Is Oral Lichen Planus A Risk Factor For Peri-implant Diseases?

BackgroundRecently,Oral lichen planus(OLP)has been questioned to be a potential risk indicator for peri-implant diseases(PIDs).Some studies did not observe any difference in the success rate between OLP patients and normal controls.Moreover,the quality of life of the OLP group was improved compared with the non-implanted group after implant repair treatment,there were also studies showing that the position of the implant in the jaw did not affect the recovery of OLP lesions.These evidences made some scholars not object to implant treatment for patients with OLP.However,OLP patients have been found to have poor oral hygiene.Furthermore,some studies have shown a very high implant failure rate for OLP patients receiving implant placement during the acute stages.PIM with desquamative gingivitis(DG)in the OLP group occurred more frequently than non-desquamative gingivitis in the OLP group in this subgroup of implant patients in the prospective study.These concerns have previously made some dentists consider OLP a contraindication to implant treatment.Notably,most of the studies regarding implantation in OLP populations were observational studies with small sample sizes.Hence,whether dental implantation in OLP patients is safe remains inconclusive.ObjectivesTo evaluate whether OLP is a risk factor for PIDs with a systematic review and metaanalysis.In order to provide a certain reference basis for the evaluation of implant risk and the possibility of implant treatment of OLP patients.Material and Methods 1.Search strategyFive electronic databases including Medline,Embase,Web of Science,the Cochrane Library and Scopus were searched.Manual searching in dental journals,especially those focusing on implantology,was also performed.2.Inclusion and exclusion criteria:1)Inclusion criteria: observational human studies,such as case-control,crosssectional,retrospective or prospective cohort studies;studies in which OLP and PIDs were the main exposure factor and outcome,respectively;both OLP and PIDs should be definitely diagnosed in studies,studies with a follow-up time of ≥1 month after implant placement.2)Exclusion criteria: studies lacking control groups(i.e.,a non-OLP group);narrative reviews,comments,letters,case reports or series,and conference abstracts;and duplicates were removed,and the latest or most complete literature was retained.3.Data extraction and managementThe following research information was extracted: type of research;sample framework;sample size,sex and age of participants;diagnostic criteria for PI,PIM and OLP;follow-up time;confounding factors relative to exposure factors;primary outcomes and related outcome indicators.4.Quality assessmentThe quality of the included literature regarding risk of bias and methodology was assessed with Newcastle-Ottawa Scale or the Agency for Healthcare Research and Quality.5.Data synthesisStatistical heterogeneity in risk in patients suffering from PIDs in the collected studies was evaluated using both risk ratios(RRs)and I2 measures.When suitable,meta-analysis was used to assess risk in patients suffering from PIDs based on implant and patient characteristics.A random effects approach was used if there was mild to moderate statistical heterogeneity,otherwise,a fixed-effect approach was chosen.Considering that only observational studies were included in the present systematic review,the primary outcome variable was the RRs of PI and PIM.The RRs were calculated with 95% confidence intervals(CIs)(Review Manager,v5.2,The Nordic Cochrane Center,The Cochrane Collaboration,Copenhagen,Denmark)to quantify the association between OLP and the risk of PI and PIM.Forest plots were generated showing the RRs and 95% CIs of the involved studies.If there were more than 10 studies included in the meta-analysis,publication bias was evaluated qualitatively by a funnel plot.ResultsA total of 66 studies were identified after electronic and manual searches.According to the inclusion criteria,duplicate and review articles,case reports,and articles without control groups were excluded,the remaining 2 articles were retained for final review,included one prospective study and one cross-sectional study.Two studies were enrolled and evaluated as high quality,which totally contained 68 participants receiving 222(OLP vs.non-OLP,112 vs.110)implants with 12 to 120-month follow-up time.Proportions of implants with PIDs between OLP and non-OLP groups were as follows: 19.6%(22/112)vs.22.7%(25/110)for PIM;17.0%(19/112)vs.10.9%(12/110)for PI.Meta-analysis found no recognizable difference in number of implants with PIDs(PI: RR = 1.49,95% CI 0.77-2.90,P = 0.24;PIM:RR = 0.88,95% CI 0.53-1.46,P = 0.61;PIDs: RR = 1.08,95% CI 0.75-1.55,P = 0.68)or BOP(RR = 0.90,95% CI: 0.70-1.15,P = 0.40)between OLP and non-OLP groups.Due to the different data reporting formats,the periodontal probing depth(PPD)and marginal bone loss(MBL)could not be integrated and analyzed.ConclusionsAccording to the existing evidence,there is no difference in the risk of PIDs between OLP and non-OLP participants at the implant level.Available literature regarding the effects of OLP on PIDs remains very limited.Large-scale prospective trials are required to test the findings.OLP should not be considered as a contraindication for implant treatment in patients who do not have evident symptoms or mucosal erosive congestion and have good oral hygiene.