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This article reports the 4-year interim results of a multicenter study evaluating the clinical performance of the Osseotite dental implant. At 4 study centers, 485 Osseotite implants were consecutively placed in 181 patients (219 were placed in the mandible and 266 in the maxilla). A total of 355 implants were placed in posterior regions. Short implants (10 mm or less) represented 31.5% (n = 153) of all implants placed in this study. Patients were restored with 210 restorations, distributed as 123 short-span prostheses, 58 single-tooth replacements, 28 long-span prostheses, and 1 maxillary overdenture. At this 4-year interim evaluation, the mean time from implant placement to the most recent evaluation was 52.6 +/- 3.0 months, with a mean loading time of 43.3 +/- 3.8 months. Of the 485 implants placed, there have been 6 failures. All implant failures occurred prior to loading and were categorized as early implant failures. Five of the 6 failures occurred in the maxilla. Only one of the 153 short implants failed to integrate. Baseline radiographs were obtained at prosthesis connection. Radiographic analysis 1 year post-restoration showed a mean bone loss of 0.09 +/- 0.7 mm. From baseline to the end of the second year of function, an overall mean bone loss of 0.13 +/- 0.8 mm was recorded, indicating no additional bone was lost after the first year of implant function. At 4 years, the cumulative implant success rate for all implants placed in this study was 98.7%, with a 99.4% success rate in the posterior mandible and 98.4% success rate in the posterior maxilla. Results of this 4-year interim analysis indicate that this implant achieved a high success rate in posterior regions and that all failures with this implant in this patient population occurred prior to implant loading. When the clinical success of implants 10 mm or shorter was compared to that of implants greater than 10 mm in length, the shorter implants in this study performed similarly to longer implants.

Background/aims: This clinical trial aimed at comparing 2 different means of delivering chlorhexidine digluconate (CHX) in the oral hygiene phase during the 2 weeks following periodontal surgery., Method: 40 patients were randomly divided into 2 groups: A (using CHX mouthwash) and B (using CHX spray). Professional oral hygiene was carried out immediately before surgical operation. For 7 days after surgery, group A used CHX mouthwash and group B CHX spray on the teeth involved in the surgical procedure, while mechanical oral hygiene was maintained only on the teeth not involved surgically. After suture removal, on the 7th day, patients were allowed to perform mechanical oral hygiene also on surgical sites. Plaque index (PI) and stain index (SI) were evaluated on the 7th and 14th days after the operation., Results: In both groups, PI increased similarly with respect to the baseline in surgically involved teeth, being 0.25+/-0.41 (SD) and 0.15+/-0.26, respectively, in A and B, on day 7, and 0.14+/-0.23 (A) and 0.10+/-0.22 (B), on day 14. There was no significant difference between A and B on either day 7 or 14. On the contrary, SI increased significantly in respect to the baseline over the 14 days in group A at both involved and not involved sites, while it did not differ from the baseline in group B., Conclusions: The present results indicate that the efficacy of CHX spray in the post-surgical control of dental plaque is not different from that of CHX mouthwash. Tooth staining, on the contrary, was significantly lower in the group using CHX spray. The observed effects might be related to the way of delivering CHX and to the total dose administered, about 80% lower in group B in respect to A. Further studies are needed to validate the preliminary findings of the present study.

A human histologic study was conducted to compare the percentage of bone-to-implant contact (BIC) at 6 months for Osseotite and machined, commercially pure titanium implant surfaces. To eliminate potential influences caused by differences in bone density at different intraoral locations, 2 mm x 5 mm, threaded, 2-surfaced titanium implants were manufactured; 1 side received the Osseotite surface modification and the opposite side maintained a machined surface. In each of 11 patients, 1 test implant was placed in the posterior maxilla (Types III and IV bone) during conventional dental implant surgery. Following 6 months of unloaded healing, the conventional implants were uncovered, and the test implants and surrounding hard tissue were removed. Histologic analysis indicated that at 6 months of unloaded healing, the mean BIC value for the Osseotite surfaces (72.96% +/- 25.13%) was statistically significantly higher (P < 0.05) than the mean BIC value for the machined surfaces (33.98% +/- 31.04%). When the BIC values for the machined and Osseotite surface pairs were ranked from high to low based on the machined BIC value range of 93% to 0%, the upper 50th percentile (20 surface pairs) mean BIC value was 86.1% +/- 16.7% for the Osseotite surfaces and 60.1% +/- 18.3% for the machined surfaces. The lower 50th percentile (19 surface pairs) mean BIC value was 59.1% +/- 25.3% for the Osseotite surfaces and 6.5% +/- 10.8% for the machined surfaces. Differences between mean BIC values for the 2 surfaces in both the upper and lower 50th percentiles were statistically significant (P < 0.05). The results of this study indicate that in the poorer quality bone typically found in the posterior maxilla, a statistically significantly higher percentage of bone contacts Osseotite surfaces when compared to opposing machined surfaces on the same implant.

The objective of the present study was to compare the success rates of 2 different periapical surgical techniques, the traditional technique with rotary instruments and the ultrasonic technique, which uses ultrasonic retrotips. A longitudinal retrospective study was carried out on 302 apices (181 teeth) that had undergone periapical surgery. Surgical outcome was evaluated by 2 independent operators using standardized periapical radiographs. Each radiographic finding was classified into 1 of 4 groups: complete healing, incomplete healing, uncertain healing, and unsatisfactory outcome (failure). An SAS statistical analysis system was used for data management and analysis. Prognostic factors were determined by means of the Fisher exact test. Complete healing after 4.6 years (the average follow-up period) was observed in 68% of the teeth treated through the use of the standard technique and 85% of those treated through the use of the ultrasonic technique. The success rate increased as the follow-up period lengthened (68.4% at 2 years vs 80% at 6 years). The success rate was higher in maxillary (77.9%) than in mandibular (66.1%) teeth. A comparison between the retrofilling materials was not feasible because all teeth in the standard technique group were retrofilled with amalgam and all teeth in the ultrasonic group were retrofilled with Super-EBA.

Historically, the recommended time between placement and functional loading of machined-surface dental implants has been 3 months for the mandible and 6 months for the maxilla. However, such recommendations are a result of evaluating randomly chosen healing times during the initial phase of implant development and are based on the subsequent clinical outcome of either implant integration or mobility. In recent years, histologic and experimental studies have shown that specifically designed micro-topographic implant surfaces can result in increased bone-to-implant contact at earlier healing times than obtained with machined-surface implants. Histologic and clinical studies investigating early and immediate implant loading support the premise that implants can be placed into function earlier than previously recommended. With the development of specifically designed implant surfaces and the utilization of time-saving surgical (one-stage surgical protocol) and prosthetic (implant position indexing) techniques, patients are now being restored and returning to function sooner than previously thought possible. The purpose of this multicenter clinical investigation is to evaluate the efficacy of loading Osseotite dental implants (3i-Implant Innovations Inc., Palm Beach Gardens, Florida) at 2 months and to determine the effect of early loading on implant performance and survival. A total of 429 Osseotite implants were placed in 155 patients (87 females and 68 males; mean age 54.0 +/- 13.7 yr), at 10 study centers, and subsequently loaded 2.1 +/- 0.7 months following placement. A single-stage surgical protocol was followed, with implants indexed immediately or impressed 4 to 6 weeks following placement. Patient restorative treatments included placement of 83 single-implant provisional restorations and 129 splinted, two-, three-, and four-implant supported maxillary and mandibular provisional restorations. The mean time from prosthetic loading to the most recent follow-up evaluation was 10 +/- 1.3 months. Seven of the 429 implants did not integrate; of these, six were identified prior to loading and one was identified 1 month after loading. The cumulative implant survival rate was 98.5% at 12.6 months. The cumulative post-loading implant survival rate was 99.8% at 10.5 months. The preliminary results of this clinical investigation suggest that successful functional loading of the Osseotite dental implant is possible at 2 months following noncomplicated implant placement.

Using rotary instruments drilled bony cavities which differed in diameter and depth into a human jaw. X-rays were taken and developed employing a very precise and accurate technique to obtain high definition radiograph. From a careful study of these x-rays it was found that localized lesions in cancellous bone alone are difficult to visualize on x-rays, whereas they are easily noticeable when the cortical bone is involved.

In this study the authors investigated a group of front teeth, extracted because of the periodontal problems, into which an access cavity have been drilled at the point shown on an x-ray between two straight lines which start at the apex and are tangent to the pulp chamber. These teeth were then horizontally sectioned at the cement-enamel junction to see how much dental substance remained compared to a control group into which a traditional opening had been made through the palatal surface. The result show a greater conservation of dentin when the direct method of opening discussed herein was used.

This study investigated the frequency of periapical lesions following pulpal necrosis in vital teeth used as abutments in periodontal-prosthetic therapy. The study was conducted on a continuative series of 1000 teeth treated at least 2 years before the start of the investigation. 500 teeth were treated by specialist and 500 by general practitioners. The dental records of this sample were stored into a computer, analyzed and compared, and the chi-square index was calculated. Periapical lesions were found in 22.6% of the teeth. Maxillary incisors had the highest number of lesions (36.8%). The percentage of lesions increased as periodontal involvement became more severe (37.2%) with severe involvement as opposed to 18.5% with moderate involvement). The frequency of lesions was lower in the group of teeth treated by specialists than in the group treated by general practitioners (13.8% as opposed to 31.4%).

The Authors investigated a new kind of parallel-sided cylindrical posts used for anterior teeth (Triax--Whaledent Inc.--New York NY). Twenty-four freshly extracted maxillary incisors were selected for the study. Root canal therapy was performed and post-space prepared to receive the prefabricated post. Cementation of the posts was carried out using zinc phosphate cement and silver glass ionomer cement. Light cured composite, self curing composite and silver glass ionomer cement were used as cores materials. The specimens were examined under a scanning electron microscope. These new prefabricated posts luted with silver glass ionomer cement presented a gap at the dentin-cement and post interface similar to the cast posts luted with zinc-phosphate cement. The core material was in all the three different types of construction well adapted to the post head.

A throughfull literature review on vertical root fractures has been accomplished, analyzing in depth the causes of this frustrating clinical observation. Conclusions that can be of clinical importance have been reached.

To evaluate exposure to hepatitis B virus (HBV) in dental operators, we surveyed 297 students of the Dental School, University of Milano, and 526 dentists registered at the Italian Dental Association (A.M.D.I.) of Lombardia. Out of 297 students, 10.8% had one or more serologic markers of HBV infection; none was hepatitis B surface antigen (HBsAg) positive. No significant difference in seropositivity was detected among students in relation to sex, age, or possible risk factors investigated. Out of 526 practitioners, 2.3% were positive for HBsAg, and 37.3% were antibody positive. The seropositivity increased progressively with age and years of professional experience, reaching the highest proportion in dentists with 30 years or more of practice (79.3%). Of those who had suffered from clinical hepatitis during their curriculum, 81.1% were seropositive compared with 34.5% observed in dentists without a prior clinical history of viral hepatitis. The proportion of seropositive dentists did not vary significantly with a history of blood transfusion, size of their practice, presence or absence (or unawareness) of subjects at high risk for HBV infection among their patients. The seropositivity was significantly lower in dentists who routinely adopted mask and gloves (21.1%) compared with those who never and/or occasionally used such barriers (46.3%). The result of the study confirmed that hepatitis B does remain a significant hazard for dental professionals, hence immunization with hepatitis B vaccine should be delivered early in their employment.

A questionnaire concerning the acceptance of hepatitis B vaccination was mailed in April 1985 to 626 private dentists practicing in Milano and its county. Two hundred and twenty eight dentists (36.4%) filled out the questionnaire, 166 of them indicating their willingness to receive the vaccine. Between October 1985 and February 1986 we tested 241 practitioners for HBs antigen, anti-HBs and anti-HBc antibody, and SGPT (ALT) enzyme level. A 14.9% prevalence of HBV markers was found in the prevaccination testing. All persons with positivity for anti-HBs or HBsAg or with elevations of SGPT were excluded from the study (the latter temporarily). A few (42 or 20.9%) left spontaneously before the first dose of vaccine was administered. On the whole, 159 participants began the vaccination course. The proportion of vaccine recipients in dentists who indicated in the questionnaire their willingness to accept the vaccine and/or participated in a seroepidemiological survey performed in 1983 by some of us (85.1%) was significantly greater than that in the group of dentists who did neither (65.0%) (p less than 0.01). Educational effort appeared to be important to enroll and to counsel practitioners in implementing vaccination programme.