Blood loss following dental extractions in anticoagulated rabbits: effects of tranexamic acid and socket packing

Keratinocytes: An Enigmatic Factor in Atopic Dermatitis

Atopic dermatitis (AD), characterized by rashes, itching, and pruritus, is a chronic inflammatory condition of the skin with a marked infiltration of inflammatory cells into the lesion. It usually commences in early childhood and coexists with other atopic diseases such as allergic rhinitis, bronchial asthma, allergic conjunctivitis, etc. With a prevalence rate of 1–20% in adults and children worldwide, AD is gradually becoming a major health concern. Immunological aspects have been frequently focused on in the pathogenesis of AD, including the role of the epidermal barrier and the consequent abnormal cytokine expressions. Disrupted epidermal barriers, as well as allergic triggers (food allergy), contact allergens, irritants, microbes, aggravating factors, and ultraviolet light directly initiate the inflammatory response by inducing epidermal keratinocytes, resulting in the abnormal release of various pro-inflammatory mediators, inflammatory cytokines, and chemokines from keratinocytes. In addition, abnormal proteinases, gene mutations, or single nucleotide polymorphisms (SNP) affecting the function of the epidermal barrier can also contribute towards disease pathophysiology. Apart from this, imbalances in cholinergic or adrenergic responses in the epidermis or the role played by immune cells in the epidermis such as Langerhans cells or antigen-presenting cells can also aggravate pathophysiology. The dearth of specific biomarkers for proper diagnosis and the lack of a permanent cure for AD necessitate investigation in this area. In this context, the widespread role played by keratinocytes in the pathogenesis of AD will be reviewed in this article to facilitate the opening up of new avenues of treatment for AD.

Comparison of uninterrupted warfarin and bridging therapy using low-molecular weight heparin with respect to the severity of bleeding after dental extractions in patients with prosthetic valves

Objective:

The management of anticoagulated patients with warfarin during dental extraction is an intricate issue. We carefully designed the current study so that the amount of bleeding was measured with objective methods and the data from the same patient in different dental extraction appointments could be compared, eliminating the bleeding diathesis differences of patients.

Methods:

This prospective and controlled study was conducted in 36 adult patients with prosthetic valve requiring multiple tooth extractions. The first dental extraction was performed without the discontinuation of warfarin therapy, and the second procedure was performed with a discontinuation of warfarin and bridging with low-molecular weight heparin (LMWH). The two dental extraction protocols in the same patient group were compared. The total amount of bleeding was calculated as the difference between the weights of gauze swabs used before and after the tamponade; the number of gauze swabs used for bleeding control in the first 48 h was recorded.

Result:

The median number of used gauze swabs was 2.5 (IQR: 1–5) and 3.0 (IQR: 2–7) in the first and second dental extraction procedures, respectively. The median bleeding time was 50.0 (IQR: 20–100) in the first procedure compared with 60.0 (IQR: 40–140) min in the second procedure. The mean amounts of bleeding were 2194±1418 mg in the first dental extraction procedure and 2950±1694 mg in the second dental extraction procedure. The median number of used gauze swabs, the median bleeding time, and the mean amount of bleeding were statistically higher in the second dental extraction procedure (p<0.001).

Conclusion:

Continued warfarin treatment at the time of dental extractions reduces the total amount of bleeding compared with bridging therapy in patients with prosthetic valves.

Comparison of the effects of warfarin and heparin on bleeding caused by dental extraction: a clinical study

PURPOSE

Replacement of warfarin with heparin for dental extractions in patients on long-term warfarin therapy is associated with wasted time, consumed labor, and increased treatment expenses. The aim of this study was to evaluate the safety of dental extraction without altering the warfarin regimen in patients with an international normalized ratio from 1 to 4.

PATIENTS AND METHODS

Forty patients who underwent tooth extraction were divided into 4 groups: continuation of warfarin without interruption (group 1), warfarin bridged with low-molecular-weight heparin (group 2), warfarin bridged with unfractionated heparin (group 3), and a control group of healthy individuals (group 4). Total amount of bleeding (milligrams) was measured for 20 minutes after tooth extraction. International normalized ratio values on the operative day and number of extra gauze swabs used for bleeding control in the first 48 hours were recorded for each patient. Results were statistically analyzed by analysis of variance, Fisher least-significant difference post hoc test, Pearson correlation, χ(2) test, and Student t test.

RESULTS

Mean amounts of bleeding were 2,486 ± 1,408; 999 ± 425; 1,288 ± 982; and 1,736 ± 876 mg for groups 1, 2, 3, and 4, respectively. There was no severe postoperative bleeding in any patient and the number of used extra gauze swabs did not differ significantly among groups.

CONCLUSION

With the aid of local hemostatic agents, dental extraction in patients receiving warfarin who have an international normalized ratio from 1 to 4 could be carried out without a significant risk of bleeding and without altering the anticoagulant regimen.

In-vitro-Testung der Thrombozytenaggregation an zahnärztlich verwendeten kollagenen Hämostyptika

AIM

The aim of the present study was to evaluate the adhesion of thrombocytes to different collagenous hemostyptics in a new blood flow chamber.

MATERIAL AND METHODS

Three hemostyptics were tested: (1) Resorba (RE, native equine collagen, Resorba Wundversorgung GmbH, Nürnberg, Germany), (2) Hemocol (HE, native porcine collagen, Medical Biomaterial Products GmbH, Neustadt-Gleve, Germany), and (3) an experimental sponge (ES, chemically cross-linked porcine collagen, Geistlich Biomaterials, Wolhusen, Switzerland). Ten specimens of each sponge were exposed to a laminar 40 ml/h anticoagulated blood flow and adhering thrombocytes were examined using a confocal laser scanning microscope (CLSM). Pure collagen (Kollagen S, Roche) served as positive control and fetal calf serum (FKS, Roche) as negative control. Examination time was set at 0, 60, 120, and 180 s. Furthermore, pH measurements of defined sponge volumes were evaluated after incubation with NaCl and human blood serum after 3, 30, and 60 min.

RESULTS

All specimens showed a comparable amount of fluorescence units on the surface over time which was statistically not significantly different from the positive control (p>0.05, ANOVA). Nevertheless, acidity of all specimens could be observed after incubation with NaCl and in cases of HE and ES after incubation with human blood serum.

CONCLUSION

Within the limits of the present in-vitro study it was concluded that (1) all hemostyptics examined showed similar results in thrombocyte adhesion; (2) chemical cross-linking of collagen does not affect the thrombogenicity of the tested collagen; (3) however, the acidity might have a negative effect on thrombus formation in vivo.

Comparison of laboratory and immediate diagnosis of coagulation for patients under oral anticoagulation therapy before dental surgery

Background

Dental surgery can be carried out on patients under oral anticoagulation therapy by using haemostyptic measures. The aim of the study was a comparative analysis of coagulation by laboratory methods and immediate patient diagnosis on the day of the planned procedure.

Methods

On the planned day of treatment, diagnoses were carried out on 298 patients for Prothrombin Time (PT), the International Normalised Ratio (INR), and Partial Thromboplastin Time (PTT). The decision to proceed with treatment was made with an INR < 4.0 according to laboratory results.

Results

Planned treatment did not go ahead in 2.7% of cases. Postoperatively, 14.8% resulted in secondary bleeding, but were able to be treated as out-patients. 1.7% had to be treated as in-patients. The average error between the immediate diagnosis and the laboratory method: 95% confidence interval was -5.8 ± 15.2% for PT, -2.7 ± 17.9 s for PTT and 0.23 ± 0.80 for INR. The limits for concordance were 9.4 and -21.1% for PT, 15.2 and -20.5 s for PTT, and 1.03 and -0.57 for INR.

Conclusion

This study showed a clinically acceptable concordance between laboratory and immediate diagnosis for INR. Concordance for PT and PTT did not meet clinical requirements. For patients under oral anticoagulation therapy, patient INR diagnosis enabled optimisation of the treatment procedure when planning dental surgery.

Fibrin adhesive implant in wound healing repair of dental sockets with topical application of epsilon aminocaproic acid: Histological analysis

The aim of the study was to evaluate wound healing repair of dental sockets after topical application of 5% epsilon-aminocaproic acid (EACA) and the use of fibrin adhesive implant in rats under anticoagulant therapy with warfarin. Sixty Albinus wistar rats were used, divided into three groups of 20. In Group I, the animals were given 0.1 mL/100 mg of 0.9% saline solution per day, beginning 6 days before dental extraction and continuing throughout the experimental period. In Group II, the animals received 0.03 mL of sodium warfarin daily, beginning 6 days before the surgery and continuing until the day of sacrifice; after tooth extractions, the sockets were filled with fibrin adhesive material. In Group III the animals were treated as in Group II, and after extractions, the sockets were irrigated with 5 mL of 5% EACA and filled with the same fibrin adhesive material. All groups presented biological phases of wound healing repair, the differences being evident only in the chronology. The results obtained in Group III were very similar to those of Group I in the last period of wound repair, whereas Group II presented a late chronology compared to the other groups.

Can warfarin be continued during dental extraction? Results of a randomized controlled trial

A randomized controlled trial was set up to investigate whether patients who were taking warfarin and had an International Normalised Ratio (INR) within the normal therapeutic range require cessation of their anticoagulation drugs before dental extractions. Of 109 patients who completed the trial, 52 were allocated to the control group (warfarin stopped 2 days before extraction) and 57 patients were allocated to the intervention group (warfarin continued). The incidence of bleeding complications in the intervention group was higher (15/57, 26%) than in the control group (7/52, 14%) but this difference was not significant. Two patients in the study required hospital review for bleeding and all other episodes of bleeding were controlled by patients at home. Continuing warfarin when the INR is < 4.1 may lead to an increase in minor post-extraction bleeding after dental extractions but we found no evidence of an increase in clinically important bleeding. As there are risks associated with stopping warfarin, the practice of routinely discontinuing it before dental extractions should be reconsidered.

Dental extractions in patients on warfarin: is alteration of anticoagulant regime necessary?

Various clinical protocols for the management of warfarinised patients needing dental extractions have been suggested. This study was designed to compare two approaches in the management of these patients. A control group of 32 patients had their warfarin treatment stopped for 2-3 days prior to having dental extractions, resulting in a reduction in the average preoperative international normalised ratio (INR) from 2.6 to 1.6. The study group of 33 patients did not have their anticoagulant treatment altered before extractions, and had an average preoperative INR of 2.7. All patients were treated under local analgesia on an outpatient basis, and local measures-consisting of Surgicel pack and sutures-were used in all cases to control postoperative bleeding from extraction sockets. None of the patients had any immediate postoperative bleeding, and only 1 patient from each group had mild delayed haemorrhage, which was easily controlled with local measures. It is proposed that, provided the INR is within the therapeutic range of 2.0 to 4.0 and local measures are used to control postoperative bleeding, there is no justification in altering warfarin treatment prior to dental extractions in these patients, and thereby exposing them to the risk of thromboembolism.

Clinical and magnetic resonance imaging findings in temporomandibular joint disc displacement

OBJECTIVES

To describe the clinical and MRI findings in patients with disc displacement of the temporomandibular joint.

METHODS

Eighty-eight joints in 51 patients referred for suspected TMJ disc displacement were examined by MRI. Two oral radiologists assessed the images. The clinical findings were obtained by retrospective review of the patients' records.

RESULTS

Clicking was the most common clinical finding, present in 47 joints. Pain was reported for only 30 joints. Anterior disc displacement with reduction was found in 39 joints, anterior disc displacement without reduction in 31 joints, compound dislocations (anterolateral or anteromedial) in 13 joints and sideways displacement in 5 joints respectively. In about one-fourth of the joints, MRI revealed abnormal configuration of both disc and condyle. The osseous changes were subtle. Only 9% of the joints exhibited an osteophyte. Joint effusion in either the upper or the lower joint compartment was found in 19 joints. Out of 14 patients with joint effusion, six patients complained of pain from the TMJ region.

CONCLUSION

The most extensive soft and hard tissue changes were found in patients with anterior disc displacement without reduction. Pain was not a characteristic symptom for any type of disc displacement.

Current perspectives on dental patients receiving coumarin anticoagulant therapy

Despite approximately 40 years of experience with oral anticoagulant drugs, controversy still exists about the safety of dental treatment in a patient receiving this therapy. The authors review the topic in depth and offer detailed recommendations for the dental management of patients receiving coumarin anticoagulant therapy.

Pretreatment management of the patient receiving anticoagulant drugs

This literature review suggests that certain low-risk dental treatment procedures can be performed in patients without altering their anticoagulant medications. Intermediate-risk dental procedures in these patients may be accomplished outside the hospital if the patient's prothrombin time value is within a specified range and if certain techniques are followed. In some cases, temporarily altering the dose of anticoagulant may be necessary. Patients receiving anticoagulant medications should continue to receive high-risk dental treatment in hospitals.

Fibrinolytic alveolitis and its prevention

This study aimed at testing the clinical efficacy of a topical prevention of FA, the sample comprising 300 cases of extractions. A sponge was inserted in the socket of each of them, dividing the sample into 3 equal groups: group A (gelatine), group B (gelatine + Solcoseryl) and group C (gelatine + Solcoseryl + propyl-hydroxy-benzoic-acid). The global incidence of FA was a comparatively high, 7.6%, which could be related to the pool of patients included in the study as to the presence of teeth and techniques more prone to complications. No specific clinical characteristic has been isolated (distribution within sex, age, teeth, etc.) which could contradict data collected from other authors. The incidence was lower in the groups B (3%) and C (7%) as compared to group A (13%), but only sponges of group B demonstrated a clinical and statistical efficacy, according to the high number of lower third molar extractions. In contrast, the addition of Solcoseryl proves efficient and does not delay healing, according to previous histological studies. This last characteristic has to be confirmed in the experimental conditions described in our study, as has its mode of action. The ultimate mechanism of FA has still, in our opinion, to be better defined well before the restatement of a topical prevention of FA.

Dental treatment for the patient on anticoagulant therapy: prothrombin time value--what difference does it make?

Thirty patients taking anticoagulants received routine dental treatment without altering their prothrombin time values. In a follow-up of 5 years, no serious complications were seen in patients with a prothrombin time value of up to 2.5. A protocol is suggested for dental treatment in these patients.