Introduction: Karl Häupl is considered one of the most famous European dentists of the 20th century. The aim of this article is to trace the life and work of the Austrian university lecturer and to evaluate his professional contributions. An additional focus is put on Häupl’s role in the Third Reich.
Material and Methods: The methodological basis of the study is the evaluation of sources from various German and Austrian archives (some of which have been evaluated for the first time) and a critical re-analysis of the relevant research literature.
Results: The analysis demonstrates that Häupl was one of the most influential and effective university lecturers in dentistry and, in particular, one of the pioneers of functional orthodontics; this is fully in line with the contemporary assessment. In contrast, the classification of his role in the “Third Reich” is clearly discrepant: Although Häupl’s relationship to National Socialism was not addressed for decades, the archival sources provide clear evidence of political entanglement.
Discussion and Conclusion: The analysis of the relevant sources leads to the conclusion that in the Third Reich Häupl was politically true to the line. He did not only join the National Socialist Party, but also enjoyed the backing and support of the major Nazi networks in his chair applications (German University Prague, University Berlin), honours, and further initiatives.
PRWTH Aachen University, Medical School, Aachen: Prof. Dr. Dr. Dr. Dominik Groß
Citation: Groß D: Karl Häupl (1893–1960) – His life and works with special consideration of his role in the Third Reich. Dtsch Zahnärztl Z Int 2020; 2: 95–101
Peer-reviewed article: submitted: 23.12.2019, revised version accepted: 28.01.2020
Karl Häupl (1893–1960, Fig. 1) is, without a doubt, one of the most well-known European dentists in recent history. Considered to be a pioneer in the area of functional orthodontics, Häupl held numerous prestigious professional positions and he received many awards. He was the dean of the Medical Faculty at the University of Innsbruck, rector of the Medical Academy of Dusseldorf, he was awarded two honorary doctoral degrees, became an honorary citizen of his hometown, an honorary member of various international professional associations, and a selected member of the American College of Dentists – just to cite a few of his many achievements. In 1978, his name was posthumously ascribed to the “Karl Häupl Institute”, a renowned professional dental training establishment in Dusseldorf.
The aim of the present article is to reconstruct and professionally situate the life and work of this Austrian dentist. An additional focus is on Häupl’s role in the Third Reich. This investigation was carried out as part of the national project “Dentists and Dentistry under National Socialism”. The three-year research, which was completed in 2019, revealed the broad political commitment of German and Austrian dentists during this period. The year 2020 also marks the sixtieth anniversary of Häupl’s death.
Materials and Methods
The main sources used for this study are archival documents from the German Federal Archives in Berlin, the State Archives in Dusseldorf and the University Archives in Vienna. Additionally, a critical analysis of relevant international research findings on the life and works of Häupl was conducted, including contemporary professional debates about orthodontics and dentistry under National Socialism. A total of about 40 laudations, obituaries and other publications related to his person were identified and evaluated.
Karl Häupl – central biographical stations
Karl Häupl was born in Seewalchen am Attersee, Austria, on April 12, 1893 [9–12, 15, 39, 43–44, 47–48, 52]. His father (1865–1927), of the same name, was a local inn-keeper and the mayor of the town for a time. Häupl attended elementary school in the town of his birth and spent his secondary school years at the episcopal Petrinum Gymnasium, a private catholic school in the Linz diocese. He quickly came to receive recognition from his superiors for his industriousness and “extraordinary memory” . After obtaining his degree from the humanistic secondary school (gymnasium) in the town of Kremsmünster, Häupl went on to study human medicine at the University of Innsbruck in 1912, while his brother Josef was tasked with taking over the inn from their father . On account of the First World War, Häupl was forced to interrupt his medical studies in 1914, the year he was conscripted in the First Territorial Army Regiment. After being seriously injured during a battle in Poland in April 1915, Häupl was sent to serve at the division for orthodontic medicine at Clinical Reserve Hospital in Innsbruck.
In March 1919, Häupl obtained his license to practice medicine followed by an academic promotion to Doctor of Medicine in Innsbruck. He soon found a position at the Dental Institute of the University of Innsbruck under Bernhard Mayrhofer. He was promoted to First Assistant after just 6 months.
In 1920, Häupl moved to Norway, where he worked at various dental practices in Bergen and Oslo. He obtained a position as First Assistant at the Surgical Department of the Royal Dental College in Oslo in 1923, where he also became certified in the area of dental medicine. In 1924, he passed the dental medicine examination and received his license to practice medicine in Norway. A few years later, in 1927, Häupl attained a postdoctoral qualification (habilitation) – which was accompanied with a Norwegian M.D. title – as well as a lectureship. In 1929, he became the head of the Laboratory for Pathology at the Dental College in Oslo, and in 1931 professor for General and Specialized Dental and Maxillofacial Pathologies. At the end of 1930, Häupl married his first wife, the Norwegian Karen Hangsöen, with whom he had his first child in 1931 and his second in 1936 .
On October 1, 1934, Häupl became a full professor and the chair of the Clinic for Dental and Maxillofacial Diseases at the Germany University of Prague [41, 49, 55] in former Czechoslovakia. The Charles University of Prague, founded in 1348 by King Charles IV, was the oldest university in the “Holy Roman Empire of the German Nation”. In 1882, the university was divided into a German and a Czech university as a result of growing nationalism in Austria-Hungary. While in this position, Häupl played a key role in expanding the clinic. Starting in 1941, he was also appointed as a medical officer and as the head of the military hospital for patients with maxillofacial and facial injuries in Prague.
In 1943, his career experienced another significant leap forward when Häupl assumed the role of full professor and head of the department for Orthodontics and Dental Prosthetics at the Dental Institute of Berlin. Upon assuming this position, he succeeded the then recently deceased Hermann Schröder and, as of 1944, he assumed the role of director of the entire institute. Schröder was considered to be one of the most important university professor for dental medicine of his time, and the institute itself was the leading institution in Germany.
After the end of the war, Häupl returned to Austria. Here his brother Josef had served as mayor of Seewalchen during the NS era. Karl Häupl was unceremoniously offered a professorship in Innsbruck; he accepted and worked to rebuild the city’s dental institute . During this period, he declined numerous professorships at various German universities (Hamburg, Marburg and Freiburg) and at the University of Vienna . Though he did not accept the latter position in Vienna, Häupl did seek to influence the selection process by announcing his praise for candidates Hermann Wolf and Arthur Martin Schwarz while offering a negative assessment of Fritz Driak – who would ultimately assume the position: “The answer to the question of what lasting contribution Driak has made to dentistry cannot be anything positive” .
In 1951, Häupl took on a professorship for oral, jaw and dental medicine and maxillo-facial surgery at the West German Jaw Clinic of the Medical Academy of Dusseldorf [17, 37–38, 53]. As the West German Jaw Clinic was a leading institution in its area at the time, this was an extremely prestigious position [17, 38].
On June, 29 1960, Häupl passed away in Basel as a result of highly dramatic circumstances. While giving a speech to commemorate the 500th anniversary of the University of Basel in 1960, he suffered a heart attack and collapsed in front of the attendees and in front of his second wife, Katharina – an event that was subsequently mentioned in various obituaries and remembrances [39, 44, 52]. In his biography, Jüliger speculated that Häupl had suffered from the stress of a trip to the United States that he had just taken, having arrived in Basel at the last minute after the train he had been riding on derailed . Häupl’s second wife outlived him by 28 years, passing away in Seewalchen in 1988 (Fig. 2).
Häupl’s scientific oeuvre and his impact in the area of dental medicine
Together with the Norwegian dentist, Viggo Andersen, Häupl was the founder of internationally acclaimed practice of functional orthodontics [9–12, 39, 43, 45, 47, 48, 52, 56]. Functional orthodontics is a treatment concept that uses passive tooth-born appliances placed in the oral cavity to stimulate the soft and hard tissue of the masticatory (chewing) system to alter its muscular functional patterns and thereby react to adjustments and growth. Starting in the mid-1920s, both dentists entered the public spotlight with their concepts and devices, first in Oslo and later internationally, especially with the so-called “Andersen-Häupl Activator”. Häupl’s book, “Functional Jaw Orthodontics” (1936), co-authored with Viggo Andersen, quickly established itself as a standard reference work, with 6 different editions published up to 1957 . At the same time, Häupl emerged as a critic of the competing treatment concept based on “removable plates”. He engaged in a professional dispute with his colleague Martin Schwarz in Vienna on this issue, which did not, however, disrupt the personal “esteem and friendship” the two had for one another. Additionally, he also had a scientific disagreement with the no less influential orthodontist from Bonn Gustav Korkhaus about the risks and side effects of fixed orthodontic appliances [18, 42].
Besides functional orthodontics, Häupl also did research in the areas of periodontology as well as bone histology and pathology, accompanied by work on the periodontium and dental surgery. It was not without reason that, in 1957, Reichenbach cited Häupl one of his few remaining colleagues “with a mastery of the largely expanded area of dental, oral and jaw medicine and with the ability to excite and guide numerous specialists working in this area” .
In his lifetime, Häupl would author 150 publications, including 10 books. Along with the textbooks about functional orthodontics, 2 highlights include the development of his post-doctoral piece about marginal periodontitis (published in 1927 with Franz Josef Lang) and his book about dental crown and bridge work (published in 1929 with Ingjald Reichborn-Kjennerud), the second edition of which was published in 1938 under the title “Dental Crown and Bridge Work”. His histological studies about tissue remodeling and tooth displacement in functional orthodontic (1938), of tooth histopathology and the support brace (1940) and the two-volume textbook of dentistry (1949–1950, 2nd edition 1953) went on to become standard references in the area. One of Häupl’s final books was “Kieferorthopädie” (1959, 2nd edition 1963) and he also published a handbook about dental oral and orthodontic medicine, released as 6 volumes in 7 parts (published in 1955ff with Wilhelm Meyer and Karl Schuchardt) [31–36].
During his career, Häupl held numerous offices and received many honors and awards, only a small sample of which we are able to present here [9–12, 39, 43, 44, 47, 48, 52]: In the post-war era, he held the positions of senator and dean of the Medical Faculty of the University of Innsbruck in 1949, he was named honorary citizen of Seewalchen (his town of birth) in 1952, he was elected president of the German Working Group for Periodontics Research (ARPA, today known as the DGParo), he received an honorary doctoral degree from the University of Freiburg in 1958 and from the University of Halle/Saale in 1960, and he was selected as a member of the American College of Dentists in 1959. Häupl was a member of the German National Academy of Sciences Leopoldina and an honorary member of German, Austrian, Finish, Danish, Swedish, Norwegian and Italian professional associations. After his death, Häupl was buried in a grave of honor in the town of Seewalchen. In 1978 – 18 years after passing away – the Dental Association of Nordrhein founded the “Karl-Häupl Institute” in his honor, a professional training establishment in Dusseldorf.
Häupl had left a special mark on the city: After years of reform bottlenecks, he brought about a far-reaching reconstruction and expansion of the West German Jaw Clinic in Dusseldorf. Additionally, the pinnacle of his career came in 1957 when he assumed the position of rector there. Following Oskar Römer (1928), Johannes Reinmöller (1933) and August Lindemann (1948), this made Häupl only the fourth university professor of dental medicine that held this position at a German university.
Karl Häupl studied under influential academics, including Gustav Adolf Pommer (1851–1935), Arturo Hruska sen. (1880–1971) and Bernhard Mayrhofer (1868–1938). Häupl himself guided many of his own pupils to success, including Fritz Brosch (1903–1981), Josef Eschler (1908– 1969), Heinz Raab (1909–1987), Hans Wunderer (1912–1994) and Hubert Stöger (1913–1980) .
Häupl’s relation to National Socialism
There is no doubt that in the Third Reich (1) Häupl was looked upon as politically loyal to the line, and that (2) he enjoyed the support of his Nazi superiors. There is a wide range of formal and factual indications supporting this claim:
The first formal indication of this is the fact that the native-born Austrian became a member of the NSDAP after the “Anschluss” (annexation) of Austria to the German Reich which is documented in the Federal Archives [5, 7]. Though no specific date is given for his entry into the party, Häupl himself stated that he had submitted a request for membership into the NSDAP in April 1939, a statement that is also contained in the archives . This coincides with information from Míšková (2007): She noted (but without mentioning the primary source) that Häupl had been a member since 1.4.1939 and had received the party number 7,187,557 .
A second formal indication is offered by a term that Häupl himself chose to use: During his time in Prague, he referred to himself as “gottesgläubig” (believer in God) on a questionnaire that he filled out . “Gottesgläubig” was a term introduced and used by the Nazis, referring to an individual who was religious but had turned away from his church for political reasons – Häupl was originally a Protestant. The word served as “proof of ideological proximity to National Socialism” .
Besides, there are also a number of factual indications of Häupl’s commitment to the National Socialist party. One early piece of evidence is offered by Häupl’s successful bid to assume a professorship at the German University of Prague: the relationship between the adjacent German and Bohemian universities in Prague that existed since 1882 became politically very tense during this period, with nationalist radicalization occurring at both universities at the time. After the “Munich Agreement” from the fall of 1938, the German university officially renounced its loyalty to the Czechoslovakian state, just prior to the disintegration of the rest of Czechoslovakia by the Nazis in March 1939.
The German University of Prague became a (imperialistically oriented) prestige project for the Nazis following Hitler’s rise to power. Thus professorships at the German University were generally reserved for instructors loyal to the regime, as Míšková has described in detail . The fact that Häupl played a major role in the development of the German University for many years (1934–1943) underlines that he was seen as politically trustworthy. In his memoirs, the pathology professor Herwig Hamperl, who was working at the German University of Prague at the same time as Häupl, noted that he had been surrounded by colleagues with a National Socialist orientation , a circumstance he highlighted in order to justify his own NSDAP membership. Additionally, Häupl’s colleague and eventual successor in Dusseldorf, Carl-Heinz Fischer, also made direct reference to Häupl’s professorship in Prague. Fischer remembers the speech by the National Socialist “Reichszahnärzteführer” (Reich dentist leader) Ernst Stuck on the occasion of the DGZMK annual conference in 1938, which was “entirely under the influence of the Third Reich”. In the speech in question, Stuck spoke of Häupl’s role at the German University in Prague and described Häupl as a “man called up for this difficult task” . The support that Häupl enjoyed from his Nazi superiors is also illustrated by the fact that he was promoted to corresponding member of the politically centralized DGZMK the same year, 1938 .
From other files of the Federal Archives it is clear that Häupl was in exchange with both “Reichszahnärzteführer” Ernst Stuck and “zahnärztliche Reichsdozentenführer” (Chief Lecturer Dentist) Karl Pieper and that he could rely on the support of these two influential Nazis. Häupl had asked for support for Josef Eschler, his closest academic protégé and later successor in Prague, and obviously succeeded: On May 13, 1942, he thanked Pieper for his “outstanding services” in promoting Josef Eschler: “[...] I would like to take this opportunity to thank them very much for their commitment to Eschler at the time. Heil Hitler!” . At the beginning of 1940 Pieper had already arranged for Eschler to be appointed as a “Privatdozent” sooner than usual so that Eschler fulfilled the requirements to be appointed professor in Tokyo – this initiative was also preceded by a letter of request from Häupl (dated November 11, 1939) .
Another clear indication of Häupl’s political propinquity to the Nazi regime was his appointment as professor at Berlin in 1943. The Dental Institute in Berlin was the most prestigious institution of its sort under the Third Reich. As with the German University of Prague, only individuals with a National Socialist orientation who towed the party line were considered for eminent positions. This is evidenced by the circle of individuals ultimately considered for the corresponding professorship. Favored were “Reichsdozentenführer” Karl Pieper – adecorated “Blood Order” bearer and a glowing National Socialist with a very modest academic body of work [24, 29] who would ultimately turn down the position in favor of negotiations to remain at Munich –, Erwin Reichenbach, a member of the NSDAP and SA since 1933 [27, 50] and the candidate who was ranked first for this position, Karl Greve, a self-confessed National Socialist and Wehrmacht soldier, and Karl Häupl himself.
The fact that Häupl had particularly important advocates in the relevant Nazi networks was revealed in the further decision-making process: According to archive sources, Hermann Göring – the “Reich’s Marshal” and unquestionably one of the most important members of the National Socialist party – personally supported Häupl’s candidacy for the professorship [3, 5]. Specifically, the files state that “by order of the Reich’s Marshal” it was announced “that Professor Häupl from Prague would be appointed in place of the now deceased Professor Schroeder [...] His appointment should be carried out without debate.” In fact, Göring’s order was carried out, as the representative of the responsible ministry told him submissively: “Your wish and the scientific qualification of Professor Häupl were decisive for the appointment.” However, the ministerial representative did not fail to point out “that the Berlin faculty had not included Professor Häupl on the list”, since he “would not be considered as the successor of Professor Schröder for the subject of dental prosthetics, since his scientific research field was in a different area” .
In fact, even Professor Eugen Wannenmacher – official head of the dental press – had himself expressed his views on the appointment issue in letters, arguing against Häupl’s election for purely technical reasons: “Reichenbach and Greve have proven themselves as heads of prosthetic departments for years. These comparisons explain that Häupl could not be mentioned on the same level as Reichenbach and Greve on the list of appointments” . But Wannemacher‘s argumentation went unheard and Häupl was appointed.
The Berlin faculty was also unhappy with Göring’s demand that Häupl should become full professor – in contrast to the two other representatives of the Berlin Institute, Otto Hofer and Eugen Wannenmacher, who were only associate professors. The faculty argued as follows: “As the youngest representative of the subdivision brought to Berlin, he would be the only full professor. This means a great setback for the other two representatives of the subdivision.” But also in this point Göring stuck to his position .
One final piece of evidence indicating Häupl’s allegiance to National Socialism comes from 1944. In this year, Häupl was appointed by to the “Scientific Committee of Representatives for the Health System Karl Brandt”, a prestigious honor that was only granted to individuals who were loyal to the regime. Karl Brandt was one of the highest-ranking physicians in the context of the Nuremberg Doctors’ Trails: During the Third Reich, he served as SS Brigadeführer and General Major of the Waffen-SS as well as the General Commissioner for the Sanitary and Health System. It was probably against this background that Ernst Klee integrated Häupl in his frequently cited “encyclopaedia of persons” (Personenlexikon) of the Third Reich published in 2003. According to Klee, the encyclopaedia listed “the social elite in the time of the Third Reich” and those individuals “who always [resurface] in studies of the Nazi era” .
Häupl’s brother Josef, who had taken over their father’s inn, also placed himself at the service of National Socialism in the “Great German Reich”. As mentioned, he held the post of mayor of Seewalchen during the Nazi regime, for which he should be held accountable after the war: from 1945 to 1947 he was forced to shut down his traditional inn .
Discussion and Conclusions
Karl Häupl’s life deserves special attention for 3 principle reasons. First, an analysis of his writings and awards underscores Häupl’s very pivotal role in the area of academic dental medicine and especially orthodontics – contemporary and retrospective assessments are fully in accord on this matter. Second, Häupl led a notable life full of exceptional experiences with professional periods in 4 European countries (Norway, Czechoslovakia, Germany and Austria) – a life that ended abruptly and quite dramatically in 1960. Third, the reception of Häupl’s relationship to National Socialism was subject to a notable transformation. The findings about Häupl’s role in the Third Reich are clearly in strong contrast to the descriptions that were written about Häupl in post-war Germany as well as in the subsequent decades. For a long period of time, the predominant view about Häupl was largely uncritical and rather euphemistic. The question as to his relationship to National Socialism was simply ignored in his biographies – a phenomenon that also applied to the broader populace at this time, cum grano salis, and for the organized dental profession, which significantly contributed to delaying the entire process of coming to terms with the Nazi professional community [21, 22, 30, 51].
In particular, during the post-war years in Germany, Josef Eschler constructed a positive, almost hagiographic, depiction of his academic mentor Häupl via numerous lau-dations [9–12]: “Hard with himself and benevolent with his colleagues, he always tried to resolve every dispute amicably. His incredible spirit, his generosity and his great modesty attest to his true devotion to medicine and his humaneness” . The same applies for Jüliger, whose doctoral thesis was a biography of Häupl. Not one of the 135 pages of his work talks about Häupl’s role during the Third Reich. He neither makes mention of Häupl’s membership in the NSDAP nor does he address the issues related to his numerous appointments and professorships cited above . On the contrary, in reference to Häupl’s professorship in Prague, Jüliger fails to differentiate between the German and the Czech university there. According to him, Häupl’s appointment as professor at the German University of Prague (orchestrated by the Nazis) was allegedly an initiative taken on the part of the Czech university officials. The “University of Prague”, he writes, had “strong interest” in “winning [Häupl] for the position of clinic director.” Jüliger also offers a simplistic explanation for the professorship Häupl attained in Berlin (1943). “The high renown that Häupl enjoyed was honored with a professorship at the University of Berlin in 1943.” He does not even mention the fact that university professors such as Häupl, who joined the NSDAP, were removed from their positions by the Allies in 1945. Instead, Jüliger makes a veiled comment, simply stating that the “end of the Second World War in 1945 unfortunately saw the end of Häupl’s position in Berlin after just two years” .
Despite numerous archival requests, we have been unable to locate any Austrian denazification documents about Häupl. It is quite conceivable that Häupl succeeded in avoiding this process. Indeed, the provisional Austrian government allowed for exemptions from “mandatory registration” when the individual in question had not “abused” their NSDAP membership. This clause was expanded further and further over time until, eventually, 85 to 90 percent of those who would have had to register their membership attempted to appeal for an exemption, based on the argument that they had “never abused” their membership. This also applied to Häupl’s colleague in Prague Herwig Hamperl mentioned above, who, just like Häupl, went to Austria right after the war [16, 25].
The biographies about Häupl written by Eschler (1953–1960) and Jüliger (1988) likewise demonstrate that Häupl’s relation to National Socialism had not been addressed for many years, leading Häupl to be considered as a politically uninvolved individual. As recent studies have acknowledged, a very similar course of events can also be identified for other professors of dental medicine from this era, including Hermann Euler, Erwin Reichenbach, Reinhold Ritter, Guido Fischer and Fritz Faber [19, 20, 23, 27, 28]. Such thematic “omissions” might explain why the professional training institute in Dusseldorf was named after Karl Häupl in 1978, posthumously elevating him to prominence: people were simply unaware of Häupl’s political standing in the Third Reich; they also avoided asking any more far-reaching questions.
Conflicts of interest:
The author declares that there is no conflict of interest within the meaning of the guidelines of the International Committee of Medical Journal Editors.
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