Peri-implant keratinized mucosa (PIKM) augmentation refers to surgical procedures aimed at increasing the width of PIKM. Consensus reports emphasize the necessity of maintaining a minimum width of PIKM to ensure long-term peri-implant health. Currently, several surgical techniques have been validated for their effectiveness in increasing PIKM. However, the selection and application of PIKM augmentation methods may present challenges for dental practitioners due to heterogeneity in surgical techniques, variations in clinical scenarios, and anatomical differences. Therefore, clear guidelines and considerations for PIKM augmentation are needed. This expert consensus focuses on the commonly employed surgical techniques for PIKM augmentation and the factors influencing their selection at second-stage surgery. It aims to establish a standardized framework for assessing, planning, and executing PIKM augmentation procedures, with the goal of offering evidence-based guidance to enhance the predictability and success of PIKM augmentation.
Humans ; Consensus ; Dental Implants ; Mouth Mucosa/surgery* ; Keratins

Guided bone regeneration technology applied in alveolar bone defect regeneration is based on the barrier function and space maintenance of the barrier membrane. Therefore, traditional development strategies for barrier membranes focus on their physical barrier function, degradation characteristics and biocompatibility to avoid immunogenicity. However, not only does the barrier membrane passively block connective tissue, it is recognized as a “foreign body”that triggers a persistent host immune response, known as a foreign body reaction. The theories of osteoimmunology reveal a close relationship between the immune system and bone system and emphasize the role of immune cells in bone tissue-related pathophysiological processes. Based on these findings, we propose a novel development strategy for barrier membranes based on immune microenvironment regulation: by manipulating mechanical properties, surface properties and physiochemical properties, barrier membranes are endowed with an improved immunomodulation ability, which helps to regulate immune cell reactions to induce a favorable local immune microenvironment, thus coordinating osteogenesis and osteoclastogenesis as well as barrier membrane degradation to increase the efficiency of barrier membranes in GBR applications. In this paper, we review the development of barrier membranes and their close relationship to the immune microenvironment concerning bone regeneration and membrane degradation. Additionally, the outcomes of research on barrier membranes based on the regulation of the immune microenvironment have been summarized to improve the osteogenesis efficiency of barrier membranes and solve the problem of the regeneration and repair of bone defects, especially alveolar bone defects.

Objective:To evaluate the effects of fluorinated porcine hydroxyapatite (FPHA) on guided bone regeneration of peri-implant buccal bone defects in canine mandible.Methods:Six male beagle dogs were randomly divided into two groups with different time points (4 weeks and 12 weeks after implants placement), with 3 dogs in each group. Bilateral mandibular second premolars, first molars, and second molars in each dog were extracted. The wounds were allowed to heal for 12 weeks. For each dog, four implant beds were prepared in each side and standardized peri-implant buccal bone defect was created at each implant site. After implants placement, the defect sites were randomly allocated in a split-mouth design to blank control group, deproteinized bovine bone mineral (DBBM), the porcine hydroxyapatite (PHA), FPHA and covered with collagen membranes. The animals were sacrificed 4 or 12 weeks after the surgery. Biopsies of the implant sites were obtained for micro-CT evaluation [bone volume fraction (BV/TV) and bone trabecular separation degree (Tb.Sp)] and histological analysis.Results:Micro-CT results showed that 4 weeks after implants placement, PHA, FPHA and DBBM successfully maintained the contour of alveolar ridge at the buccal aspect of the implants, while the contour of alveolar ridge collapsed in the blank control group. BV/TV in the FPHA group [(24.77±2.20) %] was significantly higher than that in the PHA group [(16.89±1.70)%] and DBBM group [(15.68±3.15)%] ( P<0.05). Tb.Sp in the FPHA group (0.70±0.07) was significantly lower than that in the DBBM group (1.03±0.19) ( P<0.05). Twelve weeks after implants placement, the alveolar ridge contour of the grafted sites in PHA, FPHA and DBBM group remained stable. The alveolar ridge of the blank control group was still collapsed. There was no significant difference in BV/TV and Tb.Sp between PHA group, FPHA group and DBBM group. The histomorphological analysis showed that 4 weeks after implants placement, in the central area of the defect, the amount and maturity of new bone (NB) around the material particles in FPHA group was higher than that in PHA group and DBBM group. Osseointegration could be observed between the NB and implant surface in all the four groups. Twelve weeks after implants placement, the material particles were surrounded by a large number of mature NB in PHA, FPHA and DBBM group. Conclusions:The incorporation of fluoride ion into PHA could effectively promote the repair of peri-implant bone defects in the early stage of guided bone regeneration.