Several techniques have been proposed for bone regeneration in patients with atrophic ridges. Nowadays, GBR represents the gold standard, and it allows obtaining sufficient bone volumes for a correct implant-prosthetic rehabilitation. Our goal is to perform a systematic review of the literature on the use of titanium meshes in GBR in order to evaluate the reliability of the procedure, the regeneration obtained, and the failures. Furthermore, we will evaluate the success and survival rate of the inserted implants. The selected articles concern vertical and/or horizontal regeneration of the alveolar ridge using titanium grids, in association or not with biomaterials, before and simultaneously with implant placement. Six articles were selected for the present review, including a total of 139 patients, 156 sites, and 303 implants. Titanium grids in combination with autogenous bone were used in 2 cases, 5 in combination with a mixture of autogenous bone and bone substitutes. The overall survival and success rates of implants were 98.3% and 85.25%, respectively. In conclusion, our review shows how the use of titanium mesh represented a predictable method for the rehabilitation of complex atrophic sites.

Background: The alveolar ridge undergoes reabsorption and atrophy subsequent to tooth removal and thus exhibits a wide range of dimensional changes. Preservation of the alveolar crest after tooth extraction is essential to enhance the surgical site before implant fixture placement. The aim of this randomized clinical study is to investigate and compare the need for additional augmentation procedures at implant insertion, as well as the success rate and marginal bone loss for implants placed in the grafted sites versus those placed in naturally healed sites.Methods: Forty patients with ≥1 hopeless tooth were randomly allocated to: 1) a test group, receiving extraction and grafting corticocancellous porcine bone; and 2) a control group, receiving extraction without any graft. After 7 months of healing, implants were inserted in each of the sites. The implants were submerged and loaded after 4 months with metal–ceramic rehabilitation. The follow‐up included evaluation of implant diameter and length, the need for additional augmentation procedures at implant placement, implant failure, and marginal bone level changes. All patients were followed over a 3‐year period.Results: One implant failed in the control group at the second stage of surgery (6 months after placement); one implant failed in the test group after 2 years of loading. The cumulative implant success rate at the 3‐year follow‐up visit reached 95% for both groups. No statistically significant differences were detected for marginal bone changes between the two groups.Conclusions: It was concluded that implants placed into grafted extraction sockets exhibited a clinical performance similar to implants placed into non‐grafted sites in terms of implant survival and marginal bone loss. However, grafted sites allowed placement of larger implants and required less augmentation procedures at implant placement when compared to naturally healed sites.

To examine the distribution of bacteria into the internal and external surfaces of failed implants using histologic analysis. There were 10 failed pure titanium and 5 failed hydroxyapatite-coated titanium implants consecutively removed various years after their placement. Criteria for fixture removal were peri-implant radiolucency and clinical mobility. The mobile fixtures were retrieved with the patients under local anesthesia. Fixtures were removed maintaining the abutments with the aim to observe the bacterial infiltration at the level of abutment/implant interface and on the implant surface. A thin radiolucent space was always present around all the failed implants. The abutments screws were tightly secured in all clinical cases. The bacterial cells were composed of cocci and filaments, which were adherent to the implant surface with an orientation perpendicular to the long axis of the implant. All the specimens included in this study showed bacteria at the level of implant/abutment interface. Histologic analysis at the level of abutment/implant interface in 2-stage implants identified heavy bacterial colonization. These findings appear to support those studies showing bacteria penetration at the level of the micro-gap, which can legitimate the hypothesis that the micro-gap at the bone level could present a risk for bone loss caused by bacterial colonization.

Background: Genes involved in different biologic processes form complex interaction networks. However, only a few have a high number of interactions with the other genes in the network. In previous bioinformatics and experimental studies concerning the T lymphocyte cell cycle, these genes were identified and termed “leader genes.” In this work, genes involved in human periodontitis were tentatively identified and ranked according to their number of interactions to obtain a preliminary, broader view of molecular mechanisms of periodontitis and plan targeted experimentation.Methods: Genes were identified with interrelated queries of several databases. The interactions among these genes were mapped and given a significance score. The weighted number of links (weighted sum of scores for every interaction in which the given gene is involved) was calculated for each gene. Genes were clustered according to this parameter. The genes in the highest cluster were termed leader genes.Results: Sixty‐one genes involved or potentially involved in periodontitis were identified. Only five were identified as leader genes, whereas 12 others were ranked in an immediately lower cluster. For 10 of 17 genes there is evidence of involvement in periodontitis; seven new genes that are potentially involved in this disease were identified. The involvement in periodontitis has been completely established for only two leader genes.Conclusions: We applied a validated bioinformatics algorithm to increase our knowledge of molecular mechanisms of periodontitis. Even with the limitations of this ab initio analysis, this theoretical study can suggest ad hoc experimentation targeted on significant genes and, therefore, simpler than mass‐scale molecular genomics. Moreover, the identification of leader genes might suggest new potential risk factors and therapeutic targets.