Peri-implantitis is considered to be a multifactorial process involving bacterial contamination of the implant surface. A previous study demonstrated that a combination of toluidine blue O (100 microgram/ml) and irradiation with a diode soft laser with a wavelength of 905 nm results in an elimination of Porphyromonas gingivalis (P. gingivalis), Prevotella intermedia (P. intermedia), and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) on different implant surfaces (machined, plasma-flame-sprayed, etched, hydroxyapatite-coated). The aim of this study was to examine the laser effect in vivo. In 15 patients with IMZ implants who showed clinical and radiographic signs of peri-implantitis, toluidine blue O was applied to the implant surface for 1 min and the surface was then irradiated with a diode soft laser with a wavelength of 690 nm for 60 s. Bacterial samples were taken before and after application of the dye and after lasing. The cultures were evaluated semiquantitatively for A. actinomycetemcomitans, P. gingivalis, and P. intermedia. It was found that the combined treatment reduced the bacterial counts by 2 log steps on average. The application of TBO and laser resulted in a significant reduction (P<0.0001) of the initial values in all 3 groups of bacteria. Complete elimination of bacteria was not achieved.

Positional inaccuracy is low in guided implant surgery, but may however significantly compromise implant esthetics in the anterior maxilla.

One third of all biopsies adjacent to crowns of unerupted teeth had significant lesions. Over a 6 year period, 2646 pericoronal lesions were biopsied when impacted teeth were removed from patients aged 18-89 yrs. Over 90% were from third molars, and most of the others were from canines. The biopsies constituted 7.6% of all oral biopsies sent to a US university laboratory. Most reports (67%) were of follicular tissue. Lesions diagnosed were: dentigerous cyst (28%), dentigerous cyst with mucous cell prosoplasia (3%), odontogenic keratocyst (2.7%), odontoma (0.7%), ameloblastoma (0.5%), calcifying odontogenic cyst (0.23%), carcinoma (0.23) and odontogenic myxoma (0.04%). From the 5th decade onwards, about half the biopsies were of pathological lesions. Dentigerous cyst was the commonest lesion up to age 70, but other lesions were more frequent later. A following critical discussion states that the findings justify histopatho-logical examination of perifollicular tissue from all impacted teeth removed after age 30. Five years of aftercare of implant-retained mandibular overdentures and conventional dentures Visser A, Geertman ME et al. J Oral Rehabil 2002; 29: 113-120 Endosseous implants were substantially better than the transmandibular implant system. In 2 centres in the Netherlands, 222 patients (6% had dropped out) were followed up after 6 categories of complete prosthodontic treatment for severely resorbed mandibular ridges. Most of the patients were also evaluated on a 5 point scale for comparing implants. During 5 years' follow-up, in patients with mandibles of 8-15 mm height, implant loss was 5% for 57 overdentures on 2 endosseous implants, and 29% for 27 with transmandibular implants and overdenture, while implant insertion was postponed for 30% of those with conventional dentures: these patients could opt for implants after 1 year. In patients with mandibles of 16-25 mm height, implant loss was 17% for 30 overdentures on 2 endosseous implants, while in 11% of 27 who received vestibuloplasty and complete denture and I M P L A N T P R O S T Failure was about 10%, and most occurred within 2 years, with a surprising trend towards greater mandibular loss. This study followed 97% of a group of 76 implants (59 maxillary) in 71 patients for 4-10 yrs (mean 5.5). This is a lower drop-out rate than in other studies. Eleven implants were inserted immediately after extraction, 17 were delayed to 6-8 weeks post-extraction and 48 were placed in normal edentulous ridge tissues. Guided bone regeneration was added to 14 implant insertions and hydroxyapatite augmentation to 5, and both these adjuncts were used in one case. Kaplan-Meier survival probabilities were 96% for the maxilla and 80% for the mandible after 120 months (NS). Five implants were lost, 4 within 2 years. With 12 implants, abutment screws loosened during the study, but this was resolved in 5 where a electronic torque controller was applied at 32 Ncm. Mean peri-implant bone loss was 1.8 mm in the maxilla and 1.3 mm in the mandible, and 15 implants showed more...

This study was designed to examine the effects of low-energy laser irradiation on osteocytes and bone resorption at bony implant sites. Five male baboons with a mean age of 6.5 years were used in the study. Four holes for accommodating implants were drilled in each iliac crest. Sites on the left side were irradiated with a 100 mW low-energy laser (690 nm) for 1 min (6 Joule) immediately after drilling and insertion of four sandblasted and etched (Frialit-2 Synchro) implants. Five days later, the bone was removed en bloc and was evaluated histomorphometrically. The mean osteocyte count per unit area was 109.8 cells in the irradiated group vs. 94.8 cells in the control group. As intra-individual cell counts varied substantially, osteocyte viability was used for evaluation. In the irradiated group, viable osteocytes were found in 41.7% of the lacuna vs. 34.4% in the non-irradiated group. This difference was statistically significant at P < 0.027. The total resorption area, eroded surface, was found to be 24.9% in the control group vs. 24.6% in the irradiated group. This difference was not statistically significant. This study showed that osteocyte viability was significantly higher in the samples that were subjected to laser irradiation immediately after implant site drilling and implant insertion, in comparison to control sites. This may have positive effects on the integration of implants. The bone resorption rate, in contrast, was not affected by laser irradiation.

Copy-Abutments for immediate restoration of implants in the esthetic zone show satisfactory long-term esthetic outcomes.