Factor In Resorption Research Articles

The Fate of the Frozen Bone Flap: Quantitative and Volumetric Assessment Following Cranioplasty Using the Autologous Bone Flap.

The pattern, rate, and natural history of bone flap resorption following cranioplasty with frozen, autologous bone flap has not been fully defined. The authors sought to quantify the progression and natural history of bone flap resorption. Patients who had craniectomy and delayed cranioplasty with stored, frozen bone flap between 2012 and 2022 were included in this study. Ninety patients (63% male) were included, with a median age of 44.8 years (range: 4.2-84.4y) at the time of autologous bone flap cranioplasty. Delayed, autologous cranioplasty occurred at a median time of 29.5 days (range: 2d-10y) from the index craniectomy. The median follow-up was 16.6 months (range: 3.4-85.4mo). Radiographically quantifiable bone flap resorption occurred in 50 patients (56%). During the follow-up, the average percentage volume loss was 17%, with a nonlinear pattern of resorption. Following delayed, autologous cranioplasty, 11 patients had clinically significant bone flap resorption requiring secondary alloplastic cranioplasty at a median time of 13.8 months (range: 5.9-57.2mo), with a mean percentage volume loss of 61%. Younger age was a risk factor for bone flap resorption (P < 0.05), whereas active smoking, presence of comorbidities, and number of days of bone flap storage were not risk factors for bone flap resorption. Penalized B-spline regression analysis showed that bone flap resorption followed a nonlinear pattern. Radiographically quantifiable bone flap resorption occurred in about 56% of patients following delayed autologous cranioplasty. Resorption followed a non-linear pattern. Young age is a risk factor for bone flap resorption.

Factors affecting external apical root resorption of maxillary incisors associated with microimplant-assisted rapid palatal expansion.

To measure and compare the extent of root resorption in the maxillary incisors following microimplant-assisted rapid palatal expansion (MARPE) and to identify risk factors of root resorption after expansion. Cone-beam computed tomography images were obtained from a total of 60 patients both before expansion (T1) and 3 to 6 months after expansion (T2). Measurements taken included tooth length, root length, crown length and center of resistance. Resorption length (RL) and resorption length percentage (RLp), resorption volume (RV) and resorption volume percentage (RVp) and the amount of expansion were calculated. A significant difference in tooth length and volume was observed in both the central and lateral incisors before and after expansion. The resorption index (RL, RLp, RV, RVp) was significantly higher in the central incisors than in the lateral incisor. There was a significant correlation between several factors: age and RLp of the central incisors, the amount of expansion and RVp of the central incisors, tooth length of the central incisors and RL, RLp of the central incisors, root/crown ratio of the central incisors and RL of the central incisors, as well as tooth length of the lateral incisors and the RL of the lateral incisors. Significant root resorption occurs in maxillary incisors following MARPE, with central incisors root resorption being significantly higher than lateral incisors. Key risk factors for root resorption after MARPE include advanced age, a larger amount of expansion, initial tooth length, and a root/crown ratio.

Comparative Evaluation of Mandibular Ridge Resorption in Post-menopausal Denture and Non-Denture-Wearing Females and Its Relation to Body Mass Index: An In-Vivo Study.

Background Mandibular ridge resorption is a common problem in edentulous individuals, particularly in post-menopausal women. Body mass index (BMI) has been suggested as a potential factor influencing ridge resorption, but the relationship between the two remains unclear. Methods A study was conducted to evaluate mandibular ridge resorption in post-menopausal denture-wearing females and its relation to body mass index. A sample of 60 completely edentulous post-menopausal women was divided into two groups based on denture-wearing status and BMI. A radiographicevaluation of mandibular ridge resorption was conducted, and statistical analysis was performed using correlation and regression analysis. Results The study found a statistically significant positive correlation between BMI and mandibular ridge resorption in denture-wearing subjects, with a p-value of 0.039. A slight negative correlation was observed in non-denture wearers, with a p-value of 0.122. Overall, a significant relationship was found between BMI and mandibular ridge resorption, with a p-value of 0.007. Conclusion The study highlights the importance of considering BMI as a factor in mandibular ridge resorption in post-menopausal denture-wearing females. The findings suggest that prosthodontists should aim to preserve the residual ridge by using techniques such as broad area coverage, reduced denture teeth, and optimal occlusal tooth design.

Gallein increases prostaglandin F2α‑induced osteoprotegerin and IL‑6 secretion in osteoblasts.

Gallein is a known Gβγ subunit inhibitor, but its function in bone metabolism, especially in osteoblasts, and its molecular mechanism remains to be elucidated. Osteoprotegerin (OPG), which is secreted from osteoblasts, binds to nuclear factor kB receptor activator (RANK) ligand (RANKL) as a decoy receptor, prevents RANKL-RANK binding, and inhibits bone resorption. IL-6 is not only a bone resorption factor but also as a bone metabolism regulator. Prostaglandin F2α (PGF2α) promotes p44/p42 MAPK, p38 MAPK and stress-activated protein kinase/JNK phosphorylation in osteoblast-like MC3T3-E1 cells. In MC3T3-E1 cells, activated p44/p42 and p38 MAPKs promote IL-6 secretion and activated p44/p42 and p38 MAPKs and JNK promote OPG secretion. The present study aimed to investigate the effect and mechanism of gallein on PGF2α-induced OPG and IL-6 secretion using an osteoblastic MC3T3-E1 cell line. It was found that gallein significantly increased PGF2α-induced OPG and IL-6 secretion in the MC3T3-E1 cell. By contrast, fluorescein, which is a gallein-like compound that does not bind to Gβγ, did not affect PGF2α-induced OPG and IL-6 secretion. Gallein significantly improved the PGF2α-induced OPG and IL-6 mRNA expression levels. Gallein did not affect the PGF2α-activated phosphorylation of p44/p42 and p38 MAPKs and JNK. Gallein increased PGF2α-induced OPG and IL-6 secretion in osteoblasts, indicating that gallein may regulate bone remodeling via OPG/IL-6 in bone metabolism.

Bone microstructural characteristics or positional changes of condyle head affect short-term condyle head resorption after orthognathic surgery

Condylar resorption occurs in some cases after orthognathic surgery, and the risk factors associated with postoperative condylar head resorption have been extensively described. Nevertheless, even in cases with a combination of risk factors, postoperative condylar resorption may not appear. This study analyzed the microstructure and three-dimensional positional change of the condylar bone via imaging in patients who have undergone bimaxillary orthognathic surgery to determine whether the microstructure or condylar position differs between patients with and without postoperative condylar resorption. Among asymptomatic patients who underwent bimaxillary surgery between April 2021 and March 2022 at our department, 17 patients were analyzed, limited to “female,” “skeletal Class II,” and “high-angle cases,” which are known risk factors for mandibular head resorption. Multidetector computed tomography was performed on these patients before and 6 months after surgery, and the bone microstructure of the condylar head and the three-dimensional positional changes of the condylar bone and the proximal bony fragments were compared with the presence of postoperative condyle resorption using the bone morphology software TRI/3D-BON. Patients with condylar bone abnormalities before surgery and those with high trabecular bone density can develop postoperative resorption if the condyle is misaligned by surgery.

Hecogenin alleviates LPS-induced osteolysis via regulating pyroptosis and ROS involved Nrf2 activation

Reactive oxidative species (ROS) generation triggers pyroptosis and induces development of inflammatory osteolysis. Hecogenin (HG) has anti-inflammatory and antioxidative property, but its effects on inflammatory osteolysis remains unclear. In our study, we investigated the mechanism of HG on pyroptosis and its effect on inflammatory osteolysis in vitro and in vivo. The impact of HG on osteoclastogenesis was evaluated using cytotoxicity, TRAcP staining and bone resorption assays. The RNA-sequencing was employed to identify potential signaling pathways, and then RT-qPCR, western blot, immunofluorescence, and ELISA were used to verify. To determine the protective effect of HG in vivo, Lipopolysaccharide (LPS)-induced animal models were utilized, along with micro-CT and histological examination. HG suppressed RANKL-induced osteoclast differentiation, bone resorption, NFATc1 activity and downstream factors. RNA-sequencing results showed that HG inhibited osteoclastogenesis by modulating the inflammatory response and macrophage polarization. Furthermore, HG inhibited the NF-κB pathway, and deactivated the NLRP3 inflammasome. HG activated the expression of nuclear factor E2-related factor 2 (Nrf2) to eliminate ROS generation. Importantly, the inhibitory effect of HG on NLRP3 inflammasome could be reversed by treatment with the Nrf2 inhibitor ML385. In vivo, HG prevented the mice against LPS-induced osteolysis by suppressing osteoclastogenesis and inflammatory factors. In conclusion, HG could activate Nrf2 to eliminate ROS generation, inactivate NLRP3 inflammasome and inhibit pyroptosis, thereby suppressing osteoclastogenesis in vitro and alleviating inflammatory osteolysis in vivo, which indicating that HG might be a promising candidate to treat inflammatory osteolysis.

Reliability of information in YouTube™ videos on types of root resorption and related stimulating factors.

Root resorption occurs for various reasons and can also be seen as a treatment complication in orthodontics. This study aimed to assess the reliability and quality of YouTube™ videos on root resorption and to assess whether the videos referred to orthodontic treatment and other stimulation factors. YouTube was searched using the keyword 'root resorption', which is the most searched term on Google Trends. The first 200 videos identified using the default filter 'sort by relevance' were used. Information such as the source, type, duration, and number of likes were recorded. Videos were analyzed using a 23-point content scale related to root resorption and divided into groups (poor, moderate, and excellent) based on the Global Quality Score. A total of 95 videos were included in the study. Most were uploaded by dentists or dental clinics (n = 64, 67.4%). The mean number of days since upload was 1536 ± 1254, and the mean duration was 5 ± 4 min. The videos had a mean of 80 ± 515 likes and 7043 ± 35,382 views, and a mean viewing rate of 1131.71 ± 8736.83. The most discussed topic was radiographic signs of root resorption. While the highest content score for the videos was 21, the average score was only 4. The mean GQS was 2 ± 1. Grouping videos by GQS showed that 55 (57.9%) were poor, 38 (40%) were moderate, and 2 (2.1%) were excellent. There was a significant relationship between videos that mentioned orthodontics (n = 62; 65.3%) and higher GQS (p = .036), and a significant difference was between GQS groups for total content levels (p < .001). YouTube videos related to root resorption lack sufficient information and clarity, and their quality needs to be improved. Oral health professionals should strive to produce higher-quality videos.

Anti-osteoporosis effect of Prunus humilis fruit on ovariectomized rats via modulating the function of bone metabolism

Prunus humilis Bge. (PH), also known as calcium fruits, is rich in minerals and polyphenols. Given its high content of calcium and other mineral elements, it is believed to be an ideal health fruit to prevent osteoporosis (OP). Hence, the present research aimed to estimate the anti-osteoporotic activity of the fruit of PH in ovariectomized (OVX) rats and to explore the corresponding mechanisms. By utilizing LC-QTOF-MS/MS, 18 primary components, including 14 flavonoids and 4 phospholipids were elucidated in PH. The results of inductively coupled plasma optical emission spectrometry demonstrated that PH exhibited high levels of calcium (1573–1829 mg/kg), phosphorus (1328–1731 mg/kg), and magnesium (897–1027 mg/kg). The pharmacodynamic experiments conducted on OVX rats revealed that continuous oral intervention with PH (10–62.5 mg/kg/day) for three months resulted in significant improvements in both bone mineral density and bone microarchitecture. Meanwhile, the intervention with PH also effectively reversed the bone resorption and formation factors, including type I collagen carboxy-terminal peptide, acid phosphatase 5 tartrate-resistant, deoxypyridinoline, alkaline phosphatase, and procollagen amino-terminal peptide. Additionally, the utilization of LC-QTOF-MS/MS metabolomics revealed the identification of 16 differential metabolites linked to 9 metabolic pathways, all of which were recovered following PH treatment. Furthermore, the protein levels of β-catenin, Wnt1, Sirt1, and FOXO3a were significantly up-regulated after PH intervention, indicating a potential association between the anti-osteoporosis properties of PH and the Wnt/β-catenin and Sirt1/FOXO3a signaling pathways. Our findings provide a new idea for the prevention and treatment of OP through the daily consumption of PH, a sweet and flavorful fruit.

Prognostic risk factors for apical root resorption in orthodontic patients – Are the Kjær’s morphologic characteristics of clinical relevance?

BackgroundPatients undergoing orthodontic treatment (OT) face an increased risk of developing external apical root resorption (EARR). A prognostic risk assessment prior to OT can potentially be conducted through anatomical features in panoramic radiography. This retrospective study aimed to assess the significance of Kjær's morphological characteristics in analyzing the risk of EARR. MethodsPanoramic radiographs of 1,156 patients (624 females, 532 males) were retrospectively analyzed. Anamnestic and treatment-related data were extracted from patient records. The mean age at the start of OT was 12.8 ± 2.2 years (min. 6.4 years, max. 22.3 years) and at the end of OT 15.9 years (min. 8.5 years, max. 24.1 years). The mean treatment duration was 3.1 ± 1.6 years. Panoramic radiographs with a minimum of two per patient were examined for the presence of Kjær’s characteristics. The degree of EARR was registered defining resorption in four degrees of severity. Bivariate analysis and multivariate Poisson regression were performed to assess the association between Kjær’s characteristics and EARR patient- and tooth- related (α = 0.05). ResultsIn total, 72.8% of the patients showed EARR at the end of OT with lateral maxillary incisors most frequently affected. Short roots (p < 0.001) were significantly associated with EARR in patients. Tooth-related microdontia (#12, #22, lower second premolars), narrow crowns (#11, #21, lower incisors), short roots (upper incisors, lower first molars) and ectopia (#11, #21, #13), such as shorter distal roots of the mandibular first molar showed a significant association with EARR depending on severity degree. The type of orthodontic appliance (fixed: p < 0.001, fixed and removeable: p = 0.008), as well as treatment duration (p < 0.001) were also identified as risk factors for EARR. ConclusionsAlthough the risk assessment for EARR development through panoramic radiography analysis is limited, predisposition appears to be present in specific dental characteristics and treatment-related factors.

Genus_Ruminococcus and order_Burkholderiales affect osteoporosis by regulating the microbiota-gut-bone axis.

This study aimed to clarify the relationship between the gut microbiota and osteoporosis combining Mendelian randomization (MR) analysis with animal experiments. We conducted an analysis on the relationship between differential bacteria and osteoporosis using open-access genome-wide association study (GWAS) data on gut microbe and osteoporosis obtained from public databases. The analysis was performed using two-sample MR analysis, and the causal relationship was examined through inverse variance weighting (IVW), MR Egger, weighted median, and weighted mode methods. Bilateral oophorectomy was employed to replicate the mouse osteoporosis model, which was assessed by micro computed tomography (CT), pathological tests, and bone transformation indexes. Additionally, 16S rDNA sequencing was conducted on fecal samples, while SIgA and indexes of IL-6, IL-1β, and TNF-α inflammatory factors were examined in colon samples. Through immunofluorescence and histopathology, expression levels of tight junction proteins, such as claudin-1, ZO-1, and occludin, were assessed, and conduct correlation analysis on differential bacteria and related environmental factors were performed. A positive correlation was observed between g_Ruminococcus1 and the risk of osteoporosis, while O_Burkholderiales showed a negative correlation with the risk of osteoporosis. Furthermore, there was no evidence of heterogeneity or pleiotropy. The successful replication of the mouse osteoporosis model was assessed, and it was found that the abundance of the O_Burkholderiales was significantly reduced, while the abundance of g_Ruminococcus was significantly increased in the ovariectomized (OVX)-mice. The intestinal SIgA level of OVX mice decreased, the expression level of inflammatory factors increased, barrier damage occurred, and the content of LPS in the colon and serum significantly increased. The abundance level of O_Burkholderiales is strongly positively correlated with bone formation factors, gut barrier indicators, bone density, bone volume fraction, and trabecular bone quantity, whereas it was strongly negatively correlated with bone resorption factors and intestinal inflammatory factors, The abundance level of g_Ruminococcus shows a strong negative correlation with bone formation factors, gut barrier indicators, and bone volume fraction, and a strong positive correlation with bone resorption factors and intestinal inflammatory factors. O_Burkholderiales and g_Ruminococcus may regulate the development of osteoporosis through the microbiota-gut-bone axis.

Do erupting maxillary canines resorb adjacent teeth? A study focusing both on the ipsilateral and contralateral sides among individuals with unilaterally impacted canines.

To determine the prevalence of root resorption of teeth adjacent to permanent maxillary canines on both sides, by cone-beam computed tomography (CBCT), in pretreatment adolescent subjects with unilaterally impacted maxillary canines, and to define predictive factors for the root resorption. This retrospective sample included 76 adolescents (38 boys, 38 girls, mean age 12.3 ± 2.1 years; range 8-17 years) who had CBCT after detection of a unilateral impacted maxillary canine before any active orthodontic treatment. Both ipsilateral and contralateral sides were examined, and 14 qualitative and quantitative variables were collected. Descriptive statistics were calculated, and multiple logistic regression was used to predict root resorption. On the impaction side, 57.9% of canines resorbed at least one adjacent tooth compared with 13.2% on the contralateral side (P < .001). On the impaction side, resorption was slight in 59.6%, moderate in 5.8%, and severe in 34.6% of the cases. On the contralateral side, resorption was slight in 91.7%, moderate in 0%, and severe in 8.3% of the cases. On both sides, upper lateral incisors were the teeth most frequently resorbed, followed by the upper first premolars and upper central incisors. The presence of contact between the canine and the adjacent roots was the only statistically significant risk factor for resorption for both ipsilateral and contralateral sides. Orthodontists should look for root resorption on both sides in cases of unilaterally impacted maxillary canines.

Excessive Heat Generation by Power-Driven Craniotomy Tools: A Possible Cause of Autologous Bone Flap Resorption Observed in an Ex Vivo Simulation

Bone flap resorption is an issue after autologous cranioplasty. Critical temperatures above 50°C generated by power-driven craniotomy tools may lead to thermal osteonecrosis, a possible factor in resorption. This exvivo study examined whether the tools produced excessive heat resulting in bone flap resorption. Using swine scapulae maintained at body temperature, burr holes, straight and curved cuts, and wire-pass holes were made with power-driven craniotomy tools. Drilling was at the conventional feed rate (FR) plus irrigation (FR-I+), at a high FR plus irrigation (hFR-I+), and at high FR without irrigation (hFR-I-). The temperature in each trial was recorded by an infrared thermographic camera. With FR-I+, the maximum temperature at the burr holes, the cuts, and the wire-pass holes was 69.0°C, 56.7°C, and 46.2°C, respectively. With hFR-I+, these temperatures were 53.1°C, 52.1°C, and 46.0°C, with hFR-I- they were 56.0°C, 66.5°C, and 50.0°C; hFR-I- burr hole- and cutting procedures resulted in the highest incidence of bone temperatures above 50°C followed by FR-I+, and hFR-I+. At the site of wire-pass holes, only hFR-I- drilling produced this temperature. Except during prolonged procedures in thick bones, most drilling with irrigation did not reach the critical temperature. Drilling without irrigation risked generating the critical temperature. Knowing those characteristics may be a help to perform craniotomy with less thermal bone damage.

Full life cycle changes of low impacted mandibular third molar associated cystic lesions and adjacent tooth root resorption: a retrospective study

ObjectiveLow impacted third molars are usually asymptomatic and are often found by X-ray examination. The removal of asymptomatic low impacted third molars is one of the most controversial clinical issues in oral and maxillofacial surgery.MethodsIn this study, 806 patients with low impacted mandibular third molars (LIMTMs) (full bony impaction) were analyzed to determine the prevalence and risk factors for cystic lesions and adjacent tooth root resorption throughout the patients’ entire life cycle.ResultsThe results showed that the prevalence of adjacent tooth root resorption and cystic lesions was age-related, exhibiting a trend of first increasing and then decreasing; prevalence peaked at the age of 41 to 45 years old, the prevalence rates were 12.50% and 11.11% respectively. And the lowest prevalence rate was 2.86% and 2.44% in ≥ 61 group and 56- to 60-year age group respectively. Age was an independent risk factor for adjacent tooth root resorption of LIMTMs, whereas age and impaction type (especially inverted impaction) were independent risk factors for cystic lesions.ConclusionsThe full life cycle management strategy for LIMTMs may need to be individualized. Surgical removal is recommended for LIMTMs in patients younger than 41 to 45 years, especially for inverted, mesioangular, and horizontally impacted LIMTMs. LIMTMs in patients older than 41 to 45 years may be treated conservatively with regular follow-up, but surgical removal of inverted impacted LIMTMs is still recommended to avoid cyst formation.

Risk Factors for Resorption of Lateral Incisors by Impacted Maxillary Canines: Systematic Review

Risk Factors for Resorption of Lateral Incisors by Impacted Maxillary Canines: Systematic Review

Infectious and inflammatory factor of resorption of peri-implant tissues. Literature review

Today, in clinical practice, the loss of marginal bone mass around dental implants in the early stages after the installation and opening of the implant is increasingly common. Early clinical publications suggested that this bone loss occurred during the first year of prosthetics. Thus, numerous attempts have been made to minimize or eliminate such bone loss. However, the timing and cause of bone loss are not always obvious. The purpose of this review was to analyze data on marginal bone loss around dental implants in terms of biological implications to help understand changes in marginal bone around dental implants. One hypothesis for bone loss around dental implants has been related with infected interface between the implant and abutment. This review article shows that bone loss of 1.5 to 2.0 mm occurred around implant-abutment junctions at the bone level. The bone loss level was correlated with implant-abatement interface size. Recent publications indicate that such dental implant systems with large prosthetic-implant gaps may cause peri-implantitis with further implant loss.

Resorptions and orthodontics

It's generally accepted that one of the risks associated with orthodontic treatment is apical root resorption, even though this may occur outside orthodontic treatment. In any case, it causes root shortening. Orthodontists are probably the only dental surgeons who use the inflammatory process as a therapeutic tool. They need to be aware of the risk factors for root inflammation. Along with recurrence, leukemia and periodontal problems, resorption is one of the "inconveniences" of orthodontics, which, if not inevitable, must at least be minimized. At present, the orthodontic literature on root resorption provides some clues as to the factors associated with the onset, severity and management of root resorption, although the complexity of this phenomenon does not allow us to arrive at a clear and unequivocal consensus. For this reason, it is important to identify potential risk factors for resorption, to take them into account before/during and after treatment, and to know what attitude to adopt in the event of resorption appearing, all in order to minimize this phenomenon, as everyone agrees that it can be a source of harm and stress for both patient and practitioner. There are still many grey areas in our understanding of the phenomenon, including how the elements of orthodontic treatment influence orthodontic resorption. Irreversible in nature, resorption can be sufficiently extensive to cast doubt on the benefit of successful orthodontic treatment.

The prevalence, characteristics, and risk factors of external cervical resorption: a retrospective practice-based study.

External cervical root resorption (ECR) is a poorly understood and aggressive form of resorption. The purpose of this study was to examine the prevalence, characteristics, and risk factors associated with the occurrence of ECR in patients seeking endodontic care from private practice settings. Records of 343 patients with 390 teeth diagnosed with ECR were identified from 3 private endodontic practices from 2008 to 2022. The patients' demographic information, systemic conditions, and dental history were recorded. The characteristics of the cases including Heithersay classification, pulpal and periapical status, and their management were documented. The association between case severity and potential predisposing factors was examined using chi-square analysis. The overall prevalence of ECR among patients seeking endodontic care was low (< 1%). However, there was a greater than twofold increase in the pooled prevalence from 2016 to 2021 (0.99%) compared to the data from 2010 to 2015 (0.46%). The most commonly affected teeth were anterior teeth (48.7%). Class II (30.0%) and class III (45.4%) defects were the most often identified. Patients with a history of trauma or orthodontic treatment were significantly more likely to be diagnosed with severe cervical resorption (class III or IV) (p < 0.05). There has been an increase in the prevalence of ECR in patients seeking endodontic care. A history of orthodontic treatment and traumatic dental mechanical injuries may predict the severity of resorption. The upward trend in the occurrence of ECR warrants close monitoring of the patients at high risk of developing the condition to facilitate early detection and management.

ASPECTS OF ETIOLOGY, DIAGNOSIS AND TREATMENT OF PREERUPTIVE INTRACORONAL RESORPTION IN CHILDREN (LITERATURE REVIEW)

The purpose of this work was to study the literature on research papers by domestic and foreign authors describing pre-eruption intracoronal resorption. The review discusses issues that indicate the presence of a resorption process in permanent teeth before their eruption. This lesion of the hard tissues of the teeth is rare, and the etiology of this process is not fully understood. The processes of tooth resorption can be observed outside on the root surface or inside the pulp chamber, and if a permanent tooth is involved in this process, this indicates the development of pathological resorption. Along with dental caries and periodontal disease in childhood, processes of resorption of coronal dentin tissue in unerupted permanent teeth can be observed. Some authors describe internal resorption, ectopic positioning, external resorption, and origin from developmental pits on the occlusal surface as etiological factors for preeruptive intracoronal resorption, but other authors suggest that the etiology of this lesion remains poorly understood. The main diagnostic method is an x-ray examination, in which preeruptive intracoronal resorption is accidentally detected and other research methods are additionally used. Histological examination reveals osteoclasts, multinucleated giant cells, macrophages, and serrated edges in this lesion, which may possibly enter the developing tooth from the surrounding bone or through breaks in the dental follicle or enamel epithelium. With a small lesion and if the tooth is close to eruption, periodic X-ray control is necessary, and after eruption, when occlusal access is reached, the defect is restored in order to minimize the attachment of the carious process.

Imagem radiolucente em terceiro molar inferior: cárie oculta ou reabsorção pré-eruptiva?: um relato de caso

ABSTRACT Caries is a multifactorial disease due to the imbalance of the de/re-mineralization process. Complementary radiographic examinations are able to detect hidden caries. The purpose of this short communication was to investigate the radiolucent image suggestive of hidden caries in lower third molar. The extraction of the tooth, decalcification, inclusion and preparation were performed for histological analysis of the lesion. Histological findings revealed a pre-eruptive resorption, and the etiological factors of this coronary resorption were undefined. The professional should be aware of the occurrences of these lesions to early diagnose and propose appropriate treatment to avoid future complications to the patient.

Evaluation of the impacted maxillary canines position, determination of the possible indicators of the impaction difficulty and the risk factors for adjacent teeth root resorption

Background/Aim. An impacted tooth is a tooth that could not erupt and take its place in the dental row. Impacted maxillary canines are a very frequent problem in orthodontic practices. They are the second most impacted teeth, right after the third molars. The aim of this cross-sectional study was to evaluate the two-dimensional and three-dimensional position of the impacted maxillary canines and make a descriptive study analysis of possible indicators of the impaction difficulty and risk factors for adjacent tooth root resorption. Methods. In this study, 94 subjects with 116 diagnosed maxillary canine impaction were included. The two-dimensional position of the impacted canines (IC) was evaluated on the panoramic projection of the cone beam computed tomography (CBCT) images. Canine position (CP) to the X, Y, and Z-axis was measured and scored using the novel classification system that incorporates three-dimensional information of CBCT imaging ? the KPG index. Based on the KPG index value, impaction was defined as easy, moderate, difficult, and extremely difficult. In order to determine indicators of impaction difficulty and risk factors of root resorption of adjacent teeth, qualitative variables (gender, side of impaction, etc.) and quantitative variables [age, canine distance to the occlusal plane (OccP), etc.] were tested with multiple logistic regression. Results. The mean age of the sub-jects was 19.8 ? 5.2 years. The impactions were twice as prevalent in females compared to males. Most (71.4%) impactions were unilateral in palatal position of the canines. Adjacent root resorption was present in 27.3% of cases of impaction, and the central incisor was mostly affected. More than half of the impactions were of moderate level. In univariable analysis, canine distance to sagittal medial line (SML), angle between canine and SML, OccP, and first premolar, respectively, were significant in impaction difficulty prediction. Multivariable analysis showed that angle between canine and the first premolar could be a risk factor for adjacent root resorption. Conclusion. Most impacted maxillary canines were in the palatal position, with a KPG index value of moderate difficulty. Besides the position to the OccP and SML, angle between canine and the first premolar should be estimated, as a part of diagnostic procedures, to evaluate the risk of adjacent root resorption, prevent resorption, and decide on the treatment plan.