Parvini et al. International Journal of Implant Dentistry (2019) 5:13 International Journal of https://doi.org/10.1186/s40729-019-0165-7 Implant Dentistry REVIEW Open Access Decision-making in closure of oroantral communication and fistula Puria Parvini1, Karina Obreja1* , Amira Begic1, Frank Schwarz1,2, Jürgen Becker2, Robert Sader3 and Loutfi Salti1 Abstract After removal of a dental implant or extraction of a tooth in the upper jaw, the closure of an oroantral fistula (OAF) or oroantral communication (OAC) can be a difficult problem confronting the dentist and surgeon working in the oral and maxillofacial region. Oroantral communication (OAC) acts as a pathological pathway for bacteria and can cause infection of the antrum, which further obstructs the healing process as it is an unnatural communication between the oral cavity and the maxillary sinus. There are different ways to perform the surgicalclosureoftheOAC.Thedecision-making in closure of oroantral communication and fistula is influenced by many factors. Consequently, it requires a combination of knowledge, experience, and information gathering. Previous narrative research has focused on assessments and comparisons of various surgical techniques for the closure of OAC/OAF. Thus, the decision-making process has not yet been described comprehensively. The present study aims to illustrate all the factors that have to be considered in the management of OACs and OAFs that determine optimal treatment. Keywords: Oroantral, Fistula, Flaps, Grafts, Maxillary sinus, Complication management, Oral surgery, Decision, Oroantral communication Background communication, time of diagnosis, presence of infection, Oroantral communication (OAC) acts as a pathological and clinician’s experience. Moreover, the selection of pathway for bacteria and can cause infection of the an- management strategy is influenced by the quantity and trum, which further obstructs the healing process as it is quality of tissue available for closure of OAF/OAC and an unnatural communication between the oral cavity and the potential placement of dental implants in the future the maxillary sinus. The oroantral fistula (OAF) develops if [3]. The method presented is decision tree design. This the OAC remains open and becomes epithelialized. The approach enables to recognize uncertainty in clinical oroantral fistula has its origin either from iatrogenic diagnosis and therapeutic decisions and hence develop complications or from dental infections, trauma, radiation strategies to manage these uncertainties. The present therapy, or osteomyelitis [1]. study aims to illustrate all the factors that have to be Clinical decision-making determines the optimal strategy considered in the management of OACs and OAFs that in a particular clinical situation. Consequently, it requires a determine optimal treatment. combination of knowledge, experience, and information gathering. Previous narrative research has focused on as- sessments and comparisons of various surgical techniques Etiology for closure of OAC/OAF [2]. Thus, the decision-making Identifying the etiology of the OAC is essential to create process has not yet been described comprehensively. an effective procedure. Harrison demonstrated that the Clinical decision-making in closure of an OAC/OAF bone lamella between the maxillary posterior teeth and depends on multiple factors that include the size of the the maxillary sinus is occasionally 0.5 mm [4]. Thus, the first premolars accounted for 5.3% of OACs, the second molars were the most frequently with an incidence of * Correspondence: [email protected] 45%, followed by the third molars 30% and the first 1Department of Oral Surgery and Implantology, Carolinum, Goethe University, Frankfurt, Germany molars 27.2%. It was reported that about 2.2% of the first Full list of author information is available at the end of the article molars apices perforated the maxillary sinus floor, © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Parvini et al. International Journal of Implant Dentistry (2019) 5:13 Page 2 of 11 followed by the second molars 2% of the described cases [4]. closure of OAC. Cardiovascular disease, diabetes, renal Due to the close relationship of the roots to the antrum and dysfunction, and hematological disorders may increase partially very thin maxillary sinus floor, the extraction of the the risk of complications such as bleeding, infections, upper molars and premolars, especially the extraction of the and delayed tissue healing [9]. first molars, is considered the most common etiology of OAC [5–7]. Pathological lesions in the sinus, trauma, and Signs and symptoms failed external sinus floor elevation and augmentation can The symptoms of an OAC can vary from purulent also lead to the formation of an OAC. Oroantral communi- discharge through the fistula to the patient’s subjective cation may be developed as a result of prevalence of the feeling entry of oral liquids into the nostril on the same inflammatory odontogenic pathologic processes through the side of the maxillary [10].Thepresenceofoneormoreof maxillary alveolar process to the Schneiderian sinus mem- the symptoms could be the indicator of an OAC or a fis- brane. Periodontal infections and other factors are the least tula (acute, chronic). However, some patients may not prevalent. Further complications of OAC may result from present any of these findings if the perforation is too small the removal of cysts or tumors, implant placement, maxillo- or closed by a large polyp. Untreated defect can cause facial surgery (Le Fort osteotomies), and pathological proce- sinus contamination leading to infection, chronic sinusitis, dures like osteomyelitis. In addition to the size of the defect, and impeded healing [10]. A confirmatory and early diag- possible maxillary sinusitis, odontogenic infections, cysts, nosis is therefore strongly recommended to permit tumors, foreign bodies in the maxillary sinus, and osteitis successful closure. and osteomyelitis changes also likely play a crucial role in the Figure 2 demonstrates symptoms based on whether formation of a chronic oroantral fistula. Furthermore, the OAC is acute OAF or chronic OAF. improper treatment of OAC can produce maxillary sinusitis and become chronic [8]. Figure 1 illustrates the etiologic Clinical examination and diagnosis factors of OAC/OAF/chronic OAF. Diagnosis represents the first decision-making about the pa- tient. It determines all subsequent treatments and the course Medical history of each patient. It mainly based on a comprehensive evalu- Medical history serves to identify patients who have a ation of dental and medical examination and patient history, higher risk to develop complications during or after specifically looking for diagnostic criteria for maxillary Fig. 1 Represents etiology of OAC, OAF, and chronic OAF Parvini et al. International Journal of Implant Dentistry (2019) 5:13 Page 3 of 11 Fig. 2 Illustrates steps of decision-making in symptoms of OAC, OAF, and chronic OAF sinusitis. Figure 3 illustrates the steps of decision-making in noting that the detection of small perforations is not always the diagnosis of antral perforation. possible [11]. Procedure Cheek-blowing test Intraoral examination The patient is asked to blow air into the cheeks against a The large OAC is easily seen on the investigation (Fig. 4). At closed mouth. This test is considered a risk of antral compli- a later stage, the antral polyp is seen through the defect. cations due to the spread of microorganisms from the oral cavity into the maxillary sinus. Valsalva test The patient is instructed to try to exhale through a Exploration of the perforation with probing blocked nasal airway. However, a negative test does not Attempt of probing the fistula is likely to result in sinus- exclude the possibility of antral perforation. It is worth itis or widening of the fistula due to pushing of foreign Parvini et al. International Journal of Implant Dentistry (2019) 5:13 Page 4 of 11 Fig. 3 Illustrates steps of decision-making in diagnosis of antral perforation bodies or bacteria into the maxillary sinus. [12]. Further- of the antral anatomy well because of the complexity of more, probing may lead to laceration of the sinus its anatomy [13]. membrane, which may sometimes be intact. Radiologically, bone discontinuity of the floor of the maxillary sinus is evident. Patients with OAF are most susceptible to sinus infections. Therefore, radiological Radiographic features of OAC and OAF investigation of the maxillary sinus is recommended. Radiological investigation of the site of OAC and OAF is Periapical film or panoramic radiography can provide an required to validate the clinical findings and to investi- idea about the bony defect size of the OAC and OAF. gate the presence of foreign body within the antrum. Radiologically, they reveal the disruption of the border From an anatomical point of view, several different of sinus. Periapical radiograph provides detailed infor- radiographic investigations are required to show all areas mation about the bony radiographic changes owing to Parvini et al. International Journal of Implant Dentistry