==== Front Med Oral Patol Oral Cir Bucal Med Oral Patol Oral Cir Bucal Medicina Oral S.L. Medicina Oral, Patología Oral y Cirugía Bucal 1698-4447 1698-6946 Medicina Oral S.L. 37330966 25792 10.4317/medoral.25792 Research Implantology Effect of the buccal fat pad in the prevention of zygomatic implant surgery postoperative complications: A pilot study Blanco-Ruiz Sonia 1 Molinero-Mourelle Pedro 23 Blanco-Ruiz Miriam 4 Fernández-Tresguerres Francisco González 1 Blanco-Samper Senén 1 López-Quiles Juan 1 1 Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, Madrid, Spain 2 Department of Conservative Dentistry and Orofacial Prosthodontics, Complutense University of Madrid, Madrid, Spain 3 Department of Reconstructive Dentistry and Gerodontology, University of Bern, Bern, Switzerland 4 Department of Otorhinolaryngology, Head and Neck Surgery, University General Hospital, Ciudad Real, Spain Department of Department of Dental Clinical Specialties Faculty of Dentistry, Complutense University of Madrid Plaza Ramón y Cajal s/n, 28040, Madrid, Spain , E-mail: sonblanc@ucm.es 7 2023 18 6 2023 28 4 e371e377 8 5 2023 24 10 2022 Copyright: © 2023 Medicina Oral S.L. 2023 https://creativecommons.org/licenses/by/2.5/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background Zygomatic implants have been used to treat severe atrophy maxilla. Since its description, the technique has been improved in order to reduce patient morbidity as well as prosthesis rehabilitation time. Despite the improvements in the procedure, zygomatic implant treatments still have complications related to the peri-implant soft-tissue; a probing depth greater than 6 millimeter (mm) and a prevalence of bleeding on probing of 45% have been described. The mobilization of the buccal fat has been used to manage different oral and maxillofacial soft-tissue pathologies. The aim of this study was to assess whether the buccal fat pad might prevent mucosal dehiscence and avoid potential postoperative complications when is placed covering the body part of the zygomatic implants. Material and Methods In this pilot study, 7 patients were enrolled and a total of 28 zygomatic implants were placed and evaluated during a 12-month follow-up period. Surgical sites were randomly divided into two groups before implant placement: control group (A; in which no buccal fat pad was applied) and experimental group (B). Peri-implant soft tissue thickness difference, pain using a Visual Analog Scale (VAS), swelling, hematoma, buccal soft tissue healing and sinusitis, were evaluated. The implant survival rate was determined according the Aparicio success criteria and compared between the control and experimental procedure. Results A nonstatistical difference was found between groups regarding to pain. The experimental group showed higher soft-tissues thickness (p= 0.03) and the implant survival rate was 100% in both groups. Conclusions The mobilization of the buccal fat pad to cover the body of the zygomatic implants increases peri-implant soft-tissue thickness, without increasing the postoperative pain. Key words:Zygomatic implants, maxillary atrophy, Complications, Postoperative care, Swelling, Pain. ==== Body pmcIntroduction Complex oral surgeries with the use of bone regeneration materials have been used to treat bone reabsorption processes (1). However, the management of severe maxillary atrophy in long-term edentulous patients is still a challenge in dentistry. Since the first description of zygomatic implants and the surgery procedure in 1990 (2), the technique has been modified and improved (2-6) to reduce patient morbidity as well as treatment cost and time (7,8). Some authors have pointed out that survival rates of zygomatic implants are similar to conventional implants rates, being above 99.5% (8,9). Nevertheless, zygomatic implants are not devoid of complications, (5,7-14) the most frequent being peri-implant soft-tissue disruptions, with a mean probing depth greater than 6 millimeter (mm) and a prevalence of bleeding on probing of 45%. Although soft-tissue variations have been related to the presence of pathogenic bacteria, probing depth was found to be increased in these implants even in the absence of microorganisms (14). In connection with this, peri-implant inflammation followed by soft-tissue recessions in extrasinusal zygomatic implants could potentially derive from the exposed part of the implant because the zygomatic implant body is in intimate contact with oral mucosal tissue (5). The buccal fat pad has been used to manage diverse sort of oral and maxillofacial complications (15,16). Some authors have employed the buccal fat pad during zygomatic implant surgeries and have suggested the absence of post-surgery and implant complications during a follow-up period of more than 15 months (12). The aim of the study was to assess if the repositioning of the buccal fat pad might prevent the gingival recession. Hence, this study aimed to test hypothesis that covering the exposed part of the zygomatic implant with the buccal fat pad would prevent future recession of peri-implant soft-tissues because the fatty-tissue might increase oral mucosal thickness. Material and Methods - Study design A pilot, prospective, single-blind, split-mouth and randomized clinical trial was conducted in patients who required treatment with two implants in each zygomatic bone. Participants were followed up at 72 hours, 7 days, 15 days, 3-, 6- and 12-months post-surgery; The present trial was conducted in accordance with Helsinki Declaration (2013) and the Ethical committee approvement from Clínico San Carlos Hospital (19/531-R_P). - Participants Participants were recruited through the research project carried out by the Oral Surgery postgraduate clinic at Universidad Complutense Madrid. All patients enrolled were over 18 years-old, with an ASA I or ASA II surgical risk according to the American Society of Anesthesiologists (ASA). Moreover, patients who had less than 4 mm of residual maxillary bone measured with cone-beam computer tomography needed treatment with two zygomatic implants in each malar bone. All participants were informed in detail about the nature of the study and gave their written informed consent before being included. - Surgical procedure Patients were treated under intravenous conscious sedation with benzodiazepine (Midazolam 1 mg/ml, Anesfarma, Spain) combined with local anesthesia of articaine hydrochloride with epinephrine 0,1 mg/ milliliter(ml) (Ultracain 40 mg, Normon, Spain). The surgical procedure was performed by a highly-experienced maxillofacial surgeon with over 30 years of clinical experience (J.L-Q.). All zygomatic implants were placed in the patient in only one surgical session. Moreover, each participant was part of two study groups: the control group (A) in which after two zygomatic implants, the covering flap was sutured and the experimental group (B) in which, after implant placement, the buccal fat pad was repositioned covering the out-bone implant body, (Fig. 1) followed by the flap suture. Figure 1 Surgical procedure. In the study side the buccal fat pad is covering body implants. All previous surgery steps were the same for both groups and the surgeon placed HE Zygomatic Implant Neodent® (Straumann AG; Basel, Switzerland) following its drill sequence system. After all zygomatic implants were placed, the implants were classified in accordance with ZAGA classification system (6). Postoperative drug treatment included omeprazole 20 mg (Kern Pharma; Madrid, Spain) once-daily for 20 days, Augmentin 875/125 mg (GSK, GlaxoSmithKline; Brentford, U.K) 1 dose every 8 hours for 15 days, Deflazacort 30m (Laboratorios Menarini S.A; Napoles, Italy) 2 doses/24 hours for 5 days, Dexketoprofen 25 mg (Laboratorios Menarini S.A; Napoles, Italy) 1 dose/8 hours for 5 days, Metamizole 575 mg (Laboratorio Stada S.L; Barcelona, Spain) 1 dose/8 hours for 3 days. Treatment also included: oxymetazoline 0.5 mg/ml nasal spray, a nostril-nebulizer three times a day for 3 days, fluticasone furoate, two spray actuations daily for 15 days and nasal wash with a saline solution (GSK, GlaxoSmithKline; Brentford, U.K). - Outcome measures The primary outcome was peri-implant soft tissue thickness difference between both groups, using the average of three measurement points on the buccal side of the implant platform registered with a periodontal probe (HH12 periodontal probe, Deppeler SA). Secondary outcomes were: pain assessed using a Visual Analog Scale (VAS), swelling assessed using the Amin & Laskin method (17), hematoma measured according to the Gutiérrez y Wuesthoff method (18). Sinusitis was evaluated using the Hwang questionnaire (19) and the implant survival rate following Aparicio success criteria (20). All measured outcomes variables were assessed by an independent, trained and non-blinded researcher (S.B.R) (Fig. 2). Figure 2 Flow chart of the study protocol according to Consort guidelines, including the number of participants enrolled and the period of the outcome measures. - Sample size, randomized sequence, and statistical analysis Being a pilot study, no sample size was calculated, and seven patients were enrolled in this study. Hence, a total of 28 zygomatic implants were analyzed been it considered the statistical unit. The sample was randomized through a simple process using Matlab 28b (Math Works. Natick, Massachusetts, USA). A descriptive statistical analysis was carried out using measures of central and dispersion tendency and percentages. In addition, Shapiro-wilk test was used to assess the normal distribution of the data and a non-parametrical test (Wilcoxon) to contrast hypothesis. Results After 12 months of follow-up, 28 zygomatic implants were evaluated in seven patients (71% female and 29% male). The mean age among participants was 55.57±6.39 years-old, the average of the surgical time spent was 172.14±54.60 minutes (Table 1). Shapiro-wilk test confirmed the normal distribution of pain data in both groups; however, swelling parameter distribution did not fit the standardized criteria, so both clinical outcomes were assessed with a non-parametric test (Wilcoxon). Regarding to the swelling outcome variable, a statistical difference was found between both groups (p= 0.043). Indeed, the mean percentage of swelling in the study group was 12.16%, compared to 8.05% in the control group. Moreover, the maximum percentage of swelling registered in the experimental group was a 6.79% greater than in the control-group, with a maximum proportion of swelling of 22.42% and 15.63%, respectively. Swelling and pain outcomes are displayed in Table 2. Three patients had hematoma that happened always as a bilateral episode. However, a greater number of faces-areas were affected in the study group. Moreover, cheek section was drawn in all test hemifaces sides while only that region was just affected in one out of three control group. In a control-side, the suture dehiscence occurred at day 5 post-surgery in one participant (14,28%). On the other hand, six months after treatment, one patient in the control-group showed sinusitis and skin periorbital fistula. Peri-implant soft-tissue thickness was evaluated in 20 out of 28 implants due to two patients did not attend to the follow-up, the experimental group showed an average of 5.2±1.47 mm while in the control group it was 3±1.05 mm, (p=0.03). In the control group a 14.3 % of the implant showed 10 mm of mucosal dehiscence however no one of the implant from the study group. This showed in Table 3. Table 1 Descriptive data about demographical parameters, surgical time, implant position and type. Table 2 Comparison of two outcomes between groups (control-test): the percentage of swelling and pain (VAS) in each participant and the mean value together with the statistical deviation. Table 3 Peri-implant soft-tissue thickness analysis and description of peri-implant soft-tissue recession. Discussion Zygomatic implant surgery is considered an advanced surgical intervention and requires more surgical time than conventional implant techniques. However, the development and variations in zygomatic implant placement technique have reduced the surgical time (5) overall, buccal fat pad replacement involves more surgical trauma because an additional procedure is needed. Considering the literature, Guennal, et al. reported that patients showed an overall worse postoperative period when buccal fat pad had been mobilized (12). In the same line, the present study showed higher swelling rates and more areas affected by hematoma. However, non-significant differences in pain were found between groups. On the other hand, Esposito, et al., linked bruise occurrence with the use of rotary drill material during zygomatic implants placement (21). Therefore, the presence of bilateral hematoma might be related with the drill material instead of the mobilization of the buccal fat pad even though a greater area was affected in the experimental group. Extrasinusal zygomatic implants enhance prothesis rehabilitation, shrinking cantilevers palatal-buccal owing to implant head arise at bone crest level (5,6,10). Nevertheless, the intimated contact between extrasinus implants body with buccal soft tissue may alter them (5,12). Molinero-Mourelle, et al. and Charcanovic, et al. agree with the fact that buccal mucosal modification is the third more frequent complication (8,11). Moreover, Yates, et al., found gingival recession from between 2-4 mm in zygomatic implants after a follow-up period of 6 years (13). Conventional implants with a thin soft-tissue phenotypes, required subepithelial or free connective tissue graft to prevent the development of peri-implant mucosal dehiscence (22,23). In addition, based on current knowledge, the buccal fat pad has been successfully used to cover tooth recessions (24,25). Hence, from other perspective but following with a similar investigation line, the present study showed that peri-implant buccal mucosal dehiscence was significantly worse in those implants that were not covered with the buccal fat pad. Also, we found higher peri-implant soft tissue thickness in the study group compared to control group, the average of the peri-implant soft-tissue thickness being more than 2 mm thicker in the study side as compared to the control side. Therefore, the mobilization of the buccal fat pad might prevent peri-implant recessions. Regarding other assessed complications, such as sinusitis (8,10,11,26,27), this study agrees with other authors in that extrasinusal zygomatic implant show lower incidence of sinusitis than intrasinusal zygomatic implants (10,28). The survival rate of the zygomatic implants would be greater than 97% (28-30) and 95% (27) after a follow-up period of 10 years and 18 years, respectively. This study did not show any failure of the zygomatic implants during a follow-up period of one year. The authors of the present study acknowledge some limitations in the study design (pilot study and single blind) that could had impacted in the study results. It must be taken into consideration that the person who gathered the outcomes variables was not blinded. In addition, not all implants were classified as the same type of ZAGA; future studies should homogenize and group patients regarding the ZAGA classification. Moreover, there were more female patients, and the sample size could not be representative. Yet, even though we cannot establish accurate conclusions about the use of the buccal fat pad in the prevention of extrasinus zygomatic implants recessions due to the paucity of the sample size (external validity), this study showed promising outcomes. Therefore, more randomized clinical trials are warranted to confirm the technique effectiveness in complications in zygomatic implants. Conclusions Within the limitations of this pilot study, the use of the buccal fat pad for covering the body part of the zygomatic implant appeared to be a reliable option in the prevention of peri-implant soft tissue dehiscence, as the buccal fat pad increased the soft-tissue around zygomatic implants in the study group. However, this procedure was associated with an increased rate of postoperative swelling. Ackcnowledgements The authors would like to thank to Dr. Belen Estevez, Puerta de Hierro University Hospital for performing the intravenous conscious sedation and Dr. Mariano Zomeño Rodriguez for reviewing the English language. Authors contributions SB-R conducted the conception and study design, the interpretation of the data, the drafting of the manuscript , performed the writing original draft and approved the final manuscript.; P.M-M performed the writing-original draft, writing-review, editing the manuscript and approved the final manuscript; M.B-R. was involved in the study design, the data interpretation of the data and approved the final manuscript.; F.G.F-T. writing-review, editing the manuscript and approved the final manuscript; S.B-S conducted the conception and study design, the interpretation of the data and approved the final manuscript; J.L-Q. performed the project administration and supervision, the conception and study design, the interpretation of the data, the drafting of the manuscript and approved the final manuscript. Ethics Ethical committee approvement from Clínico San Carlos Hospital (19/531-R_P). Conflicts of interest The authors declare no conflict of interest. Funding This research did not receive any external funding. ==== Refs 1 Aghaloo TL Misch C Lin GH Iacono VJ Wang HL Bone augmentation of the edentulous maxilla for implant placement: A systematic review Int J Oral Maxillofac Implants 2016 31 s19 30 27228250 2 Branemark PI Gröndahl K Öhrnell LO Nilsson P Petruson B Svensson B Zygoma fixture in the management of advanced atrophy of the maxilla: technique and long-term results Scand J Plast Reconstr Surg Hand Surg 2004 38 70 85 15202664 3 Stella JP Warner MR Sinus slot technique for simplification and improved orientation of zygomatic dental implants: a novel technical note Int J Oral Maxillofac Implants 2000 15 889 93 11151591 4 Bothur S Jonsson G Sandahl L Modified technique using multiple zygomatic implants in the reconstruction of the atrophic maxilla: a technical note Int J Oral Maxillofac Implants 2003 18 902 4 14696667 5 Migliorança MR Coppedê A Diaz Rezende RCL Mayo T Restoration of the edentulous maxilla using extrasinus zygomatic implants combined with anterior conventional implants: a Retrospective Study Int J Oral Maxillofac Implants 2011 26 665 72 21691615 6 Aparicio C A proposed classification for zygomatic implant patients based on the zygoma anatomy guided approach (ZAGA): a cross-sectional survey Eur J Oral Implantol 2011 4 269 75 22043470 7 Aparicio C Ouazzani W Hatano N The use of zygomatic implants for prosthetic rehabilitation of the severely resorbed maxilla Periodontol 2000 2008 47 162 71 18412580 8 Chrcanovic BR Albrektsson T Wennerberd A Survival and complications of zygomatic implants: an update systematic review J Oral Maxillofac Surg 2016 74 1949 64 27422530 9 Fernández H Gómez-Delgado A Trujillo-Saldarriaga S Varón-Cardona D Castro-Núñez J Zygomatic implants for the management of the severely atrophied maxilla: a retrospective analysis of 244 implants J Oral Maxillofac Surg 2014 72 887 91 24576439 10 Aparicio C Manresa C Francisco K Aparicio A Nunes J Claros P Zygomatic implants placed using the zygomatic anatomy-guided approach versus the classical technique: a proposed system to report rhinosinusitis diagnosis Clin Implant Dent Relat Res 2014 16 627 42 23464749 11 Molinero-Mourelle P Baca-Gonzalez L Gao B Saez-Alcaide LM Helm A López-Quiles J Surgical complications in zygomatic implants: a systematic review Med Oral Patol Oral Cir Bucal 2016:1 21 e751 7 27694789 12 Guennal P Guiol J Use of buccal fat pads to prevent vestibular gingival recession of zygomatic implants J Stomatol Oral Maxillofac Surg 2018 119 161 3 29107123 13 Yates JM Brook IM Patel RR Wragg PF Atkins SA El-Awa A Treatment of the edentulous atrophic maxilla using zygomatic implants: evaluation of survival rates over 5-10 years Int J Oral Maxillofac Surg 2014 43 237 42 24120903 14 Al-Nawas B Wegener J Bender C Wagner W Critical soft tissue parameter of the zygomatic implant J Clin Periodontol 2004 31 497 500 15191582 15 El Haddad SA Abd EL Razzak MY El Shall M Use of pedicle buccal fat pad in root coverage of severe gingival recession defect: case report J Periodontol 2008 79 1271 9 18597611 16 De Moraes JE The buccal fat pad flap: an option to prevent and treat complications regarding complex zygomatic implant surgery. preliminary report Int J Oral Maxillofac Implants 2012 27 905 10 22848893 17 Amin MM Laskin DM Prophylactic use of indomethacin for prevention of postsurgical complications after removal of impacted third molars Oral Surg Oral Med Oral Pathol 1983 55 448 51 6575332 18 Gutierrez S Wuesthoff C Testing the effects of long-acting steroids in edema and ecchymosis after closed rhinoplasty Plast Surg (Oakv) 2014 22 83 87 25114618 19 Hwang P Irwin S Griest S Caro J Nesbit G Radiologic correlates of symptom-based dignostic criteria for chronic rhinosinusitis Otolaryngol Head Neck Surg 2003 128 489 96 12707650 20 Aparicio C Manresa C Francisco K Claros P Alández J González-Martín O Zygomatic implants: indications, techniques and outcomes, and the zygomatic success code Periodontol 2000 2014 66 41 58 25123760 21 Esposito M Barausse C Balercia A Pistilli R Ippolito DR Felice P Conventional drills vs piezoelectric surgery preparation for placement of four immediately loaded zygomatic oncology implants in edentulous maxillae: results from 1-year split-mouth randomised controlled trial Eur J Oral Implantol 2017 10 147 58 28555205 22 Kan JY Rungcharassaeng K Lozada JL Zimmerman G Facial gingival tissue stability following immediate placement and provisionalization of maxillary anterior single implants: a 2- to 8-year follow-up Int J Oral Maxillofac Implants 2011 26 179 87 21365054 23 Chackartchi T Romanos G E, Sculean A. Soft tissue-related complications and management around dental implants Periodontol 2000 2019 81 124 38 31407443 24 Monika K Sunkala L Sandeep N Keerthi K Bharathi BV Madhav GV Evaluation of root coverage with pedicled buccal fat pad in class III and class IV gingival recession defects J Family Med Prim Care 2020 9 1656 61 32509667 25 Deepa D Arun Kumar KV Clinical evaluation of Class II and Class III gingival recession defects of maxillary posterior teeth treated with pedicled buccal fat pad: A pilot study Dent Res J (Isfahan) 2018 15 11 16 29497442 26 Araújo RT Sverzut AT Trivellato AE Sverzut CE Retrospective analysis of 129 consecutive zygomatic implants used to rehabilitate severely resorbed maxillae in a two-stage protocol Int J Oral Maxillofac Implants 2017 32 377 84 27632155 27 Chana H Smith G Bansal H Zahra D A Retrospective cohort study of the survival rate of 88 zygomatic implants placed over an 18-year period Int J Oral Maxillofac Implants 2019 34 461 70 30883622 28 Aleksandrowicz P Kusa-Podkańska M Grabowska K Kotuła L Szkatuła-Łupina A Wysokińska-Miszczuk J Extra-sinus zygomatic implants to avoid chronic sinusitis and prosthetic arch malposition: 12 years of experience J Oral Implantol 2019 45 73 8 30074849 29 Goiato MC Pellizzer EP Moreno A Gennari-Filho H dos Santos DM Santiago Jr JF Implants in the zygomatic bone for maxillary prosthetic rehabilitation: a systematic review Int J Oral Maxillofac Surg 2014 43 748 57 24530034 30 Aparicio C Manresa C Francisco K Ouazzani W Claros P Potau JM The long-term use of zygomatic implants: a 10-year clinical and radiographic report Clin Implant Dent Relat Res 2014 16 447 59 23078128