ABSTRACT
BACKGROUND: Rehabilitation in the anterior region requires specific conditions for success, such as the presence of papilla, emergence profile, and balance between pink and white esthetic. OBJECTIVES: This systematic review aimed to evaluate the esthetic risk associated with immediate implant placement with immediate restoration in the anterior superior area, where the facial bone plate may be absent or deficient. MATERIAL AND METHODS: The search was done in PubMed, Embase, Cochrane, Lilacs, Scopus, Scielo, and Google Scholar databases. The investigation involved clinical studies and observational studies published between January 2012 and July 2023. Studies were excluded if there was less than 12-month follow-up, no immediate restoration or facial defect, heavy smokers, or systemic disease. The risk of bias was assessed using the ROBINS-I and Modified-Cochrane RoB tools. RESULTS: Twelve studies were included in this systematic review. The thinner the facial plate, the higher the alveolus's risk of gingival recession or shrinkage. There was an increased interproximal recession when the thin phenotype was associated with flap surgery. An increase in pink esthetic score (PES) was reached when immediate implant placement (IIP) and immediate restoration were done. Soft tissue augmentation achieved more gingival-level stability. Regardless of the initial phenotype, an esthetic outcome was delivered. The risk of bias was high in 1 study and moderate in 3 studies. CONCLUSION: It is possible to conclude that esthetic results and increased final PES or patient satisfaction index in IIP treatments associated with immediate restoration could be obtained even in buccal bone wall defects or gingival recession, regardless of their extension.
ABSTRACT
OBJECTIVES: This study aimed to evaluate the bone formation process in experimental defects created on rabbit calvarial, in which one of the bone defects was covered by the impermeable membrane before suturing the skin flap, while the other was closed only by the cutaneous flap. The experimental holes were filled only by the blood clot. MATERIAL AND METHODS: Sixteen New Zealand female rabbits weighing between 3.5 and 4 kg were used. Two experimental bone defects were made in the rabbit calvarial. The holes were filled only with the blood clot and one of them was covered with an impermeable polypropylene membrane. A histological analysis was made at 21 and 42 days following the surgery. Histological evaluation consisted of the following: 1. inflammatory process; 2. Bone repair; 3. Bone remodeling; 4. Presence of osteoid matrix and mineralization, and 5. Formation of hematopoietic tissue. Each characteristic was analyzed semi quantitatively. RESULTS: There was a statistical difference between the test and the control group at 21 days of healing in the following items: presence of cementation line (p = 0.012), presence of osteoid tissue (p = 0.012), and trabecular bone tissue development and mineralization (p = 0.012). A greater amount of lamellar bone tissue (mature) was also observed in the test group compared to the control group. CONCLUSION: The semiquantitative analysis showed that at 21 days there was a superiority of the repair process in the test group; at 42 days there was no significant difference in bone formation between the two groups; and that the polypropylene membrane is feasible to be used in GBR. CLINICAL SIGNIFICANCE: The impermeable polypropylene barrier is feasible for use in the guided bone regeneration technique. It can be used only on the blood clot, without the need for grafting, and can be easily removed a few days after surgery. These results are unprecedented.
