Pre-radiotherapy dental extractions and osteoradionecrosis: a retrospective analysis and cross-sectional study on quality of life

Beech, Nicholas (2017). Pre-radiotherapy dental extractions and osteoradionecrosis: a retrospective analysis and cross-sectional study on quality of life MPhil Thesis, School of Medicine, The University of Queensland. doi:10.14264/uql.2017.338

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
s4081830_mphil_thesis.pdf Thesis (open access) application/pdf 561.83KB 0
Author Beech, Nicholas
Thesis Title Pre-radiotherapy dental extractions and osteoradionecrosis: a retrospective analysis and cross-sectional study on quality of life
School, Centre or Institute School of Medicine
Institution The University of Queensland
DOI 10.14264/uql.2017.338
Publication date 2017-02-10
Thesis type MPhil Thesis
Supervisor Martin Batstone
Sandro Porceddu
Total pages 68
Language eng
Subjects 110323 Surgery
Formatted abstract
Background
Radiotherapy (RT) is widely utilised for the management of head and neck malignancies, and presents a number of morbidities. One of the most feared late sequelae is osteoradionecrosis of the jaws (ORN). Many risk factors for ORN exist including radiation delivery, dose and fractionation, tumour location, smoking and alcohol use, general health and nutrition status, oral health and oral hygiene. There also exist triggers that increase the likelihood of ORN developing, such as dental extractions, surgery or poor fitting prostheses as well as any residual foci of infection.

In order to prevent post-radiotherapy dental extractions and therefore reduce the risk of developing ORN, it has been advocated that dental extractions are performed prior to radiotherapy. However, there is contention that such pre-RT extractions may actually increase the risk of developing ORN. Newer RT technologies and techniques deliver a lower dose to the jaws and critical structures, and coupled with improved oral hygiene methods radiotherapy related dental disease can be limited and the chances of retaining a functioning dentition greatly improved.

Head and neck cancer diagnosis and treatment places a heavy stress on patients and impacts their quality of life. Independent of a cancer diagnosis, edentulism is associated with reduced oral function and health related quality of life.

Aims
1. To determine if pre-radiotherapy dental extractions are associated with an increased risk of developing ORN.
2. To determine if pre-radiotherapy dental extractions are associated with a reduced health related quality of life.

Methods
Regional and site-specific ethics approval was obtained. Patients over the age of 18 who were treated with radiotherapy for oropharyngeal cancer at two tertiary Australian hospitals between 2005 and 2011 were invited to participate in the study. All participants were presented to a head and neck MDT and underwent pre-radiotherapy dental assessment. Demographics and retrospective analysis of the treatment details of the 190 consenting participants were recorded. Participants completed questionnaires regarding their oral hygiene, dental extractions and dental experience. A diagnosis of osteoradionecrosis was confirmed. Participants also returned two health-related quality of life forms, the OHIP-14 and FACT-Head and Neck, which were utilised according to their guidelines. The FACT-Head and Neck results were used to calculate subset scores and the outcome scores FACT-G, FACT-TOI and Fact Total. Multivariate logistic regression was performed.

Results
190 participants were recorded, of whom the majority were male (82.6%) and underwent concurrent chemotherapy and radiotherapy (87.9%) with a mean dose of 68 Gray. 67.9% underwent pre-radiotherapy dental extractions with a mean of 5.1 teeth. Mandibular teeth were favoured 1.7:1. Current smokers were more likely to undergo extractions (p=0.02). No teeth were extracted during radiotherapy. 30 participants underwent post-radiotherapy extractions, 20 of which after already receiving pre-radiotherapy extractions. The mean number of teeth extracted was 0.85 and did not favour either arch.

29 participant (15.3%) developed ORN in the follow up period, favouring the mandible (89.6%).

Pre-radiotherapy dental extractions were associated with the development of ORN (OR 3.19, p<0.05). The number of extractions was associated with an increased risk of ORN (OR 1.13 per extraction, p<0.05). Post radiotherapy extractions were associated with a similar odds ratio but were not statistically significant. Current and ex-smokers were at an increased risk of developing ORN compared with non-smokers, as well as p16 negative status.

The range of quality of life outcome scores were broad and nearly encompassed the entire possible scores. OHIP-14 scores showed a statistically significant worse QoL for females, p16 negative status and stepwise in smoking status from current to ex to non-smokers. More than 8 pre-radiotherapy extractions, pre-radiotherapy full clearance and the development of ORN also produced statistically significant associations with a worse QoL. The only measure associated with an improved QoL was current excellent dental hygiene.

FACT-Head and Neck showed that smoking status was associated with a global reduction in QoL across the subset scores emotional well being, social well being, functional well being, physical well being and head and neck specific scores. P16 negative cases were associated with reduced QoL in the social well being and head and neck specific domains. Female gender was associated with reduced QoL in the emotional well being domain.

Conclusion
Pre-radiotherapy dental extractions do not appear to reduce the risk of ORN, and may in fact increase the risk. Pre-radiotherapy dental extractions do not increase health related quality of life, and may in fact worsen it.
Keyword Radiotherapy
Dental extractions
Osteoradionecrosis
Quality of life
Head and neck cancer

Document type: Thesis
Collections: UQ Theses (RHD) - Official
UQ Theses (RHD) - Open Access
 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Wed, 08 Feb 2017, 15:06:16 EST by Nicholas Beech on behalf of Learning and Research Services (UQ Library)