Influence of titanium implant macrodesign on peri-implantitis occurrence: a cross-sectional study.

OBJECTIVES: To assess whether implant macrodesign parameters interacting with implant time in function (Tf) could influence the peri-implantitis occurrence. MATERIALS AND METHODS: One hundred and two patients (55.17 ± 11.2 years old) with diagnosed early/moderate peri-implantitis around endosseous implants with implant-supported prosthetics reconstruction (n = 139) were recruited. Implant macrodesign (implant shape, thread number, implant collar), clinical parameters (peri-implant probing depth (PPD), clinical attachment level (CAL), keratinised tissue width (KTW), plaque index, bleeding on probe), implant placement localisation and region, and Tf were assessed and compared. RESULTS: Peri-implantitis occurred approximately 6.1 ± 3.38 years after implant loading. There was a significant positive correlation between the implant macrodesign and Tf. Peri-implantitis rates were statistically significantly higher in implants with a cylindric shape and triple-thread in the posterior part of the mandible (p = 0.037 and 0.012, respectively). The thread number and implant shape interacting with Tf showed statistically significant influences on CAL and PPD increase (p < 0.05). Results indicated a statistically positive interaction between Tf and KTW decrease around the implants with microthreaded collar (p < 0.001). CONCLUSION: Peri-implantitis might be presented as a time-dependent disease. Implant-based factors, such as Tf and implant macrodesign, could influence peri-implantitis occurrence, exacerbate clinical parameters, and promote progressive bone loss. CLINICAL RELEVANCE: Peri-implantitis can be affected by implant macrodesign and Tf. The implant body shape, thread number, and design of the implant collar may be considered peri-implantitis-related risk indicators that should be taken into account in proper implant planning and therapy.

Primary Stability of Trabecular Metal Implant in Comparison to Fully Threaded Implants: In Vitro Study Simulating Immediate Implant Placement.

The aim of this study was to evaluate primary stability of 3.7-mm diameter porous tantalum Trabecular Metal (TM) implant, and compare it to fully threaded implants, in the in vitro model of immediate implant placement in the anterior maxilla. A total of 60 implants were placed into bovine ribs using surgical guides. Implants were divided in 3 groups of 20 according to the design: TM, Tapered Screw-Vent (TSV), and NobelReplace. To simulate immediate placement in anterior maxilla, implants were placed under a sharp angle toward the ribs, not fully submerged. Placement angle of 20.7° was calculated after analysis of 148 virtually planned implants on cone beam computerized tomography scans of 40 patients. No statistically significant difference in implant stability quotient (ISQ) was found between TM (65.8 ± 2.6), TSV (64.7 ± 2.7), and NobelReplace (64.6 ± 2.7). TSV implants achieved higher insertion torque (37.0 ± 4.8 Ncm) than TM (32.9 ± 5.2 Ncm) and NobelReplace (23.2 ± 3.3 Ncm). TSV had the shortest insertion time of 13.5 ± 1.0 seconds, compared to 15.2 ± 1.2 seconds for TM, and 19.7 ± 1.7 seconds for NobelReplace. Pearson correlation analysis showed significantly correlated insertion torque and ISQ values for TM group (P = .011, r = .56), a nonsignificant correlation was found for TSV and NobelReplace. The results of the present study indicate that TM implant can achieve good primary implant stability in insertion torque and resonance frequency analysis.

Clinical Characteristics of Abutment Teeth with Gingival Discoloration.

PURPOSE: The grey-bluish discoloration of gingiva (known as "amalgam tattoo") does not appear only in the presence of amalgam restorations. It may also be seen in cases of teeth restored with cast dowels and porcelain-fused-to-metal (PFM) restorations. The aim of this article was to determine the clinical characteristics of abutment teeth with gingival discoloration. MATERIALS AND METHODS: This research was conducted on 25 patients referred for cast dowel and PFM restorations. These restorations were manufactured from Ni-Cr alloys. Ninety days after cementing the fixed prosthodontic restorations, the abutment teeth (n = 61) were divided into a group with gingival discoloration (GD) (n = 25) and without gingival discoloration (NGD) (n = 36). The control group (CG) comprised the contralateral teeth (n = 61). Plaque index, gingival index, clinical attachment level, and probing depth were assessed before fabrication and also 90 days after cementation of the PFM restorations. RESULTS: The gingival index, clinical attachment level, and probing depths of the abutment teeth that had GD were statistically higher before restoration, in comparison with the abutment teeth in the NGD and control groups. Ninety days after cementation, the abutment teeth with GD had significantly lower gingival indexes and probing depths, compared to the abutment teeth in the NGD group. Both abutment teeth groups (GD and NGD) had significantly higher values of clinical attachment levels when compared to the control group. There were no statistically significant differences in plaque index values between the study groups. CONCLUSIONS: The results of this study indicated that impairment of periodontal status of abutment teeth seemed to be related to the presence of gingival discolorations. Therefore, fabrication of fixed prosthodontic restorations requires careful planning and abutment teeth preparation to minimize the occurrence of gingival discolorations. CLINICAL RELEVANCE: With careful preparation of abutment teeth for cast dowels and crown restorations it may be possible to decrease the frequency of gingival discolorations adjacent to abutment teeth.

Histopathological comparative analysis of periimplant bone inflammatory response after dental implant insertion using flap and flapless surgical technique. An experimental study in pigs.

AIM: To evaluate by histopathological analysis the peri-implant bone inflammation degree, in certain time intervals (7, 14, 21 and 28 days), following mini-incision flapless and flap implant placement. MATERIAL AND METHODS: The experiment was conducted on four domestic pigs. Nine weeks prior to implant insertion, second and third mandibular premolars were extracted. Each animal received six implants in lower jaw. On one randomly chosen side of jaw flapless technique using mini-incision was performed, while on the other side implants were inserted after flap raising. After 7, 14, 21, and 28 days, the experimental animals were sacrificed. Following mandibular resection and decalcification, the samples for histopathological analysis of the peri-implant bone were obtained in the empty implant bed area, from the buccal side of the mandible, adjacent to implant neck region and parallel to crestal edge of implant bed. The degree of inflammatory response of the peri-implant bone was estimated through ordinal scores from 0 to 2. RESULTS: Seven days after the surgery all samples in the flap group had score 2 indicating high inflammation degree, in contrast to lower inflammatory reaction in flapless group. On the 14th and 21st postoperative day decreasing of inflammation degree was noted in all samples of the flapless group (score 1), while in flap group samples presented scores 1 and 2. Twenty-eight days after the implant placement, further reduction of inflammation in the flapless group (33% of samples had score 0) was observed. CONCLUSION: Flapless technique in comparison to conventional flap procedure minimizes postoperative bone inflammatory reactions.

Immunohistochemical analysis of blood vessels in peri-implant mucosa: a comparison between mini-incision flapless and flap surgeries in domestic pigs.

AIM: The aim of this experimental study is to compare the effect of mini-incision flapless versus flap technique of implant placement on the amount of vascular structures and blood vessel elements in peri-implant soft tissue, using immunohistochemical analysis. METHOD: The experiment was conducted on five domestic pigs. Each animal received six implants in mandible according to the split-mouth design. On one randomly chosen jaw side, mini-incision flapless surgery was performed, whereas on the opposite jaw side, flap was raised. After 3 months of implant healing through submerged approach, the experimental animals were sacrificed and samples for immunohistochemical analyses were taken from the buccal side of peri-implant mucosa next to the neck of implants, from three levels. The study outcome was the presence of vascular structures and elements of the blood vessels in the peri-implant mucosa per microscopic field, estimated through ordinal scores from 0 to 2. Effects of surgical approach, site of implantation, and their interaction on vascular scores of peri-implant mucosa were assessed by Brunner and Langer nonparametric analysis of longitudinal data. RESULTS: Statistically significant effect of surgical approach on vascularity of peri-implant mucosa has been revealed in the second mucosal layer, where flapless approach provided higher vascularity compared with flap approach (P = 0.002). In the remaining two layers, surgical approach did not affect mucosal vascularity significantly (layer 1: P = 0.071; layer 3: P = 0.433). CONCLUSION: The flapless surgical implant placement approach using mini-incision provides better vascularization of peri-implant mucosa after 3 months of healing compared with flap surgery.

Prevalence and prediction of previously unrecognized peripheral arterial disease in patients with coronary artery disease: the Peripheral Arterial Disease in Interventional Patients Study.

BACKGROUND: Peripheral arterial disease (PAD) is under diagnosed in primary care practices, yet the extent of unrecognized PAD in patients with coronary artery disease (CAD) is unknown. OBJECTIVE: To assess the prevalence of previously unrecognized PAD in patients undergoing coronary angiography and/or intervention and to determine the relationship between presence of PAD and severity of CAD. METHODS: The Peripheral Arterial Disease in Interventional Patients Study (PIPS) is a prospective cohort study conducted at an inpatient service of a tertiary referral center. A total of 800 patients referred for coronary angiography without prior diagnosis of PAD aged 70 years or older or aged 50-69 years with a history of tobacco use and/or diabetes mellitus were included. Evaluation involved a medical history, a questionnaire to assess symptoms and functional status, and measurement of the ankle-brachial index (ABI). PAD was considered present if the ABI was 0.90 or less. RESULTS: The prevalence of previously unrecognized PAD was 15%, 95% CI (12.6-17.7) and was highest among patients over 70 years of age (25.2%) and in women (23.3%). Among patients with CAD, those with PAD had higher prevalence of left main and multivessel coronary artery disease (87.2% vs. 75.5%, P = 0.006). Alternatively, patients with multivessel CAD had a twofold higher risk of being diagnosed with previously unrecognized PAD compared with those with single vessel CAD [adjusted OR = 2.02, (95% CI 1.03-3.98)]. CONCLUSIONS: PAD is often overlooked even in patients with known ischemic heart disease under specialist cardiovascular care. Overlooked PAD in this population increases in frequency with advanced age, in women, and in the presence of other traditional cardiovascular risk factors. Furthermore, the presence of PAD in this population identifies a subgroup with more severe form of CAD.

Efficiency of photodynamic therapy in the treatment of peri-implantitis ­ A three-month randomized controlled clinical trial.

Introduction: Peri-implantitis is an inflammatory lesion of peri-implant tissues. Eradication of the causative bacteria and decontamination of the implant surface is essential in achieving predictable and stabile clinical results. Photodynamic therapy (PDT) is non-invasive adjuvant therapeutic method to surgery in the treatment of bacterial infection. Objective: The aim of this study was to evaluate early clinical and microbiological outcomes of periimplantitis after surgical therapy with adjuvant PDT. Methods: Fifty-two diagnosed peri-implantitis sites were divided into two groups. PDT was used for decontamination of implant surface in the study group; in the control group, chlorhexidine gel (CHX) followed by saline irrigation was applied. Several clinical parameters were recorded before the treatment (baseline values) and three months after surgical treatment. Samples for microbiological identification were collected before therapy, during the surgical therapy (before and after decontamination of implant surface), and three months thereafter, and analyzed with identification systems using biochemical analysis. Results: The use of PDT resulted in significant decrease of bleeding on probing in comparison to CHX (p < 0.001). It showed significant decontamination of implant surfaces with complete elimination of anaerobic bacteria immediately after surgical procedure and three months later. Conclusion: The results indicate that PDT can be used as an adjuvant therapy to surgery for decontamination of implant surface and surrounding peri-implant tissues within the treatment of peri-implantitis.

The use of hyaluronic and aminocaproic acid in the treatment of alveolar osteitis.

Background/Aim: Alveolar osteitis (AO), also known as "dry socket", is relatively common post-extraction complication. It probably occurs due to excessive fibrinolytic activity in the coagulum and is characterized by intense pain sensations. The aim of this clinical study was to examine the role of hyaluronic acid and aminocaproic acid in the treatment of AO. Methods: The study included 60 patients with the clinical diagnosis of AO. All the patients were divided into two groups of 30 patients each according to the applied non-pharmacological measure: irrigation ­ irrigation of dry socket with sterile saline; curettage ­ careful curettage. Both of these groups were further divided into three subgroups regarding the applied treatment (hyaluronic acid; hyaluronic acid + aminocaproic acid; Alvogyl ®, an anesthetic and antiseptic paste), each with 10 patients, according to the following protocol: 0.2 mL of hyaluronic acid in the form of a 0.8% gel; 2 mL of aminocaproic acid and hyaluronic acid; Alvogyl®. During each visit, scheduled for every two days until complete absence of painful sensations, the patients had the therapeutic method repeated as at the first examination. At each control visit the number of present symptoms and signs of AO was recorded, as well as the level of pain (measured with a visual analogue scale). Results: With the use of hyaluronic acid, with or without aminocaproic one, a statistically significantly faster reduction in pain sensations was achieved, along with the reduction in the number of symptoms and signs of AO compared to the use of Alvogyl®. Conclusion: Hyaluronic acid, applied alone or in combination with aminocaproic acid significantly reduces pain sensation, thus it can be successfully used in the treatment of AO.

Effect of surgical drill guide and irrigans temperature on thermal bone changes during drilling implant sites - thermographic analysis on bovine ribs.

Background/Aim: During drilling implant sites, mechanical energy is converted into thermal one resulting in transient rise in temperature of surrounding bone. The temperature of 47°C exeeding one minute impairs osseointegration, compromises mechanical properties of the local bone and could cause early implant failure. This in vitro study aimed to assess the effect of surgical drill guide and temperature of irrigans on thermal changes of the local bone during drilling implant sites, and to test the influence of irrigans temperature on the temperature of surgical drill guide. Methods: A total of 48 specimens obtained from bovine ribs were randomly allocated to four experimental conditions according to the 2 x 2 factorial design: drill guide (with or without) and saline (at 25°C or 5°C). Real-time infrared thermography was used as a method for temperature measurement. The primary outcome was bone temperature change during drilling implant sites measured at 3 osteotomy depths, whereas the second one was change in the temperature of the drill guide. Data were analyzed by Brunner and Langer nonparametric analysis and Wilcoxon test. Results: The effect of drill guide on the changes of bone temperature was significant at the entrance of osteotomy, whereas the effect of saline temperature was significant at all osteotomy levels (p < 0.001). No significant interaction was found (p > 0.05). Guided surgery and irrigation with saline at 25°C were associated with the highest bone temperature increase. Increase in drill guide temperature was significantly higher when saline at 25°C was used (p < 0.001). Conclusion: Guided implant site preparation generates higher temperature of the local bone than conventional drilling, not exceeding the threshold for thermal bone necrosis. Although saline at room temperature provides sufficient heat control during drilling, cooled saline is more effective regardless the use of surgical drill guide.

Influence of postoperative low-level laser therapy on the osseointegration of self-tapping implants in the posterior maxilla: a 6-week split-mouth clinical study.

BACKGROUND/AIM: Low-level laser therapy (LLLT) has been proven to stimulate bone repair, affecting cellular proliferation, differentiation and adhesion, and has shown a potential to reduce the healing time following implant placement. The aim of this clinical study was to investigate the influence of postoperative LLLT osseointegration and early success of self-tapping implants placed into low-density bone. METHODS: Following the split-mouth design, self-tapping implants n = 44) were inserted in the posterior maxilla of 12 patients. One jaw side randomly received LLLT (test group), while the other side was placebo (control group). For LLLT, a 637 nm gallium-aluminum-arsenide (GaAlAs) laser (Medicolaser 637, Technoline, Belgrade, Serbia) with an output power of 40 mW and continuous wave was used. Low-level laser treatment was performed immediately after the surgery and then repeated every day in the following 7 days. The total irradiation dose per treatment was 6.26 J/cm2 per implant. The study outcomes were: implant stability, alkaline-phosphatase (ALP) activity and early implant success rate. The follow-up took 6 weeks. RESULTS: Irradiated implants achieved a higher stability compared with controls during the entire follow-up and the difference reached significance in the 5th postoperative week (paired t-test, p = 0.030). The difference in ALP activity between the groups was insignificant in any observation point (paired t-test, p > 0.05). The early implant success rate was 100%, regardless of LLLT usage. CONCLUSION: LLLT applied daily during the first postoperative week expressed no significant influence on the osseointegration of self-tapping implants placed into low density bone of the posterior maxilla. Placement of self-tapping macro-designed implants into low density bone could be a predictable therapeutic procedure with a high early success rate regardless of LLLT usage.

Implant stability and marginal bone level of microgrooved zirconia dental implants: A 3-month experimental study on dogs.

BACKGROUND/AIM: The modification of implant surfaces could affect mechanical implant stability as well as dynamics and quality of peri-implant bone healing. The aim of this 3-month experimental study in dogs was to investigate implant stability, marginal bone levels and bone tissue response to zirconia dental implants with two laser-micro-grooved intraosseous surfaces in comparison with nongrooved sandblasted zirconia and sandblasted, high-temperature etched titanium implants. METHODS: Implant surface characterization was performed using optical interferometric profilometty and energy dispersive X-ray spectroscopy. A total of 96 implants (4 mm in diameter and 10 mm in length) were inserted randomly in both sides of the lower jaw of 12 Fox Hound dogs divided into groups of 24 each: the control (titanium), the group A (sandblasted zirconia), the group B (sandolasted zirconia plus microgrooved neck) and the group C (sandblasted zirconia plus all microgrooved). All the implants were immediately loaded. Insertion torque, periotest values, radiographic crestal bone level and removal torque were recorded during the 3-month follow-up. Qualitative scanning electon microscope (SEM) analysis of the bone-implant interfaces of each group was performed. RESULTS: Insertion torque values were higher in the group C and control implants (p < 0.05). Periotest values increased in all the periods in proportion to the extent of microgrooving as follows: the group C > the control > the group B > the group A (p < 0.05). Radiographic measurements showed minimal crestal bone loss at 3 months for microgrooved zirconia implants (groups C and B) and control implants compared with the group A implants (p < 0.05). The removal torque values increased with time for all the groups as follows: the group C > the control > the group B > the group A (p < 0.05). SEM showed that implant surfaces of the groups B and C had an extra bone growth inside the microgrooves that corresponded to the shape and direction of the microgrooves. CONCLUSION: The addition of microgrooves to the entire intraosseous surface of zirconia dental implants enhances primary and secondary implant stability, promotes bone tissue ingrowth and preserves crestal bone levels.

Comparative radiographic and resonance frequency analyses of the peri-implant tissue after dental implants placement using flap and flapless techniques: an experimental study on domestic pigs.

BACKGROUND/AIM: Flapless implant surgery has become very important issue during recent years, mostly thanks to computerization of dentistry and software planning of dental implants placements. The aim of this study was to compare flap and flapless surgical techniques for implant placement through radiographic and radiofrequency analyses. METHODS: The experiment was made in five domestic pigs. Nine weeks following domestic pigs teeth extraction, implants were placed, on the right side using surgical technique flap, and flapless on the left side. Digital dental Xrays were applied to determine primary dental implant stability quality (ISQ). At certain intervals, not later than three months, the experimental animals were sacrificed, and just before it, control X-rays were applied to measure dental implants stability. RESULTS: Radiographic analysis showed that peri-implant bone resorption in the first 4 weeks following placement implants with flap and flapless surgical techniques was negligible. After the 3 months, mean value of peri-implant bone resorption of the implants placed using flap tehnique was 1.86 mm, and of those placed using flapless tehnique was 1.13 mm. In relation to the primary dental implant stability in the first and second week there was an expected decrease in ISQ values, but it was less expressed in the dental implants placed using the flapless technique. In the third week the ISQ values were increased in the dental implants placed by using both techniques, but the increase in flapless implant placement was higher (7.4 ISQ) than in flap implant placement (1.5 ISQ). The upward trend continued in a 4-week period, and after 3 months the dental implant stability values in the implants placed using flap technique were higher than the primary stability for 7.1 ISQ, and in the implants placed using flapless technique were higher comparing to the primary stability for 10.1 ISQ units. CONCLUSION: Based on the results of radiographic and resonance frequency analyses it can be concluded that the flapless technique in surgical implants placemat, leads to better results.

Therapeutic efficacy of connective tissue autotransplants with periosteum and platelet rich plasma in the menagement of gingival recession.

BACKGROUND/AIM: Gingival recession progression in clinical practice has influenced the development of various surgical procedures and techniques for solving esthetic imperfections and subjective difficulties coused by gingival recession. The aim of this study was to verify efficacy of surgical procedures and to compare both of surgical procedures through the keratinized tissue width. METHODS: The study included 20 teeth with gingival recesion, Müller class I and II. Ten teeth with gingival recession were treated with connective tissue autotransplants with periosteum in combination with coronary guided surgical flap (CTG group). On the contralateral side 10 teeth with gingival recession were treated with the same surgical procedures but in combination with platelet-rich plasma (CTG-PRP group). We measured the keratinized tissue width. For statistical significance we used the Student's t-test. RESULTS: The study reveled a statistical significance in reducing vertical deepress of recession by both used treatments. Root deepness in CTG and CTG-PRP group was 90% and 93.5%, respectively. With both surgical techniques we achieved larger zone of keratinized gingiva but with a wide zone of keratinized tissue in CTG--the PRP group. CONCLUSION: The concept regeneration technique with PRP and with the stimulating influence of platele activated growth factors results in the regeneration of deep periodontal tissue as an important prerequisite for the successfull treatment of gingival recession.

Evaluation of primary stability of self-tapping and non-self-tapping dental implants. A 12-week clinical study.

PURPOSE: The aim of this study was to investigate the relationship between surgical techniques and implant macro-design (self-tapping/non-self-tapping) for the optimization of implant stability in the low-density bone present in the posterior maxilla using resonance frequency analysis (RFA). MATERIALS AND METHODS: A total of 102 implants were studied. Fifty-six self-tapping BlueSkyBredent® (Bredent GmbH&Co.Kg®, Senden, Germany) and 56 non-self-tapping Standard Plus Straumann® (Institut Straumann AG®, Waldenburg, Switzerland) were placed in the posterior segment of the maxilla. Implants of both types were placed in sites prepared with either lateral bone-condensing or with bone-drilling techniques. Implant stability measurements were performed using RFA immediately after implant placement and weekly during a 12-week follow-up period. RESULTS: Both types of implants placed after bone condensing achieved significantly higher stability immediately after surgery, as well as during the entire 12-week observation period compared with those placed following bone drilling. After bone condensation, there were no significant differences in primary stability or in implant stability after the first week between both implant types. From 2 to 12 postoperative weeks, significantly higher stability was shown by self-tapping implants. After bone drilling, self-tapping implants achieved significantly higher stability than non-self-tapping implants during the entire follow-up period. CONCLUSIONS: The outcomes of the present study indicate that bone drilling is not an effective technique for improving implant stability and, following this technique, the use of self-tapping implants is highly recommended. Implant stability optimization in the soft bone can be achieved by lateral bone-condensing technique, regardless of implant macro-design.

[Fracture toughness of zirconia ceramic crowns made by feather-edge tooth preparation design].

BACKGROUND/AIM: Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of reduction of their mechanical properties. This research was done to establish effects of feather-edge tooth preparation on fracture toughness of single zirconia ceramic crowns. METHODS: The research was performed as an experimental study. Sixty (60) ceramic crowns were made on non-carious extracted human premolars. Thirty (30) crowns were made on the basis of feather-edge preparation (experimental group I). The group II included 30 crowns made on 1 mm rounded shoulder. Crowns fabrication was executed on a copy mill production system "Zirkonzahn" (Zirkonzahn GMBH, Gais, Germany). The spherical compression test was used to determine fracture toughness, using 6 mmn diameter ceramic ball. Fracture load for damaging ceramic crown was recorded on a universal testing machine--Zwick, type 1464, with the speed of 0.05 mm/min. RESULTS: The results of this research introduced significant differences between fracture toughness of ceramic samples in every examined group. However, fracture toughness of crowns from both group was above 2000 N, what was double beyond a recommended value. The mean value of fracture toughness in the feather-edge group was 2090 N, and in shoulder group it was 2214 N. CONCLUSION: This research showed a high fracture toughness of zirconia crowns made on feather-edge preparation. The examined crowns showed a fracture resistance at a sufficient distance in relation to the minimum values of functional loads. Further research of functional loads of these crown is necessary, as well as research of marginal adaptation of cemented crowns and gingival inflammatory response.

Peripheral ostectomy with the use of Carnoy's solution as a rational surgical approach to odontogenic keratocyst: a case report with a 5-year follow-up.

INTRODUCTION: Odontogenic keratocyst (OKC) is a rare developmental, epithelial and benign cyst of the jaws of odontogenic origin with high recurrence rates. The third molar region, especially the angle of the mandible and the ascending ramus are involved far more frequently than the maxilla. The choice of treatment approach was based on the size of the cyst, recurrence status, and radiographic evidence of cortical perforation. Different surgical treatment options like marsupialization, decompression, enucleation, enucleation with Carnoy's solution, peripheral ostectomy with or without Carnoy's solution, and jaw resection have been discussed in the literature with variable rates of recurrence. CASE REPORT: We presented a 52-year-old male with orthokeratinized odontogenic keratocyst. Elliptical unilocular radiolucency located in the third molar region and the ascending ramus of the mandible, 40 x 25 mm in diameter with radiographic evidence of cortical perforation at the anterior ramus border of the mandible 20 mm in diameter, was registrated on orthopantomographic radiography. Surgical treatment included enucleation of the cyst and peripheral ostectomy with the use of Carnoy's solution and excision of the overlying attached mucosa. Postoperatively, no paresthesia in the inervation area of the inferior alveolaris nerve was registrated. Recurrences were not registrated within 5 years post-intervention. CONCLUSION: Treatment of odontogenic keratocyst with enucleation and peripheral ostectomy with the use of Carnoy's solution and excision of the overlying attached mucosa had a very low rate of recurrence. Radical and more aggressive surgical treatments as jaw resection should be reserved for multiple recurrent cysts and when OKC is associated with nevoid basal cell carcinoma syndrome (NBCCS). Following the treatment protocol in the management of OKC and systematic and long-term postsurgical follow-up are considered key elements for successful results.

The impact of thickness of resorbable membrane of human origin on the ossification of bone defects: a pathohistologic study.

BACKGROUND/AIM: A wide range of resorbable and non-resorbable membranes have been investigated over the last two decades. The barrier membrane protects the defect from ingrowth of soft tissue cells and allows bone progenitor cells to develop bone within a blood clot that is formed beneath the barrier membrane. The membranes are applied to reconstruct small bony defect prior to implantation, to cover dehiscences and fenestrations around dental implants. The aim of this study was to evaluate the influence of human resorbable demineralized membrane (RHDM) thickness on bone regeneration. METHODS: The experiment, approved by Ethical Committee, was performed on 6 dogs and conducted into three phases. Bone defects were created in all the 6 dogs on the left side of the mandible, 8 weeks after extraction of second, third and fourth premolars. One defect was covered with RHDM 100 micro thick, one with RHDM 200 micro thick, and the third defect left empty (control defect). The histopathological analysis was done 2, 4 and 6 months after the surgery. In the third phase samples of bone tissue were taken and subjected to histopathological analysis. RESULTS: In all the 6 dogs the defects treated with RHDM 200 micro thick showed higher level of bone regeneration in comparison with the defect treated with RHDM 100 micro thick and especially with empty defect. CONCLUSION: Our results demonstrated that the thicker membrane showed the least soft tissue ingrowths and promoted better bone formation at 6 months compared with a thinner one.

[Impact of dental implant insertion method on the periimplant epithelial seal--experimental study on dogs].

BACKGROUND/AIM: There is a controversial opinion among implantologists on the method of dental implantation that provides more favourable response of soft and bone tissues. The aim of this study was to pathohistologicaly compare the influences of one- and two-phase implant surgical methods on the periimplant epithelial tissues. METHODS: The experiment was performed on 10 dogs. Eight weeks following tooth extractions implants were inserted using one phase method on the right side of the mandible, and two-phase method on the left one. Three months after implantation the animals were sacrificed. Contact regions of epithelial and subepithelial tissues and implants were pathohistologicaly examined, the elements of analysis were scored and compared. RESULTS: Epithelial tissue was not found in the two samples of one-phase implants, while in the remainder of samples the structure of basal membrane was preserved, massive inflammatory infiltrate was found in one, and partial necrosis was found in three samples. Epithelial tissue was not found in the three samples of two-phase implants, in three samples the structure of basal membrane was intact, while in three remained samples the membrane could not be detected; moderate inflammatory infiltrate was found in four samples and massive inflammatory infiltrate in both two remained samples; tissue necrosis, which was observed in the half of the samples, was complete. In subepithelial gingival tissues around one-phase implants the number of blood vessels was increased in three samples, accompanied by the thickening and dilatation of vascular walls, proliferation of blood elements, altered vascular walls and inflammatory cell infiltrate was found in four samples. CONCLUSION: On the base of the analized characteristics of epithelial and subepithelial tissues in contact with dental implants, one-phase method of implantation showed a more favorable tissue response.

[Clinical efficacy of ampicillin in treatment of acute odontogenic abscess].

BACKGROUND/AIM: Antibiotics choice and the duration of their application in the therapy of acute odontogenic abscess is considered to be controversial. The aim of this study was to investigate the clinical efficacy of ampicillin in treatment of acute odontogenic abscess and to assess the antimicrobial susceptibility of the isolated bacteria in early phase of abscess development. METHODS: This study included 60 patients with acute odontogenic abscess who were surgically treated (extraction of teeth and/or abscess incision) divided into two groups, ampicillin group and surgical group (without antibiotic treatment). RESULTS: In the ampicillin group of patients treatment lasted on the average 4.67 days, while in the surgical group 6.17 days. A total of 78 bacterial strains were isolated from 60 patients. The most often bacteria were found to be Gram-positive facultative anaerobs (68/78). The most common bacteria isolated were Viridans streptococci (43/78). Susceptibility of isolated bacteria to ampicillin were 70.5%. CONCLUSION: Peroral use of ampicillin, after surgicel treatment in an early phase of dentoalveolar abscess development, statistically significantly reduced the time of clinical symptoms of acute odontogenic abscess in comparison to surgical treatment only. The isolated bacterial strains in an early phase of dentoalveolar abscess development showed a high sensitivity to ampicillin.