Clinical Implications of Bisphosphonate Therapy on Orthodontic Treatment Planning: A Systematic Review of Experimental Evidence

Bisphosphonates are synthetic analogues of pyrophosphate with a high affinity for hydroxyapatite and potent inhibitory effects on osteoclast-mediated bone resorption. Widely used in the management of metabolic bone diseases, they may significantly influence orthodontic tooth movement (OTM) and treatment outcomes. This study aimed to evaluate the clinical implications of systemic and local bisphosphonate administration for orthodontic treatment planning with particular emphasis on tooth movement, anchorage control, root resorption, and treatment-related outcomes. A systematic literature search based on the PICO framework identified 32 experimental animal studies investigating the effects of bisphosphonates on OTM and related biological parameters. Due to substantial heterogeneity in study design, animal models, and outcome measures, a semi-quantitative synthesis was conducted. Subgroup analysis comparing local versus systemic administration was performed to assess differences in treatment effects. Most included studies reported a reduction in OTM following bisphosphonate administration, indicating a consistent inhibitory effect that appears dose- and time-dependent. Semi-quantitative synthesis demonstrated a marked decrease in tooth displacement across studies. Local administration resulted in more site-specific inhibition, whereas systemic delivery produced a generalized suppression of bone remodeling. Reduced osteoclast numbers or activity and decreased root resorption were frequently observed. Additional findings included improved anchorage control and reduced relapse tendency. However, procedures requiring new bone formation, such as suture expansion, were negatively affected. Bisphosphonates reduce orthodontic tooth movement primarily through inhibition of osteoclastic activity, which may prolong treatment duration. However, they may provide clinical benefits in anchorage reinforcement and relapse prevention. As these findings are based on animal studies, they should be interpreted with caution, and clinical validation is required. Clinicians should anticipate slower tooth movement in patients receiving bisphosphonate therapy and adjust treatment planning accordingly. At the same time, these agents may offer potential advantages for anchorage control and relapse prevention. Careful medical history assessment and patient communication are essential when managing such cases.