Outcomes of immediate dental implants in vascularised bone flaps for mandibular reconstruction

BACKGROUND

The aim of this study is to assess the outcomes of immediate implant placement for dental rehabilitation following mandibular reconstruction with vascularised bone flaps in a single Australian tertiary cancer centre.

METHODS

A retrospective analysis of patients who underwent immediate dental implant or delayed placement in vascularised bone flaps was performed. Primary outcome measures assessed included the number of implants placed, operative time, complication rates, time to radiotherapy initiation, dental rehabilitation rates and time to dental rehabilitation.

RESULTS

In total, 187 dental implants were placed in 52 patients, of which 34 patients underwent immediate implant placement and 18 had delayed implant placement. There were no significant differences in the postoperative complication rate (32% immediate vs. 33% delayed, P = 0.89) or time to postoperative radiotherapy (median 42 days immediate vs. 47 days delayed, P = 0.24). Dental rehabilitation was achieved in 62% of the immediate cohort versus 78% of the delayed cohort. The time to be fitted with a dental prosthesis was significantly shorter in the immediate cohort (median 150 days immediate vs. 843 days delayed, P = 0.002).

CONCLUSIONS

The placement of immediate dental implants at the time of primary reconstruction of the mandible is a safe procedure and facilitates timely dental rehabilitation.

Analysis of the Ki-67 antigen at the invasive tumour front of human oral squamous cell carcinoma

BACKGROUND

It is hypothesised that cell proliferation, as measured by the Ki-67 labelling index (LI) at the invasive tumour front (ITF) was directly related to the histological grade in human oral squamous cell carcinomas (SCCs).

METHODS

Tissues from 42 human oral SCCs were collected and stained with an antibody directed against the Ki-67 antigen using an advanced polymer staining system. Quantitation of the immunopositive cells was performed on two parallel sections at the invasive tumour front (ITF), using an image analyser. The Ki-67 LI was expressed as the number of positive nuclei/mm2 of epithelium. The control tissue used was normal epithelium at the excision margin.

RESULTS

The mean Ki-67 LI for oral SCCs at the ITF was significantly greater than that for the excision margin tissue (P < 0.0001). There was a positive association between increasing Ki-67 LI and increasing Broders' grade (P < 0.05), with a well-differentiated tumour having the lowest mean Ki-67 LI (1549 +/- 806) and a poorly differentiated tumour having the highest value (2232 +/- 771). A similar trend was observed between the mean Ki-67 LI and Bryne's multifactorial grading system.

CONCLUSIONS

It was concluded from this study that cell proliferation (as measured by the Ki-67 antigen) at the ITF had a strong positive relationship with histological grading in human oral SCC.

Displacement of a mandibular third molar root fragment into the pterygomandibular space

Displacement of root fragments into adjacent anatomical areas is an uncommon complication of the removal of teeth. This paper describes the management of a mandibular third molar root fragment that was forced into the antero-inferior aspect of the pterygomandibular space. The importance of tomographical radiographs in the visualization of the displaced root is also discussed.