Efficacy of stem cells in bone rehabilitation in patients with alveolar bone atrophy: a systematic review.

BACKGROUND: Biomedical engineering proposes the use of stem cells as a bone rehabilitation treatment in patients with alveolar bone defects. Many authors suggest that this innovative technique could represent the future of bone regeneration in dentistry. The present study systematically reviewed the efficacy of stem cells in bone regeneration in patients with alveolar bone atrophy. MATERIAL AND METHODS: The study was developed following the criteria of the PRISMA guideline (2020). The literature review was conducted in Pubmed, Medline Complete, and Scopus. The search algorithms used the following key words: stem cells, bone regeneration, and alveolar ridge augmentation. To assess the risk of bias, the CASPe methodology was used. RESULTS: Seven clinical trials in humans were included in this systematic review. In all the studies, the proposed objective of bone regeneration by using stem cells was achieved, although in a different way with different results. Although the authors of the analysed clinical trials achieved favourable results, they highlighted the presence of multiple limitations throughout bone regeneration treatments, such as scarce scientific literature on stem cells, a reduced number of follow-up studies, and a lack of a standardized international protocol. CONCLUSIONS: Based on the analysed studies, it is concluded that the therapy proposed by tissue engineering through the use of stem cells to rehabilitate patients with bone atrophies can be considered effective. In addition, the need for further studies and standardization of protocols is highlighted.

The use of short dental implants in clinical practice: literature review.

When anatomic structures and ridge resorption limit the placement of a standard implant, the clinician can apply augmentation techniques or use short implants. A literature review was carried out to evaluate the differences in survival rate and the rational use of short implants. Electronic search (MEDLINE) and manual search have been performed to select papers from 2000 to 2008. Of all the inclusion criteria the most relevant were: 1) studies with data on short implants; 2) studies on humans; 3) prospective, longitudinal, retrospective and multicenter studies; 4) no restrictions were applied about study design; 5) no implant type selection was applied. Exclusion criteria were: 1) studies concerning treatment of patients with conditions possibly affecting survival or success rates of implant treatment; 2) studies concerning treatment of patients with non-treated periodontal disease; 3) implants placed in non-healed ridge, such as postextractive short implants. A total of 13 studies fulfilled the inclusion criteria. Most of the studies have reported different survival rate for short and standard implants. The difference is not significant. The recent literature have demonstrated a similar survival rate for short and standard implants. Older articles have demonstrated a lower survival rate for short implants. The treatment planning is a key factor for success in the use of short implants. Some of the parameters the clinician should consider are: 1) area to rehabilitate as well as bone quality; 2) length of the implant; 3) implant diameter; 4) type of implant and surface treatment; 5) crown to implant ratio of the final prostheses; 6) type of prostheses; 7) connection to other implants; 8) occlusal/ parafunctional load; 9) prosthetic complications. Although in the literature there are no studies that analyze short implant survival from the point of view of each key factors, it can be assumed that a careful treatment planning can lead the clinician to obtain a successful rehabilitation.