Cemental and alveolar bone defects after chronic exposure to amoxicillin in rats (histopathologic and radiographic study)

OBJECTIVES

This study aimed to shed new light on the potential detrimental effects on cementum and adjacent alveolar bone after chronic exposure to amoxicillin.

METHODS

Six pregnant adult Albino rats were equally divided into two groups. Saline solution and amoxicillin (100 mg/Kg) were given to rats of control and amoxicillin group, respectively from the 13th to the 21st day of pregnancy. The same treatment was given to the pups till the 42nd day. The cementum of the first molar teeth and the surrounding alveolar bone were examined qualitatively by histopathological and scanning electron microscope, and quantitatively by energy dispersive X-ray spectroscopy and cone beam computed tomography.

RESULTS

Amoxicillin group depicted cemental and alveolar bone defects along with resorption lacunae. Statistically significant decreases in calcium and calcium/phosphorus ratio in cementum and in calcium only in alveolar bone were evident (p ≤ 0.05). Overall cementum and alveolar bone densities also showed statistically significant decreases (p ≤ 0.05).

CONCLUSION

Chronic amoxicillin administration displayed destructive effects on cementum and the surrounding alveolar bone which may disturb tooth attachment integrity. Therefore, it is recommended to minimize its haphazard usage during pregnancy and early childhood.

Prolyl-hydroxylase inhibitor-induced regeneration of alveolar bone and soft tissue in a mouse model of periodontitis through metabolic reprogramming

Bone injuries and fractures reliably heal through a process of regeneration with restoration to original structure and function when the gap between adjacent sides of a fracture site is small. However, when there is significant volumetric loss of bone, bone regeneration usually does not occur. In the present studies, we explore a particular case of volumetric bone loss in a mouse model of human periodontal disease (PD) in which alveolar bone surrounding teeth is permanently lost and not replaced. This model employs the placement a ligature around the upper second molar for 10 days leading to inflammation and bone breakdown and faithfully replicates the bacterially-induced inflammatory etiology of human PD to induce bone degeneration. After ligature removal, mice are treated with a timed-release formulation of a small molecule inhibitor of prolylhydroxylases (PHDi; 1,4-DPCA) previously shown to induce epimorphic regeneration of soft tissue in non-regenerating mice. This PHDi induces high expression of HIF-1α and is able to shift the metabolic state from OXPHOS to aerobic glycolysis, an energetic state used by stem cells and embryonic tissue. This regenerative response was completely blocked by siHIF1a. In these studies, we show that timed-release 1,4-DPCA rapidly and completely restores PD-affected bone and soft tissue with normal anatomic fidelity and with increased stem cell markers due to site-specific stem cell migration and/or de-differentiation of local tissue, periodontal ligament (PDL) cell proliferation, and increased vascularization. In-vitro studies using gingival tissue show that 1,4-DPCA indeed induces de-differentiation and the expression of stem cell markers but does not exclude the role of migrating stem cells. Evidence of metabolic reprogramming is seen by the expression of not only HIF-1a, its gene targets, and resultant de-differentiation markers, but also the metabolic genes Glut-1, Gapdh, Pdk1, Pgk1 and Ldh-a in jaw periodontal tissue.

Effect of red wine and its major components on periodontitis and systemic inflammation in rats

OBJECTIVES

To evaluate the influence of red wine exposure, alcohol, grape juice and resveratrol in the occurrence of spontaneous and ligature induced periodontitis as well as CRP, TNFα and IL-6 levels in Wistar rats.

METHODOLOGY

50 male Wistar rats were randomly assigned to 5 groups (Control, Red Wine, Grape Juice, 12% Alcohol and 0.05mg/mL Resveratrol). All groups were fed with laboratory rat chow and liquid intake according to group allocation. After 8 weeks, ligatures were placed around the maxillary right second molars. The contra-lateral molars remained as intra-group controls. After 14 days, animals were killed, blood samples collected and specimens prepared for analysis. Group comparisons were performed by ANOVA. A cut-off point in the 75th percentile in the side without ligature was used for definition of spontaneous periodontitis.

RESULTS

All animals completed the experiment. According to mean alveolar bone loss, no statistically significant differences were found. Animals exposed to red wine presented a lower occurrence of spontaneous periodontitis, lower levels of TNF-α (0.97 ng/mL) and CRP (0.29 mmol/μL) compared to controls (1.97 ng/mL, p = 0.008 and 0.45 mmol/ μL, p less than or equal to 0.05 respectively).

CONCLUSION

Red wine exposure potentially affects the occurrence of spontaneous periodontitis, CRP and TNF-α levels in Wistar rats.

Periosteal Releasing Incision With Diode Laser in Guided Bone Regeneration Procedure: A Case Series

Introduction: Periosteal releasing incision (PRI) is nearly always essential to advance the flap sufficiently for a tension-free flap closure in bone augmentation procedures. However, hematoma, swelling, and pain are recognized as the main consequences of PRI with scalpel. The aim of this case series was to investigate the effectiveness of laser-assisted PRI in guided bone regeneration (GBR) procedure. In addition, postoperative hematoma, swelling, and pain and implant success were assessed. Methods: Seventeen patients needed GBR were included in this study. Diode laser (940 nm, 2 W, pulse interval: 1 ms, pulse length: 1 ms, contact mode, 400-μm fiber tip) was used in a contact mode to cut the periosteum to create a tension-free flap. Facial hematoma, swelling, pain, and the number of consumed nonsteroidal anti-inflammatory drugs (NSAIDs) were measured for the six postoperative days. Six months after implant loading, implant success was evaluated. Results: Minimal bleeding was encountered during the procedure. A tension-free primary closure of the flap was achieved in all cases. The clinical healing of the surgical area was uneventful. None of the patients experienced hematoma, ecchymosis, or intense swelling after surgery. The mean value of maximum pain (visual analogue scale - VAS) was 20.59 ± 12.10 mm (mild pain). Patients did not need to use NSAID after four postoperative days. All implants were successful and functional and none of them failed after 6 months of implant loading. Conclusion: This study revealed the effectiveness of laser-assisted PRI in GBR procedure. This technique was accompanied with minimal sequelae at the first postoperative week. All implants were successful and no complication was noted during the course of this study.

Periodontal Bone Regeneration and the Er,Cr:YSGG Laser: A Case Report

Background:

Traditional methods of regenerating bone in periodontal bone defects have been partially successful and have involved numerous protocols and materials. More recently, it has been proposed that Er,Cr:YSGG laser energy may also be beneficial in the treatment of periodontal pockets, particularly in the regeneration of bone lost due to periodontal disease.

Case Description:

The purpose of this paper is to present a case report of the Er,Cr:YSGG laser being used to conservatively treat a recalcitrant periodontal pocket in the presence of a periodontal bone defect and that resulted in successful resolution of the pocket and significant radiographic bone fill at the 1 year recall visit.

Clinical Implications:

This protocol using the Er,Cr:YSGG laser for the treatment of periodontal loss of attachment and periodontal bone loss may represent a less invasive alternative than traditional open-flap periodontal surgery or the intrasulcular use of other more penetrating laser wavelengths.