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Purpose: For dental implants to be successful, osseointegration must occur, but it is unknown how much time must pass for osseointegration to be established. Preclinical studies suggested that titanium implants with a sandblasted and acid-etched (SLA) surface were more osteoconductive and allowed more rapid osseointegration than machined or turned implant surfaces. The hypothesis of this study was that implants with an SLA surface could be loaded in half the conventional healing time of machined-surface implants and that, after loading, the implants would be successful for 5 years., Materials and Methods: A prospective multicenter clinical study was conducted with 439 implants placed in native bone in 135 edentulous and partially edentulous patients. Abutments were attached to the implant with 35 Ncm of torque without countertorque after 6 weeks in type I to III bone and after 12 weeks in type IV bone. The patients were carefully evaluated for 5 years., Results: Most implants were placed in nonsmoking, nondiabetic patients with a mean age of 55 years (range, 21 to 82 years). Eighty percent of the implants were 10 or 12 mm long, 96% had a diameter of 4.1 mm, and 78% were placed in type II or III bone. Patients maintained good oral hygiene and were satisfied with the restorations. Four implants failed, and one implant was deemed unsuccessful between surgery and the 1-year postloading visit. No implants failed or were unsuccessful in subsequent years. The cumulative survival and success rates for 385 implants in 120 patients after 5 years were 99.1% and 98.8%, respectively., Conclusion: Implants with an SLA surface can be restored in 6 weeks for type I to III bone and 12 weeks for type IV bone. Furthermore, they can be maintained after loading for 5 years with very high success and survival rates.

Purpose: The aim of this prospective cohort study was to determine the 5-year implant survival and success rates associated with early loading (6 weeks after nonsubmerged placement) of sandblasted and acid-etched (SLA) Straumann implants in the edentulous mandible. A secondary objective was to determine the peri-implant tissue response and measure alterations in peri-implant crestal bone levels., Materials and Methods: SLA implants were placed and primarily loaded 6 weeks later with 35 Ncm during abutment placement. The peri-implant bone and mucosal conditions of the participants were monitored radiographically and clinically over a 5-year period., Results: Fourteen patients received 60 implants. Thirteen patients and 54 implants were examined at the 5-year appointment. Two of 60 implants failed during the healing period, and four implants were lost during follow-up and considered as dropouts. The remaining implants showed favorable clinical and radiographic findings and were considered successfully integrated at the 5-year examination. The mean loss of crestal bone height after 5 years was 0.77 mm (SEM 0.09). This resulted in a 5-year cumulative success rate of 96.7%., Conclusion: In this prospective study, the early loading of Straumann implants with the SLA surface in the edentulous mandible after a healing time of 6 weeks provided successful osseointegration with high predictability. Successful integration was maintained for 5 years.

Background: Intermediary filaments are involved in cell motility and cancer progression. In a variety of organs, the expression of distinct intermediary filaments are associated with patient prognosis. In this study, we seeked to define the prognostic potential of cytokeratin and vimentin expression patterns in squamous cell carcinomas (SCC's) of the oral cavity., Methods: 308 patients with histologically proven and surgically treated squamous cell carcinomas of the oral cavity were investigated for the immunohistochemical expression of a variety of intermediary filaments including high- and low-molecular weight cytokeratins (Ck's), such as Ck 5/6, Ck 8/18, Ck 1, CK 10, Ck 14, Ck 19 and vimentin, using the tissue microarray technique. Correlations between clinical features and the expression of Cytokeratins and vimentin were evaluated statistically by Kaplan-Meier curves and multivariate Cox regression analysis., Results: The expression of Ck 8/18 and Ck 19 were overall significantly correlated with a poor clinical prognosis (Ck 8/18 p = 0.04; Ck19 p < 0.01). These findings could also be reproduced for Ck 8/18 in primary nodal-negative SCC's and held true in multivariate-analysis. No significant correlation with patient prognosis could be found for the expression of the other cytokeratins and for vimentin., Conclusion: The expression of Ck 8/18 in SCC's of the oral cavity is an independent prognostic marker and indicates a decreased overall and progression free survival. These results provide an extended knowledge about the role of intermediary filament expression patterns in SCC's.

Objectives: The delivery of an adequate amount of blood to the tissue capillaries for normal functioning of the organ is the primary purpose of the vascular system. Preserving the viability of the soft tissue segment depends on the soft tissue incision being properly designed in order to prevent impairment of the circulation. A knowledge of the course of the vessels as well as of their supply area are crucial to the decision of the incision. The aim of this study was to visualize the course of the arteries using different techniques, to perform macroscopic- and microscopic analyses, and to develop recommendations for incisions in implant dentistry., Material and Methods: The vascular systems of seven edentulous human cadavers were flushed out and filled with either red-colored rubber bond or Indian ink and formalin mixture. After fixation a macroscopic preparation was performed to reveal the course, distribution and supply area of the major vessels. In the area of the edentulous alveolar ridge specimens of the mucosa were taken and analyzed microscopically., Results: The analyses revealed the major features of mucosal vascularization. The main course of the supplying arteries is from posterior to anterior, main vessels run parallel to the alveolar ridge in the vestibulum and the crestal area of the edentulous alveolar ridge is covered by a avascular zone with no anastomoses crossing the alveolar ridge., Conclusion: The results suggest midline incisions on the alveolar ridge, marginal incisions in dentated areas, releasing incisions only at the anterior border of the entire incision line, and avoidance of incisions crossing the alveolar ridge.

Aim: Different surgical approaches for the open treatment of mandibular condylar fractures are described in the literature. We evaluated the morbidity of the transparotidean approach in a prospective study over 5 1/2 years., Patients and Methods: A total of 48 patients with 52 condylar neck fractures class II and IV according to the Spiessl and Schroll classification were treated by a transparotidean approach. Rigid internal fixation was performed by means of miniplate fixation. After surgery, no mandibulomaxillary fixation was performed. The occurrence of surgical and functional complications was documented both during hospitalization and 1, 3, 6 and >9 months after surgery., Results: In none of our patients were major problems in wound healing such as infection of the fracture site observed. At the beginning of the study, in four cases a fistula of the parotid gland was seen within the initial days after surgery; after careful wound closure of the parotid capsula in the following operations, no further complications involving fistulas were observed. Signs of temporary palsy of the facial nerve caused by the hooks occurred in ten (19.6%) of all patients but was completely reversible within the first 6 months after the procedure. One patient suffered temporarily from a minimal malocclusion and two patients from symptoms of the temporomandibular joint 6 months postoperatively. In three patients we observed miniplate fractures without consecutive dysfunction of the TMJ or malocclusion., Conclusion: Open reduction and rigid internal fixation of condylar neck fractures by transparotidean approach is a recommendable procedure in class II and IV fractures. With the advantages of minimal tissue alteration and rare complications on the one hand and sufficient exposure of the fracture site on the other hand, this technique has been established as a standard procedure in treating condylar neck fractures by open reduction.

Background: Segmental resection of the mandibula in oral cancer surgery leads to both functional and aesthetic problems. The decision to preserve or resect the mandible depends on the vicinity of the lesion to the bone. Consequently, based on the rules of safety margins to all planes that are recommended for soft tissues, each lesion that is closer than 10 mm to the mandible needs resection of the bone., Patients and Methods: To establish data-based treatment modalities, a retrospective study was initiated and the results from all preoperative staging investigations of 152 patients with intraoral squamous cell carcinoma who underwent continuity or marginal resection of the mandible were evaluated. The histological outcome of the resected bone was compared to the staging results. Functional rehabilitation and long-term follow-up including survival rates were evaluated. The study reports on typical complications following segmental resection such as fracture of the reconstruction plate and demonstrates experiences with secondary microsurgical reconstructive surgery., Results: Mainly in cases of stage T1 and T2 carcinomas which are closer than 10 mm to the bone and clinically do not show any infiltration to the mandible, a marginal resection seems to be adequate. The decision about the extension of mandibular resection can be based on intraoperative cross sectional investigation of the periosteum. The survival rate of patients with intraoral carcinomas close to the mandible who underwent marginal mandibulectomy seems to be the same as in cases of continuity resection. A more conservative management of mandibular resection seems to be adequate and a data-based concept to standardize therapy of mandibular resection is presented.

ITI dental implants are available with two bone-anchoring surfaces, a titanium plasma-sprayed (TPS) surface, and a recently introduced sandblasted and acid-etched (SLA) surface. Cell culture and animal tests demonstrate that the SLA surface stimulates bone cell differentiation and protein production, has large amounts of bone-to-implant contact, and results in large removal torque values in functional testing of the bone contact. As a result of these studies, a prospective human clinical trial was initiated to determine whether the 4.1 mm diameter SLA ITI solid screw implants could be predictably and safely restored as early as six weeks after implant placement surgery. The protocol restricted the use of the reduced healing time to a) healthy patients with sufficient bone volume to surround the implant, and b) those patients who had good bone quality (classes I-III) at the implant recipient site. Patients with poorer bone quality (class IV) did not have restorations until 12 weeks after implant placement. The clinical trial is an ongoing multicenter trial, with six centers in four countries, and with follow-up over five years. The primary outcome variable was abutment placement with a 35 Ncm force, with no countertorque and no pain or rotation of the implant. A secondary outcome was implant success, as defined by no mobility, no persistent pain or infection, and no peri-implant radiolucency. To date, 110 patients with 326 implants have completed the one-year post-loading recall visit, while 47 patients with 138 implants have completed the two-year recall. Three implants were lost prior to abutment connection. Prosthetic restoration was commenced after shortened healing times on 307 implants. The success rate for these implants, as judged by abutment placement, was 99.3% (with an average healing time of 49 days). Life table analyses demonstrated an implant success rate of 99.1%, both for 329 implants at one year and for 138 implants at two years. In the 24-month period after restoration, no implant losses were reported for the 138 implants. These results demonstrate that, under defined conditions, solid screw ITI implants with an SLA endosseous surface can be restored after approximately six weeks of healing with a high predictability of success, defined by abutment placement at 35 Ncm without countertorque, and with subsequent implant success rates of greater than 99% two years after restoration.

A total of 124 patients on oral anticoagulation therapy with coumarin were treated by orosurgical procedures and entered into a study to determine the hemostatic efficiency of different methods. The therapeutic anticoagulation level was determined in accordance with the recommendations of the American Heart Association (low risk: 2.0 < INR < 3.0; high risk: 2.5 < INR < 3.5) and maintained during treatment. In one group, the alveoli were treated with collagen, in a second group a mouthrinse regime with tranexamic acid was implemented. Twenty-three patients had to be excluded because anticoagulation levels differed from the recommended values. The group treated with collagen included 31 patients, the group with tranexamic acid mouthwashes, 32 patients. A third group was analyzed in which a controlled change in the anticoagulation level had been performed and all treated alveoli had been covered by mucosal flaps (n = 38); they were compared to the other two groups. The surgical proceedings were outlined precisely. Patients treated with collagen had a bleeding rate of 19%, patients with tranexamic acid mouthwash 6%, and those treated with mucosal flaps 40%. The data were not suited for statistical evaluation, they were objected to a descriptive analysis: the confidence intervals were determined by tables for binomial distributions. These did confirm the difference in the frequency of bleeding for the tranexamic acid and mucosal flap groups.

The basic surgical principles governing the placement of ITI implants are based on research-oriented developments in harmony with evidence-based and outcome-oriented clinical procedures. In the past 15 years, the range of implant indications has been significantly widened, and partially edentulous patients clearly represent the majority of patients seeking treatment with dental implants today. An important aspect of the successful rehabilitation of patients with ITI implants is the careful selection of implant candidates with respect to systemic and local risk factors. These factors are presented based on current knowledge. Today, solid-screw implants in various screw dimensions and neck configurations comprise the ITI Dental Implant System. These different implant types are necessary to handle the full range of implant indications, in particular in partially edentulous patients. The main clinical factors are presented for the selection of the appropriate implant type, length and diameter. These implants are utilized both in a non-submerged and in a submerged approach. The main goal of surgical therapy is low trauma and the least demanding surgical procedure for patient and clinician to optimize the cost-effectiveness of implant therapy. Hence, a non-submerged approach is preferred in all sites without esthetic priority, such as in fully edentulous patients or in posterior sites of partially edentulous patients. These indications clearly represent the majority of implant patients. In esthetic sites, a submerged approach is utilized to satisfy the specific esthetic demands. The possibility to successfully utilize short implants (6 and 8 mm) and a reduced healing period of 3 months are further advantages of ITI implants due to favorable properties of the rough TPS surface. With the introduction of the microrough SLA surface, a reduction of the healing period to 6 weeks facilitates further progress towards simplification of implant therapy. In summary, the ITI Dental Implant System represents a scientifically well-documented, complete implant system for the treatment of fully and partially edentulous patients, offering straightforward surgical concepts based on predictable treatment outcome and excellent cost-effectiveness.

The use of ITI implants for rehabilitation of the edentulous patient has shown predictable results not only in the standard sites but also in cases of advanced alveolar ridge atrophy. Preoperative analysis, including clinical and radiological evaluation, implant selection, and determination of implant number and distribution in the edentulous maxilla and mandible, is described in this article. The surgical procedures used in standard sites are presented, the benefits of a nonsubmerged surgical approach in these cases are emphasized, and a protocol for postoperative management is recommended. Augmentation procedures in advanced osseointegration surgery call for submerged ITI implants when a simultaneous approach is chosen. Several types of advanced implant surgery that can be used are described, including membrane technique, sinus lift procedures, vertical ridge augmentation with iliac bone grafts, and correction of sagittal jaw relationship.

In ten patients with craniosynostoses resorbable plates and screws (Lactosorb) consisting of poly-L-lactic acid (82%) and poly-glycolic acid (18%) were used to stabilize the segments after frontoorbital advancement. As our experience increased, an exact adaptation of the plates and simple handling proved to be possible. The plates were stable enough to retain a favorable functional and aesthetic result after redraping the soft tissue envelope. In one patient with Chotzen's syndrome the intended use of the resorbable material was abandoned: the thin osseous structures did not offer enough primary stability to the high pitch of the screws. During an observation period of up to 21 months no infection, exposure, instability or dislocation was observed. The clinical use of the resorbable material in frontoorbital advancement proved to be a stable method of segment fixation if the bone was of sufficient thickness. These promising preliminary results will have to observed in a larger group and over a longer period of time.

Purpose: Mandibular fractures are common facial injuries. Classifications are diverse and sometimes correlated with specific treatment modalities. Osteosynthesis using plate and screws is the standard method of fracture treatment. To evaluate the outcome of such fracture management in our clinic, we developed a numeric scoring system for mandibular fractures and investigated the relationship between the scoring of the fracture being treated and the incidence of complications after surgical treatment., Patients and Methods: Seventy-six adult patients treated over a 2-year period were evaluated, and the fractures were classified using the mandibular trauma score. This score was based on clinical and radiologic evaluation of each fracture line and ranks from 0 to 15 points. Osteosynthesis was performed using the AO plate systems. Patients were followed-up postoperatively for the presence of complications., Results: During the 2-year period, 76 patients with 134 fractures underwent plate osteosynthesis. Fracture scoring indicated a homogeneous distribution between uncomplicated and severe fractures. The incidence of complications increased with the fracture severity, assessed by the fracture score index. Severe fractures showed fewer complications when treated with a rigid plate system, whereas low-score fractures showed better results when treated with less rigid systems., Conclusions: The numeric scoring system for mandibular fractures allows an objective and standardized assessment of the degree of severity of a fracture and may facilitate decisions about the use of specific treatment modalities.

A method for treatment of sagittal discrepancy in edentulous patients is described, which includes simultaneous maxillary repositioning by means of a Le Fort I osteotomy and placement of endosseous implants. The technique of mandibular setback using the sagittal osteotomy of the mandible according to Obwegeser-Dal Pont's method and placement of implants in patients with extreme class III relationships is also presented. We outline the importance of thorough diagnosis, model surgery and its transfer at the time of the operation. The study of 12 consecutively treated patients with a follow up of 4.2 years showed functionally and esthetically good results after combined surgical and implantological treatment.

The surgical treatment of different types of mandibular fractures requires complex consideration. It can be realised not by the application of only one treatment concept, e.g. miniplates or rigid osteosynthesis, but a differentiated indication of every stability system depending on the individual requirements in each case. Basing on the results of clinical studies the contemporary concept applied at Münster in treatment of mandibular fractures is presented.

Healthy human periodontal and peri-implant (ITI Bonefit) keratinized gingival tissues were studied immunohistochemically to evaluate the possible presence of structural differences in the extracellular matrix protein localization. Collagen types I, III, IV, and VII and fibronectin showed similar distribution in these tissues. Compared to the periodontal tissues, collagen type V was localized in higher amounts in the lamina propria of the peri-implant gingival tissues. Collagen type VI stained the periodontal tissues as a delicate microfibrillar network contrasting to the not well-stained peri-implant gingival tissues. The data show that structural differences between these tissues are present. The structural differences may be responsible for the defense of peri-implant keratinized gingival connective tissues to bacterial penetration, because of the high amount of the collagen type V component, which is responsible for the higher collagenase stability.

Ceramic restorative materials offer certain advantages over metal-acrylic and metal-ceramic restorations, including low plaque accumulation, corrosion resistance, nonallergenic properties, and excellent aesthetic results. A new ceramic material with a high aluminum content has been recently developed. It addresses the problem of some other materials which absorbed saliva in the oral environment and caused microcracks, rendering them unsuitable for multi-unit suprastructures. The learning objective of this case report is to describe the clinical and laboratory procedures for fabrication of the all-ceramic implant-supported suprastructures for an edentulous patient after orthognathic surgery and the placement of associated endosseous oral implants.

Purpose: This study was designed to determine the reliability of DNA analysis in predicting outcome of patients with colorectal carcinoma and compare the prognostic efficacy of DNA analysis using two parameters vs. a single parameter., Methods: Two hundred forty-eight patients with colon and rectal carcinoma were entered in the study over a period of 84 months. Thirty-one percent of carcinomas were found in the rectum. A total of 23.6 percent of cancers were found in the sigmoid colon. Majority of the patients were 60 years or older. Male to female ratio was equal. The colon bearing carcinoma was sent in a fresh state after resection for flow cytometry and DNA analysis. In this study, analysis was made, comparing two parameters (aneuploidy and S-phase fraction over 20 percent) with single parameters (aneuploidy) for staging and as a prognostic indicator in patients with colon and rectal carcinoma., Results: The combined presence of aneuploidy and S-phase fraction over 20 indicated a poorer prognosis in patients with colon and rectal carcinoma. The prediction of patient outcome was more accurate with DNA analysis using two parameters than using a single parameter alone (P value = 0.00003)., Conclusion: In our analysis, the odds of survival are over 3.7 times greater for aneuploidy than aneuploidy plus S-phase fraction over 20 percent.

In an experimental animal study using rabbits, growth phenomena were simulated which are comparable to craniosynostosis in humans. The radiological and histological findings after surgical management of these artificial craniosynostosis by means of strip ostectomy or radical ostectomy were compared with the findings obtained in control animals. Following strip ostectomy, bone defects were rapidly filled by the formation of suture-like structures. After radical ostectomy, structures consisting of connective tissue dispersed among islands of ossification were preserved over a considerable period of time, making it possible for the calvarium to adapt to the fast-growing brain. In contrast to strip ostectomy, after radical ostectomy growth of both the neurocranium and the viscerocranium, as well as the total sagittal growth of the skull, were almost identical to the corresponding growth in the control animals.

Radiographic examination is of particular importance prior to the placement of dental implants, especially when the alveolar ridge is severely atrophied. Accurate assessment of the amount of residual bone can be improved with tomography. A method is described which utilizes templates and marking aids to facilitate the correct positioning of the jaws so as to obtain a true cross-section of the alveolar ridge at the intended implant sites. The same template can be used to determine the location and angulation of the implant at surgery.

In cases of advanced alveolar ridge atrophy, when the bone available for endosseous implants is not sufficient, endosseous implants are combined with augmentation of the alveolar ridge by means of autologous bone transplants. Depending on the type of atrophy found, the authors use three different surgical procedures: onlay technique, sandwich technique and alveolar extension technique. In all cases functional loading of the implants was performed by way of an entirely implant-supported bridgework. Results to date indicate that initial postoperative resorption is followed by a virtual standstill once the implants have been loaded.

During surgical removal of impacted third molars, the concentration of Penicillin G was determined in the compact bone of the mandible. Fifteen patients received 5 million IU and 15 received 10 million IU of Penicillin G intravenously as a single dose before surgery began. In both groups concentrations of penicillin with a bactericidal effect on most pathogenically relevant oral bacteria were detected during osteotomy. Taking into account the considerable interindividual variation, the one-shot application of 10 million IU of Penicillin G was more effective in certain cases than the 5 million IU dose. The factors influencing the decision on the high single-dose application include expected length of operation, body weight, kidney function, and infusion period. Assuming that in intraoral osteotomies the bone becomes contaminated with bacteria that are highly sensitive to penicillins, the results indicate that preoperative infusion of Penicillin G could be an effective method of preventing wound infection.

A squamous cell carcinoma developed in a 66 year old patient in the region of a traumatically caused oro-antral fistula that has persisted for 40 years. The clinical course and histological findings are presented. Based on the few case reports in the literature the occurrence of malignancies in chronic traumatic fistulae is discussed. Reference is also made to causal relationships between such a fistula and malignancy under the aspect of forensic medical consultations.

This case report presents a 43-year-old woman who was not happy with her complete dentures both from the functional and the esthetic point of view. The combined therapy of orthognathic surgery, insertion of endosteal oral implants and the loading with all-porcelain cantilevered bridges made out of In-Ceram is reported.

In an experimental study an attempt was made to compare the effect of the tetrachlorodekaoxygen anion complex (TCDO) with an aqueous KCl/CaCl2 solution of a defined molar concentration in hydrogel on the basis of skin defects, irradiated skin defects, and necrectomized burns of the skin of the back of naked euthymic guinea pigs. The wound healing of the irradiated skin defects and the necrectomized burns was found to be generally delayed. The use of the Kcl/CaCl2 solution in hydrogel, however, brought about a faster repair of the defects than the application of TCDO.

Besides uni- and multilocular jaw cysts the Gorlin-Goltz-syndrome shows other characteristic radiographic findings which help to ensure diagnosis. These are particularly calcification of the falx cerebri and a so called "bridging" between processus clinoideus anterior und posterior of the sella turcica. The importance of early diagnosis is stressed.