Erosive Tooth Wear, Wine Intake, and Genetic Variation in COMT and MMP2.

INTRODUCTION: Erosive tooth wear (ETW) is a multifactorial condition of increasing prevalence in the younger population. This study aimed to explore the association between different ETW phenotypes with MMP2 and COMT single-nucleotide variants and selected environmental factors. METHODS: Saliva samples, erosive wear, and dental caries experience data and dietary/behavioral information from 16- to 18-year-old patients (n = 747) were used. Genotypes were obtained, and phenotypes were further analyzed considering diet and behavioral data, using logistic regression as implemented in PLINK, with an alpha of 0.05. RESULTS: When comparing individuals' ETW-free with those with mild ETW, an association was found with COMT rs6269 (p = 0.02). The comparison between ETW-free individuals with individuals with severe ETW also showed an association with COMT rs6269 under the recessive model (p = 0.03). Logistic regression showed that in the presence of less common alleles of MMP2 rs9923304 and COMT rs6269, ETW was more likely to occur when individuals drank wine. The GG genotype of COMT rs6269 was associated with the presence of lower (p = 0.02) and higher (p = 0.02) caries experience when individuals with ETW only in enamel were compared with individuals with ETW involving dentin. CONCLUSION: The results support a role of genes in ETW, with wine consumption being identified as a significant modulator, suggesting that gene-environment interactions may contribute to the development of ETW.

Evaluation of the cytotoxicity of new formulations of cariostatic agents containing nano silver fluoride: an in vitro study.

The objective of the study was to assess the indirect cytotoxicity of 600 ppm and 1500 ppm nano silver fluoride (NSF) compared to other commercial cariostatic agents. 56 dentin discs with 0.4 mm in thickness were obtained from intact human molars and adapted to artificial pulp chambers (APCs). The discs were divided into seven groups according to treatment (n = 8): no treatment (positive control-PC), 29% hydrogen peroxide (negative control-NC), 30% Cariestop (CS30), 38% Riva Star (RS38), 38% Advantage Arrest (AA38), 600 ppm NSF (NSF600), and 1500 ppm NSF (NSF1500). The cariostatic agents were applied on the occlusal surface of the dentin discs (facing upward), and the pulp surface (facing downward) remained in contact with the culture medium. Immediately after the treatments, the extracts (DMEM + cariostatic agent components diffused through the discs) were collected and applied to MDPC-23 cells, which were assessed for viability (CV-alamarBlue, live/dead), adhesion/spreading (F-actin), alkaline phosphatase (ALP) activity, and mineralization nodule (MN) formation. The data were statistically analyzed by ANOVA/Games-Howell (p = 0.05). CV and ALP activity in CS30, RS38, AA38, and NSF600 were similar to PC (p > 0.05). MN formation significantly decreased only in NC, CS30, RS38, and AA38 compared to PC (p < 0.001). Only NSF600 and NSF1500 did not differ from PC (p > 0.05) with mineralization nodules, and this specific cell activity significantly decreased in all other groups (p < 0.05). NSF solutions (600 ppm and 1500 ppm) did not cause transdentinal toxicity on MDPC-23 cells.

Bone age and dental late effects in childhood cancer survivors: Radiographic findings in a Brazilian sample.

BACKGROUND: Changes in bone age and tooth development are late side effects of cancer therapy and can be identified by imaging examination. AIM: To evaluate the late effects of antineoplastic treatment on bone age and dental development in childhood cancer survivors. DESIGN: This is a retrospective case-control study on paediatric cancer survivors of both sexes who underwent antineoplastic treatment with 5-15 years of survival. Carpal radiographs were assessed for bone age and growth curve, and panoramic radiographs were used to evaluate dental development and alterations. Carpal radiographs were analyzed using the Greulich and Pyle inspection method, and the Martins and Sakima method was used to analyze the growth curve. All tests were applied with a confidence level of 95%. RESULTS: The study and control groups comprised 28 and 56 patients, respectively. There was no significant difference in bone age and growth curve between the study and control groups. Nonetheless, when sex was compared to chronological and bone ages, there was a significant difference in bone age (p = 0.019) and an underestimation in both groups and sexes in the Greulich and Pyle method. As to late dental effects, dental agenesia, microdontia, gyroversion, and unerupted teeth were found. Dental shape alterations mainly involve the root region. CONCLUSION: Close multidisciplinary collaboration is necessary during the follow-up period of young patients who have survived cancer.

Evaluation of the genotoxic effects of formocresol application in vital pulp therapy of primary teeth: a clinical study and meta-analysis.

OBJECTIVES: This in vivo research investigated whether pulp treatments using formocresol for 7 days would cause mutagenic changes in children's lymphocytes. MATERIALS AND METHODS: The mutagenicity was tested in lymphocyte cultures established from the peripheral blood of children living in Brazil. The samples consisted of 2000 cells from teeth undergoing formocresol pulpotomies in which the formocresol pellet was sealed in the primary tooth for 7 days. It was removed on the seventh day, the base was placed, and the tooth was restored. Two venous blood samples (6-8 ml) were collected from each child; the first was prior to pulp therapy, and the second was 7 days later. Two thousand metaphases were analyzed. The level of significance adopted for the statistics was P < 0.05, and a random effects meta-analysis was performed combining this and two previous studies. RESULTS: There was no significant difference found in the metaphase analysis between the blood samples taken before and after the pulpotomy treatment (Wilcoxon signed rank test); however, the meta-analysis showed a significant difference between the combined studies. CONCLUSIONS: This study did not reveal any mutagenic effects, but based on the combined meta-analysis, we recommend the careful use of formocresol. CLINICAL RELEVANCE: This research helps to bring scientific evidence of the safe use of formocresol in deciduous pulpotomy treatments.

MMP20 rs1784418 Protects Certain Populations against Caries.

This work aimed to further evaluate the association of MMP20 rs1784418 C>T and dental caries experience with the hypothesis that MMP20 rs1784418 C>T is a risk factor for dental caries. 184 children 4-7 years of age had their caries experience determined and buccal cheek swabs collected for DNA extraction to test for association with the MMP20 rs1784418 C>T using standard statistical approaches. A meta-analytic approach was also implemented to compile previous discrepant reports of the same association. We found an association between MMP20 rs1784418 C>T and dental caries experience in primary dentition (p = 0.01). The meta-analysis showed that this association appears to favor individuals born in Brazil and not Turkey. MMP20 rs1784418 C>T appears to protect against dental caries, but its effects are likely to be more marked in certain populations.

Influence of sense of coherence on adolescents' self-perceived dental aesthetics; a cross-sectional study.

BACKGROUND: Sense of coherence (SOC) is a psychosocial factor capable of influencing perception of health, improving one's ability to manage life. It is the central construct of salutogenesis. SOC allows for identification and mobilization of resources to effectively manage or solve problems, promoting health and quality of life. Using Wilson-Cleary's conceptual model we hypothesized that SOC might contribute to self-perception of dental aesthetics. The aim of this study was to investigate whether SOC levels were related to self-perception of dental aesthetics against assessed normative orthodontic treatment need among adolescents. METHODS: A cross-sectional study was conducted with 615 male and female adolescents aged 12 to 15 years. Data collection comprised socio-demographic and socio-economic characteristics, SOC (SOC 13), self-perceived dental aesthetics (Oral Aesthetic Subjective Impact Scale), and assessment of orthodontic treatment need (Dental Aesthetic Index). Statistical analysis involved Pearson's chi-square test, Kruskal-Wallis test, Mann-Whitney test and multiple linear regression. Spearman's correlation coefficient was calculated for the determination of the strength of correlations among the numerical variables. The level of significance was set at 5% (p < 0.05). RESULTS: 50.1% of the participants were classified as having a high SOC (≥ median). Overall, SOC was associated with self-perceived dental aesthetics (p = 0.048). In the adolescents with no orthodontic treatment need, those with a low SOC perceived their dental aesthetics more negatively than those with high levels of SOC. The multiple regression analysis demonstrated an inverse relationship between SOC and: 1) age (p = 0.007), SOC being higher in the younger age group; 2) self-perceived dental aesthetics (p = 0.001), a higher SOC being associated with those who had a positive dental self-perception. CONCLUSIONS: SOC was associated with self-perceived dental aesthetics and adolescents with a high SOC were more likely to perceive their dental aesthetics more positively. SOC did not seem to influence self-perception of dental aesthetics in adolescents who were clinically assessed as having an orthodontic treatment need, however, in those where there was no orthodontic treatment need, a low SOC was associated with a negative self-perception of dental appearance.

An innovative approach to treating dental decay in children. A new anti-caries agent.

The aim of this work is to evaluate the antimicrobial and cytotoxic activity of a formulation containing silver nanoparticles and chitosan, provisionally called nano silver fluoride (NSF), against Streptococcus mutans in comparison to chlorhexidine and silver diamine fluoride (SDF). The product was characterised by transmission electron microscopy and UV-Vis absorption spectroscopy. The minimum inhibition concentration (MIC) was evaluated by the spectrophotometric microdilution method and turbidity. The minimum bactericide concentration (MBC) was evaluated in brain heart infusion plates, and cytotoxicity was evaluated by haemolytic activity. The MIC and MBC for NSF were, respectively, 33.54 ± 14.52 and 50.32 µg/mL; for SDF were 33.33 ± 14.43 and 50.0 µg/mL, respectively; and for CHX were 3.3 ± 0.5 and 6 µg/mL, respectively. An ANOVA for MIC gave P = 0.032, and for MBC P = 0.035. The cytotoxic effect of NSF compared to SDF demonstrated a statistically significant difference in the MIC value (t test P < 0.05). The NSF formulation may be effective against S. mutans with much lower doses, may have lower toxicity than SDF, and may not stain teeth.

Early childhood caries and its relationship with perinatal, socioeconomic and nutritional risks: a cross-sectional study.

BACKGROUND: Socioeconomic, perinatal and other life cycle events can be important determinants of the health status of the individual and populations. This study aimed to assess the prevalence of early childhood caries (ECC), perinatal factors (gestational age, teenage pregnancy and birth weight), family income and nutritional risk in children. METHODS: A cross-sectional study in which 320 children were examined according to the criteria established by the World Health Organization. A previously validated questionnaire was used to obtain information from parents and guardians about family income, gestational age and birth weight. To check the nutritional risk, we used the criteria provided by the CDC (Center for Disease Control). For Statistics, Pearson's, chi-square and the multivariate Poisson analyses were used to determine the association among variables. RESULTS: Approximately 20% of children had ECC, and the Poisson multivariate analyses indicated that family income (p = 0.009), birth weight (p < 0.001) and infant obesity (p < 0.001) were related to the increase of ECC, and gestational age was not significantly associated with ECC (p = 0.149). Pregnancy in adolescence was not included in the regression analyses model because it was not statistically significant in the chi-square test (p > 0.05). CONCLUSION: The prevalence of ECC was related to low family income, premature birth and infant obesity.

Efficacy of a high concentration of nano silver fluoride in preventing caries: A randomized controlled trial.

Background: To investigate the effectiveness of a novel agent containing Nano Silver Fluoride 1500 (NSF 1500) and chitosan to inactivate carious lesions in children. Material and Methods: The study included eighty children. While both groups had fluoride dentifrice applied to their teeth, only the experimental group received treatment with the NSF 1500-ppm solution. The first and sixth-month interval examinations were conducted by two calibrated dentists (k = 0.85). Results: The NSF 1500 group had 69.2% of their teeth with arrested decay, while the control group had 24.1%. The difference was statistically significant (p 0.001), with a preventive fraction of 59.4%. The number needed to treat (NNT) was approximately two. The NSF 1500 formulation was more effective than toothbrushing alone with fluoridated dentifrice in preventing dental caries. Conclusions: The effectiveness of NSF 1500 is determined by the size and depth of the dental cavity. Its ability to arrest caries lesions was comparable to previously tested products, NSF 400 and NSF 600. Key words:Preventive dentistry, dental caries, nanoparticles.

Sense of Coherence and Oral Health in Children and Adolescents: a Scoping Review.

PURPOSE: The purpose of this study was to review the published studies that address the sense of coherence and its relationship with the oral health of children and adolescents. METHODS: This scoping review was structured according to the review method proposed by the Joanna Brigs Institute and conducted in accordance with PRISMA-ScR guidelines. The research was carried out in the following databases: Medline/ Pubmed®, Lilacs®, Scopus©, Cochrane©, Web of Science©, and Embase©. RESULTS: In this search, 358 studies were found, seven in Cochrane, 90 in PubMed®, three in Lilacs®, 101 in Web of Science©, 80 in Scopus©, and 77 in Embase©, totaling 24 publications. The studies were published in nine countries, most of them cross-sectional studies. CONCLUSIONS: Most studies have shown that a high sense of coherence (SOC) of both the caregiver and the child/adolescent is related to better oral health behaviors and a lower caries index. No conclusive information was observed on the relationship between SOC and periodontal diseases.

An exploratory study of children with caries and its relationship to SARS-CoV-2.

This exploratory study investigated whether children with dental decay were more likely to have COVID-19 than those without caries. The children underwent dental inspection and blood collection for detection of SARS-CoV-2 antibodies. Fifty-four children aged 6 to 9 years participated in the survey, which was conducted between March and June 2020 in the municipality of Ipojuca, Pernambuco, Brazil. The diagnosis of caries was performed using the dmft and DMFT indices. Parents reported signs and symptoms of sickness in their children during this period. The serology test aimed to verify the immune response of the children to coronavirus by detecting IgM/IgG antibodies. Statistical analyses were performed at P < 0.05. The majority of the children presented caries (68.5%). Of the nine children who tested positive for COVID-19 (16.7%), eight presented IgG antibodies to the virus, and only one had IgG and IgM antibodies to SARS-CoV2. Children who tested positive for SARS-CoV-2 had a higher percentage of caries lesions than those who tested negative for SARS-CoV-2 (77.8% vs 65.9%), but this difference was not statistically significant.

Genotoxic effect of formocresol pulp therapy of deciduous teeth.

OBJECTIVE: To investigate whether formocresol, in Buckley's original formulation, used for pulp therapy of deciduous teeth, can have a genotoxic effect. Genotoxicity was tested in lymphocyte cultures from the peripheral blood of children aged 5-10y, in Recife, Pernambuco, Brazil. This was a case-control study. The sample comprised 40 children who had primary teeth with non-vital pulps. Two venous blood samples (6-8ml) were collected from each child, the first prior to pulp therapy (control group) and the second 24h after pulp therapy (experimental group). Lymphocyte cultures were grown in 78% RPMI 1640 medium, 20% fetal bovine serum, 2% phytohemagglutinin. The lymphocytes were assessed for chromosomal aberrations; each sample involved analysis of 100 metaphases. There was a statistically significant difference between the control and treated groups for the isochromatid gap (p<0.001), chromatid break (p<0.009), isochromatid break (p<0.046), other chromosomal alterations (p<0.001), and for total aberrations. In view of these results, caution in the use of formocresol in pediatric dentistry is recommended.

Paradigm shift in the effective treatment of caries in schoolchildren at risk.

BACKGROUND: Silver diamine fluoride (SDF) is an effective agent for the arrest of caries in children, is easy to apply and can be used outside the clinical environment. Interim restorative treatment (IRT) using glass ionomer cement has also been claimed to be a simple and effective method to arrest caries in deciduous teeth. OBJECTIVE: To examine whether, for underprivileged schoolchildren with cavities, treatment with 30% SDF gives better results than IRT for carries arrest. METHOD: This randomised controlled study compares the effect of IRT (FUJI IX) with 30% SDF in 91 children aged 5-6 years. RESULTS: After 1 year, treatment with SDF was more effective [relative risk (RR) = 66.9%] than IRT (RR = 38.6%) for the arrest of caries; this was statistically significant (P < 0.05). CONCLUSION: The SDF technique showed better results than IRT for the arrest of cavities in deciduous teeth, indicating that its use for underprivileged communities may justify a paradigm shift in paediatric dentistry.

Viral symptoms in children and SARS-COV-2: information for pediatric dentists for the control of transmission.

The new coronavi rus, which has spread worldwide, has spiraled out of control in Brazil. The number of infected children has increased, and more Infants Special Care Units are needed to prevent deaths. This study aims to report the most common signs and symptoms in children infected by seasonal respiratory viruses and those infected by COVID-19. This knowledge is essential to educate pediatric dentists, who may contribute to identifying the difference in symptoms and notify the cases, thus preventing the spread of COVID-19. This study was carried out in a Family Health Center of Ipojuca, state of Pernambuco, Brazil, and included 54 children seen for dental emergency care. The parents provided information about the signs and symptoms of their children' s health conditions during the lockdown from March to July 2020. All children had a serological test to detect any exposure to the virus. Kolmogorov-Smirnov and Mann-Whitney tests were used to assess the distribution of the data and compare the quantitative variables between the groups. Among the study participants, 16.7% tested positive for COVID-19. The most prevalent symptoms were headache (38.9%), sneezing (35.2%), and fever (20.4%); six out of nine children with a positive test had symptoms after infection of an adult in the family. Children infected with COVID-19 showed similar clinical signs to those with negative results. Pediatric dentists should acquire knowledge to report on sick children and prevent the spread of the disease.

Oral manifestations in hospitalized children with COVID-19.

As the pandemic progressed, the incidence of viruses among children also increased. This study investigates the presence of oral lesions in hospitalized children by analyzing data collected from medical records of infants seen at the pediatric Infectious disease unit at the General Hospital of the University of Pernambuco, Recife, Brazil, from March to August 2020. This study includes children aged 0 to 12 years diagnosed with severe symptoms of COVID-19. The data describe the frequencies and percentages of categorical variables, expressed as mean, median, and standard deviation. The chi-square test evaluated the association of oral manifestations according to the presence of comorbidities. Of 89 children, 20.2% had oral manifestations, and mucositis was the most prevalent lesion (12.4%). Of the 18 children with oral manifestations, 12 did not present comorbidities, but 7.9% had multisystem inflammatory syndrome and 5.6% had Kawasaki disease. Results show that children with oral lesions had longer hospital stays. These findings indicate the need for further studies to clarify the relationship between the oral manifestations of COVID-19 in pediatric patients for screening of the virus by dentists.

Prevalence of banding and bonding molar brackets in orthognathic surgery cases.

PURPOSE: Orthodontic treatment in the orthognathic surgical patient commonly involves banding or bonding of erupted molars. Appliance displacement during surgery is a potentially serious complication. However, limited data exist about the prevalence of banding or bonding and the frequency of appliance failure in this patient population. The purpose of this study was to determine the prevalence of banding and bonding and appliance failure in a large cohort of patients undergoing orthognathic surgery at a single institution. PATIENTS AND METHODS: All patients who underwent orthognathic surgery from 2004 to 2006 at Kaiser Permanente Oakland Medical Center were identified, and preoperative and postoperative radiographs were retrospectively reviewed. Study variables included age at time of surgery, gender, date and type of surgery, Angle classification of occlusion, type of orthodontic appliance (band or bond) on erupted molar teeth, and failure as detected from postoperative imaging. RESULTS: In the 1,003 patients there was a greater overall prevalence of molar bands (74.3%) than bonds (19.2%) with the vast majority (84.4%) of first molars and fewer (64.2%) second molars having banded appliances. The prevalence of bonded first and second molars was lowest in 2004 and highest in 2006. Appliance failure occurred in 19 patients (1.9%), most often involving maxillary second molars, and all were bonds. Of the 19 failed bonds, 2 were displaced into the mandibular osteotomy site and 1 was displaced into the posterior pharynx. CONCLUSION: The prevalence of bonded molars in surgical patients increased from 2004 to 2006. Appliance malfunction occurred most often in bonded maxillary second molars. Although rare, failure and displacement of bonded appliances may have significant consequences.

Treatment of posterior crossbite comparing 2 appliances: a community-based trial.

INTRODUCTION: The aim of this community-based trial was to compare the effectiveness of the quad-helix appliance and removable plates for treating posterior crossbite. METHODS: Ninety-nine patients were randomly divided into 3 groups: quad-helix, expansion plate, and untreated. All subjects were in the mixed dentition, had posterior crosssbite, no sucking habits, no previous orthodontic treatment, and no Class III malocclusion. The following aspects were evaluated: posterior crossbite correction, maxillary and mandibular intermolar and intercanine expansions, length of treatment, cost-benefit analysis, success rate, and number of complications. RESULTS: The length of treatment and the costs were higher in the expansion plate group than in the quad-helix group. The success rates were similar for the quad-helix and the expansion plate groups, and the number of complications was higher in the quad-helix group. No self-correction was observed in the untreated group, and relapses occurred in both experimental groups. CONCLUSIONS: The average treatment time was significantly shorter and 11% less expensive than in the quad-helix group, making it the more cost-effective choice for treatment.

Nano-silver Fluoride at Higher Concentration for Caries Arrest in Primary Molars: A Randomized Controlled Trial.

AIM AND OBJECTIVE: To compare the arresting caries effectiveness of two different silver nanoparticle (AgNP) concentrations of nano-silver fluoride (NSF), namely 400 and 600 ppm. The hypothesis is that in posterior primary teeth with occlusal and approximal active dentin carious lesions, NSF 600's effectiveness will be higher than that of the NSF 400 solution over a 6-month follow-up period. MATERIALS AND METHODS: This was a double-blind randomized clinical trial (RCT) conducted in the city of Recife, Brazil. A total of 337 children aged 5-7 years who attended the University of Pernambuco Dental School's clinics were examined. A single-blinded investigator conducted the examinations and treatment of the children. After baseline examination and recording of the dmft index, children were allocated to one of two study groups (NSF 600-intervention and NSF 400-positive control). In both groups, each tooth received two drops of NSF and treatments were performed only once in 6 months. The follow-up examinations were visual and tactile, performed in 30, 90, and 180 days to determine the activity of caries. The carious lesions that were not arrested in 30 days were recorded and referred for restorative treatment. RESULTS: The NSF 600 showed higher rate of success in arresting caries (72.7%, p = 0.025) compared with NSF 400 (56.5%). CONCLUSION: The higher rate of success of NSF 600 can be explained by the higher concentration of AgNPs. CLINICAL SIGNIFICANCE: Nano-silver fluoride has emerged as an excellent alternative to silver diamine fluoride (SDF), as it adds a high antibacterial effect to better esthetic results. Treatment is simple, non-invasive, and incurs low cost. It is ideal for use in community-based programs to increase the access to dental care without staining teeth black like other silver products. HOW TO CITE THIS ARTICLE: Arnaud M, Junior PCM, Lima MGS, et al. Nano-silver Fluoride at Higher Concentration for Caries Arrest in Primary Molars: A Randomized Controlled Trial. Int J Clin Pediatr Dent 2021;14(2):207-211.

Anterior open bite: a case-control study.

OBJECTIVE: The aim of this study was to assess the influence of sucking habits and facial pattern measurements on the development of anterior open bite (AOB). METHODS: A case-control study was carried out on 60 children aged 7 and 8 years attending municipal public schools in the city of Recife, Brazil. Data collection included interviews with guardians, oral examinations, and facial growth pattern analysis using cephalometric radiographs. The following cephalometric measurements were assessed: SN.Gn, SN.GoGn, FMA, and Facial Axis. Statistical analyses were performed using the Student's t-test and Pearson's chi-square test at a 5% level of significance. RESULTS: The percentage of children with sucking habits in the case group was much higher than in the control group (53.3%vs 16.7%) (P = 0.003). Children with sucking habits were six times more likely to develop AOB. Regarding the measurements assessed, no statistically significant differences were observed between groups. CONCLUSION: This study found no evidence that variations in cephalometric angles (SN.Gn, FMA, SN.GoGn, and facial axis) are risk factors for AOB. Only sucking habits demonstrated a positive correlation with an increased AOB.

The best treatment for avulsed permanent teeth.

DATA SOURCES: The Cochrane Oral Health Group's Trials Register, Cochrane CENTRAL, Medline and Embase were consulted, along with the websites www.clinicaltrials.gov and www.controlled-trials.com and reference lists of identified articles. There were no language restrictions. STUDY SELECTION: Only randomised controlled trials that included a minimum followup period of 12 months for interventions dealing with avulsed and replanted permanent teeth were considered. DATA EXTRACTION AND SYNTHESIS: Two review authors independently extracted data and assessed trial quality and the risk of bias in studies to be included. RESULTS: Three studies (involving, in total, 162 patients and 231 teeth) were included. Study one (high risk of bias) investigated the effect of extra-oral endodontics. This showed no significant difference in radiographic resorption compared with intra-oral endodontics provided at week 1 for teeth avulsed for longer than 60 min dry time. Study two (moderate risk of bias) investigated a 10-min soaking in thymosin alpha 1 prior to replantation and then its further use as a daily gingival injection for the first 7 days. They reported a strong benefit at 48 months (14% with periodontal healing in the control group versus 77% for the experimental group). Study three (high risk of bias) investigated a 20-min soaking with gentamycin sulphate for both groups prior to replantation and then the use of hyperbaric oxygen daily in the experimental group for 80 min for the first 10 days. They reported a strong benefit at 12 months (43% periodontal healing versus 88% for the experimental group). There was no formal reporting of adverse events. CONCLUSIONS: The available evidence suggests that extra-oral endodontic treatment is not detrimental for teeth replanted after more than 60 min dry time. Studies with moderate/ high risk of bias indicate that soaking in thymosin alpha 1 and gentamycin sulphate followed by hyperbaric oxygen may be advantageous but these strategies have not previously been reported as interventions for avulsed teeth and await further validation. More evidence with low risk of bias is required and, with the low incidence of avulsed teeth, collaborative multicentre trials are indicated.