ObjectivesConventional guided bone regeneration (GBR) limits the amount of bone graft due to limited soft tissue expansion. We hypothesize that the use of tissue expander will successfully augment soft tissue prior to bone graft, allowing for sufficient amount of grafting which will lead to a more stable and effective vertical bone graft. The authors aimed to evaluate effectiveness of the novel self‐inflating tissue expander for vertical augmentation in terms of soft tissue expansion, clinical outcomes, and related complications.Material and methodsA prospective, multicenter, randomized controlled trial was performed on patients requiring vertical augmentation. For experimental group patients, the tissue expander was subperiosteally implanted and followed by a tunneling bone graft without full flap reflection. Control patients underwent conventional vertical GBR. Primary objectives were to evaluate the dimensional changes of soft tissue and radiographic vertical bone gain and retention. As a secondary outcome, clinical complications and thickness changes of expanded overlying tissue were assessed and analyzed.ResultsTwenty‐three patients in each group were included. During a 4‐week expansion, two of the experimental group showed over‐expansion and one showed mucosal perforation associated with previous severe scars. The other patients showed uneventful expansion and mean tissue augmentation was 6.88 ± 1.64 mm vertically. Ultrasonographic measurements of overlying gingiva revealed no thinning after tissue expansion (p > .05). Significantly higher vertical bone gain was shown in the experimental group (5.12 ± 1.25 mm) compared with that in the control patients (4.22 ± 1.15 mm; p < .05). After a 6‐month retention period, the mean vertical bone measurement of the controls had decreased to 1.90 mm (55.0% reduction), which was a significantly greater decrease than that in the experimental group (mean 3.55 mm, 30.7% reduction; p < .05).ConclusionOur results demonstrated the effectiveness of tissue expanders followed by tunneling bone graft for vertical augmentation; however, studies comparing the two techniques without tissue expanders are needed to elucidate the net effect of tissue expansion.
Background: Regional acceleratory phenomenon (RAP) is demonstrated to decrease regional bone mineral density and accelerate bone turnover. Hypothesizing that RAP can negatively affect the osseointegration of biomaterials, this study aimed to investigate the possible influence of the RAP on dental implant osseointegration.Materials and Methods: Orthognathic surgery, one of the major surgeries on oral and maxillofacial region was set as intervention for RAP. Considering that RAP exerts its physiologic effects until 4 months after noxious stimuli, patients were classified according to the time interval between orthognathic surgery and dental implant installation; group I was designated to patients who had implant installation within 4 months from orthognathic surgery. Group II were those with installation after 4-12 months and group III was longer than 12 months. Radiographic and clinical evaluations of dental implants including peri-implant marginal bone changes (MBR), implant stability, cumulative survival rates were analyzed.Results: A total of 54 patients with 106 implants (mean follow-up of 72.6 months) were included in the study. MBR was significantly higher in group I (2.62 ± 0.91 mm) and II (2.25 ± 0.95 mm) compared to that of group III (0.94 ± 0.90 mm) at last follow up (P < 0.05) and this group difference over time was also significant (P < 0.001). Compared to group III, groups I and II exhibited lower ISQ values and higher biological complications including periimplantitis and peri-implant gingivitis (P < 0.05). Group I showed significantly low-cumulative survival rate (89.2%; implant-level) compared to groups II and III.Conclusions: In this study, impaired osseointegration of dental implants was demonstrated associated with orthognathic surgery. Micro-environmental changes of hard tissue induced by major surgery on the jaw showed deteriorating effects on integrity of biomaterial osseointegration.Special considerations should be addressed for ideal treatment results and prognosis.dental implants, orthognathic surgery, Osseointegration, osteoporosis, regional acceleratory phenomenon biomaterial. 2 In this regard, numerous studies demonstrated that abnormal bone condition such as osteoporosis and high bone metabolic turnover rates would not be favorable to biological fixation, primary stability, and final osseointegration. 3,4Regional acceleratory phenomenon (RAP), which was defined as a complex reaction of mammalian tissues to diverse noxious stimuli involving acceleration and domination of most ongoing normal vital tissue processes, 5 has widely been applied to the field of dentistry, especially in orthodontics, such as periodontally accelerated osteogenic orthodontics 6 and surgery-first orthodontics for rapid teeth movement. 7 It has been known to be induced by various noxious stimuli such as trauma, osteotomy, corticotomy as well as periodontal flap surgery, alveolar graft, and implant surgery. 8 Although a large part of pathophysiological mechanisms of RAP is still unclear, it has mainly been proposed...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.