Clinical Studies



  1. Lill Y, Cespedes WV, Benitez BK, Eckstein-Halla NC, Leitmeyer KS, Gürtler N, Stieger C, Mueller AA, Screening for congenital hearing impairment with brainstem evoked response audiometry in isolated orofacial cleft, International Journal of Oral and Maxillofacial Surgery,
  2. Eckstein-Halla N, Filippi C, Müller AA. Lippen-Kiefer-Gaumen-Spalten. In: Filippi A Filippi C Neuhaus KW Quintessenz Verlags-GmbH. Die Zahnmedizinische Behandlung Von Menschen Mit Special Needs. 1. Auflage 2024 ed. Berlin: Quintessenz Verlag; 2024.
  3. Meyer S, Benitez BK, Thieringer FM, Mueller A A. 3D-printable Open-source Cleft Lip and Palate Impression Trays – A Single-Impression-Workflow. Plastic and Reconstructive Surgery, May 15, 2023.  DOI: 10.1097/PRS.0000000000010684 
  4. Benitez BK, Brudnicki A, Surowiec Z, Wieprzowski L, Rasadurai A, Nalabothu P, Lill Y, Mueller AA.
    Digital Impressions from Newborns to Preschoolers with Cleft Lip and Palate: A Two-Centers Experience.
    Journal of Plastic, Reconstructive & Aesthetic Surgery. 2022.
  5. Zarean P, Zarean P, Thieringer FM, Mueller AA, Kressmann S, Erismann M, Sharma N, Benitez BK. A Point-of-Care Digital Workflow for 3D Printed Passive Presurgical Orthopedic Plates in Cleft CareChildren. 2022; 9(8):1261.
  6. Benitez BK, Weibel SK, Halbeisen FS, Lill Y, Nalabothu P, Tache A, Mueller AA. Craniofacial Growth at Age 6–11 Years after One-Stage Cleft Lip and Palate Repair: A Retrospective Comparative Study with Historical Controls. Children. 2022; 9(8):1228.
  7. Reinhold A, Meyer P, Bruder E, Soleman J, von der Weid N, Mueller AA, Savic M, Congenital orbital teratoma: A clinicopathologic case report. American Journal of Ophthalmology Case Reports, 2022; 26,
  8. Benitez BK, Brudnicki A, Surowiec Z, Singh RK, Nalabothu P, Schumann D, Mueller AA, Continuous Circular Closure in Unilateral Cleft Lip and Plate Repair in One Surgery, Journal of Cranio-Maxillofacial Surgery, 2021; 50(1),

    In this retrospective, descriptive cohort study wound healing and safety of single-stage two-layers continuous closure in patients with unilateral cleft lip and palate (UCLP) is assessed.
    Wound healing without fistula formation at 1, 3, and 6 months after a single-stage two-layer UCLP repair, in which the midline suture is continuously circular all along the oral and nasal sides is evaluated. We examined lengths of hospital stay and the incidence of intra- and postoperative adverse events. Furthermore, we compared the cleft width at birth and on the day of surgery, after presurgical orthopaedics. These preliminary results shows potential of the concept of single-stage continuous circular closure in UCLP for further investigation. In particular, it remains to be proven that there are no relevant adverse effects such as inhibition of maxillary growth. 
  9. Benitez B, Brudnicki A, Nalabothu P, von Jackowski J, Bruder E, Mueller AA. Histologic aspect of the curved vomerine mucosa in cleft lip and palate. The Cleft Palate-Craniofacial Journal 2021; Volume 59, Issue 8.

    Here, we report our histological analysis on the curved vomerin mucosa from 8 patients during surgical repair of cleft lip and palate at 8 months of age. The result from the mucoperiosteum overlying the curved vomer revealed characteristics consistent with those of an oral mucosa or a squamous metaplasia of the nasal mucosa. The vomer mucosa showed no specific signs of nasal mucosa. These findings can be considered in presurgical cleft orthopedics and palatal surgery for further refinement. Shifting the vomer mucosa according to important aspects of cleft repair such as primary healing and establishing optimal form and function of palatal roof and nasal floor should overrule a fixed physiologic belief commonly implemented in surgical techniques.

  10. Ureel M, Augello M, Holzinger D, Wilken T, Berg BI, Zeilhofer HF, Millesi G, Juergens P, Mueller AA. Cold Ablation Robot-Guided Laser Osteotome (CARLO®): From Bench to Bedside. J. Clin. Med. 2021, 10(3), 450; 

    We present here our experiences of the first-in-man use of the Cold Ablation Robot-guided Laser Osteotome (CARLO®), a stand-alone robot-guided laser system has been developed by Advanced Osteotomy Tools. A patient underwent bimaxillary orthognathic surgery. A linear Le Fort I midface osteotomy was digitally planned and transferred to the CARLO® device. The linear part of the Le Fort I osteotomy was performed autonomously by the device under direct visual control. All pre-, intra-, and postoperative technical difficulties and safety issues were documented. Accuracy was analyzed by superimposing pre- and postoperative computed tomography images. The CARLO® device performed the linear osteotomy without any technical or safety issues. There was a maximum difference of 0.8 mm between the planned and performed osteotomies, with a root-mean-square error of 1.0 mm. The patient showed normal postoperative healing with no complications. The CARLO® device could be a useful alternative to conventional burs, drills, and piezosurgery instruments for performing osteotomies. 

  11. Holzinger D, Ureel M, Wilken T, Mueller AA, Schicho K, Milles G, Juergens P. First-in-man application of a cold ablation robot guided laser osteotome in midface osteotomiesJ Cranio-Maxillofac Surg. Volume 49, Issue 7, July 2021, Pages 531-537;

    In this report we describe the effective and successful routine use of Cold ablation robot-guided laser osteotomy CARLO® (AOT Advanced Osteotomy Tools, Basle, Switzerland) in an actual clinical setting. CARLO® is an integrated system, functionally comprising: an Er:YAG laser source, intended to perform osteotomies using cold laser ablation, a robot arm that controls the position of the laser source, an optical tracking device that provides a continuous and accurate measurement of the position of the laser source and of reference elements attached to instruments or bones, a navigation system (software) that is able to read preoperatively defined planned osteotomies, and – under the control of a surgeon – performs the planned osteotomies. It is a promising technical innovation that has the potential to set new standards for accuracy and safety in orthognathic surgery.
  12. Patient Reported Outcome Measurement: CLEFT-Q©, Children and Young Adults. Authored by Drs. Anne Klassen and Karen Wong. McMaster University, Canada. German (CH) Version 2020. Translated by Bilger S, Müller A, Indri I, Mueller AA, University Hospital Basel.

    The CLEFT-Q is a patient-reported outcome measure for patients with cleft lip and/or palate. The 12 CLEFT-Q scales measuring appearance (i.e., face, nose, nostrils, lips, cleft lip scar, teeth, and jaws), function (i.e., speech), and health-related quality of life (i.e., psychological, school, social, and speech-related distress) were field tested in a cross-sectional study in 30 centers in 12 countries. The report vary significantly with cleft type. Visualizing multiple outcomes simultaneously with radar charts allows for an understanding of a patient's overall status in a single graph.

  13. Weibel Seraina. Schädelwachstum nach frühem Komplettverschluss einseitiger Lippen-, Kiefer- Gaumen- Segelspalten in einer Operation mittels Stiellappen nach Veau. 2020. Doctorate Dental Medicine, University of Basel. Supervised-student-publication by Mueller AA.

  14. Nalabothu P, Benitez BK, Dalstra M, Verna C, Mueller AA. Three-Dimensional Morphological Changes of the True Cleft under Passive Presurgical Orthopaedics in Unilateral Cleft Lip and Palate: A Retrospective Cohort StudyJ Clin Med. 2020;9(4):962.

    Using a new analysis method based on three-dimenstional standardized reproducible landmarks, we have quantified the morphological changes in the palatal cleft and true cleft areas induced by passive plate therapy. We emphasize the importance of reproducibility and reliability of the anatomical points to establish a valid measuring method.
    (Freiwillige Akademische Gesellschaft (FAG), Basel, Switzerland)
    EACMFS presentation

  15. Can Esad. Erstellung eines digitalen Diagnoseregisters und Erfassung der dreidimensionalen Ausgangsbefunde für die elektronische Patientenakte bei Lippen-, Kiefer- und Gaumenspalten am Behandlungszentrum des Universitätsspital Basels. 2019. Doctorate Dental Medicine, Esad Can, University of Basel. Supervised-student-publication by Mueller AA.

  16. Walter C, Müller AA, Schmidt JC. Hirnabszess als lebensbedrohliche Komplikation einer unbehandelten schweren Parodontitis ? Parodontologie. 2019;30(4):367-386.

    This case report describes a systematic periodontal therapy of a patient suffered from a brain abscess caused by severer generalized chronic periodontitis (Type IIB). Here, the importance of periodontal health for the prevention of life-threatening medical complications such as a brain abscess is highlighted. Due to the interdisciplinary treatment approach in this reported case, recurrence of brain abscesses and further tooth extractions was be avoided in addition to establishment and maintainance of periodontal health over a period of more than 10 years.

  17. Beiglboeck F, Thieringer FM, Scherrer G, Mueller AA. 3D-printing for orthopedic treatment of infants with cleft lips and palate deformitiesInt J Oral Maxillofac Surg. 2019;48:5.

    Since its introduction by McNeil in 1954, infant orthopedic treatment of cleft lip and palate deformities has undergone a development into various directions. Various plate designs enable different improvements of cleft morphology and oral function to be achieved and their timing of the application might be restricted either to before lip surgery or extend for several years. Today 3D printing is assuming an indispensable role in the toolbox of surgery and dentistry. We present here a stepwise workflow using on-the-spot medical 3D-printing which renders as simple, fast and cost-effective to build infant orthopedic plates.

  18. Kansy K, Mueller AA, Mücke T, Koersgen F, Wolff KD, Zeilhofer HF, Hölzle F, Pradel W, Schneider M, Kolk A, Smeets R, Acero J, Haers P, Ghali GE and Hoffmann J. A worldwide comparison of the management of surgical treatment of advanced oral cancerJ Cranio-Maxillofacial Surg. 2018;46(3):511-520.

    Microvascular surgery following tumor resection has become an important field of oral and maxillofacial surgery (OMFS). This paper presents the results of the survey over management of T3/T4 maxillary and mandibular alveolar process and tongue squamous cell carcinoma (SCC) in German-speaking countries, Europe, and worldwide. Results from treatment strategies for T3/T4 tumors underline the limited evidence for the appropriate amount of resection and subsequent reconstruction process. Specific concepts for the management of resection and reconstruction of T3/T4 SCC of the maxillary and mandibular alveolar process and tongue are presented.

  19. Kansy K, Mueller AA, Mücke T, Koersgen F, Wolff KD, Zeilhofer HF, Hölzle F, Pradel W, Schneider M, Kolk A, Smeets R, Acero J, Haers P, Ghali GE and Hoffmann J. A worldwide comparison of the management of T1 and T2 anterior floor of the mouth and tongue squamous cell carcinoma – Extent of surgical resection and reconstructive measuresJ Cranio-Maxillofacial Surg. 2017;45(12):2097-2104.

    Microvascular surgery following tumor resection has become an important field of oral maxillofacial surgery (OMFS). The Study presents results of survey concerning treatment strategies for resection and reconstruction in OMFS collected from German-speaking countries, Europe and worldwide. According to the results, there is a need for a common guideline, and this paper presents specific concepts for the management of resection and reconstruction of T1/T2 squamous cell carcinoma of the anterior floor of the mouth and tongue.

  20. Berg B-I, Mueller AA, Augello M, Berg S, Jaquiéry C. Imaging in Patients with Bisphosphonate-Associated Osteonecrosis of the Jaws (MRONJ)Dent J. 2016;4(3):29.

    Bisphosphonate-associated osteonecrosis of the jaws (MRONJ/BP-ONJ/BRONJ) is a commonly encountered disease. During recent decades, there has been major advances in diagnostics. When MRONJ is suspected, a thorough clinical examination and radiological imaging are essential. In this paper we present the latest clinical update on the imaging options in regard to MRONJ: X-ray/Panoramic Radiograph, Cone Beam Computed Tomography (CBCT) and Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Nuclear Imaging, Fluorescence-Guided Bone Resection. The choice of image modality depends not only on the surgeon’s/practitioner’s preference, but also on the availability of imaging modalities. A three-dimensional imaging modality is desirable, and in severe cases necessary, for extended resections and planning of reconstruction.

  21. Brand S, Zimmerer S, Kalak N, Von Planta S, Schwenzer-Zimmerer K, Mueller AA, Zeilhofer HF, Holsboer-Trachsler E. Compared to controls, patients with ruptured aneurysm and surgical intervention show increase in symptoms of depression and lower cognitive performance, but their objective sleep is not affected. World J Biol Psychiatry. 2015;16(2):96-105.

    Patients with aneurysmal subarachnoid haemorrhage (aSah) have impaired sleep and cognitive performance together with more difficulties in social and everyday life along with hypocortisolism. However, a study assessing all dimensions between aSah severity, objective and subjective sleep, cortisol secretion, cognitive performance and social and everyday life has not so far been performed. The result of our comparative study between a sample of patients with aSah and a control group based on an assessment of these variables indicate that patients with aSah face psychological rather than physiological issues.
    (Basel Science Society)

  22. Vajgel A, Santos TDS, Camargo IB, De Oliveira DM, Laureano Filho JR, De Holanda Vasconcellos JR, Lima Jr. SM, Pereira Filho VA, Mueller AA, Juergens P. Treatment of condylar fractures with an intraoral approach using an angulated screwdriver: Results of a multicentre study. J Cranio-Maxillofacial Surg. 2015;43(1):34-42.

    This multicentre study aimed to investigate long-term subsequent radiographic and functional results after the treatment of condylar fractures using an angulated screwdriver system and open rigid internal fixation with an intraoral surgical approach. We show that Subcondylar or condylar neck fractures with medial or lateral displacement can be treated using an intraoral approach with satisfactory results, additionally with the advantages of the absent visible scarring, the avoidance of facial nerve injury, and the ability to obtain rapid access to the fracture.

  23. Kansy K, Mueller AA, Mücke T, Koersgen F, Wolff KD, Zeilhofer HF, Hölzle F, Pradel W, Schneider M, Kolk A, Smeets R, Acero J, Haers P, Ghali GE and Hoffmann J. Microsurgical reconstruction of the head and neck region: Current concepts of maxillofacial surgery units worldwide. J Cranio-Maxillofacial Surg. 2015;43(8):1364-1368.

    Microvascular surgery following tumor resection has become an important field of oral maxillofacial surgery (OMFS). Following the surveys on current reconstructive practice in German-speaking countries and Europe, this paper presents the third phase of the project when the survey was conducted globally. The DOESAK questionnaire has been developed via a multicenter approach with maxillofacial surgeons from 19 different hospitals in Germany, Austria and Switzerland. The study proves DOESAK questionnaire to be a valid and well accepted tool for gathering information about current practice in reconstructive OMFS surgery. The questionnaire has been able to demonstrate similarities, differences and global inequalities.

  24. Augello M, Berg B-I, Mueller AA, Schwenzer-Zimmerer K. Two case reports with literature review of the EEC syndrome: Clinical presentation and managementCase Reports in Plastic Surgery and Hand Surgery. 2015; 2(3-4):63-66.

    We report on siblings who suffer from EEC syndrome and show our experiences of the "Basel concept" of cleft lip/palate repair based on the early, one-stage closure of all components. It is performed in the age of 3–4 months to provide early normal conditions for anatomy and muscle function. These two reports demonstrate the management of EEC syndrome affected patients with “all-in-one” closure of the lip cleft and palate cleft and the treatment regimen in manifest ectodermal dysplasia.

  25. Mueller AA, Neue Verfahren zur Wiederherstellung kiefer-gesichtschirurgischer Defekte, insbesondere bei Lippen-Kiefer-Gaumenspalten und nach Tumorresektionen. 2015, Postdoctoral Thesis, University of Basel, Faculty of Medicine.

  26. Kansy K, Mueller AA, Mücke T, Kopp J-P, Koersgen F, Wolff KD, Zeilhofer H-F, Hölzle F, Pradel W, Schneider M, Kolk A, Smeets R, Acero J, Hoffmann J,D€OSAK Collaborative Group for Microsurgical Reconstruction. Microsurgical reconstruction of the head and neck - Current concepts of maxillofacial surgery in EuropeJ Cranio-Maxillofacial Surg. 2014;42(8):1610-1613.

    Microvascular surgery following tumour resection has become an important field of oral maxillofacial surgery (OMFS). In Europe, it is a common and safe procedure. The study evaluates current microsurgical practice in Europe based on a survey with the questionnaire of DOESAK collaborative group for Microsurgical Reconstruction. While there is a major accordance for the surgical procedure itself and the most frequently used flaps, perioperative management, shows a wide variety of protocols with low presumed impact on surgical outcome.

  27. Mueller AA, Kalak N, Schwenzer-Zimmerer K, Holsboer-Trachsler E, Brand S. Cortisol levels and sleep patterns in infants with orofacial clefts undergoing surgeryNeuropsychiatr Dis Treat. 2014;10:1965-1972.

    Traumatic events during early infancy might damage infants’ psychobiological functioning, such as sleep and cortisol secretion. Infants born with orofacial clefts (OFCs) undergo functional, anatomical, and aesthetic surgery. The present study aimed to determine whether infants with OFC and undergoing OFC surgery show deteriorated sleep and cortisol secretion compared with healthy controls and with their presurgery status. The pattern of results for sleep and cortisol level among infants with OFC undergoing corrective surgery suggests that OFC surgery does not seem to constitute a traumatic event with long-term consequences.
    (Gottfried and Julia Bangerter-Ryhner Foundation, Austrian Cleft Palate Craniofacial Association)

  28. Mueller, AA. Complementing surgical with biomedical and engineering methods to evolve lip and nose reconstruction. 2013, Doctoral Thesis, University of Basel, Faculty of Medicine.

  29. Mueller AA, Zschokke I, Brand S, Hockenjos C, Zeilhofer HF, Schwenzer-Zimmerer K. One-stage cleft repair outcome at age 6- to 18-years - A comparison to the Eurocleft study dataBr J Oral Maxillofac Surg. 2012;50(8):762-768.

    The optimisation of the relation between quality of outcome and burden of care is difficult in the treatment of cleft lip and palate. We analysed long-term outcome after one-stage repair of clefts to assess the benefits and limitations of this form of treatment. Patients who have had lip repair, two-flap palatoplasty, and corticocancellous alveolar bone grafts at 6 months of age were compared with mean outcome data from the Eurocleft centres and with cephalometric standards of healthy people. The study shows that the patients did ultimately benefit from a reduced number of surgical steps, since the total number of surgeries was halved compared to multi-stage procedures, while limiting the disturbance in growth to the degree similar to mean values of multistage procedures in the Eurocleft study.
    (Swiss Dental Association (SSO), Basel Science Society (FAG))

  30. Mücke T, Mueller AA, Kansy K, Hallermann W, Kerkmann H, Schuck N, Zeilhofer HF, Hoffmann J and Hölzle F. Microsurgical reconstruction of the head and neck-Current practice of maxillofacial units in Germany, Austria, and SwitzerlandJ Cranio-Maxillofacial Surg. 2011;39(6):449-452.

    Refinement in microvascular reconstructive techniques over the last 30 years has enabled an increasing number of patients to be rehabilitated for both functional and aesthetic reasons. This study evaluates current practice in reconstructive surgery and the different strategies including the perioperative management of microvascular cases in Germany, Austria, and Switzerland. A questionnaire developed by the DÖSAK collaborative group for Microsurgical Reconstruction to perform a survey. The result shows variation in the performance, management, and care of microsurgical reconstructions of patients. Consolidation of data into a national or an international database would seem logical to inform decision-making and also to allow meaningful analysis of unit performance.

  31. Brand, Serge; Mueller AA. Quality of life among children , adolescents and adults with orofacial clefts. In: International Encyclopedia of Rehabilitation. 2010.

    Generally, facial appearance is regarded as an important prerequisite for healthy psychosocial development. As a consequence, it might be anticipated that children, adolescents, and adults with untreated orofacial clefts (OFC) would be at risk for psychosocial difficulties. In this view, untreated OFC generally leads to negative effects on speech, hearing, appearance, and physical and psychological well-being. Studies concerning the relation between surgically repaired OFC and psychosocial difficulties indicate a negligible impact of cleft lip and palate (CLP) on an individual’s psychological well-being as well as selectively negative impact on quality of life. The results related to the quality of life of adults with OFC are also inconsistent, however the occurrence of repaired OFC does not necessarily lead to unfavourable psychosocial outcomes.

  32. Brand S, Blechschmidt A, Mueller AA, Sader R, Schwenzer-Zimmerer K, Zeilhofer HF, Holsboer-Trachsler E. Psychosocial functioning and sleep patterns in children and adolescents with cleft lip and palate (CLP) compared with healthy controlsCleft Palate-Craniofacial J. 2009;46(2):124-135.

    This study aimed to assess psychological functioning, interactional competencies, and sleep patterns in children and adolescents with cleft lip and palate (CLP), and to compare these results with those from age- and gender-matched controls. It was hypothesized that participants with CLP would exhibit greater difficulties in psychological functioning, more interactional difficulties, and poorer sleep patterns than those without CLP. Participants with and without CLP did not differ with respect to emotional problems, conduct problems, hyperactivity or unfavorable sleep patterns. With respect to interactional competencies, participants with CLP in adolescence were more likely to report difficulties. Consequently, skill training to improve context-related social competencies may be appropriate.

  33. Mueller AA, Saldamli B, Stübinger S, Walter C, Flückiger U, Merlo A, Schwenzer-Zimmerer K, Zeilhofer HF and Zimmerer S. Oral bacterial cultures in nontraumatic brain abscesses: results of a first-line studyOral Surgery, Oral Med Oral Pathol Oral Radiol Endodontology. 2009;107(4):469-476.

    Bacterial cultures from nontraumatic brain abscesses (BAs) frequently contain oral bacteria. We assessed bacterial cultures from BAs and oral infective sources for a bacterial match. The findings of the study shows the importance of early collaboration among neurosurgeons, infectious disease specialists, and oral-maxillofacial surgeons in the identification and treatment of suspected oral sources of nontraumatic BAs.

  34. Juergens P, Kim H, Kunz C, Beinemann J, Mueller AA, Schwenzer-Zimmerer K, Zeilhofer HF. Intraoperative three-dimensional real-time navigation in orthognathic surgeryInt J Oral Maxillofac Surg. 2009;38:5(474)

    Accurate preoperative planning of corrective surgery of deformities in the facial skeleton is essential for successful surgical treatment. Virtual three-dimensional (3D) models of the facial soft tissue and the underlying bony structures generated from computed tomography (CT) scans are used to perform relocation planning and soft tissue prediction. A navigation system consisting of a laptop computer linked to a POLARIS optical tracking system with passive markers and the software based on the MARVIN platform was used. The innovated 3D guidance interface enables the surgeons to reach their planned surgical goals in an intuitive way. The developed workflow was implemented in the clinical routine. The navigation system has been validated for the use in orthognathic surgery.

  35. Brand S, Mueller AA, Schwenzer-Zimmerer K, Sader R, Zeilhofer HF, Holsboer-Trachsler E. The impact of mother's behavior on infant's sleep before and after surgical intervention for cleft-lip-palate (CLP) repair. Archives of Disease in Childhood 2008;93(2):225.

  36. Mueller AA, Sader R, Honigmann K, Zeilhofer HF, Schwenzer-Zimmerer K. Central nervous malformations in presence of clefts reflect developmental interplay. Int J Oral Maxillofac Surg. 2007;36(4):289-295.

    Children with cleft lip and/or cleft palate (CLP) are often affected by additional congenital malformations. The relationship between CLP and the malformations is of special interest, as it could reflect interactions between or similarities in their pathogenetic mechanisms. This retrospective study investigated the incidence of additional malformations in CLP patients and how it differs from that of a cohort of live-borns from the general population. Altogether, the rise in malformation incidence among the CLP patients, when compared to the general population, was highest for organs of ectodermal and ecto-mesodermal origin. The result reflects the close interplay of craniofacial and brain development.
    (Margarete and Walter Lichtenstein Foundation)