Micro-computed Tomography Assessment of Dentinal Micro-cracks after Root Canal Preparation with TRUShape and Self-adjusting File Systems.

INTRODUCTION: The aim of the present study was to evaluate the percentage frequency of dentinal micro-cracks observed after root canal preparation with TRUShape and Self-Adjusting File (SAF) systems by means of micro-computed tomography imaging analysis. A conventional full-sequence rotary system (BioRace) and a single-file reciprocation system (Reciproc) were used as reference techniques for comparison because of their known assertive cutting efficiency. METHODS: Forty anatomically matched mandibular incisors were selected, scanned at a resolution of 14.25 µm, and assigned to 4 experimental groups (n = 10), according to the preparation protocol: TRUShape, SAF, BioRace, and Reciproc systems. After the experimental procedures, the specimens were scanned again, and the registered preoperative and postoperative cross-section images of the roots (n = 70,030) were screened to identify the presence of dentinal micro-cracks. RESULTS: Overall, dentinal defects were observed in 28,790 cross-section images (41.11%). In the TRUShape, SAF, BioRace, and Reciproc groups, dentinal micro-cracks were visualized in 56.47% (n = 9842), 42.38% (n = 7450), 32.90% (n = 5826), and 32.77% (n = 5672) of the slices, respectively. All dentinal defects observed in the postoperative data sets were already present in the corresponding preoperative images. CONCLUSIONS: None of the preparation systems induced the formation of new dentinal micro-cracks.

Micro-CT assessment of dentinal micro-cracks after root canal filling procedures.

AIM: To evaluate the frequency of dentinal micro-cracks after root canal filling procedures with GuttaCore (GC), cold lateral compaction (CLC) and warm vertical compaction (WVC) techniques in mandibular molars using micro-computed tomographic analysis. METHODOLOGY: Thirty mesial roots of mandibular molars, with a type II Vertucci's canal configuration, were prepared to working length with a Reciproc R40 instrument and randomly assigned to one of the three experimental groups (n = 10), according to the technique used for root filling: GC, CLC or WVC. The GC group was filled with a size 40 GC obturator, whilst CLC and WVC groups used conventional gutta-percha cones. AH Plus sealer was used in all groups. The specimens were scanned at an isotropic resolution of 14.25 µm before and after root canal preparation and after root filling. Then, all pre- and postoperative cross-sectional images of the roots (n = 41 660) were screened to identify the presence of dentinal defects. RESULTS: Overall, 30.75% (n = 12 810) of the pre- + post-filling images displayed dentinal defects. In the GC, CLC and WVC groups, dentinal micro-cracks were observed in 18.68% (n = 2510), 15.99% (n = 2389) and 11.34% (n = 1506) of the cross-sectional images, respectively. All micro-cracks identified in the post-filling scans were also observed in the corresponding post-preparation images. CONCLUSION: Root fillings in all techniques did not induce the development of new dentinal micro-cracks.

Micro-computed Tomographic Assessment on the Effect of ProTaper Next and Twisted File Adaptive Systems on Dentinal Cracks.

INTRODUCTION: The aim of the present study was to evaluate the frequency of dentinal microcracks observed after root canal preparation with ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland) and Twisted File Adaptive (TFA; SybronEndo, Orange, CA) systems through micro-computed tomographic analysis. METHODS: Twenty moderately curved mesial roots of mandibular molars presenting a type II Vertucci canal configuration were randomly assigned to 2 experimental groups (n = 10) according to the system used for the root canal preparation: PTN or TFA systems. The specimens were scanned through high-resolution micro-computed tomographic imaging before and after root canal preparation. Afterward, pre- and postoperative cross-sectional images of the mesial roots (N = 25,820) were screened to identify the presence of dentinal defects. RESULTS: Dentinal microcracks were observed in 38.72% (n = 5150) and 30.27% (n = 3790) of the cross-sectional images in the PTN and TFA groups, respectively. All dentinal defects identified in the postoperative scans were already present in the corresponding preoperative images. CONCLUSIONS: Root canal preparation with PTN and TFA systems did not induce the formation of new dentinal microcracks.

Assessment of dentinal damage during canal preparation using reciprocating and rotary files.

INTRODUCTION: The role of motion kinematics in creating dentinal damage during instrumentation is not very clear. The purpose of this study was to compare the formation of dentinal cracks with instruments working in continuous rotation and reciprocating motion. METHODS: One hundred twenty extracted human mandibular premolars were selected for the study. Thirty teeth served as controls, and the remaining 90 teeth were divided into 3 groups depending on the root canal preparation technique. Group 1 samples were treated with WaveOne primary files (Dentsply Maillefer, Ballaigues, Switzerland), group 2 samples with single F2 ProTaper (Dentsply Maillefer) working in reciprocating motion, and group 3 samples were prepared with sequential ProTaper (Dentsply Maillefer) until F2 working in continuous rotation motion. Roots were then sectioned at 3, 6, and 9 mm from the apex, and the cut surface was observed under a stereomicroscope for the presence of dentinal microcracks. RESULTS: The control group and WaveOne, single F2 ProTaper in reciprocating motion, and continuous ProTaper groups caused cracks in 0%, 15%, 26%, and 53% of samples, respectively. A statistically significant difference was found between 2 reciprocating file groups (WaveOne and single F2 ProTaper in reciprocating motion) and the continuous rotation group (ProTaper) (P < .05). However, no significant difference was found among the 2 reciprocating file groups (P > .05). CONCLUSIONS: Dentinal cracks are produced irrespective of motion kinematics. Within the limits of this study and the current literature, such incidence is less with instruments working in reciprocating motion compared with those working in continuous rotation.

Traumatic dental injury among 12-year-old South Brazilian schoolchildren: prevalence, severity, and risk indicators.

An increasing prevalence of traumatic dental injury (TDI) has been reported in the last few decades. The aim of this study was to assess the prevalence and severity of TDI and its association with socio-demographics and physical characteristics in the anterior permanent teeth of 12-year-old Brazilian schoolchildren. A cross-sectional study was carried out in a population-based sample of 1528 subjects attending 33 public and nine private schools (response rate of 83.17%). A single calibrated examiner performed the clinical examinations at the schools and recorded the TDI index (Children's Dental Health Survey criteria), overjet and lip coverage. Height and weight were measured to calculate the body mass index (BMI). Parents/legal guardians answered a questionnaire containing socio-demographic questions. The relationships among TDI, socio-demographic variables and physical characteristics were assessed by survey Poisson regression models. The prevalence of TDI was 34.79% (mild trauma = 24.37%; severe trauma = 10.43%). Male schoolchildren (RR = 1.41, 95% CI = 1.23-1.61, P = 0.002) and schoolchildren from low socioeconomic status (RR = 1.32, 95% CI = 1.07-1.64, P = 0.021) were more likely to present at least one tooth with TDI, whereas students attending 7th grade (advanced students) were less likely to experience TDI (RR = 0.59, 95% CI = 0.43-0.82, P = 0.012). Regarding the severity analysis, students of mid-high (RR = 1.46, 95% CI = 1.09-1.94, P = 0.022), mid-low (RR = 1.68, 95% CI = 1.01-2.77, P = 0.045) and low (RR = 1.78, 95% CI = 1.11-2.85, P = 0.027) socioeconomic status were more likely to have mild trauma when compared with schoolchildren of high socioeconomic status. No significant association between severe trauma and socioeconomic status was observed. In conclusion, this study showed a high prevalence of TDI in 12-year-old Brazilian schoolchildren. Socio-demographic data and school achievement were associated with TDI.

Traumatic dental injury with treatment needs negatively affects the quality of life of Brazilian schoolchildren.

BACKGROUND: Traumatic dental injury (TDI) has been considered a significant problem in youth, not only because of its consequences to the craniofacial structures but also for its potential impact on the quality of life of affected individuals. AIM: The aim of this study was to investigate the impact of TDI with treatment needs on the oral health-related quality of life (OHRQoL) of South Brazilian schoolchildren. DESIGN: A cross-sectional study was performed in Porto Alegre, Brazil, using a multistage probability sampling strategy. Of 1837 eligible 12-year-old schoolchildren attending public and private schools, 1528 were examined. OHRQoL was assessed by the Brazilian version of the Child Perceptions Questionnaire for 11-to 14-year-old children (CPQ11-14) - 16-item short form. Clinical examination was conducted to assess the presence of TDI in permanent incisors (Children's Dental Health Survey criteria), malocclusion, and dental caries. Parents/legal guardians answered questions on socioeconomic status. Statistical analyses were performed using Poisson regression models. RESULTS: The overall CPQ11-14 score was not associated with TDI. In the functional limitations domain, individuals presenting TDIs with treatment needs experienced significantly higher mean CPQ11-14 than individuals with no TDI or without treatment needs (RR = 1.21; 95% CI = 1.05-1.39), after adjusting for malocclusion, dental caries, gender, and socioeconomic status. No other domains were associated with TDI. CONCLUSIONS: This study revealed that TDI with treatment needs negatively affects the OHRQoL in this population of 12-year-old schoolchildren and that this impact is related to oral functions.

Incisor trauma in a Turkish preschool population: prevalence and socio-economic risk factors.

OBJECTIVE: This study aimed to assess the prevalence of traumatic injuries of the primary incisors in preschool children from 2 to 5 years old in South-Eastern Anatolia, Turkey. Additionally, the relationship between traumatic dental injuries, parents' education level, family income, size of incisal overjet and the presence of anterior open bite were examined. BASIC RESEARCH DESIGN: A cross-sectional survey CLINICAL SETTINGS: Data were collected through oral examinations and structured interviews, and included socio-economic indicators. PARTICIPANTS: A total of 727 children of both genders were included in the study. 122 of these children were aged 2; 183 aged 3; 178 aged 4 and 186 aged 5. RESULTS: The prevalence of dental injuries was 8.0% (n = 58). The highest frequency of trauma in the primary teeth was observed at the age of 4. Boys experienced more dental injuries than girls, 12.2% and 4.0%, respectively. The most common crown fracture was in enamel only (57%) followed by crown fracture of enamel and dentin (19%). CONCLUSION: The prevalence of dental injuries in Turkish preschool children was very low. The children with incisal overjet greater than 5mm and anterior open bite experienced more dental injuries in primary teeth than their counterparts with normal occlusion. Socio-economic indicators were not statistically significantly associated with the occurrence of traumatic dental injuries.

Mineral trioxide aggregate pulpotomies: a case series outcomes assessment.

BACKGROUND: The greatest threats to developing teeth are dental caries and traumatic injury. A primary goal of all restorative treatment is to maintain pulp vitality so that normal root development or apexogenesis can occur. If pulpal exposure occurs, then a pulpotomy procedure aims to preserve pulp vitality to allow for normal root development. Historically, calcium hydroxide has been the material of choice for pulpotomy procedures. Recently, an alternative material called mineral trioxide aggregate (MTA) has demonstrated the ability to induce hard-tissue formation in pulpal tissue. The authors describe the clinical and radiographic outcome of a series of cases involving the use of MTA in pulpotomy procedures. METHODS: Twenty-three cases in 18 patients were treated with MTA pulpotomy procedures in an endodontic private practice. All of the patients had been referred to the practice for diagnosis and treatment of a symptomatic tooth. All of the authors provided treatment. Pulpal exposures were either due to caries or complicated enamel dentin fractures. RESULTS: Nineteen teeth in 14 patients were available for recall. The mean time of recall was 19.7 months. Of the 19 cases, 15 involved healed teeth, and three involved teeth that were healing. One of 19 cases involved a tooth with persistent disease. CONCLUSIONS: MTA may be useful as a substitute for calcium hydroxide in pulpotomy procedures. Further research, however, is required to clarify this conclusion. CLINICAL IMPLICATIONS: MTA conceivably could replace calcium hydroxide as the material of choice for pulpotomy procedures, if future research continues to show promising results.

Avaliação do risco de cárie - uma revisão da literatura / Evaluation of dental caries risk - literature review

O processo de carie caracteriza-se por ser uma condição patológica de origem infecciosa e caráter multifatorial que acomete os componentes minerais dos dentes. A compreensão do processo carioso levou à introdução de medidas preventivas, com isso, a busca de instrumentos de predição tornou-se um fator de extrema importância dentro da Odontologia. A proposta deste trabalho é revisar alguns métodos de predição de cárie.

Traumatic injuries to permanent anterior teeth among 12-year-old schoolchildren in Jordan.

OBJECTIVES: To assess the prevalence and related factors of incisor trauma among 12-year-old Jordanian schoolchildren. DESIGN: Cross-sectional study among schoolchildren. A sample of 1.878 schoolchildren aged 12 years, 940 boys and 938 girls, were randomly selected from 128 schools in urban and rural areas. Ellis classification was used to record the dental injuries on incisors. RESULTS: Of the children examined 13.8% showed dental trauma. Difference in prevalence between boys (17.1%) and girls (10.6%) was statistically significant (p < 0.05). Maxillary central incisors were the most affected (79.2%) and the most common type of crown injury was enamel-dentin fracture (40.6%). The relationship between dental injuries and socio-economic indicators was not statistically significant. There was a tendency for children with an incisal overjet greater than 5.0 mm to have experienced dental injuries (p < 0.01). Treatment need due to dental injuries was very high but less than untreated damage. CONCLUSION: The prevalence of traumatic injuries to permanent incisors in 12-year-old Jordanian schoolchildren was close to that found in other countries. Being a boy and having overjet greater than 5.0 mm were significant predisposing factors to dental injuries.

Incisor trauma and early treatment for Class II Division 1 malocclusion.

This study investigated incisor trauma in children with overjets greater than or equal to 7 mm who were enrolled in a clinical trial of 2-phase early orthodontic treatment for Class II malocclusion. In phase 1, children were randomly assigned to treatment in the mixed dentition with either modified bionator or combination headgear or to a group in which treatment was delayed until the permanent dentition. All children received comprehensive treatment during phase 2 if necessary. At the start of the trial, 29.1% of the patients had already had some incisor trauma. This was not significantly related to dental developmental age. During the trial, there was an increase in trauma in all 3 groups, but the magnitude of this increase was not significantly greater in the group for which treatment was delayed until the permanent dentition. This might suggest that orthodontic intervention aimed at reducing trauma should begin very soon after the eruption of the maxillary incisors. However, the injuries tended to be minor, and the expected cost of treatment related to incisor trauma was small compared with the expected additional cost of a 2-phase orthodontic intervention.

Socio-economic correlates of traumatic injuries to the permanent incisors in schoolchildren aged 12 years in Blumenau, Brazil.

This study aimed to assess the prevalence of injuries to the permanent incisors in Blumenau, Brazil. In addition, the relationship between dental injuries and socio-economic indicators was examined. A cross-sectional survey was carried out. It included a random sample of 652 children aged 12 years, from both sexes, attending public and private primary schools in Blumenau, Brazil. Multi-stage sampling technique and proportional representation were adopted. A trained and calibrated dentist collected the data through clinical examinations and interviews. Clinical examination included type of damage, treatment provided and needed, size of incisal overjet and type of lip coverage. The response rate was 82.5%. The prevalence of dental injuries was 58.6%. Boys experienced more injuries than girls, 67.2% and 50.2% (P=0.001), respectively. Children from mothers with higher schooling experienced more dental injuries than those from of mothers with lower schooling, 68.2% and 56.6% (P=0.03). Father's level of education, parents' employment status and family income were not statistically significantly associated with dental injuries (P>0.05). There was a tendency for children with incisal overjet greater than 5 mm (P=0.2) and inadequate lip coverage (P=0.1) to have more dental injuries, but differences were not statistically significant. Nearly all (97.3%) children who had dental injuries needed treatment. In conclusion, the prevalence of dental injuries in Blumenau, Brazil, was very high, treatment of dental injuries was severely neglected, and boys and children from mothers with high schooling were more likely to have experienced dental injuries.

Prevalence of teeth with untreated dental trauma among nursery and primary school pupils in Dar es Salaam, Tanzania.

The aim of this study was to investigate the prevalence of teeth with untreated dental trauma among children aged 4-15 years in Dar es Salaam, Tanzania. A sample of 4524 children from three districts of different socio-economic status in the Dar es Salaam area was examined for signs of dental trauma in 1998/99. In 21% of all children examined, at least one type of untreated dental trauma was observed. A high percentage of untreated dental trauma was observed at the ages of 4 and 15 years. The most frequently observed type of dental trauma was enamel fracture (67%) followed by enamel-dentin fracture (26%). A significant gender influence on the occurrence of untreated dental trauma was observed, with more boys (23%) having untreated dental trauma than girls (19%). A higher percentage of untreated dental traumas was observed among children in the district with highest SES (26%) compared to the prevalence in the other two districts (14-17%). The findings of this study show that dental traumas are prevalent among Tanzanian children. Therefore, provision of information to the lay community about the importance of early management of dental trauma, ways of preventing trauma and appropriate handling of avulsed teeth is essential in order to minimize the rate of dental injuries and the related complications.

Social deprivation and traumatic dental injuries among 14-year-old schoolchildren in Newham, London.

AIMS: To assess the epidemiology of dental injuries among schoolchildren in Newham, London. MATERIAL AND METHODS: This study was carried out as part of the annual Community Dental Service's School Dental Inspection (SDI) programme in Newham. All schoolchildren aged 14 years were invited to participate in the study. Dental examinations were carried out by one trained examiner (SM) and included presence of clinical evidence of dental injuries, treatment provided and needed in the upper and lower permanent incisors, size of incisal overjet and type of lip coverage. The postcode was recorded to assess the levels of social deprivation. FINDINGS: 2242 out of 2684 children were examined. The prevalence of dental injuries was 23.7%. Treatment of dental injuries was neglected. Being male, having an incisal overjet greater than 5 mm and living in an overcrowded household increased the risk of having dental injuries. CONCLUSIONS: The prevalence of dental injuries in Newham (23.7%), which is a deprived area of London, was much higher than the overall prevalence in the UK (17%). Traumatic dental injuries seem to be a serious dental public health problem among children in deprived areas. Thus, there is an urgent need to collect local data on dental injuries in order to obtain a more comprehensive picture of the dental health.

An in vitro assessment of the dentine lost during instrumentation using the Periosonic system.

This study investigated the ability of a new instrument designed for root debridement, the Periosonic, to remove dentine compared to a hand curette and an ultrasonic scaler. The Periosonic system is a modification of the Micro-Megax endodontic system and uses modified files to remove plaque, calculus and tooth substance. The Periosonic has 2 file types; the Periosonic 1 is a more aggressive file for the removal of gross supra- and subgingival deposits, while the Periosonic 2 is a thinner more flexible file used for the removal of subgingival deposits. 40 human dentine specimens were ground flat and baseline measurements were made using a surfometer. The specimens were divided into 4 experimental groups and each group was treated with a hand curette, ultrasonic scaler, Periosonic 1 or 2 using 12, 1-s strokes. The specimens were remeasured blind in the surfometer. The curette removed 23.6 microm of dentine, the ultrasonic 6.8 microm, the Periosonic 1 18.8 microm and the Periosonic 2 12.5 microm. A qualitative assessment of the samples following mechanical preparation was also made. In conclusion, the Periosonic instrument does not remove more tooth substance than a conventional curette and may be a useful addition for the debridement of root surfaces.