2. L. EL ASSASSE, S. BOUTACHALI, F. AMRAOUI, T. AMIL, S. CHAOUIR, A. DARBI Radiology service, Military hospital, Rabat, Morocco

3.  The mandibular actinomycosis is a rare condition, usually secondary to tooth extraction, mucous wound or mandibular fracture.  We report in this work two cases of mandibular actinomycosis explored by orthopantomogram and facial CT and whose diagnosis is confirmed by histology.

4.  These two patients aged 26 and 60 years, both having a history as a dental extraction with delayed mucosal healing, having presented a mandibular pain with perimandibular tumefaction.  Radiological aspects were not specific with uni or multigeodic osteolysis.

5.  A wide excision was indicated for them with empiric antibiotic therapy.  Pathological examination of surgical specimens revealed actinomycotic osteitis.

6. Case 1: Orthopantomogram showing a left pre-angular osteolytic lesion.

7. Case 1: Facial CT showing well defined multilocular osteolytic lesion in the horizontal branch of left mandible.

8. Case 2: Orthopantomogram showing a left parasymphyseal unigeodic osteolytic lesion.

9.  The cervicofacial actinomycosis is a rare infectious disease whose incidence is estimated at 5 per 100,000 people.  It is most frequent in adults between 20 and 60 years with sex ratio 3 males to 1 female.  It is caused by germs long regarded as intermediate between fungi and bacteria but which proved to be true bacteria: Actinobacteria or actinomycetes.  Involvement of the head and neck region is the most frequent (50 to 75% of cases), thoracic and abdominal locations are rarer.

10.  Contributing factors sometimes found are poor oral hygiene, oral trauma or surgery, dental procedures and salivary lithiasis.  Chronic tonsillitis, mastoiditis, and otitis are also important risk factors for actinomycosis.

11.  The radiological signs of actinomycotic osteitis are not specific.  Involvement may be osteolytic (uni or multigeodic) or osteoblastic.  The severe forms of mandibular actinomycosis can develop into the skull base or cervical spine.

12.  Diagnosis is histological.  Treatment consists of prolonged antibiotic therapy and surgical debridement.  Prognosis depends on early diagnosis and treatment.

13.  The diagnosis of actinomycosis should be considered in patient with recurrent and chronic suppuration.  The appearance on imaging is not specific and the diagnosis of certainty is histological.

14.  Chobaut.J.C, Maniere.C. et coll. L'actinomycose en ORL. A propos d'un cas localisé aux fosses nasales. Ann. Oto-laryngol. Chir. Cervicofac. (Paris). 1994, 111 :292-294.  Simony.J, Puissant.A. et coll. Un cas d'actinomycose cervicale évoluant depuis trois ans sans traitement. Ann. Dermatol. Venereol. 1986 ; 113 : 555 – 558.  Del Rosario.N, Rickman.L. Letters. Cervico-facial actinomycosis. Arch. Otolaryngol. Head neck. Surg. 1987 ;113 :777-778.  Gorlin.R.J, Goldman.H.M. (Eds) Thomas oral pathology. St louis, mosby, 1970.  Sodagar.R, Kohoute.E. Actinomycosis of tongue as pseudotumor. Laryngoscop. 1972 ; 81 : 2149 – 2152. 6) Antoine.G.A, Antoine.J.A. Cervicofacial actinomycosis. Ear nose Throat. J. 1986 ; 65 :483-485.

15.  Walker.R.S, Middelkamp.J.N. et coll. Mandibular osteomyelitis caused by actinomyces israelii. Oral. Surg. 1981 ; 51 : 243-244.  Stenhous.D. Intraoral actinomycosis. Report of five cases. Oral. Surg. 1975 ; 34 : 547-552.  Vannier.J.D, Schaison.G. et coll. Actinomycosis osteomyelitis of the skull and atlas with lace dissemintion. Eur. J. pediatr. 1986 ; 145 :316-318.