Renzo Guarnieri

The impact of a laser-microtextured collar on crestal bone level and clinical parameters under various placement and loading protocols.

PURPOSE Physical attachment of connective tissue fibers to a laser-microtextured (8- and 12-μm grooves) surface on the collar of an implant has been demonstrated using human histology. Related clinical research has suggested that this microtextured surface may help to decrease initial bone loss after implant placement. The aim of this retrospective study was to compare crestal bone heights and clinical parameters between implants with laser-microtextured and machined collars placed and loaded with different protocols. MATERIALS AND METHODS This study evaluated 300 single implants in 300 patients (155 men, 145 women; mean age: 49.3 years; range: 45 to 75 years). One hundred sixty implants with laser-microtextured collars (L) and 140 with machined collars (M) were used. Implants were grouped into the treatment categories of immediate placement, delayed placement, immediate nonocclusal loading, and delayed loading. For all groups, crestal bone level, attachment level (CAL), Plaque Index, and bleeding on probing were recorded at baseline and 6, 12, and 24 months after loading with the definitive restoration. RESULTS Nine implants were lost (four L and five M). The type of implant and timing of placement and loading showed no significant influence on survival rates. A mean CAL loss of 1.12 mm was observed during the first 2 years in the M group, while the mean CAL loss observed in the L group was 0.55 mm. Radiographically, L group implants showed a mean crestal bone loss of 0.58 mm, compared to 1.09 mm for the M group. CONCLUSION A laser-microtextured surface on the implant collar may mitigate the negative sequelae associated with peri-implant bone loss, regardless of the placement and loading protocols used.

Single‐Tooth Replacement in the Anterior Maxilla by Means of Immediate Implantation and Early Loading: Clinical and Aesthetic Results at 5 Years

BACKGROUND The hypothesis of the present study was that the early loading of single implants-supported restorations, replacing single extracting teeth in the anterior region of the maxilla in case of fresh extraction sockets with residual hard and soft tissue preservation, could be a successful procedure. METHODS Twenty-one implants were placed into maxillary anterior fresh extraction sockets using a flapless technique. Temporary restorations, which were fabricated from the impression taken immediately after implant placement, were connected within 2 weeks. These temporary restorations were adjusted in order to avoid any direct occlusive contacts. Six months after implantation, the implants were restored with single-teeth all-ceramic prostheses. Patients were followed for 5 years. Radiographic and clinical examinations were made at baseline, at time of definitive crowns delivery, and each subsequent year. Survival rate, cortical bone responses, and peri-implant mucosal responses were evaluated. RESULTS One implant was lost at 6 months. Clinical osseointegration of 20 implants was achieved (95.2% implant survival rate after 5 years) with minimal gingival recession and papillae preservation. The mean change in marginal cortical bone level was 0.40 mm at 6 months and 0.83 mm at 5 years. CONCLUSIONS Within the limit of the present study, the data indicate that, under a strictly controlled oral hygienic regimen, single-tooth implants, with immediate placement and early loading protocol, may be used in anterior maxillary fresh extraction sockets with residual hard and soft tissues preservation, if patients are selected carefully and if high primary stability is strictly followed.

Immediate versus Delayed Treatment in the Anterior Maxilla Using Single Implants with a Laser-Microtextured Collar: 3-Year Results of a Case Series on Hard- and Soft-Tissue Response and Esthetics.

PURPOSE To compare peri-implant marginal bone loss, soft tissue response, and esthetics following single immediate implant treatment (IIT) and delayed implant treatment (DIT) in the esthetic zone of the maxilla in well-selected patients. MATERIALS AND METHODS Adequate bone volume and ideal soft tissue level/contour were considered requirements for implant therapy, with additional prerequisites for IIT of residual alveolar bone wall integrity and a thick gingival biotype. IIT included immediate placement and provisionalization, while DIT included extraction socket preservation followed by implant placement and provisionalization 4 months later. Cortical bone levels and peri-implant mucosal conditions were evaluated at regular intervals. The esthetic outcome was objectively rated after 3 years using the pink esthetic score (PES) and white esthetic score (WES). RESULTS Twelve patients received an immediate Laser-Lok® implant, and 13 patients received a delayed Laser-Lok® implant. No significant differences were found between the study groups regarding survival rate (100%). The mean bone level from the implant/abutment interface was 0.35 ± 0.18 mm for IIT and 0.42 ± 0.21 mm for DIT after 3 years (p > 0.05). Mesial and distal papillae remained stable over time in DIT. A tendency for regrowth of mesial and distal papillae was found following IIT (p < 0.05). Midfacial soft tissues remained stable over time following DIT and IIT. CONCLUSIONS Within the limitations of this study (e.g., small sample size, short follow-up duration), the results suggest that regarding success rate, hard/soft tissue responses, and esthetics, DIT and IIT with single Laser-Lok® implants in the anterior maxilla are comparable and predictable options for well-selected patients.

Influence of a Laser-Lok Surface on Immediate Functional Loading of Implants in Single-Tooth Replacement: Three-Year Results of a Prospective Randomized Clinical Study on Soft Tissue Response and Esthetics.

The purpose of the present prospective randomized study was to evaluate the influence of Laser-Lok microtextured surface on soft tissue peri-implant parameters and esthetics around immediate, functionally loaded implants for single-tooth replacement in the esthetic zone. This study included 77 patients divided into two groups based on different implants used: the control group had BioHorizons tapered internal non-Laser-Lok-type implants (NLL; n = 39) and the test group had BioHorizons tapered internal Laser-Lok-type implants (LL; n = 39). Outcome measures were survival, radiographic marginal bone-level changes, soft tissue parameters, and esthetics. One implant was lost in the test group and one in the control group, for a total survival rate of 96.1% after 3 years. Radiographically, mean crestal bone loss ± standard deviation was 0.59 ± 0.27 mm in the LL group compared with 1.17 ± 0.31 mm in the NLL group. A mean gain in papilla level of 0.41 ± 0.34 mm and 0.17 ± 0.36 mm was observed in the LL and the NLL groups, respectively, while the level of the midfacial peri-implant mucosa remained stable in both groups with no statistically significant differences (0.08 ± 0.42 mm for the LL group vs 0.06 ± 0.36 mm for the NLL group). The mean probing depth values in the LL and NLL groups were 0.58 ± 0.2 mm and 1.89 ± 0.3 mm, respectively. Within the limitations of this study, it was demonstrated that the clinical and esthetic outcome of immediate functional loading was more favorable for LL implants than for NLL implants.

Clinical, radiographic, and esthetic evaluation of immediately loaded laser microtextured implants placed into fresh extraction sockets in the anterior maxilla: a 2-year retrospective multicentric study.

Objectives:To assess the clinical, radiographic, and esthetic outcomes of implants with a laser microtextured collar placed in the anterior region of the maxilla at the time of tooth extraction and immediately temporized. Methods:Forty-six Tapered Internal Laser-Lok BioHorizons implants were immediately placed and immediately restored with nonfunctional loading in 46 patients (24 men and 22 women) with a thick gingival biotype, ideal gingival level/contour, and postextraction intact walls. Survival rate, cortical bone loss, and periimplant mucosal responses were evaluated at 6, 12, and 24 months. Results:Survival rate was 95.6%. Mean mesial and distal marginal bone loss, 24 months after installation, were 0.58 mm (SD = 0.53; range, 0.17–1.15) and 0.57 mm (SD = 0.70; range, 0.42–1.10), respectively. A mesial and distal papilla regrowth mean of 1.8 and 1.5 mm, respectively, were found. The midfacial soft tissue levels showed 0.12 mm of mean recession after 24 months. Conclusion:Immediate implants with a laser microtextured surface restored at the day of surgery, may be considered as a predictable procedure in terms of implant survival and hard and soft tissue remodeling.

A double-blind randomized trial comparing implants with laser-microtextured and machined collar surfaces: Microbiologic and clinical results

PURPOSE The purpose of this study was to compare the clinical outcome of and determine the differences in periodonto-pathogenic microbiota around two types of implant collar surfaces: laser-microtextured (test) vs machined (control). MATERIALS AND METHODS Seventeen patients (11 periodontally healthy, and 6 periodontally compromised) were selected to receive the two different implants, placed randomly, in two edentulous sites. Six months following the surgical placement of the dental implants, subgingival plaque samples were collected using paper points from the peri-implant sulcus and from the sulcus of an adjacent tooth. The presence of five putative periodontal pathogens, namely, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythensis, was assessed using real-time polymerized chain reaction (RT-PCR). Peri-implant parameters and intraoral radiographs were recorded up to 1 year after abutment connection. RESULTS In the main population, and in the periodontally compromised subgroup, the total number of periodontal pathogens around test implant sites was lower than control implant sites and adjacent tooth sites, with a statistically significant difference (P < .05). In periodontally healthy patients, the mean probing pocket depth for the test implant was 1.31 ± 0.51 mm, compared with 2.66 ± 0.83 mm for the control implant, while in periodontally compromised patients, it was 1.61 ± 0.58 mm for the test implant, compared with a mean value of 2.84 ± 1.0 mm for the control implant. CONCLUSION Implants with a laser-microtextured collar surface are not more vulnerable to pathogenic microflora colonization than implants with a machined collar surface. In both of the subgroups of patients (periodontally healthy and periodontally compromised), implants with a laser-microtextured collar surface have a better clinical outcome at 1 year of loading, compared with implants with a machined collar surface.

Clinical, Radiographic, and Histologic Evaluation of Maxillary Sinus Lift Procedure Using a Highly Purified Xenogenic Graft (Laddec(®)).

ABSTRACT Objectives The aim of this study was to evaluate the clinical, radiographic and histologic results when a highly purified xenogenic bone (Laddec®) was used as grafting material in maxillary sinuses. Material and Methods In fifteen patients requiring unilateral maxillary sinus augmentation, the grafting procedure was performed with Laddec®. Forty-two implants were installed after a 6 month healing period. The height of the augmented sinus was measured radiographically immediately after augmentation and postoperatively up to 36 months. At the time of implant placement, a bone core was harvested in each patient for histological examination. Results The cumulative implant survival rate was 97.6%. The original height was 3.65 (SD 0.7) mm and the augmented sinus height was 13.8 (SD 1.4) mm after the surgery. The reduced height of grafted xenogenic material (RDL) at the implant insertion was 0.83 (SD 0.38) mm, and at the final postoperative visit was 0.91 (SD 0.25) mm, showing no significant correlation with the follow-up periods by Spearman’s test (P = 0.118). In addition, no significant difference in the RDL was observed according to the site of implantation (P = 0.682). The mean implant marginal bone loss was 0.38 (SD 0.24) mm. Histological analysis showed the bone cores were composed of 64.72 (SD 3.44)% newly formed bone, 17.41 (SD 2.02)% connective tissue, 16.93 (SD 2.83)% residual graft particles, and 0.94 (SD 0.11)% inflammatory cells. Conclusions According to our data, the highly purified xenogenic bone (Laddec®), used as graft material in the sinus lift procedure, may create adequate bone volume, and appropriate osseointegration of dental implants.

Factors Influencing the Soft Tissue Changes Around Single Laser Microtextured Implants-Abutments in the Anterior Maxilla: A 5-Year Retrospective Study.

Purpose:The aim of this study was to evaluate the possible factors that influenced the periimplant soft tissue changes around single implants-abutments with laser-microtextured surface (LMS) in the esthetic zone. Materials and Methods:Thirty-nine units, formed by implant-abutment with LMS were studied. Variables possibly associated with the periimplant soft tissue changes were obtained from clinical measurements (plaque [present/absent], periimplant biotype [thin/thick], and probing depth); intrasurgical measurements (vertical height in millimeters of the keratinized gingiva in the vestibular part of the implant site vestibular keratinized gingiva [VKG], implant vestibular crestal exposition, vestibular crestal level, and vestibular bone width); cast models (implant position [buccal/palatal], implant abutments angle); periapical radiographs (distance from the contact point to the interproximal bone crest of the adjacent tooth [CP-BC], distance from the contact point to the implant platform [CP-P], distance from the contact point to the first bone to implant contact [CP-IB]); and digital clinical photographs. Fisher exact test was used to determine the influence of each factor on the papilla level and on the facial marginal mucosal level. Results:The papillae level at the implant sites was significantly associated with the distance from the contact point to the alveolar bone crest, whereas no association was found with other variables. Periimplant biotype, differences in the VKG, CP-BC, and CP-IB were found associated with the different facial marginal mucosal level groups. Conclusions:This study showed that the papilla level at single-tooth implants-abutments with LMS in the anterior maxilla was mainly influenced by the interproximal bone crest level of the adjacent tooth, whereas the marginal mucosal level was affected by periimplant biotype, facial bone crest level, and crestal implant exposition.

Short vs. Standard Laser-Microgrooved Implants Supporting Single and Splinted Crowns: A Prospective Study with 3 Years Follow-Up: Effectiveness of Short Implants

PURPOSE The aim of this study was to compare survival rates, marginal bone loss (MBL), and peri-implant soft tissue parameters between short and standard laser-microgrooved implants supporting single or splinted crowns 3 years after loading. MATERIALS AND METHODS 30 subjects received 1 short ( ≤ 7 mm ) and 1 standard length ( ≥ 9 mm ) laser-microgrooved implant in adjacent sites of the premolar and molar regions of the mandible or maxilla. Peri-implant soft tissue parameters and intraoral radiographs were recorded at the delivery of definitive crowns (baseline) and 3 years later. Cumulative survival rate (CSR) and marginal bone loss (MBL) in relation to crown/implant (C/I) ratio, implant length, location, type of antagonist, and type of prosthetic design (single or splinted), were evaluated. RESULTS CSR of short implants was 98%, compared to 100% for standard implants, without significant statistical difference. MBL was not significantly different over the observation period, with an average of 0.23 ± 0.6 mm and 0.27 ± 0.3 mm for short and standard implants, respectively. No statistical differences were found between short and standard implants regarding plaque (14.7% vs. 15.7%), number of sites BOP (8.3% vs. 5.9%), probing depth (1.13 ± 0.6 mm vs. 1.04 ± 0.8 mm), and mean mucosal recession (0.18 ± 0.3 mm vs. 0.22 ± 0.3 mm). Analyzing MBL in relation to the C/I ratio, implant length, location, type of antagonist, and type of prosthetic design, no statistically significant differences were found. CONCLUSION Regardless of C/I ratio, implant length, location, type of antagonist, and type of prosthetic design, short and standard laser-microgrooved implants had similar survival rates, MBL, and peri-implant soft tissue conditions over the observation period of 3 years.

Histologic and Histomorphometric Analysis of Bone Regeneration with Bovine Grafting Material after 24 Months of Healing. A Case Report

Anorganic bovine bone mineral matrix (ABBMM) has been reported to have osteoconductive properties and no inflammatory or adverse responses when used as grafting material in sinus augmentation procedures. However, controversy remains in regard to degradation rate of ABBMM. The aim of this study was to histologically and histomorphometrically evaluate the degradation of ABBMM in human bone samples obtained in one patient 24 months after sinus augmentation. Materials and Methods: The histologic and histomorphometric analysis was performed by means of light microscopy in three specimens harvested from the same patient, Results: After 24 months the tissue pattern appeared to be composed of residual particles, some in close contact with the newly formed bone, others separated by translucent areas and osteoid tissues. Newly-formed bone presented different levels of maturation and numerous osteocytes, with greater numbers in bone closer to the grafted particles (27.3% vs. 11.2%, p < 0.05). The histomorphometric analysis showed mean values of 40.84% newly-formed bone, 33.58% residual graft material, 23.84% marrow spaces, and 1.69% osteoid tissue, Conclusions: Even though ABBMM underwent considerable resorption, a great amount of residual grafting material was still present after two years of healing following sinus augmentation. This study confirms that the bovine grafts can be classified as long-term degradation materials.