Measurement of biochemical markers of bone turnover in patients with bilateral sagittal split osteotomy

In certain pathological diseases of the bones there are bone related
biochemical parameters. There are studies in which osteomyelitis of the
mandible is diagnosed and followed during treatment through bone-specific
biochemical markers (Springer et al. A new method of monitoring osteomyelitis
Int. J. Oral Maxillofac. Surg. 2007;36: 526-532). In case of an osteomyelitis
of the mandible it is often possible to diagnose a patient based on clinical
examination and plain x-ray of CT-scan. Treatment of osteomyelitis is often
long-lasting oral antibiotics, sometimes combined with surgical sequestration.
It is however very difficult to measure to which extent there is still an
active infection. The choice to stop or continue the treatment with antbiotics
is therefore difficult.
The report that biochemical markers for bone turnover can be used in the
diagnostic process and treatment of osteomyelitis of the mandible is clinically
relevant. There are however no normal values in the remodeling or recovery of
mandible bone. There are normal values of other long bones as the femur or
radial bone. Due to the relative small size of the mandible it is however
questionable whether remodeling of this bone is even measurable at all. In
normal infection of the mandible or maxilla the usable infection parameters
(CRP, leucocytes) are seldom above normal. This is why the current
investigation will be if bone specific biochemical markers change measurable
during the process of bone recovery in a clinical model. The data from this
research will be a reference for future research in bone specific biochemical
markers in pathological conditions. As a model in this study we have chosen for
the bilateral sagittal split osteotomy (BSSO) of the mandible.
During a BSSO the length of the mandible is being corrected. The mandible is
bilaterally split and fixated in its new position (often more ventral). After
this BSSO the broken mandible will remodelate into a complete mandible. This
takes a maximum of 3 months according the normal fracture healing.
During remodeling of the mandible several biochemical markers will be released
to the blood and filtered in the urine. This study will measure whether the
biochemical markers in serum (CTX, P1NP, BALP, Osteocalcine, Calcium, vit D.
CRP, BSE, leucocyten, IL6, creatine) and urine (hydroxylysylpyridinoline en
lysylpyridinoline) undergo changes that fit a systemic change.

Primary Objective:
- Are there mesurable changes in biochemical markers after BSSO in serum(CTX,
P1NP, BALP, Osteocalcine, Calcium, vit D. CRP, BSE, leucocyten, IL6,
creatine) and in urine(hydroxylysylpyridinoline en lysyspyridinoline)?
- Can serum and urine biochemical markers predict bone remodeling?

Cohort study

Simultaneously with the regular post-operative controle there will be three
vena-punctures. Next to that patients will collect midstream morning urine for
analysis at home.