Pulp Canal Research Articles

Clinical outcome of guided endodontics versus freehand drilling: A controlled clinical trial, single arm with external control group.

High-quality, prospective clinical studies are needed to increase evidence for guided endodontics. This study aims to assess the clinical outcome of guided endodontics for treatment of teeth presenting with pulp canal obliteration (PCO) in comparison with freehand treatment. This trial was registered in the ISRCTN.com registry (ISRCTN75277265) and designed as a controlled clinical trial: Single arm trial, prospective, nonrandomized, single-centre study (ethical approval number S64630). Inclusion criteria were; tooth presenting with PCO and symptoms and/or signs of apical periodontitis (AP). An external control group was selected from clinical records of patients presenting the same criteria but treated freehanded. Guided root canal treatments were performed by the same operator on all patients. Freehanded treatments were performed by a specialist in endodontics under microscope with pre-operative CBCT available. Primary outcome for both groups was evaluated as: canal found, canal not found, or perforation. As secondary outcome, the qualitative accuracy of the drill path was assessed as: optimal precision, acceptable precision or technical failure. Patients were followed up yearly. Descriptive statistics on the study patient's demographics and healing outcome were performed and specific statistical analysis was performed on each outcome variable. A total of 133 teeth were included (n = 60 guided, n = 73 freehanded) from 128 patients (n = 59 guided, n = 69 freehanded). The primary outcome for the guided group was: 59 teeth canals found and 1 tooth canal not found. No perforations were recorded. In the freehanded group, the root canal was successfully found in 59 teeth, seven were not found, and seven had a perforation. An analysis of all data showed that guided endodontics presented statistically significant better outcome than freehand treatment (p < .05). Guided endodontics showed a statistically significant better outcome than freehanded treatment resulting in less technical failures. However, it is a complex procedure which should be carried out by an experienced endodontist with the aid of a dental microscope.

Potential for pulp revascularization in mature anterior teeth with lateral luxation in relation to the patient's age at the time of injury-a retrospective cohort study.

The aim of this study was to investigate the potential for pulp revascularization in relation to patient age at the time of injury following luxation injury of mature anterior permanent teeth. A total of 93 teeth from 70 patients were included. The patients were divided into subgroups based on their age at the time of the injury. the Aalen-Johansen method was used to estimate the risks of pulp canal obliteration (PCO) and pulp necrosis (PN). The absolute 2year risks of PCO and PN were obtained with cause-specific Cox regression and reported separately for each cohort, standardised to age at injury and degree of repositioning. For the group younger than 15years of age, the risk of PN after 12months was 62.3% [95% CI 44.9; 79.7] in the cohort from 1972 to 1980 and 28.6% [95% CI 4.9; 52.2] in the cohort from 2012 to 2020. For the age group 16-20 years, the risk of PN after 12 months was 66.7 [95% CI 40.0;93.3] in the cohort from 1972 to 1980 and 25% [95% CI 0.0;55.0] in the cohort from 2012 to 2020. For the age group between 21 and 25, the risk of PN after 12months was 66.7% [95% CI 40.0; 93.3] in the cohort from 1972 to 1980 and 55.6% [95% CI 23.1; 88.0] in the cohort from 2012 to 2020. There is potential for pulp revascularization in mature anterior teeth with lateral luxation in patients up to 25 years of age. The risk of PN appears to increase with age.

Penetration of Intracoronal Bleaching Agents Across a Calcium Silicate-Based Coronal Barrier in Pulpless Immature Permanent Teeth: An In Vitro Study.

Tooth bleaching procedures on nonvital teeth have been performed for crown discoloration caused by regenerative endodontic therapy (RET). However, leakage of bleaching agents across the root canal can be detrimental. This study aimed to assess and compare the penetration levels of hydrogen peroxide (HP) from different bleaching agents across calcium silicate-based coronal barriers in immature permanent teeth. Fifty extracted single-rooted human teeth were randomly divided into four groups (n = 10): Group I (HH)-35% hydrogen peroxide (HP); Group II (SS)-a mixture of sodium perborate (SP) powder and saline; Group III (SH)-a mixture of SP powder and 30% HP liquid; Group IV (CP)-10% carbamide peroxide gel. The control group (Group V, CC) was treated with distilled water. The bleaching agent was replaced on the 4th day, and penetration analysis was performed on the 7th day using ferro thiocyanate (FTC) method and a UV-spectrophotometer at a wavelength of 480 nm. Compared with the control group, the SH group (SP mixed with HP) showed a significant difference, indicating substantial HP penetration across the root canal space (p value < 0.0001). Intergroup comparisons also revealed a significant difference between the SS and SH groups (p value < 0.0001), suggesting that the SS group had less penetration. Compared with other bleaching agents, SP mixed with saline/water resulted in the lowest HP penetration in the pulp canals of the RET-simulated tooth models. This study is the first to investigate HP penetration from different bleaching agents in teeth that have undergone RET, identifying the safest bleaching agent for use in these cases. This study also provides a foundation for further research to develop precise guidelines for nonvital tooth bleaching protocols in RET-treated teeth.

Precision in endodontic therapy by novel-guided approach

Abstract Guided endodontics has proven effective in treating pulp canal obliteration (PCO). However, challenges arise when dealing with limited vertical space, particularly in cases where long burs and guides are necessary. In this case report, we introduce a novel approach utilizing a sleeveless three-dimensional (3D)-printed guide, aimed at overcoming vertical space constraints while maintaining visibility and irrigation during drilling. A 22-year-old male patient presented with intermittent pain around tooth #21, diagnosed with pulp necrosis and symptomatic apical periodontitis. Employing the sleeveless 3D-printed guide alongside a long neck carbide bur, we achieved a minimally invasive access cavity up to the root canal. This technique presents a promising alternative to conventional guided endodontic approaches, particularly beneficial in cases of PCO.

Cone-Beam Computed Tomographic Scan–based Assessment of the Correlation between the Location of Caries and Pulp Canal Obliteration: An Aid to Treatment Planning

IntroductionThis study aimed to determine the correlation between proximal caries and the extent and site of pulp canal obliteration (PCO) in cone-beam computed tomographic (CBCT) scans of mandibular molar teeth. MethodsA total of 1491 CBCT scans of patients 18–49 years of age were selected from the database (2002–2022). From them, 328 teeth with proximal caries and satisfying inclusion criteria were evaluated by 2 calibrated evaluators. PCO was observed in the sagittal and coronal planes. PCO and proximal caries were compared concerning different age groups, sexes, and sites using an independent sample t test. ResultsThe prevalence of PCO among patients with proximal caries is 47%. In mesial proximal caries, the extent of PCO is significantly greater in the distal root canal (73.4%), whereas in distal proximal caries, PCO is more often found in the mesial canal (77.3%). The mean extent of intraradicular calcification was higher in the distal canal (P < .001). Moreover, mesial proximal caries showed a greater extent of intraradicular obliteration (P < .001). The probability of developing PCO was significantly higher in females (P = .003). ConclusionsWithin the limitations of this study, it can be concluded that the extent of calcification is more common on the opposite side of the location of the proximal caries. Moreover, such intraradicular calcification is greater in a distal canal compared to a mesial canal. Sex plays a significant role in the calcification process, showing higher predilection in females compared to males.

Risk of Healing Complications Following Alveolar Process Fractures in the Primary Dentition: A Retrospective Clinical Cohort Study.

Alveolar bone process fractures in preschool children are not well documented in the literature. Alveolar process fractures are located very close to primary teeth and permanent tooth germs. This study investigates the risk of healing complications following alveolar process fractures in the primary dentition and potential sequelae in the permanent dentition. A retrospective cohort study was conducted involving 21 patients with 49 primary teeth involved in an alveolar fracture. The follow-up protocol included clinical and radiographic examinations at specified intervals up to the age of 6 years. Healing complications in the primary teeth such as pulp necrosis, pulp canal obliteration, ankylosis, infection-related resorption and premature tooth loss were examined. Sequelae in the permanent dentition was also registered when the permanent incisors had erupted. Over a 3-year follow-up, the incidence of premature tooth loss was 51.2% [95% CI: 34.1%-68.4%], pulp canal obliteration was 42.5% [95% CI: 27.1%-57.8%], and pulp necrosis was 8.9% [95% CI: 0.6%-17.3%] following an alveolar process fracture. No cases of ankylosis were observed. Sequelae in the permanent dentition primarily included demarcated opacities and hypoplasia with a risk estimated at 24% [95% CI: 13%-39%] and 9% [95% CI: 2%-21%] respectively. Alveolar process fractures in primary dentition are associated with several healing complications in the primary teeth. Although the likelihood of severe complications in the permanent dentition is low, young children are still susceptible to developing sequelae in their permanent teeth. These results highlight the importance of awareness of dental injuries following alveolar process bone fractures in the primary dentition.

Static Guided Approach for Obliterated Canal -A Case Report of Maxillary Central Incisor

In recent decades, significant technological advances have deeply influenced our daily lives. Notably, innovations such as 3D printers and 3D cone-beam computed tomography have become valuable tools in clinical dentistry. Diagnosing and treating teeth with pulp canal obliteration presents unique challenge in endodontic procedures. These challenges include the risk of breaking root canal instruments during treatment, preparing overly extended access cavities, and misaligning the access cavity, which could potentially lead to root perforation. Recently, guided endodontics has gained popularity as a method to address these issues. This case report explores the use of guided endodontics in treating a maxillary central incisor with pulp canal obliteration. This approach is advantageous as it reduces the time patients spend undergoing treatment and, more critically, minimizes the risk of inadvertent damage to the tooth structure.

Microtomographic and histological evaluation of two bioceramics as pulp capping agents in vivo.

Maintaining pulp vitality and function is a priority of the medicaments employed in pulp therapy to preserve tooth integrity. Aim: This study evaluated inflammatory response and reparative dentin bridge formation after direct pulp capping with two different bioceramics. Materials and Method: This was an in vivo controlled experimental study on 12 male Wistar rats. Pulpotomies were performed and the exposed pulps were capped with Biodentine or Neo MTA. After 15, 45 and 90 days, maxillary segments were obtained and prepared for histologic analysis and Micro-CT. Hounsfield Units (HU) were quantified. Results: Micro-CT analysis showed greater mineralization at 90 days with Neo MTA than with Biodentine. HU did not differ significantly (p >0.05) between molars treated with Biodentine and Neo MTA at 15 and 45 days, but at 90 days, there was statistically significant difference (p <0.05) between them. Reparative dentin was observed near the pulp exposure and canal orifice with both bioceramics. At 45 and 90 days, molars treated with Neo MTA showed mineralized tissue filling the canal orifice. Molars treated with Biodentine showed mineralized tissue and dentin bridge at the site of exposure at 45 days, and total pulp exposure coverage and mineralized entin matrix at 90 days. Conclusions: Biodentine and Neo MTA induce the formation of reparative dentin bridge after 45 days with inflammatory cell infiltrate.

Visualization of Pulpal Structures by SWIR in Endodontic Access Preparation.

Endodontic access preparation is one of the initial steps in root canal treatments and can be hindered by the obliteration of pulp canals and formation of tertiary dentin. Until now, methods for direct intraoperative visualization of the 3-dimensional anatomy of teeth have been missing. Here, we evaluate the use of shortwave infrared radiation (SWIR) for navigation during stepwise access preparation. Nine teeth (3 anteriors, 3 premolars, and 3 molars) were explanted en bloc with intact periodontium including alveolar bone and mucosa from the upper or lower jaw of human body donors. Analysis was performed at baseline as well as at preparation depths of 5 mm, 7 mm, and 9 mm, respectively. For reflection, SWIR was used at a wavelength of 1,550 nm from the occlusal direction, whereas for transillumination, SWIR was passed through each sample at the marginal gingiva from the buccal as well as oral side at a wavelength of 1,300 nm. Pulpal structures could be identified as darker areas approximately 2 mm before reaching the pulp chamber using SWIR transillumination, although they were indistinguishable under normal circumstances. Furcation areas in molars appeared with higher intensity than areas with canals. The location of pulpal structures was confirmed by superimposition of segmented micro-computed tomography (µCT) images. By radiomic analysis, significant differences between pulpal and parapulpal areas could be detected in image features. With hierarchical cluster analysis, both segments could be confirmed and associated with specific clusters. The local thickness of µCTs was calculated and correlated with SWIR transillumination images, by which a linear dependency of thickness and intensity could be demonstrated. Lastly, by in silico simulations of light propagation, dentin tubules were shown to be a crucial factor for understanding the visibility of the pulp. In conclusion, SWIR transillumination may allow direct clinical live navigation during endodontic access preparation.

LESION STERILISATION AND TISSUE REPAIR OF PRIMARY TEETH

BACKGROUND Lesion sterilization and tissue repair is also known as non-instrumental endodontic therapy. It involves the use of combination of antibiotics drugs on infected pulp tissue and root canals after getting access to the root canal orifices of the primary teeth. Various combination of antibiotics had been used by some dentists with macrogol , polyethylene glycol, propylene glycol, normal saline or sterile water as the solvent or vehicle used. METHODS An electronic literature search in Science direct and Google was done in December, 2023 using the Population, Concept and Context framework. Search terms and keywords were combined by Boolean operators. Two independent investigators screened titles and abstracts of publications on lesion sterilization and tissue repair of primary teeth. Original research articles, case report, case series with accessible full text were included for review, while review articles, systematic reviews, viewpoints, books, letters, thesis, editorials, book chapters, dissertations and perspectives were among articles excluded during screening. RESULTS One case report was identified from Morocco, a case series from Nigeria and randomized controlled trial from Egypt respectively. CONCLUSIONS Lesion sterilization and tissue repair or non-instrumental endodontic therapy can be a treatment option for primary teeth with infected pulp and root canals .More studies from diverse ethnic population in Africa countries will fill the gaps in knowledge and add to the existing literature.

Dentistry In Metaverse - Virtual Aspect Of Practical World

Modern advancements in dentistry have provided great ease in the dental practice. Dentophobia is a major concern especially during the time of invasive dental procedures. Virtual Reality (VR) and Augmented Reality (AR) have proven beneficial in changing the patient’s experience as well as in providing a thorough exposure of the clinical application of dentistry to the dental professionals hence improving their skills and quality of education. VR and AR have set their foot in almost every single branch of dentistry, ranging from maxillofacial surgery, implantology, endodontics to pediatric dentistry. AR and VR are the perfect example of amalgamation of the virtual world and the real world. There are three types of VR systems- immersive, semi-immersive and non-immersive. With the AR system a surgeon is able to map the entire surgery along with the necessary modifications to be incorporated during the procedure to increase its efficacy. VR and AR systems are the modern non pharmacological methods used in the behaviour management in pediatric dentistry with significant positive results. These systems are also used in detecting the pulp canals which increases the quality of an RCT. The use of AR and VR has improved the diagnosis leading to the formulation of an effective and upgraded treatment plan. However certain disadvantages like visual fatigue, expenditure and equipment failure cannot be overlooked while utilising these revolutionised systems.

Tooth Autotransplantation, Autogenous Dentin Graft, and Growth Factors Application: A Method for Preserving the Alveolar Ridge in Cases of Severe Infraocclusion-A Case Report and Literature Review.

Background: Tooth infraocclusion is a process in which a completely or partially erupted tooth gradually moves away from the occlusal plane. Submerged teeth can lead to serious complications. Treating teeth with infraocclusion is very challenging. One of the procedures allowing for the replacement of a missing tooth is autotransplantation. The aim of this paper is to review the literature on teeth autotransplantation, supported by a case report involving the autotransplantation of a third mandibular molar into the site of an extracted infraoccluded first mandibular molar, as well as the utilization of advanced platelet-rich fibrin (A-PRF) alongside autogenous dentin grafts for bone tissue regeneration. Methods: A severely infraoccluded first permanent right mandibular molar was extracted and then ground to obtain the dentin graft. A-PRF clots (collected from the patient's peripheral blood) were added to the autogenous dentin graft, to create the A-PRF membrane. An atraumatic extraction of the lower left third molar was performed and then it was transplanted into the socket of tooth no. 46. Immediately after transplantation, tooth no. 38 was stabilized with orthodontic bracket splints for 3 months. The patient attended regular follow-up visits within 12 months. Results: After one year, the patient did not report any pain. In the clinical examination, the tooth and surrounding tissues did not show any signs of infection. However, radiographically, cervical inflammatory resorption, unchanged pulp canal dimensions, absent root growth, periapical radiolucency, and lack of apical and marginal healing were observed. Reconstruction of the bone defect was obtained and the alveolar ridge of the mandible was preserved. Due to poor stability of the tooth and severe resorption, the tooth needed to be extracted. Conclusions: This study is designed to critically evaluate the efficacy of autotransplantation, the application of growth factors, and the integration of autogenous dentin grafts in remedying dental deficiencies resulting from reinclusion. We aim to point out the possible causes of treatment failure.

Comparative evaluation of the clinical and radiographic success of regenerative endodontic procedures in immature versus mature permanent incisors with apical periodontitis: A prospective observational study

ABSTRACT Aim: The aim of the study was to know the clinical and radiographic outcomes of regenerative endodontic procedures of immature versus mature in young permanent incisors with apical periodontitis. Methods: Twenty non-vital, young permanent incisors with traumatic exposure between the age of 7 and 13 years were taken. Patients were divided into two groups: Group I – immature (number of teeth included = 10) and Group II – mature (number of teeth included = 10). The procedure was performed by the blood clot method as a scaffold. Biodentine (about 2–3 mm) was placed as a capping material at the cementoenamel junction. Evaluation was based on the clinical (pain, sinus, tender on percussion, swelling, mobility, intact restoration) and radiographical (Nolla stage, thickening of walls, lamina dura continuity, calcification of pulp chamber and canal, periapical healing, PAI score) parameters. Results: All 19 teeth were clinically asymptomatic after the 12-month follow-up. Radiographically, the percentage of continuous root development (in the immature group) was 100% at 12 months (P = 0.000**). Radiography revealed a reduction in the PAI scores at 12 months in the immature and mature groups. None of the treated teeth responded to the cold test after a 12-month follow-up. One patient did not come for intervention in the mature group. All the statistical tests (Chi-square, Mann–Whitney U-test, and Fisher’s exact test) were performed at a 5% significance level. Conclusion: Outcomes did not differ significantly between immature and mature groups.

Long-term complications and management of dental trauma in the adult patient - Part 1: fractured teeth, pulpal complications and resorption.

Dental trauma is one of the most common injuries encountered in the younger population. This can have a long-term impact on the patient's overall quality of life as they may have to deal with the sequelae of these injuries for years to come. Young boys experience dental trauma more frequently than young girls and one of the most common outcomes of these injuries are fractured teeth. This first paper in a two-part review series aims to provide an overview of dental trauma followed by a discussion on management of fractured teeth, associated pulpal complications and resorption. These can be uncomplicated fractures involving enamel and/or dentine, or complicated fractures involving enamel, dentine and pulp. They can involve the crown, the crown and root together, or present solely as root fractures. Pulpal complications can lead to pulp necrosis or pulp canal obliteration. Resorption can be internal or external, inflammatory, or replacement type. The management of each of these injuries begins with a thorough assessment followed by initiating emergency treatment to stabilise the presenting condition. This is followed by a long-term treatment plan which aims to address the patients' aesthetic and functional requirements and provide the patient with the most suitable treatment outcome in the hope to improve their sense of wellbeing and overall quality of life.

Optimal outcomes of pulpotomy in young patients: Long-term prospects for permanent molars with signs and symptoms indicative of irreversible pulpitis

ObjectivesLimited literature addresses the long-term success of complete pulpotomy in permanent molars with signs of irreversible pulpitis in young patients. The aim of this observational study was to prospectively evaluate the long-term outcomes of complete pulpotomy using mineral trioxide aggregate (MTA) over an average period exceeding 11 years. MethodsOut of 27 molars displaying signs suggestive of irreversible pulpitis which underwent MTA pulpotomy, 24 molars were followed-up for a mean duration of 11.0 ± 2.2 years (range 8.2 to 14.8 years). Clinical and radiographic assessments were periodically conducted, tailored to each patient's specific circumstances. Treatment failure criteria included clinical signs and symptoms and radiographic evidence suggesting a lack of pulpal or periapical healing. Results83 % of molars had signs and symptoms of symptomatic irreversible pulpitis, with 83 % displaying apical periodontitis. Clinically and radiographically, all pulpotomies (100 %) were considered successful. A hard tissue barrier was observed in 71 % of teeth, and continued root maturation was evident in all molars with open apices. Complete pulp canal obliteration (PCO) was present in 21 % of the molars. All radiographic apical radiolucencies completely resolved. ConclusionsThis study demonstrates a 100 % success rate over an average 11-year follow-up for complete pulpotomy in managing permanent molars with signs and symptoms of irreversible pulpitis in young patients. It offers evidence for its long-term efficacy in promoting healing of pulp and periapical tissues. Clinical significanceThis study showed high long-term success for complete pulpotomy in young permanent molars with irreversible pulpitis, with clinical and radiographic success over 11 years. Despite initial symptoms of pulpitis and apical periodontitis, the treatment resulted in tissue healing, root maturation, and resolution of periapical radiolucencies, suggesting it as an alternative to root canal therapy.

A Computed Tomographic Study of the Molar Teeth of Babyrousa spp.

A photographic and computed tomography (CT) scanning study was carried out on 295 molar teeth of 18 adult male Babyrousa babyrussa skulls and 8 skulls of Babyrousa celebensis including seven adult males and one adult female. The occlusal morphology of the permanent maxillary and mandibular molar teeth of B. babyrussa was very similar to that of B. celebensis. Most B. babyrussa maxillary molar teeth had six roots, with small numbers of teeth having four, five or seven roots. A similar pattern was suggested in B. celebensis. Mandibular molar teeth had between four and eight roots. Tooth roots of maxillary and mandibular first and second molar teeth were largely tapering, rod-like structures. The roots of the right and left maxillary third molar teeth had a more complex arrangement; some were inserted almost vertically into the maxilla; others were orientated in a more distal direction. The mesial and distal roots were splayed in appearance. The right and left mandibular third molar tooth roots retained elements of the open 'C' shape and were generally orientated distally. The pulp chambers were arched to fit under the main cusps in all molar teeth. Pulp canals were variable in number.

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.

Regenerative Endodontic Procedures in Immature Teeth Affected by Regional Odontodysplasia

IntroductionRegional odontodysplasia (ROD) is a rare developmental disorder characterized by hypo-mineralization and hypoplasia of enamel and dentin. Symptoms include poorly developed tooth buds, delayed eruption of permanent teeth in affected quadrants, and ghost teeth. The affected teeth often become necrotic due to abnormal enamel and dentin development, making them susceptible to caries and infection. The aim of this case report is to describe the treatment of ROD through pulp revascularization. Case reportA 13-year-old girl was referred for endodontic treatment. The mandibular left incisors and first premolar, which were affected by regional odontodysplasia, lost their vitality because of the impaired structure of the enamel. Due to the teeth's early developmental stage, a regenerative endodontic treatment was attempted. All 3 teeth were treated using the same protocol following the AAE guidelines. After 4 weeks, treatment of the premolar was completed, whereas the incisor teeth remained symptomatic and were and therefore, intracanal dressing with calcium hydroxide was repeated and left in place for 5 months. Finally, the regenerative procedure was completed, and the crowns were restored. The patient was scheduled for follow-up examinations after 6 months, and then yearly for the next 3 years. After 1 year, the periapical lesion around the central incisor and premolar had resolved, the lesion around the apex of the lateral incisor was healing, and the roots had continued to develop. After 3 years, complete healing and pulp canal obliteration were observed in the central incisor and in the premolar. However, the root of the lateral incisor tooth was split, and it was recommended to extract this tooth. ConclusionThe positive outcomes of regenerative endodontics in the central incisor and premolar suggest that revascularization of the pulp may be optional for the treatment of immature necrotic teeth affected by developmental disorders, such as ROD, amelogenesis imperfecta, or dentinogenesis imperfecta.

A retrospective cohort study of pulp prognosis in luxated permanent teeth: a competing risk analysis.

The present retrospective cohort study aimed to evaluate luxated permanent teeth for pulp prognosis and risk factors. Case records and radiographs of 224 patients, involving 427 luxated permanent teeth, referred for treatment at the Dental Trauma Center-School of Dentistry, Universidade Federal de Minas Gerais, (DTC-SD-UFMG) from 2014 to 2022, were assessed for pulp prognosis classified as vitality, necrosis and pulp canal obliteration (PCO). A competing risk survival analysis estimated the hazards of the three outcomes, and the effect of demographic, clinical and treatment variables was tested using a cause specific Cox regression model. Pulp vitality was found in163 teeth (38.2%), pulp necrosis in 120 teeth (28.1%) and 55 teeth (12.9%) developed PCO. Pulp vitality decreased in the presence of concomitant crown fractures (HR 0.38 95% CI [0.2-0.8] p = 0.006). The risk of pulp necrosis (HR 0.62 95% CI [0.4-0.96] p = 0.03) was lower in cases with open apices but increased with concomitant crown fractures (HR 4.0 95% CI [2.6-6.1] p = 0.001) and intrusions (HR 2.3 95% CI [1.2-4.1] p = 0.007). Lateral or extrusive luxations (HR 3.0 95% CI [1.3-6.9] p = 0.001) and open apices (HR 2.4 95% CI [1.2-4.7] p = 0.01) showed higher rates of PCO. Type of luxation, the diameter of the apical foramen, and the presence of concomitant crown fractures were main determinants of pulp prognosis after luxation injuries in permanent teeth. Pulp prognosis after tooth luxation is dependent on the presence and direction of tooth displacement together with infection control. Not applicable.

Comparison between three methods of diode laser 810 nm, photodynamic therapy with laser 660 nm, and hypochlorite solution for disinfection of pulp canal of primary teeth

Background: The presence of treatment-resistant microorganisms is known as the main cause of pulpectomy failure in the endodontic treatment of deciduous teeth. The usage of lasers can contribute to reducing these microorganisms. This study aimed to compare the effect of three disinfection methods for deciduous teeth canals using laser diode 810 nm, photodynamic therapy with laser 660 nm and methylene blue, and sodium hypochlorite. Materials and Methods: In this experimental study, 58 single-root deciduous teeth with no root resorption were investigated in four groups, including one control group of 10 and three intervention groups of 16. Preparation of the samples was done using manual files up to three numbers after the initial file. After sterilizing the samples in an autoclave, Enterococcus faecalis bacteria were cultured in the canals. In the first group, irrigating with hypochlorite 2.5% was done; in the second group, photodynamic therapy was performed using a laser diode and 0.1 mg/mL methylene solution; and in the third group, high-intensity laser 810 nm direct radiation was done into the canal. Next, samples were taken from all canals. The colony formation unit (CFU) of the bacteria was counted in the blood agar culture medium. The data were analyzed using Kruskal-Wallis and negative binomial regression test (α =0.05). Results: The mean CFU differed significantly between the four groups. The rate of incidence of E. faecalis colonies showed a reduction in all three intervention groups compared to the negative control. In the high-intensity laser 810 nm group, there was 68.4%; in the photodynamic therapy with diode 660 nm and methylene blue, there was 88%; and in the hypochlorite group, 98.3% reduction was observed compared to the negative control group. Conclusion: Based on the results of this study, to compare three disinfection methods of the deciduous teeth canals without preparation of canals, sodium hypochlorite had greater efficiency. All three groups of laser, photodynamic therapy, and sodium hypochlorite showed reductions of E. faecalis bacterial colony compared to the control group. The reductive effects of CFU were greater in the hypochlorite sodium group, followed by photodynamic and direct laser radiation groups.