When Gibbs and Allison Hart are talking after entering to find Alfonso, Gibbs turns and closes the door with an audible click after Tony had kicked the door open breaking the latch.
When the team visits the scene of the car explosion, and Gibbs sets out evidence markers, in some shots he has a stack of them on his forearm, in others he is holding them in his hand. The location switches back and forth several times.
Very few dentist offices would have cobalt units. They were used many years ago for radiation therapy; never for diagnostic imaging.
While McGee and Ziva interview a dentist, he wears a shirt with a button-down collar; however, both collar buttons remain unfastened. Later, though, when McGee shows a photograph to Gibbs, the dentist wears the same shirt with both collar buttons fastened.
When McGee is on the online wedding he is in a black tuxedo, however when they next show him at the crime scene his pants are gray.
In the initial squad room scene, whilst McGee is attending the online wedding, a man in a green shirt walks down the stairs in the background three times without ever being seen go up.
Ziva calls the explosive 'Acetone Hydroxide' - It's not an explosive, but Acetone Peroxide is.