Head and neck cancers are the 7th most common malignancy worldwide. Radiotherapy plays and important role in treatment with around 75% of patients receiving the therapy. Osteoradionecrosis is a side-effect of radiotherapy although the pathogenesis is unclear traumatic events such as tooth extractions are considered to be a risk factor. Tooth extractions may be carried out before or after radiotherapy and there is some debate regarding extraction protocols.
The aim of this review was to estimate the osteoradionecrosis rate in patients with head and neck cancer due to teeth extraction performed before radiotherapy.
The review protocol was registered on the PROSPERO database and searches conducted in the PubMed, Scopus and ISI Web of Science databases. Prospective and retrospective (cohort and case–control) and randomised clinical trials (RCTs) in patients who received radiotherapy for cancers in the head and neck region were considered. Papers with a minimum sample size of 10 patients a follow- up period of 6 months and published in English were included. Two reviewers selected studies and extracted data with study quality being assessed using the Newcastle-Ottawa scale for observational studies the Jadad scale for RCTs. meta-analysis was carried out using a random effects model
- 8 studies (1 RCT, 7 retrospective) involving a total of 1,249 patients were included.
- 494 patients had teeth extracted before radiotherapy.
- There were 90 cases of osteoradionecrosis with 16 being linked to tooth extraction.
- The pooled osteoradionecrosis incidence for extractions prior to radiotherapy was 2.2% (95% CI: 0.6% to 3.9%).
- No studies controlled for other risk factors such as oncologic surgery or anti-resorptive drugs.
The authors concluded: –
….this systematic review confirmed that teeth extractions before radiotherapy represent a risk factor for osteoradionecrosis; the considerable amount of missing data prevented us from identifying other possible risk factors for osteoradionecrosis onset.
The authors searched 3 major databases although restricting the inclusions to English language papers may have excluded some relevant papers. The Jadad scale is no longer recommended for assessing the quality of RCTs with tools like domains-based the Cochrane risk of bias tool being preferred. However only one of the included studies was an RCT with the remainder all being retrospective. While the findings suggest that tooth extraction prior to radiotherapy was a risk factor for osteoradionecrosis none of the studies had controlled for other potential risk factors as highlighted by the authors. Of the 1,249 patients included in the review 90 had osteoradionecrosis with only 16 being linked to tooth extraction.
Earlier this year we highlighted another review by Beaumont et al (Dental Elf – 21st Apr 2021) which compared the incidence of dental extractions before or after radiotherapy. Only 3 studies were common to both reviews with the Beaumont review reporting a pooled incidence of osteoradionecrosis of 5.5% (95%CI; 2.1% to 10.1%) for pre-radiotherapy extractions compared with the 2.2% (95% CI: 0.6% to 3.9%) reported in the current review. As was highlighted in the 2019 Cochrane review (Dental Elf – 29th Nov 2019) more well-designed and reported prospective studies with larger sample sizes and using commonly agreed definitions and outcome measures are needed to clarify the evidence.
Lajolo C, Gioco G, Rupe C, Troiano G, Cordaro M, Lucchese A, Paludetti G, Giuliani M. Tooth extraction before radiotherapy is a risk factor for developing osteoradionecrosis of the jaws: A systematic review. Oral Dis. 2021 Oct;27(7):1595-1605. doi: 10.1111/odi.13485. Epub 2020 Jul 7. PMID: 32531873.
Dental Elf – 21st Apr 2021
Osteoradionecrosis incidence and the timing of dental extractions
Dental Elf – 29th Nov 2019
Osteoradionecrosis of the jaws: Prevention in adult patients with head and neck cancer