Effects of Cinnamoyloxy-mammeisin from Geopropolis on Osteoclast Differentiation and Porphyromonas gingivalis-Induced Periodontitis.

Bone-loss-related diseases such as rheumatoid arthritis, osteomyelitis, osteoporosis, and periodontitis are associated with high rates of morbidity worldwide. These disorders are characterized by an imbalance between the formation and activity of osteoblasts and osteoclasts, leading to bone loss. In this context, we evaluated the effect of cinnamoyloxy-mammeisin (CNM), an anti-inflammatory coumarin found in Melipona scutellaris geopropolis, on key targets related to bone remodeling. In the present study we investigated the in vitro effects of CNM on osteoclast differentiation and M-CSF+RANKL-induced osteoclastogenic marker expression. Additionally, the interference of CNM treatment on osteoclast activity was evaluated by zymography and resorption area. Finally, we assessed the capacity of the compound to mitigate alveolar bone loss in vivo in experimental murine periodontitis induced by Porphyromonas gingivalis. We observed that treatment with CNM impaired osteoclast differentiation, as evidenced by a reduced number of tartrate-resistant acid-phosphatase-positive multinucleated cells (TRAP+) as well as the expression of osteoclastogenic markers upon M-CSF+RANKL-induced stimulation. Similarly, we observed reduced gelatinolytic and resorption capacity in M-CSF+RANKL-induced cells in vitro. Lastly, CNM attenuated alveolar bone loss in an experimental murine periodontitis model. These findings indicate that CNM may be considered a promising treatment for bone loss diseases.

Treatment of Medication-Related Osteonecrosis of the Jaws without Segmental Resections: A Case Series.

BACKGROUND Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious reaction to anti-resorptive drugs (ARDs) in patients treated for osteoporosis and conditions related to cancer. Treatment for MRONJ consists of the use of non-operative therapies according to the evolution of the disease, which consist of the use of antimicrobial mouthwashes, systemic antibiotics, and operative therapies, such as debridement of necrotic bone, marginal or segmental resection, and bone reconstruction of the jaws in more advanced stages of the disease. CASE REPORT This is a case series of 11 female patients treated for MRONJ, with a mean age of 76.5 years. Patients with malignant diseases of the jaws or those undergoing head and neck radiotherapy were excluded. Nine patients were medicated for osteoporosis with oral bisphosphonates and denosumab, and 2 patients used zoledronate to treat metastatic breast cancer. MRONJ prevailed in the mandible, most patients were classified as stage 2, and the most frequent triggers were tooth extraction and prosthetic trauma. All patients initially underwent non-operative therapies and were operated according to MRONJ stage, but none required segmental resection. Adjuvant treatments were used in 5 patients, and mean treatment and follow-up periods were 5 and 18.3 months, respectively. There was complete resolution of disease in all patients, with only 1 relapse. CONCLUSIONS This case series suggests that it is possible to treat MRONJ with conservative therapies in the early stages of the disease and minimally invasive surgeries in more advanced stages of the disease, thus avoiding segmental jaw resections.

A Case Report of Oral Bisphosphonate Treatment for Osteoporosis Leading to Atypical Femoral Fracture and Pathologic Mandibular Fracture.

BACKGROUND Bisphosphonates inhibit bone resorption in patients with postmenopausal osteoporosis and reduce osteoporotic fracture incidence. Medication-related osteonecrosis of the jaws (MRONJ) and atypical femoral fractures (AFF) are both rare but serious adverse effects of anti-resorptive drugs (ARD) such as bisphosphonates. The most advanced form of MRONJ is termed stage 3 and can lead to severe local sequelae like pathologic mandibular fractures (PMF). This study reports a case of MRONJ-related PMF and AFF with osteomyelitis secondary to bisphosphonate treatment for osteoporosis. CASE REPORT A 63-year-old white woman was diagnosed with PMF related to MRONJ stage 3 during treatment of an AFF with osteomyelitis. She had been treated for postmenopausal osteoporosis with 70 mg of alendronate weekly for 2 years. The PMF was treated by stable internal fixation combined with debridement and sequestrectomy, but further debridement was required and 2 mandibular implants were then removed. Postoperative recovery was uneventful and the mandibular infection was controlled after the second surgery. Three weeks later, she was discharged from the hospital, instructed to discontinue the use of alendronate, and referred for 30 sessions of hyperbaric oxygen therapy. At the 3-year follow-up, the PMF was completely healed without signs of mandibular infection or bone exposure. CONCLUSIONS This report raises awareness of both MRONJ and AFF as possible adverse effects of short-term bisphosphonate therapy for postmenopausal osteoporosis, and highlights the importance of dental and orthopedic follow-ups. It is crucial to emphasize the need for early diagnosis and treatment to prevent MRONJ progression to PMF.

Performance of panoramic radiography compared with computed tomography in the evaluation of pathological changes in the maxillary sinuses: a systematic review and meta-analysis.

OBJECTIVE: A systematic review was performed to evaluate the performance of panoramic radiography (PR) vs CT or cone beam CT (CBCT) in the diagnosis of pathological maxillary sinuses. METHODS: This review was registered in the PROSPERO database under the number CRD42020211766. Observational studies that compared PR with CT/CBCT were used to evaluate pathological changes in the maxillary sinuses. A complete search of seven primary databases and gray literature was carried out. The risk of bias was assessed according to the Newcastle-Ottawa tool, and the GRADE tool was used to assess the quality of evidence. A binary meta-analysis was performed to assess the effectiveness of evaluating pathological alterations in the maxillary sinuses in PR and CT/CBCT. RESULTS: Seven studies were included in our study, out of which four were included in a quantitative analysis. All studies were classified as low risk of bias. Five studies compared PR with CBCT and two studies compared PR to CT. The most common pathological alteration in maxillary sinuses reported was mucosal thickening. CT/CBCT was seen to be the most effective method for assessing pathological changes in the maxillary sinus when compared to PR (RR = 0.19, 95% confidence interval [CI] = 0.05 to 0.70, p = 0.01). CONCLUSION: CT/CBCT are the most appropriate imaging methods to evaluate pathological changes in the maxillary sinuses, while PR is still limited in the evaluation of these changes being considered only for initial diagnosis.

Do elderly edentulous patients with a history of periodontitis harbor periodontal pathogens?

OBJECTIVES: The presence of periodontal pathogens in the oral cavity may impact implant survival. Therefore, this study aimed to determine the prevalence of Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Tannerella forsythia, Treponema denticola, Eikenella corrodens, and Parvimonas micra in a specific elderly population with a history of periodontitis who have never worn dentures. MATERIAL AND METHODS: Thirty dentate subjects (mean age 61.7 +/- 7.05 years) and 30 edentulous subjects (mean age 65.8 +/- 8.05 years) were included in this cross-sectional study. Microbiological samples of cheek mucosa and the dorsum of the tongue were taken from all subjects. In addition, sulcus samples were taken from the dentate group. All samples were analysed using a bacterial DNA-specific polymerase chain reaction. RESULTS: All the pathogens studied were detected in dentate and edentulous subjects. When cheek and tongue samples were combined, C. rectus, A. actinomycetemcomitans and E. corrodens presented with a similar prevalence in both groups, whereas the other species were more prevalent specifically in the dentate group (P<0.05). In dentate subjects, P. intermedia and T. denticola were present in higher frequencies in the cheek mucosa (26.67% and 66.67%, respectively), whereas P. gingivalis and T. forsythia were more prevalent in the tongue samples (26.67% and 56.67%, respectively). CONCLUSIONS: Periodontal pathogens may persist in the oral cavity of edentulous subjects who have had periodontal disease, even 1 year after the extraction of all teeth and in the absence of other hard surfaces in the mouth.

Effect of pentoxifylline and α-tocopherol on medication-related osteonecrosis of the jaw in rats: Before and after dental extraction.

OBJECTIVE: Evaluate the effect of pentoxifylline and α-tocopherol administration in the prevention or treatment of medication-related jaw osteonecrosis (MRONJ). METHODOLOGY: Sixty Wistar rats were divided into three prevention (C-prev, BP-prev and BP/PT-prev) and three treatment groups (C-treat, BP-treat and BP/PT-treat), n = 10. The animals in the BP-prev, BP/PT-prev, BP-treat and BP/PT-treat groups received zoledronic acid (0.1 mg/kg) for 12 weeks, while the animals in the C-prev and C-treat groups received saline solution. At week 6, all animals underwent tooth extraction. Between week 5 and week 12, the BP/PT-prev group was treated with pentoxifylline (50 mg/kg/day) and α-tocopherol (80 mg/kg/day), with euthanasia at the end of week 12. The BP/PT-treat group received the same drug protocol, but it was performed between week 12 and week 16, with euthanasia at the end of week 16. Afterwards, the presence of osteonecrosis was evaluated by clinical analysis, radiographic and histological. RESULTS: BP/PT-treat group showed a reduction in the histological incidence of osteonecrosis by 50%, decrease the percentage of empty osteocyte gaps and the necrotic area, decrease the presence of bone sequestration and increase the number of osteocytes and alveolar blood flow (p < 0.05). However, BP/PT-prev group showed only a reduction in the necrotic area percentage when compared to BP-prev (p < 0.05). CONCLUSIONS: Pentoxifylline and α-tocopherol administration before tooth extraction was not effective in preventing MRONJ. However, this drug protocol was able to reduce MRONJ manifestation when administrate after discontinuation of bisphosphonate, thus it can be considered as a viable strategy for the treatment of this pathological condition.

Absence of medication-related jaw osteonecrosis after treatment with strontium ranelate in ovariectomized rats.

This study aimed to evaluate the potential of strontium ranelate (SR) in medication-related jaw osteonecrosis (MRONJ) after tooth extraction in ovariectomized rats. Thirty ovariectomized rats were divided into three groups (n = 10): bisphophonate (BP) group (zoledronic acid; 0.4 mg/kg/week), SR group (625 mg/kg/day), and control group (saline solution). The lower first molars were extracted after 60 days of drug therapy. Drug administration was continued for another 30 days after tooth extraction. The mandibles were subjected to clinical, histological, radiographic, and microtomographic evaluations. Only the BP group showed clinical changes, characterized by the presence of 70% (n = 7) and 20% (n = 2) of ulcers and extraoral fistulas. Radiographic evaluation demonstrated bone sequestration only in the BP group (n = 7, 70%). Microtomographic analysis revealed increased bone porosity after ovariectomy, particularly in the the control group (p < 0.05). The BP group showed a higher bone surface density, bone volume, and trabecular number than SR and control groups, but with less trabecular separation (p < 0.05). All the animals in the BP group demonstrated histological osteonecrosis. There was no evidence of osteonecrosis in the control and SR groups, which was characterized by the absence of empty osteocyte gaps and associated with the gradual healing of the extraction area. Also, an increased number of blood vessels and a reduced number of osteoclasts were observed in the SR group (p < 0.05). Therefore, SR treatment increased angiogenesis and osteoclastogenesis in the healing socket and was not associated with MRONJ development after tooth extraction in ovariectomized rats.

Caloric restriction prevents alveolar bone loss in the experimental periodontitis in obese rats.

AIMS: It has been shown that periodontitis, can be modified by systemic changes, including behavioral factors, such as diet. Caloric restriction is one of the dietary therapeutic strategies indicated for obesity. It is associated with several benefits, among them, modulation of the inflammatory response. The aim of this study was to verify whether caloric restriction in obese rats changes the progression of experimental ligature-induced periodontitis. MATERIALS AND METHODS: Forty-eight Wistar rats were used for 24 weeks and initially fed with cafeteria diet during 12 weeks. The animals were divided into four groups according to the caloric restriction and experimental periodontitis. The cotton thread was placed around the mandibular first molars, for 15 days, before the end of the experiment. Rats submitted to caloric restriction received, from the 13th week of the experimental protocol, 70% of the food intake compared to the ad libitum animals of other study of the our research group. Alveolar bone loss was assessed using macroscopic morphometric analysis. Analyzes of clinical periodontal measures, biometrics, serum biomarkers and biochemical parameters were performed. KEY FINDINGS: Caloric restriction decreased the alveolar bone loss in the periodontitis group when compared to the group that received a cafeteria diet with periodontitis. Moreover, the results demonstrate the improvement in the glycemic profile, without prejudice to bone tissue biomarkers. SIGNIFICANCE: Based on the results, caloric restriction reduces the progression of alveolar bone loss in rats with experimental periodontitis, in addition to presenting benefits in biometric data, decreasing both glycemic profile and clinical periodontal measures.

Psychological stress has no association with salivary levels of ß-defensin 2 and ß-defensin 3.

BACKGROUND: Recent studies suggest that stress can predispose an individual to the development of periodontal disease, but the exact biological mechanism is unknown. Considering that psychological stress can down-regulate the production of ß-defensins (antimicrobial peptides produced in the oral cavity), the aim of the present study was to evaluate the association between stress and salivary levels of ß-defensin 2 (HBD-2) and ß-defensin 3 (HBD-3). METHODS: For this purpose, seventy five volunteers, classified as periodontally healthy, were submitted to a psychological evaluation using a validated questionnaire (Questionnaire of Lipp-ISS). Following analysis of the questionnaires, the subjects were divided in two groups (Group A: Absence of stress and Group B: Presence of stress). Unstimulated saliva samples were collected and the concentration of total protein was determined using the BCA method, and the concentrations of HBD-2 and HBD-3 were determined by ELISA. RESULTS: The levels of total protein did not show a statistically significant difference between the groups. Analyses of HBD-2 and HBD-3 concentrations indicate that the stress condition was not associated with the levels of either peptide in saliva (P=0.3664 for HBD-2 and P=0.3608 for HBD-3). CONCLUSION: In periodontally healthy subjects, HBD-2 and HBD-3 levels are not influenced by stress.

Gingival overgrowth in subjects under immunosuppressive regimens based on cyclosporine, tacrolimus, or sirolimus.

AIM: To assess the prevalence and variables associated with gingival overgrowth (GO) in renal transplant recipients medicated with cyclosporine (CsA), tacrolimus (Tcr), or sirolimus (Sir). MATERIALS AND METHODS: One hundred and thirty-five eligible subjects were divided in CsA, Tcr, and Sir groups comprising 45 subjects each. GO was visually assessed and subjects were assigned as GO+ or GO- in a post hoc definition. Saliva samples were collected and the presence of periodontal pathogens was assessed through polymerase chain reaction. Variables of interest were compared between GO+ and GO- subjects through univariate and multivariate analysis. RESULTS: Prevalence of GO was of 60.0% for CsA, 28.9% for Tcr, and 15.6% for Sir groups. Within the CsA group, GO was associated with papillary bleeding index (p=0.001); within the Tcr group, GO was associated with CsA previous use (p=0.013), and calcium channel blockers (CCB) use (p=0.003); within the Sir group, GO was associated with papillary bleeding index (p=0.018), and CCB use (p=0.020). A higher frequency of Tannerella forsythia was observed among GO+ subjects medicated with Tcr. CONCLUSION: Pharmacological and periodontal variables were associated with GO in different immunosuppressive regimens. Integration between the medical and the dental team may be an important approach in the post-transplant maintenance routine.

Do elderly edentulous patients with a history of periodontitis harbor periodontal pathogens?

OBJECTIVES: The presence of periodontal pathogens in the oral cavity may impact implant survival. Therefore, this study aimed to determine the prevalence of Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Tannerella forsythia, Treponema denticola, Eikenella corrodens and Parvimonas micra in a specific elderly population with a history of periodontitis who have never worn dentures. MATERIAL AND METHODS: Thirty dentate subjects (mean age 61.7+/-7.05 years) and 30 edentulous subjects (mean age 65.8+/-8.05 years) were included in this cross-sectional study. Microbiological samples of cheek mucosa and the dorsum of the tongue were taken from all subjects. In addition, sulcus samples were taken from the dentate group. All samples were analysed using a bacterial DNA-specific polymerase chain reaction. RESULTS: All the pathogens studied were detected in dentate and edentulous subjects. When cheek and tongue samples were combined, C. rectus, A. actinomycetemcomitans and E. corrodens presented with a similar prevalence in both groups, whereas the other species were more prevalent specifically in the dentate group (P<0.05). In dentate subjects, P. intermedia and T. denticola were present in higher frequencies in the cheek mucosa (26.67% and 66.67%, respectively), whereas P. gingivalis and T. forsythia were more prevalent in the tongue samples (26.67% and 56.67%, respectively). CONCLUSIONS: Periodontal pathogens may persist in the oral cavity of edentulous subjects who have had periodontal disease, even 1 year after the extraction of all teeth and in the absence of other hard surfaces in the mouth.

Diminished treatment response of periodontally diseased patients infected with the JP2 clone of Aggregatibacter (Actinobacillus) actinomycetemcomitans.

This longitudinal study evaluated the response to periodontal treatment by subjects infected with either JP2 (n = 25) or non-JP2 (n = 25) Aggregatibacter (Actinobacillus) actinomycetemcomitans. Participants were treated during the first 4 months by receiving (i) scaling and root planing, (ii) systemic antibiotic therapy, and (iii) periodontal surgery. Probing depth (PD), clinical attachment level (CAL), and gingival and plaque indices (GI and PI, respectively) were monitored at baseline and at 12 months, along with DNA-PCR-based subgingival detection of JP2 or non-JP2 A. actinomycetemcomitans. At baseline, PD, CAL, and GI scores were statistically higher in the JP2 strain-positive group than the non-JP2-strain-positive group. At 12 months, PD, CAL, and GI scores had decreased significantly for both groups, but the reduction rates of PD and CAL were higher in the non-JP2-strain-positive group. Among JP2-strain-positive patients in the baseline, patients who remained JP2 strain positive at 12 months showed significantly higher GIs than did the patients who had lost the detectable JP2 clone. Patients who remained JP2 strain positive at 12 months appeared to be more resistant to mechanical-chemical therapy than did those who were still non-JP2 strain positive, while the elimination of JP2 A. actinomycetemcomitans remarkably diminished gingival inflammation. Early identification and elimination of the JP2 clone of A. actinomycetemcomitans will enable practitioners to effectively predict the outcome of treatments applied to periodontal patients.

Essential oils in one-stage full-mouth disinfection: double-blind, randomized clinical trial of long-term clinical, microbial and salivary effects.

AIM: This randomized clinical trial evaluated the effects of an essential oils-containing mouthrinse for full-mouth disinfection. MATERIAL AND METHODS: Fifty patients were assigned to receive full-mouth disinfection with either essential oils or placebo. At baseline, 2 and 6 months of treatment the primary outcomes probing depth (PD), plaque index (PlI) and modified gingival index (MGI) were monitored. Additional monitoring included bacterial presence (by polymerase chain reaction) in subgingival, saliva and tongue samples; flows, pH, total protein and alkaline phosphatase salivary levels. The following statistics were used: ANOVA, Student's t-test, chi(2) and Kruskal-Wallis (p<0.05). RESULTS: Mean PD>or=3.5 mm was reduced over time in both the placebo and the test groups, but there was no difference in PD reduction between groups at 2 and 6 months. At 2 and 6 months, PlI and MGI showed greater reductions in the test group than in the placebo group. Porphyromona gingivalis was not reduced in any site. At 6 months, Campylobacter rectus increased in both groups, while Tannerella forsythensis decreased subgingivally in the test group. S. sanguinis increased, except subgingivally, in the placebo group. Salivary pH and flows were not altered. Total protein reduced only in the test group. Alkaline phosphatase did not change in either group. CONCLUSIONS: Essential oils for full-mouth disinfection showed clinical benefits, namely reducing plaque and gingival inflammation without altering basic salivary parameters.

Prevalência tomográfica de variações anatômicas no complexo nasossinusal em pacientes com sinusite não odontogênica / Tomographic prevalence of anatomical variations in the nasosinusal complex in patients with non-odontogenic sinusitis

Objetivo: O objetivo do estudo foi avaliar a prevalência de variações anatômicas no complexo nasossinusal por meio de tomografia computadorizada (TC) em pacientes com sinusite não odontogênica. Métodos: Um estudo observacional e retrospectivo consistiu em 860 prontuários com indicação de tomografias computadorizadas multislice para avaliação de sinusite. A sinusite odontogênica foi caracterizada pela presença de espessamento da mucosa sinusal maior que 2 milímetros e ausência de alterações dentárias na região. Posteriormente, foram avaliadas as variações do complexo nasossinusal e realizada uma análise descritiva. Em seguida, 33 tomografias computadorizadas foram analisadas com sinusopatia não odontogênica, e o complexo nasossinusal foi avaliado quanto à presença das seguintes variações anatômicas como desvio do septo nasal associado a esporão ósseo, concha média bolhos, aumento do seio frontal entre outras. Resultados: Variações anatômicas foram observadas em 87,9% dos casos, sendo 15 do gênero masculino (46,0%) e 18 do gênero feminino (54,0%) e distribuídos em 45,5% dos pacientes entre 41-60 anos. A variação anatômica mais frequente foi a concha média bolhosa (37,9%), seguida de septações no seio maxilar (10,3%) e seio frontal alargado (13,8%). Conclusão:Verificou-se uma considerável incidência de variações anatômicas associadas à sinusite não odontogênica, com evidência para a concha média bolhosa.

Aim: The aim of the study was to assess the prevalence of anatomical variations in the sinonasal complex using computed tomography (CT) in patients with non-odontogenic sinusitis. Methods: This observational and retrospective study involved the analysis of 860 multislice CT scans prescribed for sinusitis evaluation. Non-odontogenic sinusitis was characterized by the presence of sinus mucosal thickening exceeding 2 millimeters and the absence of dental changes in the region. Subsequently, sinonasal complex variations were evaluated, and a descriptive analysis was conducted. Subsequently, 33 CT scans with non-odontogenic sinusopathy were analyzed, and the sinonasal complex was evaluated for the presence of the following anatomical variations: deviation of the nasal septum associated with a bony spur, bullous middle concha, unilateral hypoplasia of the maxillary sinus, among others. Results: Anatomical variations were observed in 87.9% of cases, with 15 males (46.0%) and 18 female (54.0%), distributed among patients aged 41-60 years (45.5%). The most frequent anatomical variation was the bullous middle concha (37.9%), followed by septations in the maxillary sinus (10.3%) and enlarged frontal sinus (13.8%). Conclusion: A considerable incidence of anatomical variations associated with non-odontogenic sinusitis was observed, with evidence of a bullous middle concha.

Etiological analysis of initial colonization of periodontal pathogens in oral cavity.

It is unclear when the initial colonization by periodontal pathogens occurs in the oral cavity. Therefore, we report here the association between specific age groups and the time when the initial colonization by periodontal pathogens occurs in the oral cavity in such groups. Findings are based on an epidemiological analysis of the prevalence of five periodontal pathogens in the oral cavities of a wide range of age populations, from newborn to elderly, who were randomly selected in a geographic region of Brazil. These periodontal pathogens include Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Tannerella forsythia and were analyzed in the bacterial samples isolated from gingival sulcus, the dorsum of the tongue, and cheek mucosa of diverse age groups, using a bacterial DNA-specific PCR method. Results indicated that there are distinct age-related groups where initial colonization by the five periodontal pathogens examined in this study can be detected and that the presence of teeth is a permissive factor for colonization by P. gingivalis, P. intermedia, and T. forsythia. Although it remains unclear exactly how or when target pathogens colonize healthy subjects, an understanding of age-related groups does provide a potentially useful tool in the early detection and prevention of periodontitis in healthy individuals.

Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas / Prevalence of juxta-apical radiolucency and association/relations with the lower third molar in panoramic radiography

Objetivo: Avaliar a prevalência da radiolucência justa-apical (RJA) e sua relação com os terceiros molares inferiores, em 1054 radiografias panorâmicas. Métodos: A amostra foi constituída por radiografias panorâmicas digitais de indivíduos maiores de 18 anos, com pelo menos um terceiro molar inferior. As imagens foram analisadas para a presença de RJA em relação à corticalização, localização, relação com o canal mandibular, angulação e profundidade de impactação do terceiro molar. Os dados foram analisados através de estatística descritiva e pelo teste Qui-quadrado, sendo que valores de p < 0,05 foram considerados como significativos. Resultados:Foi encontrada uma prevalência de 2,75% de RJA, sendo predominante no sexo feminino (p = 0,01). A RJA foi visualizada em maior número corticalizada (58,63%), lateroapical (48,27%), em dentes parcialmente intraósseo (68,97%) e mesioangulados (55,17%). Em relação ao canal mandibular, houve maior prevalência na posição sobreposta ao canal mandibular (65,52%). Conclusão: A prevalência de RJA foi de 2,75% do total de 1054 radiografias panorâmicas avaliadas. Em relação ao canal mandibular, apresentou maior prevalência sobreposto. Além disso, a maior parte das RJA se apresentaram corticalizadas, em posição lateroapical, associada a dentes em posição mesioangular. Descritores: Radiografia panorâmica. Dente serotino. Nervo mandibular.Prevalência de radiolucência justa-apical e sua relação com terceiros molares inferiores em radiografias panorâmicas

Aim: To evaluate the prevalence of juxta-apical radiolucency (JAR) and its relationship with the lower third molars and adjacent structures, in 1,054 panoramic radiographs. Methods: The sample consisted of digital panoramic radiographs of individuals over 18 years of age, with at least one lower third molar. The images were analyzed for the presence of JAR in relation to corticalization, location, impaction depth, relationship with the mandibular canal, angulation, and impaction of the third molar. Data were analyzed using descriptive statistics and the chi-square test, and values of p < 0.05 were considered significant.Results: A prevalence of 2.75% of JAR was found, with a statistical difference between JAR and gender (p = 0.01), which proved to be predominant in females. The JAR was seen in greater numbers as corticalized (58.63%), lateroapical (48.27%), and mesioangulated (55.17%), as well as in erupted teeth (31.03%). In relation to the mandibular canal, it presented a higher prevalence when superimposed upon the mandibular canal (65.52%). Conclusions:The prevalence of RJA was 2.75% of the 1,054 evaluated panoramic radiographs. In relation to the mandibular canal, it presented a higher prevalence of superimposition. In addition, most of the RJA were corticalized, in a lateroapical position, associated with teeth in a mesioangular position. Uniterms: Panoramic radiography. Third molar. Mandibular nerve.

Influence of Adrenergic Neuromodulation during Induction of Periodontitis in Rats.

The action of the sympathetic nervous system in the control of bone remodeling and immunoinflammatory responses is the basis of the hypothesis that its modulation can influence the progress of periodontal disease. The aim of this study was to analyze the effects of the blockade and of the activation of ß-adrenergic receptors in periodontal disease in rats. Thirty-two rats were divided into four groups: 1) animals with induced periodontitis that received propranolol (a non-selective ß-adrenergic antagonist) 0.1 mg/kg (PRO); 2) animals with induced periodontitis that received isoproterenol (a non- selective ß-adrenergic agonist) 0.75 mg/kg (ISO); 3) animals with induced periodontitis and without drug treatment (L); and 4) animals without induced periodontitis and without drug treatment - control (C). After 14 days of treatment, the rats were euthanized. Right hemi-mandibles were removed and lingual alveolar bone loss measurements were made under a stereomicroscope. Left hemi-mandibles were decalcified and submitted to routine histological preparation for the evaluation of alveolar bone loss in furcation regions, amount of gingival collagen, and immunohistochemistry for receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) ratio. Animals treated with isoproterenol had significantly more lingual alveolar bone loss than others. The percentage of collagen in gingiva was greater in the propranolol group than in the isoproterenol group. No statistical differences were found among groups with periodontal disease in any other evaluations. The activation of ß-adrenergic receptors increased the lingual alveolar bone loss; however, in the model used, the use of ß-adrenergic antagonist drugs was not able to modulate the host response significantly. Activation and inhibition of ß-receptors have antagonistic actions in collagen degradation in animals with periodontal disease.

Agreement, correlation, and kinetics of the alveolar bone-loss measurement methodologies in a ligature-induced periodontitis animal model.

Periodontal research involves the use of animal models to better understand the biological processes of periodontal diseases and the potential of new or existing therapies. Currently, ligature-induced periodontitis in rats is the main model used in periodontal research, in this model, alveolar bone loss (ABL) is the main parameter evaluated by radiographic, morphometric, and histological techniques. Interestingly, although these methodologies are widely used, it is not totally clarified neither the kinetics of ABL over the induction time nor the agreement degree (repeatability and reproducibility) of these techniques. OBJECTIVE: To characterize ABL kinetics at 0, 3, 7, 15, 30, and 60 days after ABL induction by ligature and to evaluate the intra- (repeatability) and inter-examiner (reproducibility) agreement and the correlation among the radiographic, morphometric, and histological methodologies. MATERIAL AND METHODS: 60 male Wistar rats with induced ABL were randomly divided into 6 experimental groups (n = 10 animals/group). After 0, 3, 7, 15, 30, and 60 days, the animals were euthanized and their hemimandibles were removed for ABL determination using radiographic, morphometric and histological techniques. RESULTS: Radiographic and morphometric/linear techniques allowed the detection of statistically significant ABL on the third day, while histological and morphometric/area techniques could only detect ABL after the seventh day (ANOVA/Tukey, p<0.05). After the fifteenth day, except for histological analysis, the ABL was stabilized. Concerning the agreement of the methodologies, Bland Altman's test (intra and inter-examiner evaluations) showed no difference among the measurements (p>0.05). In addition, high correlations (Pearson's test, r2>0.9, p<0.05) were observed. CONCLUSION: The results indicated that the minimum time for ABL induction could vary from 3 to 7 days, according to the chosen analysis methodology. Agreement and correlation data support the comparison of results between studies with same induction time.

Absence of medication-related jaw osteonecrosis after treatment with strontium ranelate in ovariectomized rats

Abstract This study aimed to evaluate the potential of strontium ranelate (SR) in medication-related jaw osteonecrosis (MRONJ) after tooth extraction in ovariectomized rats. Thirty ovariectomized rats were divided into three groups (n = 10): bisphophonate (BP) group (zoledronic acid; 0.4 mg/kg/week), SR group (625 mg/kg/day), and control group (saline solution). The lower first molars were extracted after 60 days of drug therapy. Drug administration was continued for another 30 days after tooth extraction. The mandibles were subjected to clinical, histological, radiographic, and microtomographic evaluations. Only the BP group showed clinical changes, characterized by the presence of 70% (n = 7) and 20% (n = 2) of ulcers and extraoral fistulas. Radiographic evaluation demonstrated bone sequestration only in the BP group (n = 7, 70%). Microtomographic analysis revealed increased bone porosity after ovariectomy, particularly in the the control group (p < 0.05). The BP group showed a higher bone surface density, bone volume, and trabecular number than SR and control groups, but with less trabecular separation (p < 0.05). All the animals in the BP group demonstrated histological osteonecrosis. There was no evidence of osteonecrosis in the control and SR groups, which was characterized by the absence of empty osteocyte gaps and associated with the gradual healing of the extraction area. Also, an increased number of blood vessels and a reduced number of osteoclasts were observed in the SR group (p < 0.05). Therefore, SR treatment increased angiogenesis and osteoclastogenesis in the healing socket and was not associated with MRONJ development after tooth extraction in ovariectomized rats.