Denton Lanakila Thomas graduated from the University of Texas at Austin (Doctor of Musical Arts, Master of Music) and the University of Missouri-Columbia (Bachelor of Musical Arts Cum Laude). He is a member of Phi Mu Alpha Sinfonia and Pi Kappa Lambda. His primary teachers were Nathaniel Brickens and Troy Marsh, but he took additional study with trombonists and pedagogues including Bill Watrous, Paul McKee, Jim Widner, Charles Vernon, Randy Hawes, Eric Klay, Michael Bertoncello, and others.

Between 2003 and 2008, Dr Thomas lived in Austin, Texas, the Live Music Capital of the World. He instructed university and secondary trombone students, performed with Rick White's Monster Big Band, one of the most active big bands in Austin, and worked with various small ensembles in commercial and traditional styles. Outside Austin, he performed with the Jim Widner Big Band alongside trombonist Paul McKee and pianist Shelly Berg. He also worked and performed in fine-art festivals and camps including the Interlochen Center for the Arts, the Texas Music Festival, and the Missouri Summer Band Institute.

Dr Thomas' 2008 research on focal embouchure dystonia made an early effort to collect major medical research on the disease and distribute it to musicians in an informative and clear manner. As of 2016, it remains one of very few works that address the need to provide diagnosis pathways to pedagogues and performers.

Dr Thomas' music has been performed at the International Trombone Festival, the University of Texas at Austin, the University of Missouri, the University of Melbourne, and by professional ensembles in the USA and Australia. His compositions and arrangements primarily include chamber and solo works prominently displaying the trombone and other brass.

Dr Thomas has presented brass-focused master classes and lectures at conferences and schools in both Australia and the United States, and he has appeared multiple times at the Melbourne School Bands Festival (now Victoria School Music Festival) as a jazz and concert band adjudicator, brass tutor, and event administrator. He has performed in Melbourne with the Grainger Wind Symphony, Dizzy's Big Band, Esstee Big Band, Kew Brass Band, CLOC Theatre Company Orchestra, the Melbourne University Trombone Choir, and others. His teaching posts in Melbourne have included the Carey Grammar School, Yarra Valley Grammar School, Fintona Girls' School, and Camberwell High School.

Dr Thomas is a past National Secretary of the Australian Band and Orchestra Directors Association (ABODA), and he has been an operations and event administrator assisting the Association of Music Educators (aMuse) in the organization and delivery of multiple conferences and events for musicians and music educators.

Dr Thomas is currently on the brass teaching staff of Monash University, and he maintains a full-time position at Wesley College Glen Waverley (Secondary) teaching brass, IB Music, and conducting the Senior Symphonic Band. He and his family live and work in Melbourne.