Prevalence of osteonecrosis of the jaw in patients with oral bisphosphonate exposure.
OBJECTIVE
Osteonecrosis of the jaw (ONJ) is a serious complication associated with bisphosphonate therapy, but its epidemiology in the setting of oral bisphosphonate therapy is poorly understood. The present study examined the prevalence of ONJ in patients receiving chronic oral bisphosphonate therapy.


METHODS
We mailed a survey to 13,946 members who had received chronic oral bisphosphonate therapy as of 2006 within a large integrated health care delivery system in Northern California. Respondents who reported ONJ, exposed bone or gingival sores, moderate periodontal disease, persistent symptoms, or complications after dental procedures were invited for examination or to have their dental records reviewed. ONJ was defined as exposed bone (of >8 weeks' duration) in the maxillofacial region in the absence of previous radiotherapy.


RESULTS
Of the 8,572 survey respondents (71 +/- 9 years, 93% women), 2,159 (25%) reported pertinent dental symptoms. Of these 2,159 patients, 1,005 were examined and an additional 536 provided dental records. Nine ONJ cases were identified, representing a prevalence of 0.10% (95% confidence interval 0.05% to 0.20%) among the survey respondents. Of the 9 cases, 5 had occurred spontaneously (3 in palatal tori) and 4 occurred in previous extraction sites. An additional 3 patients had mandibular osteomyelitis (2 after extraction and 1 with implant failure) but without exposed bone. Finally, 7 other patients had bone exposure that did not fulfill the criteria for ONJ.


CONCLUSIONS
ONJ occurred in 1 of 952 survey respondents with oral bisphosphonate exposure (minimum prevalence of 1 in 1,537 of the entire mailed cohort). A similar number had select features concerning for ONJ that did not meet the criteria. The results of the present study provide important data on the spectrum of jaw complications among patients with oral bisphosphonate exposure.
Lo
Joan C
JC
Research Scientist, Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA. Joan.C.Lo@kp.org
O'Ryan
Felice S
FS
Gordon
Nancy P
NP
Yang
Jingrong
J
Hui
Rita L
RL
Martin
Daniel
D
Hutchinson
Matthew
M
Lathon
Phenius V
PV
Sanchez
Gabriela
G
Silver
Paula
P
Chandra
Malini
M
McCloskey
Carolyn A
CA
Staffa
Judy A
JA
Willy
Mary
M
Selby
Joe V
JV
Go
Alan S
AS
D000284:Administration, Oral; D000368:Aged; D019386:Alendronate / Q000008:administration & dosage / Q000009:adverse effects; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000009:adverse effects*; D002140:California / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004164:Diphosphonates / Q000008:administration & dosage / Q000009:adverse effects*; D012968:Etidronic Acid / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D000077557:Ibandronic Acid; D007571:Jaw Diseases / Q000139:chemically induced* / Q000453:epidemiology; D008297:Male; D010020:Osteonecrosis / Q000139:chemically induced* / Q000453:epidemiology; D015995:Prevalence; D000068296:Risedronic Acid; D011795:Surveys and Questionnaires; D014081:Tooth Extraction / Q000009:adverse effects
D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D000068296:Risedronic Acid; D012968:Etidronic Acid; D000077557:Ibandronic Acid; D019386:Alendronate