The mandibular fracture line with involved teeth, because of the presence of periodontal ligament, is always in communication with the oral cavity and therefore may allow the spread of infection. Moreover, such a tooth may lose blood supply due to damage of apical blood vessels and in the case of pulp necrosis the tooth is a source of infection. Methods of sensitivity testing of teeth are based on pain and it is difficult to distinguish the pulp vitality (a function of vascularisation) and the pulp sensitivity (a function of innervation). If the injury causes an interruption of the pulp vascularisation it will lead to the death of pulp tissue including the nerve, and if only the injury of the nerve occurs, the vitality of the pulp is not endangered. The aim of this investigation was to evaluate the sensitivity of teeth involved in jaw fracture line as well as to determine the number of denervated teeth and the time period in which reinnervation or revitalisation will occur. 50 patients with mandibular fractures were prospectively analyzed, 39 out of 50 patients had a tooth involved in the fracture line. There were 63 fractures in 39 patients, with 84 teeth involved in fracture line; 48 out of 84 teeth involved in the mandibular fracture line were initially seemingly avital and their reinnervation was followed up. Six weeks after the injury 31% of teeth involved in the jaw fracture were reinnervated, and a year after the injury 81% of teeth were reinnervated. No reinnervation occurred later than one year following injury. One year after the injury 84% of incisors, 75% of canines, 83% of premolars, and 80% of molars were reinnervated. During the second and the third year after the injury no reinnervation occurred but the devitalisation of initially denervated teeth is possible. The pulp is vitally stable one year after injury. Denervated teeth should not be considered as avital and should not be treated if neither clinical nor radiological signs of devitalisation are present. If sensitivity testing is the only criterion for tooth treatment and/or extraction, i.e., if we do not take into consideration the clinical and radiological criteria of devitalisation, 95% of false avital, i.e. only denervated teeth would be considered devitalised and unnecessary treated or extracted.Prijelomna pukotina u kojoj je zub komunicira preko parodontne pukotine s usnom šupljinom, što predstavlja ulazna vrata infekciji. Osim toga, takav zub može izgubiti opskrbu krvlju zbog oštećenja apeksnih žila pa u slučaju nekroze pulpe postaje izvor infekcije. Metode ispitivanja “vitaliteta” zuba osnivaju se na boli tako da dolazi do nerazlikovanja vitaliteta koji je funkcija vaskularizacije pulpe i senzibiliteta koji je funkcija inervacije. Ako ozljeda uzrokuje prekid vaskularizacije pulpe doći će do smrti pulpnog tkiva uključujući i živac, a ako dođe samo do ozljede i ispada funkcije živca, vitalitet pulpe nije ugrožen. Cilj ovog rada bio je ispitati promjene “vitaliteta”, tj. senzibiliteta zuba u prijelomnoj pukotini donje čeljusti i utvrditi u kojem broju i u kojem vremenskom razdoblju će doći do normalizacije senzibiliteta zuba ili do devitalizacije. Prospektivnom analizom obrađeno je 50 bolesnika s prijelomom donje čeljusti. Zub u prijelomnoj pukotini imalo je 39/50 bolesnika. Analizirano je 39 bolesnika s ukupno 63 prijeloma i 84 zuba u prijelomnoj pukotini, od čega je 48 bilo inicijalno “avitalno”. Mjesec i pol nakon ozljede reinervirano je 31%, a godinu dana nakon ozljede 81% inicijalno “avitalnih” zuba u prijelomnoj pukotini. Godinu dana nakon ozljede reinervirano je 84% sjekutića, 75% očnjaka, 83% pretkutnjaka i 80% kutnjaka. Tijekom druge i treće godine ne dolazi do reinervacije, ali moguća je devitalizacija denerviranih zuba. Pulpa zuba je vitalno stabilna godinu dana poslije ozljede. Denervirani zub ne treba smatrati devitaliziranim i ne treba ga liječiti i/ili ekstrahirati ako nema kliničkih ili radioloških znakova devitalizacije. Kad bi ispitivanje senzibiliteta bilo jedini kriterij za ekstrakciju, tj. kad ne bismo uvažavali kliničke i radiološke kriterije devitalizacije, 95% lažno avitalnih, tj. samo denerviranih zubi proglasili bismo devitaliziranima i nepotrebno ih liječili ili ekstrahirali
