Effectiveness of 3D-printed Patient-specific Resorbable Scaffolds for Maxillary Bone Regeneration

A parallel‐arm randomized clinical trial will be designed. The participants will beelderly patients from the city of Valdivia, Chile, regardless of sex, from the DentalHealth Service of the Base Hospital of Valdivia for dental rehabilitation with dentalimplants. Clinical characteristics and complete medical history (such as sex, age andcomorbidities) will be recorded and all the information that allows the identification ofthe patients will be encrypted.Patients requiring bone regeneration at the time of examination should have an atrophicbilateral mandible with poor bone available according to periodontal diseasesclassification behind tooth #3.3 or #4.3; with an edentulous alveolar ridge with aremaining bone height of ≤ 6 mm. Patients will be excluded if they have had previousdental implant surgeries, with maxillary sinus pathologies, with oral tissue lesions,diseases that produce acute/chronic pain, smokers of more than 5 cigarettes per day, withexcessive alcohol consumption (more than three times per week), and who suffer from anysystemic disease whose surgical intervention is prohibited, for example: severe heartdisease, congenital coagulation factor deficiency, dialysis, or malignant tumor interminal phase. Also excluded are patients with diabetes that is not well controlled orwho have difficulty achieving an Hb ≥ 7 g/dL in a preoperative examination; patientstaking any anti‐platelet or anticoagulant drug and patients with a history of heartdisease. ‐ Sample size calculation Considering as the main objective of this study theformation of vital and functional bone analyzed in histological specimens, for thesample calculation the researcher relied on the randomized clinical trial of Goh etal. who demonstrated a difference in the percentage of bone formation using PCL bonematrices in bone preservation was 9.5%. As a result of using this effect size with agiven alpha level of 0.05, a power of 80% and an allocation ratio of 1, the samplesize was 4 patients per group (algorithm: mean power 1 9.5, sd(3.6). STATA v.14.0..Furthermore, taking into account that each patient will use both sides of their jaw (leftand right), with two study groups and a 25% loss to follow‐up or sample processing error,estimating that a total of 10 patients will participate in this study. ‐ Study groups and randomization ‐ Osteoprint group: Patients with a jaw/maxilla atrophy in which the 3D scaffold with PCL will be inserted. ‐ Control group: Patients with a jaw/maxilla atrophy which will be regenerated using the conventional technique using a titanium reinforced polytetrafluoroethylene (PTFE) membrane (Cytoplast® brand) and filling the space with Bio‐Oss xenograft (Geistlich Pharma Agency. Germany). ‐ Randomization: The mechanism to perform the randomization sequence will be using the"RANDBETWEEN" function of Microsoft Excel® v.15.24.2016 (Microsoft, Sacramento.USA). An researcher will randomize in a spreadsheet with three columns: the firstcolumn with the patient number, the second column with the maxilla/mandible side tobe used (#1 right side; #2 left side) and the third column with the type of studygroup to be used (#1: experimental group; #2: control group). This sequence will bepreviously determined by an investigator and will be informed before surgery,according to the number of patients to be operated. ‐ Experimental Design To analyze the osteogenic capacity of the 3D printed bonescaffold with PCL, an researcher will compare the volume of bone formed in the areausing the 3D printed bone scaffold with PCL+ βTCP (experimental group) versus thevolume of bone regenerated using a titanium‐reinforced polytetrafluoroethylene(PTFE) membrane (control group). The outcome will be measured in histomorphometryand immunohistochemistry of bone biopsies obtained at six months.