**7. Radiotherapy treatment and implants**

*Oral and Maxillofacial Surgery*

**Figure 4.**

Three-dimensional printing has been used to produce anatomical models, surgical guides and templates, implants, and molds. The main advantages include: the possibility of preoperative planning, the precision of the process used and the time saved in the operating room. However, other studies report inconsistency in

*Photograph of surgical field after placement of zygomatic and Pterygomaxillary implants.*

The maxillofacial reconstruction with osseointegrated implants simulated in a biomodel, allows to determine the lengths and final positions of the implants, prepare the surgeon for the surgical procedure and minimize the possibilities of

Oral and facial deformity can cause functional and psychological deterioration in oncological patients. The aims of prosthodontic reconstruction are the rehabilitation of the shape, function and esthetics of the lost anatomical structures by means of artificial substitutes. The main facial subunits that require reconstruction due to malignant pathological processes involve the ear, forehead, eyes and brow, nose,

Currently, there are multiple workflows where they combine conventional prosthetic preparation with the use of facial scanners and custom 3D impressions

precision and additional costs in treatment [32].

**6. Prosthetic and facial reconstruction**

check, lips and chin [33].

errors favoring the results of the treatment (**Figures 3** and **4**)**.**

*Photograph showing implant-supported obturator placed and final photograph.*

**168**

**Figure 5.**

In early clinical stages, surgery is the first decision. However, adjuvant radiotherapy is sometimes indicated in cases of close excision margins (<5 mm), involved (<1 mm), and in suspicion or confirmation of lymph node metastasis with or without extracapsular extension [36]. In general, radiation therapy includes conventional radiation therapy or intensity modulated radiation therapy (IMRT). The latter is more convenient by precisely targeting radiation to a specific area and reducing the dose to nearby anatomical structures such as malar bone, grafts, implants, salivary glands, eyes, and spinal cord [37].

Schiegnitz's study suggests that radiation negatively affects implant survival, but there is no statistically significant difference in survival when implants are inserted 12 months before or after radiation therapy [38]. Other authors have shown favorable results. With implantation at least 6 weeks before radiotherapy since there is a surgical area with less hypoxia, hypovascularity and hypocellularity [27, 39] (**Figure 6**).

**Figure 6.** *Histogram showing trajectories, dose and volume used for adjuvant radiotherapy.*
