Improving accuracy of early dental carious lesions detection using deep learning-based automated method

OBJECTIVE

To investigate the effectiveness of a convolutional neural network (CNN) in detecting healthy teeth and early carious lesions on occlusal surfaces and to assess the applicability of this deep learning algorithm as an auxiliary aid.

MATERIALS AND METHODS

A total of 2,481 posterior teeth (2,459 permanent and 22 deciduous teeth) with varying stages of carious lesions were classified according to the International Caries Detection and Assessment System (ICDAS). After clinical evaluation, ICDAS 0 and 2 occlusal surfaces were photographed with a professional digital camera. VGG-19 was chosen as the CNN and the findings were compared with those of a reference examiner to evaluate its detection efficiency. To verify the effectiveness of the CNN as an auxiliary detection aid, three examiners (an undergraduate student (US), a newly graduated dental surgeon (ND), and a specialist in pediatric dentistry (SP) assessed the acquired images (Phase I). In Phase II, the examiners reassessed the same images using the CNN-generated algorithms.

RESULTS

The training dataset consisted of 8,749 images, whereas the test dataset included 140 images. VGG-19 achieved an accuracy of 0.879, positive agreement of 0.827, precision of 0.949, negative agreement 0.800, and an F1-score of 0.887. In Phase I, the accuracy rates for examiners US, ND, and SP were 0.543, 0.771, and 0.807, respectively. In Phase II, the accuracy rates improved to 0.679, 0.886, and 0.857 for the respective examiners. The number of correct answers was significantly higher in Phase II than in Phase I for all examiners (McNemar test;P<0.05).

CONCLUSIONS

VGG-19 demonstrated satisfactory performance in the detection of early carious lesions, as well as an auxiliary detection aid.

CLINICAL RELEVANCE

Automated detection using deep learning algorithms is an important aid in detecting early caries lesions and improves the accuracy of the disease detection, enabling quicker and more reliable clinical decision-making.

Is oral health literacy associated with conceptions of care and behavior related to the prevention of COVID-19?

The aim of the present study was to investigate the impact of oral health literacy (OHL) on conceptions of care and behaviors related to COVID-19. The sample came from two preliminary cross-sectional studies that determined the level of OHL of parents/guardians of six-to-12-year-old children in two major Brazilian cities (Curitiba and Belo Horizonte). Functional OHL was measured using the Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30) and the Health Literacy Dental Scale (HeLD-14) for the evaluation of interactive OHL. Participants were recruited through e-mail, social media, and telephone contact. The questionnaire on conceptions of care and behaviors related to COVID-19 was created based on the guidelines of the World Health Organization. Two hundred nineteen individuals participated in the study. There was no significant difference in socioeconomic and demographic variables and in the medians of BREALD and HeLD-14 between the two cities (P>0.05). Higher levels of functional OHL were associated with an appropriate conception that individual care affects collective care (P=0.038), but with an inappropriate conception of seeking medical assistance in cases of mild symptoms (P=0.030). Higher levels of interactive OHL were related to social distancing behavior in the city of Curitiba (P=0.049) and in the overall sample (P=0.040). It is concluded that functional OHL was associated with two of the investigated conceptions about COVID-19, while interactive OHL was associated with social distancing behavior. These data may suggest that different dimensions of the OHL can have an impact on different aspects of coping with the pandemic.

Are technology-based health education methods able to reduce oral health inequalities between the sexes in adolescents? A cluster randomized trial

PURPOSE

Determine if different technology-based health education interventions can reduce oral health inequalities between the sexes in a sample of adolescents.

METHODS

A cluster randomized clinical trial was conducted in three phases with an initial sample of 291 male and female adolescents 14-19 years of age. Phase I (n = 288) comprised a clinical examination performed by a calibrated examiner using the simplified oral hygiene index (OHI-S) and gingival bleeding index (GBI). Phase II involved two educational interventions: video (VD; n = 147) or oral counselling (OR; n = 141) with standardized content. In phase III, an App was made available to half of the clusters (OR + App; n = 66/OR without App; n = 71/VD + App; n = 63/VD without App; n = 63), and the clinical examination was performed a second time. Data were evaluated using descriptive analysis and nonparametric tests.

RESULTS

In phase I, boys had a lower standard of oral hygiene compared with girls, with higher mean OHI-S (p = 0.039) and GBI (p = 0.015). After VD and OR interventions, no significant difference between sexes was found regarding the mean OHI-S. However, males had a higher mean GBI compared with females in the OR group (p = 0.006). When the App was added to OR and VD groups, males in the 'OR without App' group had a higher mean GBI compared with females (p = 0.007).

CONCLUSION

This clinical trial demonstrated that educational interventions involving information technologies were effective at reducing oral health inequalities between the sexes among adolescents. However, oral counselling alone was not efficient in reducing GBI in male adolescents.

Urgency and discontinuity of oral health care in children and adolescents

The aim of the present study was to investigate the discontinuity of oral health care among children and adolescents who accessed emergency services at primary care units and urgent care units. Records were reviewed of patients aged 0 to 17 years treated in the public healthcare system in city of Curitiba, Brazil. Discontinuity was considered when elective treatment was not registered at the primary care unit within six months after urgent care. The sample was stratified based on the Municipal Human Development Index (MHDI) (≤0.799 or ≥0.800). The association between discontinuity and covariables was assessed using univariate and multivariate Poisson regression models with robust variance (α=0.05). The incidence of discontinuity was 42.2%. In the MHDI≤0.799 stratum, the risk of discontinuity was greater among children younger than five years of age and individuals who had not had a dental appointment in the previous year. In both MHDI strata, the risk of discontinuity was higher in patients who received urgent care at an urgent care unit than those treated at a primary care unit. The incidence of the discontinuity of oral health care was high and was strongly influenced by the characteristics of dental service utilization among individuals living in regions with a lower MHDI.

Adhesive restoration of molars affected by molar incisor hypomineralization: a randomized clinical trial

OBJECTIVE

This randomized clinical trial evaluated the survival of direct restorations on first permanent molars (FPMs) with molar incisor hypomineralization (MIH) and its impact on self-reported dental pain and dental anxiety.

MATERIAL AND METHOD

FPMs with MIH of 35 patients aged 7 to 16 years were included. The FPMs were randomized into the following two groups: total-etch (TE-37% phosphoric acid etching) and self-etch (SE-no prior etching). The FPMs were restored with universal adhesive and bulk-fill resin composites. The restoration survival was evaluated according to USPHS criteria modified by a blinded examiner. Dental anxiety (Venham picture test) and dental pain (Faces pain scale-revised) were evaluated before treatment and at 1, 6, and 12 months post-treatment. Survival rates were analyzed by the Kaplan-Meier method and the log-rank test. Nonparametric tests compared pain and anxiety in the follow-up periods.

RESULTS

A total of 64 FPMs were restored (TE = 33; SE = 31). Survival rates were 96.9% (TE) and 96.7% (SE) after 1 month, 90.5% (TE) and 80.6% (SE) after 6 months, and 80.8% (TE) and 62.3% (SE) after 12 months (p > 0.05). Self-reported dental pain and anxiety level decreased after treatment in both groups (p < 0.05). Self-reported pain decreased after 1 month in SE, but it occurred at 6 months in TE.

CONCLUSION

Both restorative protocols presented similar longevity, decreasing self-reported pain and anxiety levels.

CLINICAL RELEVANCE

A universal adhesive could be appropriate for restoration of MIH-affected teeth, and the survival of restorations could be higher in the total-etch technique, reducing dental pain and anxiety.

Are Information Technologies Capable of Stimulating the Use of Dental Floss by Adolescents? A Cluster Randomised Clinical Trial

PURPOSE

To analyse the effect of information technologies on improving the frequency of the use of dental floss among adolescents.

MATERIALS AND METHODS

A randomised, controlled clinical trial was conducted with 291 adolescents (mean age: 16.1 years) in three phases. Phase I involved the application of a questionnaire and clinical examinations using the simplified Oral Hygiene Index and gingival bleeding index. In phase II, the adolescents were randomly allocated to four groups: oral counseling (OR) and the use of an application (App) for smartphones; OR without the app; video (VD) and app; and VD without app. Messages were set through the app for 30 days. Phase III involved the second administration of the questionnaire and clinical examination. The frequency of dental floss use was evaluated in phases I and III. The groups were categorised into the use of technology (VD and/or App) and non-use of technology (OR alone).

RESULTS

Statistically significant reductions in the clinical indices were found with all educational methods (p < 0.005) and improvements were found in the use of dental floss (p < 0.001). Moreover, information technologies were associated with an improvement in the frequency of dental floss use (p < 0.033).

CONCLUSION

All methods were effective at improving clinical indicators. The use of information technologies can be considered an effective tool for improving dental floss use among adolescents.

Systemic Exposures Associated with Hypomineralized Primary Second Molars

Purpose: Hypomineralized primary second molars (HPSMs) are clinically represented by demarcated opacities in the enamel, involving from one to four primary second molars. The purpose of this cross-sectional study was to investigate the systemic exposures associated with hypomineralized primary second molars. Methods: A representative population-based sample of 731 eight-year-old children was randomly selected. Data on systemic exposures were collected via a structured questionnaire given to the children's mothers. The HPSMs were clinically assessed by calibrated examiners according to the modified-DDE (developmental defects of enamel) index and European Academy of Paediatric Dentistry criteria. Associations were analyzed by Poisson multiple regression considering a temporal hierarchical approach. Results: The prevalence of HPSMs was 9.4 percent (95 percent confidence interval equals 7.0 to 12.0 percent). Children whose mothers presented with hypertension were found with an Adjusted Prevalence ratio (PRa) of 1.73 (P=0.044) and mothers who used tobacco (PRa equals 2.44; P=0.001) during pregnancy had a significantly higher prevalence of HPSMs. The presence of complications during delivery (PRa equals 1.83; P=0.032) and the occurrence of otitis media during early childhood (PRa equals 1.68; P=0.043) also presented a higher prevalence of HPSMs. Conclusion: The use of tobacco, presence of hypertension, complications during delivery, and otitis media during the first years of a child's life are associated with a higher prevalence of hypomineralized primary second molars. (Pediatr Dent 2019;41(5):364-70).

Dental anxiety in schoolchildren with molar incisor hypomineralization-A population-based cross-sectional study

BACKGROUND

Identifying patients with high levels of DA helps to define the most adequate oral healthcare strategy, especially for pediatric patients.

AIM

To investigate the association between parental reports of dental anxiety (DA) and molar incisor hypomineralization (MIH) in schoolchildren.

DESIGN

A cross-sectional study was conducted in a representative sample of 731 8-year-old schoolchildren from the city of Curitiba, Brazil, who were clinically examined (k ≥ 0.75) for the diagnosis of MIH and dental caries using the EAPD criteria and dmft/DMFT index, respectively. Parents/guardians reported children's DA using the Dental Anxiety Question (DAQ) and answered a self-administered structured questionnaire addressing socioeconomic and demographic characteristics. Associations were evaluated using Poisson regression analysis with robust variance (P < 0.05).

RESULTS

A significant association was found between DA and MIH (PR = 1.20; 95%CI: 1.01-1.42; P = 0.038), but this association lost its significance when adjusted for the other characteristics (PR = 1.13; 95%CI: 0.93-1.38; P = 0.215). Caries experience in primary teeth was associated with lower levels of DA (PR = 0.83; 95%CI: 0.71-0.96; P = 0.0013). The most recent visit to the dentist due to pain increased the levels of DA (PR = 1.18; 95%CI: 1.07-1.30; P = 0.001).

CONCLUSIONS

The presence of MIH in schoolchildren was not associated with parental reports of DA.

Demarcated opacity in primary teeth increases the prevalence of molar incisor hypomineralization

This cross-sectional study aimed to assess the prevalence of molar incisor hypomineralization (MIH) and its relationship with the number of primary teeth with developmental defects of enamel (DDE). A representative population-based sample of 731 schoolchildren was randomly selected from the public school system in Curitiba, Brazil. Schoolchildren aged 8 years with fully erupted permanent first molars and incisors were eligible for the study. MIH and DDE were classified by four calibrated examiners (kappa > 0.75) according to EAPD criteria and to the FDI-modified DDE index. Clinical data were collected in a school environment. Socioeconomic information was collected through a self-administered semistructured questionnaire applied to the children's caregivers. Statistical analyses were carried out using Poisson multiple regression with robust variance (α = 0.05). MIH prevalence was 12.1% (95%CI: 10-15), and opacities were the most prevalent defect. Socioeconomic factors were not associated with MIH. Children with demarcated opacity in primary teeth presented a higher prevalence of MIH than those without DDE in primary teeth. In the multiple analysis, the increase of one primary tooth affected by demarcated opacity increased the prevalence of MIH by 33% (PR = 1.33, 95%CI: 1.15-1.53, p < 0.001). Asian children had a higher prevalence of MIH (PR = 2.91, 95%CI: 1.08-8.09 p = 0.035) than did Caucasian children.Conclusion: Based on these findings, the prevalence of MIH in Curitiba was 12.1%. Demarcated opacity in primary teeth could be considered a predictor of MIH.

Impact of molar incisor hypomineralization on quality of life in children with early mixed dentition: A hierarchical approach

BACKGROUND

Molar incisor hypomineralization (MIH) is associated with unfavourable dental conditions such as dental caries and may consequently impact oral health-related quality of life (OHRQoL).

OBJECTIVE

To assess the impact of MIH on OHRQoL in children with early mixed dentition.

METHOD

A population-based cross-sectional study of 728 8-year-old children from the public school system in Curitiba, Brazil, was conducted. The Child Perception Questionnaire for 8- to 10-year-olds (CPQ_8-10 ) was used to evaluate OHRQoL. MIH was diagnosed according to the European Academy of Paediatric Dentistry (EAPD) criteria. The assessments of MIH, dental caries, and malocclusion were performed by four calibrated examiners (κ ≥ 0.80). Demographic and socioeconomic data (DSE) were obtained from the children's parents/caregivers using a structured questionnaire. The analysis of OHRQoL determinants was performed through a three-level hierarchical approach: mesial (DSE), intermediate (clinical conditions), and distal (child's oral self-perception), using Poisson regression with robust variance (α = 0.05).

RESULTS

The prevalence of MIH was 12.1% (95% CI: 10-15). An association was found between MIH and OHRQoL in the "oral symptoms" domain of the CPQ_8-10 (PR: 1.07, 95% CI: 1.03-1.11, P < 0.001) after adjusting for other clinical variables and DSE.

CONCLUSION

Molar incisor hypomineralization was associated with a greater impact on OHRQoL in children's oral symptoms.

A systematic review and meta-analysis of systemic exposure associated with molar incisor hypomineralization

OBJECTIVE

To evaluate systemic exposures associated with molar incisor hypomineralization (MIH).

METHODS

This systematic review was performed using published observational studies that evaluated the systemic exposures associated with MIH. The sources of articles searched were PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library and Grey literature. The risk of bias was analysed according to the Newcastle-Ottawa Scale for quality assessment. The meta-analysis was performed considering the exposures during the prenatal, perinatal and postnatal periods using the CMA software.

RESULTS

A total of 4207 articles were identified. Twenty-nine studies were eligible for inclusion and 27 were included in the meta-analysis. The studies presented low and moderate risks of bias, except for one that was classified as having a high risk of bias. Maternal illness during pregnancy (OR 1.40; 95% CI 1.18-1.65, P < 0.0001) and psychological stress (OR = 2.65; 95% CI 1.52-4.63; P = 0.001) was observed to be significantly associated with higher odds of MIH. During the perinatal period, caesarean delivery (OR = 1.32, 95% CI 1.11-1.57, P = 0.001) and delivery complications (OR = 2.06; 95% CI 1.47-2.88, P < 0.0001) were also associated with MIH. In the postnatal period, only respiratory diseases (OR = 1.98; 95% CI 1.45-2.70, P < 0.0001) and fever (OR = 1.50; 95% CI 1.22-1.84; P < 0.0001) were associated with higher prevalence of MIH. The evidence was graded as very low quality.

CONCLUSIONS

Maternal illness, psychological stress, caesarean delivery, delivery complications, respiratory diseases and fever during the first years of a child's life were significantly associated with a higher odds of MIH. However, this should be interpreted with caution, once the primary studies were observational, with serious limitations according to the risk of bias, imprecision, and inconsistency. Further, well-designed cohort studies are still required.

Improving adolescents' periodontal health: evaluation of a mobile oral health App associated with conventional educational methods: a cluster randomized trial

BACKGROUND

Adolescence is a decisive period in the construction of new conduits.

OBJECTIVE

The influence of an App associated with conventional educational methods in adolescents' oral health.

STUDY DESIGN

Randomized controlled trial including 291 participants (mean age = 16.1 years) in baseline. The study consisted of four phases. Interventions were evaluated through the knowledge score (KS) and oral indexes (OHI-S/GBI). KS was obtained through five affirmations about periodontal diseases applied in different moments (pre-test, post-test, and follow-up test). Phase I included pre-test and oral clinical examination. Sample was randomly divided into two groups: oral (OG) and video orientation (VG) and post-test (phase II). Phase III characterized the formation of groups: OG + App/OG without App/VG + App/VG without App. App consisted of reinforcement messages which was sent during 30 days. Phase IV comprised follow-up test and clinical evaluation.

RESULTS

There was no significant difference in KS between OG/VG. Overall, App improved KS (P < 0.001). VG + App showed a significant increase in KS in the follow-up test compared to the post-test (P = 0.046). There was a significant reduction in oral indexes for all methods.

CONCLUSION

App was effective in increasing knowledge, especially associated with video. The different methods were equally effective for a better standard in oral hygiene.

Oral Health Literacy as a Predictor of Dental Anxiety in Parents of Children Undergoing Dental Treatment

PURPOSE

The purpose of this cross-sectional study was to evaluate the association between parents' dental anxiety (DA) and independent variables.

METHODS

One hundred sixty-eight dyads of parents and six- to 12-year-old children who were undergoing treatment at a university pediatric dentistry clinic were recruited. Two examiners evaluated parents' DA and oral health literacy (OHL) using the Brazilian version of Corah's dental anxiety scale and the Brazilian Rapid Estimate of Adult Literacy in Dentistry (BREALD-30), respectively. Children's DA was reported by parents through the dental anxiety question (DAQ). Demographic data was also collected. A single examiner used the decayed, missing, and filled permanent teeth and primary teeth (DMFT/dmft) indices to assess the children's oral health status. The data analysis involved univariate and multivariate Poisson regression.

RESULTS

In the multivariate regression, higher levels of parents' DA were associated with a household income equal to or less than the Brazilian monthly minimum wage (prevalence ratio [PR]=4.9; 95 percent confidence interval [CI]=2.1 to 11.7) and a lower degree of OHL (PR=1.68; 95 percent CI=1.01 to 2.8). Associations between parents' DA and children's DA and DMFT/dmft index were not found.

CONCLUSION

Parents' dental anxiety was related to a low household income and low oral health literacy.

Oral Health Literacy and Retention of Health Information Among Pregnant Women: A Randomised Controlled Trial

PURPOSE

This study evaluated the effect of oral health literacy (OHL) on the retention of health information in pregnant women.

MATERIALS AND METHODS

A total of 175 pregnant women were randomly assigned to standard oral (spoken), written and control intervention groups. With the exception of the control group, the interventions investigated the eating habits and oral hygiene among children under 2 years of age. The participants' answers before the interventions (pre-test), 15 min after the interventions (post-test) and 4 weeks after the interventions (follow-up test) were used to estimate the knowledge score (KS). Information acquisition was determined by comparing pre-test and post-test results, while retention of information was based comparing pre-test and follow-up test results. OHL was analysed by BREALD-30. The data were assessed by nonparametric tests and Poisson regression models with robust variance (α = 0.05).

RESULTS

By the end of the follow-up period, 162 pregnant women had been assessed. The BREALD-30 mean was 22.3 (SD = 4.80). Regardless of the type of intervention, pregnant women with low OHL had lower knowledge scores in the three assessments. Participants with low OHL showed higher acquisition and retention of information in the standard oral health intervention. Multiple regression models demonstrated that OHL was independently associated with KS, age, socioeconomic status and type of intervention.

CONCLUSION

The results suggest a negative effect of low OHL on retention of information. Only the standard, spoken oral health intervention could address the differences in literacy levels.

Dental age estimation in Brazilian HIV children using Willems' method

The notification of the Human Immunodeficiency Virus (HIV) in Brazilian children was first reported in 1984. Since that time more than 21 thousand children became infected. Approximately 99.6% of the children aged less than 13 years old are vertically infected. In this context, most of the children are abandoned after birth, or lose their relatives in a near future, growing with uncertain identification. The present study aims to estimate the dental age of Brazilian HIV patients in face of healthy patients paired by age and gender. The sample consisted of 160 panoramic radiographs of male (n: 80) and female (n: 80) patients aged between 4 and 15 years (mean age: 8.88 years), divided into HIV (n: 80) and control (n: 80) groups. The sample was analyzed by three trained examiners, using Willems' method, 2001. Intraclass Correlation Coefficient (ICC) was applied to test intra- and inter-examiner agreement, and Student paired t-test was used to determine the age association between HIV and control groups. Intra-examiner (ICC: from 0.993 to 0.997) and inter-examiner (ICC: from 0.991 to 0.995) agreement tests indicated high reproducibility of the method between the examiners (P<0.01). Willems' method revealed discrete statistical overestimation in HIV (2.86 months; P=0.019) and control (1.90 months; P=0.039) groups. However, stratified analysis by gender indicate that overestimation were only concentrated in male HIV (3.85 months; P=0.001) and control (2.86 months; P=0.022) patients. The significant statistical differences are not clinically relevant once only few months of discrepancy are detected applying Willems' method in a Brazilian HIV sample, making this method highly recommended for dental age estimation of both HIV and healthy children with unknown age.

Bone marrow mesenchymal stem cells stimulated by bFGF up-regulated protein expression in comparison with periodontal fibroblasts in vitro

OBJECTIVE

The aim of this study was to evaluate, in vitro, the role of bFGF in the proliferation and expression of collagen type I and fibronectin of dog bone marrow mesenchymal stem cells (dBMMSCs) in comparison with the expression of the same proteins in dog periodontal fibroblasts (dPLFs).

DESIGN

dBMMSCs from the iliac crest were cultivated in Dulbecco's Modified Eagle's Medium (DMEM). Flow cytometry analysis (FCA) was used to characterize dBMMSC. Cells were stimulated with bFGF (1, 5 and 10 ng/mL) after 24 and 48 h. Real time RT-PCR was performed to verify collagen type I and fibronectin expressions. MTT assay was used to confirm cellular proliferation. Statistical analyses were performed (ANOVA and Kruskal-Wallis tests; p<0.05).

RESULTS

FCA showed 55.98% of CD34+ and 32.67% of CD90+ after bone marrow aspiration; 3.33% of CD34+ and 33.0% of CD90+ before P1. After P2, 10.54% of dBMMSCs expressed CD90, whereas after P3, this number decreased to 1.58%. dPLFs presented 4.04% of CD90+ and 1.05% of CD34+ after P3. MTT evaluation showed increase in dBMSC proliferation with 5 ng/mL bFGF-stimulus after 24-h. Both collagen I and fibronectin expression were very similar between the two cells groups after 24-h stimulation with 1 ng/mL bFGF concentration. Fibronectin and collagen I expressions were higher after 24-h stimulation with 5 ng/mL bFGF.

CONCLUSION

dBMMSCs (1 ng/mL-bFGF stimulus after 24 h) are very similar to dPLFs as regards morphological and immunostaining characteristics, and collagen and/or fibronectin production. The dBMMSCs presented the highest protein expression rates with 5 ng/mL-bFGF stimulus after 24-h.

Periodontal tissue engineering after tooth replantation

BACKGROUND

Blood-derived products, platelet-poor plasma (PPP) and platelet-rich plasma (PRP), constitute an approach in the enhancement of tissue healing. PRP has also been used as a scaffold for bone marrow stem cells in tissue engineering. This study evaluates the effect of PPP, calcium chloride-activated PRP (PRP/Ca), calcium chloride- and thrombin-activated PRP (PRP/Thr/Ca), and bone marrow mononuclear cells and PRP/Ca (BMMCs/PRP/Ca) on the healing of replanted dog teeth.

METHODS

After 30 minutes of extraction, teeth were replanted with 1) no material (control); 2) PPP; 3) PRP/Ca; 4) PRP/Thr/Ca; or 5) BMMCs/PRP/Ca. Histologic, histomorphometric, and immunohistochemical analysis was assessed 120 days after replantation. Data from histomorphometric analysis were analyzed statistically (analysis of variance, Tukey; P <0.05). Quantitative immunohistochemical analysis was analyzed by Kruskal-Wallis and Dunn post hoc test (P <0.05).

RESULTS

Flow cytometry analysis showed 55.98% of CD34(+) and 32.67% of CD90/Thy-1 for BMMCs sample. BMMCs/PRP/Ca presented the largest areas of replacement resorption characterized by osseous ingrowth into cementum (P <0.05), with intense immunomarcation for tartrate-resistant acid phosphatase. The PRP/Ca group also showed areas of replacement resorption with significant immunomarcation for osteopontin. PRP/Thr/Ca presented no replacement resorption. PPP showed areas of inflammatory resorption, with immunomarcation for tartrate-resistant acid phosphatase.

CONCLUSIONS

The results suggest that platelets activated with thrombin play an important role in the healing of tissues after tooth replantation. Additional studies are necessary to test other materials, because PRP/Ca did not present an appropriate scaffold for undifferentiated cells in the treatment of avulsed teeth.