Initial situation
A 76-year-old lady who complained of gum swelling and tooth mobility was a known case of hypertension and hyperlipidemia (Fig. 1). She was taking antihypertensives regularly (amlodipine 5 mg at night; losartan 50 mg QD). In addition, this patient had undergone a left hemithyroidectomy in 2018, as well as a spinal fusion many years ago. The patient was fit and ambulatory without any acute distress. Preoperative blood tests showed that she had mild vitamin D deficiency. Clinically, this patient suffered from multiple missing posterior teeth in her upper and lower jaws. The remaining teeth were diagnosed with secondary caries, chronic periodontal disease with clinical attachment loss, defective fillings and failing crown and bridgework (Fig. 2). Radiological examination further revealed that the three anterior mandibular implants had extensive peri-implant bone loss, which was consistent with a clinical diagnosis of severe peri-implantitis.
Treatment planning
After undergoing a CBCT scan, the patient’s DICOM files were exported for computer-aided implant planning (Figs. 3a,3b). Third-party software was used for segmentation and simulation. To respect the biology and biomechanics for optimal functional and esthetic outcomes, the treatment plan was formulated according to the principles of prosthetically driven implant planning (Figs. 4a,4b). Important planning considerations included the distribution of the dental implants in a wider arc, the placement of dental implants according to the future tooth position, and the elimination of a distal cantilever on the prosthesis.