Dental Health Services referral 'inadequate', more commonly in cases of mild (83.5%) than severe (57.5%) traumatic dental injuries.

CONCLUSIONS

Orthodontic management of patients with traumatic dental injuries was characterised by lack of uniformity in both recommended observation time before orthodontic treatment and management strategy. The referral routines by the Public Dental Health Services for patients with traumatic dental injuries were perceived as 'inadequate' in terms of frequency and quality. The results indicate the requirement of standardisation of routines related to orthodontic management of traumatic dental injuries and referral routines by the Public Dental Health Services.

Do orthodontic movements of traumatized teeth induce dental pulp necrosis? A systematic review

INTRODUCTION

Usually, orthodontic movements encompass children and young adult patients, which are more susceptible to the occurrence of traumatic dental injuries. It is necessary to understand whether the effects of orthodontic movements on traumatized teeth could induce pulp necrosis. The aim of this study was to answer the following question: "Do orthodontic movements of traumatized teeth induce dental pulp necrosis?".

MATERIAL AND METHODS

Searches were performed for studies published up to May 11, 2023, in the MEDLINE/PubMed, Cochrane Library, Scopus, SciELO Citation Index, Web of Science, EMBASE, and Grey Literature Report databases, without restriction for language or year of publication. The revised Cochrane risk of bias tools for nonrandomized interventions (ROBINS-I) was used to assess the quality of the included studies. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool.

RESULTS

Of 2671 potentially relevant studies, five were included. Four were classified as having a moderate risk of bias and one as a serious risk of bias. It was reported a higher susceptibility to pulp necrosis in teeth subjected to orthodontic movements with history of trauma involving periodontal tissues. Additionally, orthodontic movements of traumatized teeth with total pulp obliteration had an increased risk of pulp necrosis. GRADE analysis presented a moderate certainty of evidence.

CONCLUSIONS

An increased risk for pulp necrosis when traumatized teeth are subjected to orthodontic movements was verified. However, this is based on evaluations performed with subjective tests. Further well-designed studies are necessary to confirm this trend.

CLINICAL RELEVANCE

Clinicians must be aware of the possibility of pulp necrosis. However, endodontic treatment is recommended when verified signs and symptoms of pulp necrosis.

Endodontic-orthodontic interactions: a review and treatment recommendations

The literature is replete with articles describing the many and varied interactions between endodontic treatment and orthodontic tooth movement (OTM), often reporting conflicting views and findings, which creates confusion for clinicians. Original research and review articles have described aspects such as apical root resorption and potential pulpal complications of teeth related to OTM. Some interactions are of relatively minor clinical significance, whilst others may have adverse consequences. A history of dental trauma before or during OTM further complicates the interactions. This review re-assesses the historical literature on endodontic-orthodontic interactions in light of more recent research and presents guidelines for managing clinical situations involving both disciplines. © 2023 Australian Dental Association.

Impact of Dental Trauma on Orthodontic Parameters-A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Investigation into the impact of dental trauma on the results of orthodontic treatment is crucial because it can have a major influence on patient care. However, there has not yet been a thorough review or meta-analysis of the available data, which is inconsistent and scant. Therefore, the goal of this systematic review and meta-analysis is to investigate the impact of dental trauma on orthodontic parameters. Search methods and criterion of selection: Major online databases were searched (beginning from the year 2011) for relevant articles using a properly defined search strategy. Analysis protocol: Risk of bias (RoB) and the Cochrane risk of bias tool were utilized for the purposes of bias evaluation within the individual studies and within the review, respectively.

RESULTS

Out of the six clinical trials selected, a significant impact of trauma was observed in individuals in all but one paper. Gender predilection varied across studies and could not be conclusively determined. The follow-up period ranged from two months to two years in the trials. The odds ratio (OR) 0.38 [0.19, 0.77] and the risk ratio (RR) 0.52 [0.32, 0.85] indicated that both the odds as well as the relative risk of experiencing dental trauma were lower in the group with negligible impact compared to the group with noticeable impact. Conclusion and further implications: The findings show that dental trauma significantly affects orthodontic parameters, with lower risk and likelihood of suffering dental trauma in the group with negligible impact than in the group with noticeable impact. However, given the substantial heterogeneity among the studies, it is advised to exercise caution when extrapolating the findings to all populations. Registration and protocol: Registration in the PROSPERO database was carried out before initiating the investigation [CRD42023407218].

Assessment of the Maximum Amount of Orthodontic Force for Dental Pulp and Apical Neuro-Vascular Bundle in Intact and Reduced Periodontium on Bicuspids (Part II)

This study examines 0.6 N-4.8 N as the maximum orthodontic force to be applied to dental pulp and apical NVB on intact and 1-8 mm reduced periodontal-ligament (PDL), in connection with movement and ischemic, necrotic and resorptive risk. In addition, it examines whether the Tresca finite-element-analysis (FEA) criterion is more adequate for the examination of dental pulp and its apical NVB. Eighty-one (nine patients, with nine models for each patient) anatomically correct models of the periodontium, with the second lower-premolar reconstructed with its apical NVB and dental pulp were assembled, based on X-ray CBCT (cone-beam-computed-tomography) examinations and subjected to 0.6 N, 1.2 N, 2.4 N and 4.8 N of intrusion, extrusion, translation, rotation, and tipping. The Tresca failure criterion was applied, and the shear stress was assessed. Forces of 0.6 N, 1.2 N, and 2.4 N had negligible effects on apical NVB and dental pulp up to 8 mm of periodontal breakdown. A force of 4.8 N was safely applied to apical NVB on the intact periodontium only. Rotation and tipping seemed to be the most invasive movements for the apical NVB. For the dental pulp, only the translation and rotation movements seemed to display a particular risk of ischemia, necrosis, and internal orthodontic-resorption for both coronal (0-8 mm of loss) and radicular pulp (4-8 mm of loss), despite the amount of stress being lower than the MHP. The Tresca failure criterion seems more suitable than other criteria for apical NVB and dental pulp.

Assessment of the Best FEA Failure Criteria (Part II): Investigation of the Biomechanical Behavior of Dental Pulp and Apical-Neuro-Vascular Bundle in Intact and Reduced Periodontium

The aim of this study was to biomechanically assess the behavior of apical neuro-vascular bundles (NVB) and dental pulp employing Tresca, Von Mises, Pressure, S1 and S3 failure criterions in a gradual periodontal breakdown under orthodontic movements. Additionally, it was to assess the accuracy of failure criteria, correlation with the maximum hydrostatic pressure (MHP), and the amount of force safe for reduced periodontium. Based on cone-beam computed tomography, 81 3D models of the second lower premolar were subjected to 0.5 N of intrusion, extrusion, rotation, tipping, and translation. A Finite Elements Analysis (FEA) was performed. In intact and reduced periodontium apical NVB, stress (predominant in all criteria) was significantly higher than dental pulp stress, but lower than MHP. VM and Tresca displayed identical results, with added pulpal stress in translation and rotation. S1, S3 and Pressure showed stress in the apical NVB area. 0.5 N seems safe up to 8 mm periodontal breakdown. A clear difference between failure criteria for dental pulp and apical NVB cannot be proved based only on the correlation quantitative results-MHP. Tresca and VM (adequate for ductile materials) showed equivalent results with the lowest amounts of stress. The employed failure criteria must be selected based on the type of material to be analyzed.

Insights Into Pulp Biomineralization in Human Teeth

Introduction

Mineralized pulp (MP) compromises tooth function and its causation is unknown. The hypothesis of this study is that pulp mineralization is associated with pulpal tissue adaptation, increased mineral densities, and decreased permeabilities of tubular dentin and cementum. Methods will include correlative spatial mapping of physicochemical and biochemical characteristics of pulp, and contextualize these properties within the dentin-pulp complex (DPC) to reveal the inherent vunerabilities of pulp.

Methods

Specimens (N = 25) were scanned using micro X-ray computed tomography (micro-XCT) to visualize MP and measure mineral density (MD). Elemental spatial maps of MP were acquired using synchrotron X-ray fluorescence microprobe (μXRF) and energy dispersive X-ray spectroscopy (EDX). Extracted pulp tissues were sectioned for immunolabelling and the sections were imaged using a light microscope. Microscale morphologies and nanoscale ultrastructures of MP were imaged using scanning electron (SEM) and scanning transmission electron microscopy (STEM) techniques.

Results

Heterogeneous distribution of MD from 200 to 2,200 mg/cc, and an average MD of 892 (±407) mg/cc were observed. Highly mineralized pulp with increased number of occluded tubules, reduced pore diameter in cementum, and decreased connectivity in lateral channels were observed. H&E, trichrome, and von Kossa staining showed lower cell and collagen densities, and mineralized regions in pulp. The biomolecules osteopontin (OPN), osteocalcin (OCN), osterix (OSX), and bone sialoprotein (BSP) were immunolocalized around PGP 9.5 positive neurovascular bundles in MP. SEM and STEM revealed a wide range of nano/micro particulates in dentin tubules and spherulitic mineral aggregates in the collagen with intrafibrillar mineral surrounding neurovascular bundles. EDX and μXRF showed elevated counts of Ca, P, Mg, and Zn inside pulp and at the dentin-pulp interface (DPI) in the DPC.

Conclusion

Colocalization of physical and chemical, and biomolecular compositions in MP suggest primary and secondary biomineralization pathways in pulp and dentin at a tissue level, and altered fluid dynamics at an organ level. Elevated counts of Zn at the mineralizing front in MP indicated its role in pulp biomineralization. These observations underpin the inherent mechano- and chemo-responsiveness of the neurovascular DPC and help elucidate the clinical subtleties related to pulpitis, dentin-bridge, and pulp stone formation.

Primary tooth autotransplantation: update and retrospective clinical study

OBJECTIVE

A new technique of primary tooth autotransplantation has recently been published demonstrating reliable replacement of missing permanent incisors in young children due to trauma or agenesis. This retrospective clinical study reports on the longterm success of this new technique in a larger patient group regarding its potential to support bone and soft tissue growth.

STUDY DESIGN

40 children (age range: 2.7-17.6 years) received 53 primary tooth autotransplants (49 canines and 4 incisors) due to traumatic tooth loss (73%), agenesis (19%) or dysplasia/displacement (8%). Clinical and radiological follow-up examinations were performed to check up on root resorption, bone and soft tissue growth, survival and success.

RESULTS

22 transplants still present in the oral cavity of 18 patients yielded a success rate of 77%. The Kaplan-Meier estimator measured a median survival time of 86 months (7.2 years) for all 53 grafts. In all cases, increasing soft tissue and bone development enabled a successful prosthetic rehabilitation regarding aesthetics and function.

CONCLUSIONS

Primary tooth autotransplantation reliably restores edentulous anterior space in children experiencing traumatic tooth loss or agenesis and acts as an immediate therapy before other therapies such as premolar transplantation or orthodontic space closure can be carried out at a later time. It guarantees the co-development of soft tissue and bone in the teenage jaw which is associated with high patient satisfaction and acceptance of this method.

Do orthodontic tooth movements induce pulp necrosis? A systematic review

BACKGROUND

Orthodontic tooth movements are performed by applying forces on teeth, which may cause alterations within the dental pulp. Previously published systematic reviews on the subject only included a small number of studies that assessed pulp status through reliable diagnostic methods. Since then, new evidence has been published, and a further systematic review on the subject is necessary.

OBJECTIVES

To evaluate whether there is scientific evidence to support the possibility that orthodontic tooth movements could induce pulp necrosis.

METHODS

A systematic search of articles published until June 2020 was performed using MeSH and free terms in the PubMed, Cochrane Library, LILACS, SciELO, Web of Science, EMBASE, Open Grey and Grey Literature databases. Randomized clinical trials (RCTs), nonrandomized clinical trials (nRCTs) and longitudinal (prospective or retrospective) studies that evaluated the pulp status of teeth subjected to orthodontic movements using laser Doppler flowmetry or pulse oximetry were included. The revised Cochrane risk of bias tools for randomized trials (RoB 2) and nonrandomized interventions (ROBINS-I) were used to assess the quality of the included studies. Relevant findings were summarized and evaluated. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool.

RESULTS

Initial screening of databases resulted in 353 studies. In total, 285 studies were excluded because they were duplicates. Of 68 eligible papers, fourteen met the inclusion criteria and were selected for full-text reading. Two studies were excluded due to the methods used to evaluate pulp status. Twelve studies (five RCTs, one nRCT and six prospective) were included. Four RCTs were classified as having an unclear risk of bias and one as having a high risk of bias. The nRCT was classified as having a low risk of bias. Two prospective studies were classified as having a moderate risk of bias and four as having a serious risk of bias. The GRADE analysis demonstrated a low to very low quality of evidence.

DISCUSSION

Significant limitations regarding the randomization processes within the included RCTs and a lack of control of confounders on most nonrandomized and longitudinal studies were verified.

CONCLUSIONS

This systematic review indicates that orthodontic movements do not induce loss of pulp vitality with low to very low certainty of evidence.

Use of Orthodontic Methods in the Treatment of Dental Luxations: A Scoping Review

(1) Background: Treating dental luxation injuries is challenging for the clinician. Dental luxations account for 18-33% of injuries to permanent teeth and can be addressed using different therapeutic approaches. The present work was conducted with two aims: (i) to evaluate, through a scoping review, current knowledge of the orthodontic methods (repositioning and stabilization splinting) that can be used at the time of the trauma, and (ii) to investigate the frequency and type of pulp consequences arising after these traumatic injuries. (2) Methods: The literature search was conducted in the period June 2020-December 2020 using the PubMed/MEDLINE, SCOPUS and Web of Science databases. The research questions were formulated according to the PICO (Population, Intervention, Comparison, Outcomes) method and considered the following aspects: type of luxation injury and stage of root development; use of orthodontic repositioning and splinting techniques; frequency and type of pulp consequences; and compliance of treatments with international guidelines. (3) Results: The initial screening of the databases, using the selected search keywords, yielded a total of 587 articles, just 8 fully met the inclusion criteria. Closer analysis of these 8 publications revealed that they would not produce clear meta-analytical data. This made it necessary to limit the data collected to the following six items: number and type of injuries, initial therapeutic intervention, duration of follow-up, number, and type of different pulp consequences. (4) Conclusions: While orthodontic techniques are commonly used to treat dental intrusions, in the case of extrusive and lateral luxation injuries, they are less frequently used and the orthodontic approach is generally confined to the stabilization phase. Among the various possible pulp consequences, many authors consider only pulp canal obliteration (PCO) and pulp necrosis (PN), often tending to overlook physiological healing (pulp survival) and the possible development of PN after PCO. There is therefore a clear need for new, high-quality clinical studies of this topic based on systematic and standardized data collection.

Extrusive Luxation Injuries in Young Patients: A Retrospective Study with 5-Year Follow-Up

(1) Background: The purpose of this study was to analyze the influence of the chosen diagnostic and therapeutic approach (repositioning and splinting methods) on the risk, frequency and timing of the onset of pulp canal obliteration and pulp necrosis following extrusive luxation in young patients with permanent dentition. (2) Methods: From an initial sample of 50 subjects affected by extrusive luxation, were selected the clinical data of 13 patients presenting extrusive luxation but no other type of injury to the dental hard tissue. All teeth were examined according to a standardized protocol. Follow-up examinations were performed at regular intervals for 5 years. Statistical associations between pulp consequences and several covariates were assessed using the Mann-Whitney test and Fisher's exact test. (3) Results: Among the 13 studied teeth, only 1 healed completely, whereas 9 showed pulp obliteration and 3 developed pulp necrosis. No tooth with obliteration developed pulp necrosis. The average time to treatment was 11.9 h. The treatment approaches used were manual repositioning, orthodontic repositioning and stabilization splinting. "Time to treatment" was the only covariate that showed a weak statistical association with the onset of pulp consequences. (4) Conclusions: There is still uncertainty over the most appropriate therapeutic approach to adopt in young patients with extrusive luxation injuries, particularly for repositioning of the injured tooth. Extruded teeth should be treated as soon as possible after the traumatic event. This study highlighted the value of orthodontic repositioning of the extruded tooth, which does not seem to aggravate the conditions of the dental pulp. In addition, the study confirmed that prophylactic endodontic treatment is not appropriate for immature teeth affected by extrusive luxation injuries, given the extreme rarity of pulp necrosis in teeth already affected by pulp obliteration.

Orthodontic treatment recommendation and expected adverse reactions in patients with a history of dental trauma: A survey among general dentists, paediatric dentists, and orthodontic specialists

BACKGROUND

Trauma-induced adverse reactions may trigger complications when moving teeth orthodontically.

AIM

The purpose of this study was to evaluate the knowledge of dental practitioners about this topic.

DESIGN

A questionnaire survey was organized among general dentists, paediatric dentists, and orthodontists in Flanders (Belgium). Three clinical cases describing trauma-induced tooth damage (tooth ankylosis, apical root resorption, and pulp/root canal obliteration) were presented, followed by a set of questions.

RESULTS

The questionnaire was completed by 121 general dentists (GD), 47 paediatric dentists (PD), and 99 orthodontic specialists (OS). In the case with ankylosis, impossibility to move the tooth orthodontically was reported as most frequent adverse reaction (82.8% of GD, 95.7% of PD, and 100.0% of OS) (P < .001). In the situation of apical root resorption, the most frequently reported adverse event was progressive apical root resorption (78.9%, 85.7%, and 88.8% respectively; P = .265). Most frequently mentioned adverse reaction in the case with pulp and root canal obliteration was tooth discoloration (64.1%, 57.1%, and 78.3%; P = .055), followed by apical root resorption (57.4%, 56.8%, and 68.7%; P = .283). Orthodontic treatment recommendation differed among specific clinical situations but also among groups of dental practitioners.

CONCLUSIONS

Important knowledge gaps exist regarding the orthodontic managment of traumatized teeth. This topic requires more attention in undergraduate training, specialist training, and continuing education.

Knowledge of orthodontic treatment approach of traumatized teeth by a group of Belgian general dentists, pediatric dentists, and orthodontists

BACKGROUND/AIM

Traumatized teeth are more susceptible to complications during orthodontic tooth movement. The aim of this study was to explore current practices among Belgian dental practitioners regarding orthodontic treatment of children with a history of dental trauma.

MATERIAL AND METHODS

A questionnaire survey was organized among general dentists, pediatric dentists, and orthodontists in Flanders (Belgium). Questionnaires were distributed at the occasions of annual meetings or symposia. They consisted of questions regarding exposure to dental trauma and orthodontic treatment approach for patients with a dental trauma history.

RESULTS

The questionnaire was completed by 121 general dentists, 47 pediatric dentists, and 99 orthodontists. A history of dental trauma influenced referral for orthodontic treatment by general dentists and pediatric dentists moderately (median VAS scores of 5 and 6, respectively, on a scale of 0 (not at all) to 10 (utmost)), indicating uncertainty and doubt. Additional checkups during tooth movement were usually not organized by general dentists in 33.6% and by pediatric dentists in 19.1% of cases (P = 0.006). One-third of the orthodontists (33.3%) experienced tooth loss linked to orthodontic movement of a tooth with dental trauma history in at least one patient. Only a minority of the practitioners knew of the existence of specific guidelines (7.6%, 15.6% and 22.7%, respectively, of general dentists, pediatric dentists, and orthodontists) (P = 0.007). The Dental Trauma Guide was the guideline mentioned most frequently, although this tool does not contain recommendations regarding orthodontic treatment after trauma.

CONCLUSION

In the group of Belgian general dental, pediatric and orthodontists surveyed, there was uncertainty regarding the orthodontic management of patients with a history of dental trauma especially among general practitioners. Further educational training is recommended.

Valid consent and orthodontic treatment

Valid patient consent is a legal and ethical principle that is fundamental to healthcare provision. Oral health practitioners (OHPs) must understand the principles that need to be addressed to ensure that the consent given by a patient is valid. Failure to obtain consent may result in a negligence claim or a complaint of professional misconduct against the OHP. Orthodontic treatment is mostly elective but is not without risk to the patient. Obtaining and maintaining valid consent for orthodontic treatment presents additional challenges in comparison with other dental procedures as the treatment lasts over a longer time and is most commonly performed in adolescents. In addition, prospective patients need to be informed regarding ‘lifelong’ management in the retention phase to minimise the risk of relapse. The present paper outlines the principles of valid consent with particular regard to orthodontic treatment in the adolescent patient. OHPs must ensure that they are satisfied that the competent patient has the capacity to voluntarily consent. Clinicians must also recognise that valid consent is not a one-off ‘tick the box’ procedural exercise but an ongoing process of effective information sharing in light of changing laws and an ever-changing scientific evidence base within a patient-centred model of healthcare.

Bleaching of a Discolored Tooth with Retrieval of Remnants after Successful Regenerative Endodontics

INTRODUCTION

This report presents the retrieval of remnants from a discolored mandibular right second premolar (tooth #29) of a 17-year-old female after a successful regenerative endodontic procedure (REP).

METHODS

The REP was performed in October 2011. Coronal discoloration became of great concern to the patient at a review visit in 2016. A cone-beam computed tomographic scan was taken to investigate the formation of hard tissues within the root canal as well as a region of no calcified tissue formation. During internal bleaching of tooth #29, a black material with particulate inclusions was retrieved and examined histopathologically.

RESULTS

Five years after the REP, there was complete periapical healing, hard tissue formation within the root canal, and complete maturation of the root apex. A hard tissue bridge was noted at the cementoenamel junction when the pulp chamber of #29 was reaccessed. The remnants retrieved from the pulp chamber were confirmed to be partly mineral trioxide aggregate (MTA). A normal tooth color was achieved after 3 weeks of internal bleaching.

CONCLUSIONS

MTA remnants within the pulp chamber contributed to the tooth discoloration and appear to have obstructed hard tissue formation. A matrix of oxidized regenerated cellulose seems not to hinder tissue regeneration and is resorbed by these tissues. Other materials with color stability should be selected as coronal barriers for REPs to avoid a potential adverse effect of the MTA on the REP outcome and discoloration.

Potential risks of orthodontic therapy: a critical review and conceptual framework

This review examines some of the potential risks of orthodontic therapy along with their evidence base. The risks of orthodontic treatment include periodontal damage, pain, root resorption, tooth devitalization, temporomandibular disorder, caries, speech problems and enamel damage. These risks can be understood to arise from a synergy between treatment and patient factors. In general terms, treatment factors that can influence risk include appliance type, force vectors and duration of treatment whilst relevant patient factors are both biological and behavioural. Hence, the natural variation between orthodontic treatment plans and patients gives rise to variations in risk. A good understanding of these risks is required for clinicians to obtain informed consent before starting treatment as well as to reduce the potential for harm during treatment. After considering each of these risks, a conceptual framework is presented to help clinicians better understand how orthodontic risks arise and may therefore be mitigated.

Hyperlipidemia induced by high-fat diet enhances dentin formation and delays dentin mineralization in mouse incisor

Dyslipidemia has become a serious health problem in children and adolescents worldwide for its high prevalence. Since hard tissues of permanent teeth form mainly during this period and lipids are actively involved in tooth development, the effects of hyperlipidemia on dental tissue formation and mineralization need to be illustrated. In this study, hyperlipidemia model was established in mice fed with high-fat diet (HFD). Micro-CT and histomorphological analyses were performed on the mandibular bones to assess the morphological changes of the mandibular incisor and first molar. After 4 weeks of HFD feeding, mice had significantly elevated serum lipid levels compared with mice fed with control diet. After 8 weeks, the mandibular incisor presented significantly increased dentin thickness and decreased diameter of pulp cavity in HFD-fed mice compared with control diet-fed mice, while its gross morphology and enamel thickness were not altered. In the mandibular first molar, dentin thickness of root did not show difference between the two groups. Histological section showed that mandibular incisor of HFD-fed mice manifested a wider predentin region and a lower mineral apposition rate compared with that of the control mice. In conclusion, hyperlipidemia induced by HFD feeding enhances dentin formation and delays dentin mineralization in the developing mouse incisor.

Influence of orthodontic forces on human dental pulp: a systematic review

AIM

The aim of the present study was to systematically review the influence of orthodontic force on human dental pulp.

METHODS AND RESULTS

The addressed focused question was "Do orthodontic forces affect the human dental pulp?" which was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a specific question was constructed according to the PICO (Participants, Interventions, Control, Outcomes) principle. Databases were explored from 1952 up to and including August 2014 using different combinations of the following keywords: "orthodontic force"; "dental pulp"; "reaction" and "tooth movement". Literature reviews, letters to the editor, commentaries and case-reports were excluded. Thirty studies were included. Six studies assessed the effect of orthodontic forces on pulpal blood flow and 20 studies investigated the pulpal cellular responses to orthodontic forces. In 4 studies, pulpal responses to orthodontic forces were compared between previously traumatized- and non-traumatized teeth.

CONCLUSIONS

There is insufficient scientific validation regarding the association between orthodontic forces and human dental pulp. However, a history of dental trauma maybe considered a risk factor for loss of pulp vitality during orthodontic treatment.

Autotransplantation and surgical uprighting of impacted or retained teeth: A retrospective clinical study and evaluation of patient satisfaction

OBJECTIVES

This retrospective clinical study aimed to determine the success rate of autotransplanted impacted or retained teeth along with a patient satisfaction survey and to analyze the influence of relevant clinical and radiographic parameters.

SUBJECTS AND METHODS

Fifty-seven teeth (37 canines, 10 molars, seven premolars, three incisors) in 45 patients (median 15 years) were evaluated over a mean of 1.6 years. The success criteria were pocket probing depth ≤3.5 mm, mobility grade ≤ II, Periotest ≤30 and complete alveolar bone healing. The influencing parameters were oral hygiene, smoking, periodontal screening index, occlusal/proximal contacts, horizontal position, dental age, pulp obliteration and degree of displacement. Furthermore, bone height was measured.

RESULTS

The overall success rate was 74%, along with a high patient satisfaction. The survival rate was 96% after a mean follow-up of 1.6 years. The favorable factors were proper oral hygiene, non-smoking, good general periodontal condition, proximal contacts and pulp obliteration. An increase in or maintenance of bone level was found in 96%.

CONCLUSIONS

Autotransplantation of impacted or retained teeth is an appropriate treatment, if orthodontic alignment has failed, especially in growing patients.

Radicular maturity level of primary teeth and its association with trauma sequelae

AIM

This study aimed to investigate the influence of the radicular maturity level of primary teeth on the sequelae of traumatic dental injury (TDI).

MATERIALS AND METHODS

A longitudinal retrospective study that collected data from dental records and radiographs of patients with TDI in one or both maxillary primary central incisors was conducted. Sequelae such as crown discoloration, pulp canal obliteration (PCO) and inflammatory root resorption (IRR) were evaluated during a 12- to 18-month follow-up period after the trauma.

RESULTS

Of the 132 patients included in the study, 103 (78%) had luxations and 29 (22%) had dental fractures. At the initial postinjury examination, 12 teeth (9.1%) were found to have immature roots, 107 (81.1%) had closed apexes and 13 (9.8%) had visible root resorption. Inflammatory root resorption occurred mostly in traumatized teeth that presented with physiological root resorption at the moment of trauma (P = 0.004). The frequency of PCO was higher in teeth with a closed apex at the moment of the injury (P = 0.026). There was also an association between the type of injury and the occurrence of crown discoloration (P = 0.008) as well as between the type of injury and the development of PCO (P = 0.001).

CONCLUSIONS

The occurrence of TDI sequelae can be determined by the type of injury as well as by the radicular maturity level of the primary teeth at the moment of injury.

Marfan syndrome: a review of the literature and case report

Marfan syndrome (MFS) is a connective tissue disorder of variable inheritance that affects multiple organ systems. Cardiovascular, ocular, and skeletal abnormalities are cardinal features of the syndrome. Orofacially, MFS patients typically exhibit skeletal class II malocclusion, dolichofacial growth pattern, mandibular retrognathia, malar hypoplasia, high arched palate, dental crowding, and root anomalies. The purpose of this paper is to provide a review of the literature, as well as describe an 11-year-old female with MFS diagnosed at the age of 10.5 years. This report emphasizes the orofacial findings in MFS and highlights particularities of dental treatment when social deficits and intellectual disabilities are also implicated.

Pulp canal obliteration: an endodontic diagnosis and treatment challenge

AIM

To review the literature on pulp chamber and root canal obliteration in anterior teeth and to establish a clear protocol for managing teeth with fine, tortuous canal systems.

SUMMARY

Pulp canal obliteration (PCO) occurs commonly following traumatic injuries to teeth. Approximately 4-24% of traumatized teeth develop varying degrees of pulpal obliteration that is characterized by the apparent loss of the pulp space radiographically and a yellow discoloration of the clinical crown. These teeth provide an endodontic treatment challenge; the critical management decision being whether to treat these teeth endodontically immediately upon detection of the pulpal obliteration or to wait until symptoms or signs of pulp and or periapical disease occur. The inevitable lack of responses to normal sensibility tests and the crown discoloration add uncertainty to the management; however, only approximately 7-27% of teeth with PCO will develop pulp necrosis with radiographic signs of periapical disease. Root canal treatment of teeth with pulpal obliteration is often challenging. This article discusses the various management approaches and highlights treatment strategies for overcoming potential complications.

KEY LEARNING POINTS

Up to 25% of traumatized anterior teeth can develop pulp canal obliteration; Discolouration is a common clinical finding in teeth with pulp canal obliteration; Up to 75% of teeth with pulp canal obliterations are symptom-free and require no treatment other than radiographic monitoring; Routine pulp sensibility tests are unreliable in the presence of pulp canal obliteration; Teeth with pulp canal obliteration in need of root canal treatment pose particular diagnostic and treatment challenges.

Evaluation of radiographs, clinical signs and symptoms associated with pulp canal obliteration: an aid to treatment decision

Pulp canal obliteration (PCO) is a sequela of tooth trauma. The dental clinician faced with this condition has to make a difficult decision. The aim of this study was to evaluate the clinical signs and symptoms associated with teeth with PCO and to assess the status of the periapical tissues using the periapical index (PAI) as an aid in making a treatment decision. The study included teeth diagnosed with PCO in patients with a history of traumatic injury to the involved teeth. Histories of associated signs and symptoms including pain, swelling and drainage from a sinus tract were elicited. Tooth color, sensibility to electric pulp testing, mobility and percussion tenderness were recorded. The periapical status was assessed using the PAI. Two hundred and seventy-six teeth were diagnosed with PCO. One hundred and fifty-seven (56.9%) and 119 (43.1%) demonstrated partial or total PCO, respectively. Yellow discoloration presented most frequently, occurring in 186 (67.4%) teeth. Sixty-two (33.3%) of these had developed periapical lesions and reacted negatively to sensibility testing. Fifty-seven (30.7%) of these teeth presented radiographically with a normal periapical appearance and reacted normally to sensibility testing, whereas 67 (36.0%) presented with small changes in the periapical bone pattern and reacted in the high normal range to sensibility testing. Teeth with PAI scores < or =2 presented with occasional spontaneous pain. Teeth with PAI scores > or =3 presented with clinical symptoms and signs ranging from pain on percussion to spontaneous pain, and slight swelling to sinus tract drainage. Based on the findings of this study, endodontic treatment should be initiated in teeth with tenderness to percussion, PAI scores > or =3 and a negative response to sensibility testing.